Convert Crayons into 2mm+ Leads Like Graphite Lead

Hello! I want to recycle crayons and thought of converting them into 2mm lead or larger in diameter (since there’s only a certain thickness where crayons can be sturdy). I also thought the crayons should be mixed with something since they’re wax. I was thinking of buying a silicone mold rubber to make a mold (may make the lead bend since it’s flexible but easy to remove), a polyurethane mold rubber, or a protruder like the old fashioned way. Silicone mold rubber is expensive ($30+). I originally thought of it as a craft, but it’s too complicated for a craft. Thank you for your time!

Topic by TrixiaL 1 year ago  |  last reply 1 year ago


how do i make my airsoft gun stop making the bbs curve up? Answered

Every time i shoot, the bb curves up and away from the target, even when i line up the sites correctly.

Question by nerfer 10 years ago  |  last reply 7 years ago


What kind of cable or tube would you use to join 2 knitting needles of 2mm-3.5mm diameter? Answered

I am looking to create custom circular needles--each of which consists of 2 1-pointed needles connected by a smooth, flexible cable. This project is to provide access to knitting socks and certain other projects to a friend whose physical limitations make it impossible without the following: ~~~~ Circular knitting needles of which the metal needle portions are no less than 10" in length and between 2mm and 3.5mm in diameter. Cable length may be between 20cm-80cm depending on the project. ~~~~ What I'm stuck on is what kind of cable to use and how to attach said cable so that the yarn slides over it smoothly, going either way over the join. I can either cut the ends off of straight needles or use needles with double points--I thought the double pointed ones would allow the needle to slide into a hollow cable that could be meddled with so as to make a smooth join. it is possible that the larger needles are hollow and could have a cable inserted, but that would be very small. I am happy to entertain the idea of other material for the needles--it must be strong enough to do stitches without flexing. Bamboo has been tried and is out, given the length and diameter. The needles I have on hand are, as far as I know, made of steel. If I get anywhere, I'll post an 'Ible. Thanks in advance, Wicken

Question by 0jack 8 years ago  |  last reply 8 years ago


How i can make prism?

I want make prism of window glass 2mm . After cut glass side became not smooth. How can i polish side of prism?

Question by SevaKaptur 8 years ago  |  last reply 8 years ago


How would one go about making very small square holes a thin piece of metal?

I'm trying to modify a bracelet that's made out of some very, very thin metal, and I need to make several small square holes all over it. By small, I'm talking 2mm x 2mm small, and they have to be noticeably square shaped. Is there any cleaner way to do this than trying to drill a small hole and using a super small file (if such a thing exists, haha)?

Question by Ingulit 5 years ago  |  last reply 5 years ago


Metric Tube Supplier?

Does anyone know of any good steel tubing suppliers. I need a few different sizes, all of which cannot be found at any local hardware store, in square and rectangular shapes. Also, I found one supplier already and they had so many sizes to choose from. But they only ship large quanities to companies, not to the individual. So if anyone knows of any suppliers that can supply the following sizes for a decent price, your help would be very much appreciated. The sizes I need are 40mm square with 2.5mm wall, 25.4mm square with 2.5mm wall, 20mm square with 2mm wall, 40X20mm with 2mm wall, 35X16mm with 1.5mm wall.

Question by bombmaker2 8 years ago  |  last reply 2 years ago


Help identify small IC chip

- Found in LED light assembly  - DIP package with 5 gull wing leads in the 1,2,3,4 & 6 positions, as referenced below 6____5____4 |                      | |__________| 1         2         3 - Top says "TF98" - Bottom says "S354" - Small, about 1mm X 2mm

Question by shuo888 7 years ago  |  last reply 7 years ago


where to get fiber optic scraps for art project

Where can I get fiber optic scraps, 1-2mm glass for an art/tech project? 2-5 ft long about a laundry basket  to small truck bed full.        Houston TX

Topic by broodinghen 5 years ago  |  last reply 5 years ago


Can't publish changes to a Instructable

This may be a duplicate question but I can't seem to find the initial post.Have have made edits to an instructable. I can see them in the edit or preview screens but not when using the public view. Looking at the attached photos, the one with the referece to 2mm acrylic is in the edit view and the other is the public view.I have tried clearing my cache, different networks, computers and ISPs.I could try unpublishing and republishing but I am concerned that I will loose the "Featured" rating and viewing stats.I have two questions: Can anyone else see new reference to 2mm Acrylic in the first step? Does anyone have anu advice on where to go from here?https://www.instructables.com/id/LED-Jigsaw-Puzzle-Light-Acrylic-Laser-Cut/

Question by abasel 3 months ago  |  last reply 3 months ago


Is it possible to transfer data via magnetic induction between two coils separated by a steel plate ?

Is it possible to transfer data via magnetic induction between two coils separated by a thin steel plate of 2mm ? Or does the magnetic field gets diminished by the metal plate?

Topic by ZZamorin 2 years ago  |  last reply 2 years ago


Is there any drawing software used to draw circles of any size? Coz for one project I need to make a templet .

Is there any drawing software used to draw circles of any size? Coz for one project I need to make a templet of 4cm radius circle and inside the circle i need to evenly distribute 22 holes with size 2mm?

Question by Rohitrai 9 years ago  |  last reply 9 years ago


Recipe for tapioca pearls? Something that doesn't require an oven...(but no bubble tea)

I have a 400g packet of small (2mm diameter) tapioca pearls that I would like to use up. I have a gas stove, no oven, no microwave so I'm looking for some kind of stew or salad recipe,  or just anything that I can cook on the stove top.

Question by BlueberryCrazy 7 years ago


How to attach a wire to a tiny SMD board

I'm working on moding a cheap mp3 player. I want to relocate the power switch. The SMD components are tiny and I just destroyed a small component (diode) with my weller temp controlled soldering iron. Any suggestions on how to attach a small wire to a really tiny spot (1.5mm x 2mm),

Topic by ifranz 9 years ago


What's the best method of creating a transparent, protective coating for custom aluminum coasters?

I have 4x4 inch metal coasters (for placing drinks on) which are made of aluminum and I don't want them to get scratched.  What's the best type of protective coating I can place on top of the metal to prevent scratching?  The coating would preferably be less than 2mm thick, be smooth, and dry very hard.

Question by Joe426 7 years ago  |  last reply 7 years ago


iPod Touch Battery Thickness (need thin battery)

Does anyone know the thickness of the 4th gen ipod touch battery?  I'm looking for a thin lithium battery (less than 2mm thick) that has decent capacity (more than 300mAH).  If anyone knows the thickness of the ipod battery (or any other suitable battery) it would be greatly appreciated.

Topic by guyfrom7up 7 years ago


Dremel? Is it any good?

Http://au.dremel.com/html/started/started_fr.htmlI saw this in "Lowes" yesterday and I'm planning on buying it. I'm just not sure if it is worth it or not. I'm actually hoping that this will speed up the process of cutting shapes into steel tubing.The steel tubing I'm cutting is about 2mm thick. Does anyone here have Dremel? If so, please, what are your comments on it? Is it a good tool to cut steel? How long does it take to cut through steel tubing?

Topic by IlluminatedAntichrist 11 years ago  |  last reply 11 years ago


Model bridge

Hello,             What is the best way to construct a model bridge out of small wooden icecream sticks  The requirements are as follows: 1) the icecream stick dimensions are 2mm deep 10mm wide by 115mm long 2) the bridge has to be 1 metre long and about 20-30cm wide 3) the only materials are the wooden icecream sticks , wood glue and cardboard to form the deck of the bridge. The idea is to construct the bridge so as to be able to hold the most weight.The most weight achieved so far is 450 kg before breaking

Topic by jamesk891 5 years ago  |  last reply 5 years ago


Basic LED project

Hi there I have an idea in mind and would like to know if you guys think it would be possible to make. The object is for the battery to last a minimum of 150 hours of constant use. I want to use the smallest possible LED say 2mm or even a SMD will be sufficient, the led must run off a very small battery either a LR44 / CR1225 or something similar in size and the design must have an on off switch.   Do you have any suggestions? Is this even possible? Any ides? Thanks Matt

Topic by b1g5l1ck 8 years ago  |  last reply 8 years ago


Any soldering tips for soldering a VQFN-16 IC? Answered

Its tiny, ≈ 4mm, has 16 pads Have to try to hand solder it. have some really thin solder i think its .2mm? Or should i go with more of a heat gun method (would have to buy a cheap heatgun, would hairdryer work??) chip might also go by 16-VQFN 16-HVQFN, 16-SQFN, 16-DHVQFN its chip TPS61090- both on digikey and mouser thanks

Question by astroboy907 8 years ago  |  last reply 8 years ago


I have a monitor with a broken HDMI port, would there be any way I can repair it or have it repaired?

I have a monitor with a broken HDMI port. Part of the center that holds the pins in broke (About 1.5-2mm) , and the pins are bent all to... Well... That place down there and back. Would there be a possibility that any computer repair place could replace it, or any way I could do it?The warranty is expired, so I can't void it.

Question by Rokko8652 8 years ago  |  last reply 8 years ago


Cold fusion experiment

I have reproduced some experiments on Cold Fusion. not as a source of energy but how to blend a wire of iron from 2mm with less than 2 ampere or obtain gas fuel from the water and graphite (coh4) without using dozens of amps.Do you think may be is interesting to do an instructabels to the matter? are not my nventions!I have same video of this experiment on my youtube channe http://www.youtube.com/user/alessiof76 Almost all in Italian language.. but with a little explanation also in EnglishThe power supply that i use and the experiments can be dangerous.. I would not like someone to dye !

Topic by alessiof76 10 years ago  |  last reply 3 years ago


Wifi Extender

Hello All, Im puzzled by a simple wifi aerial, i have an old pci wifi card which is slow but works perfectly fine, the only downfall is the range so i un-soldered the original antenna and soldered on some copper wire (approx 2mm thick copper) and on the end of this attached a connector and that attached to a new antenna, but that didnt work,  The signal was weaker, i know one option is to go and buy a new better wifi card but i wanted to dabble with creating a stronger wifi aerial, (in my head this would work but in practical it didn't). Why And what did i do wrong?    

Topic by nats0128 3 years ago  |  last reply 3 years ago


where to get small plastic gears, to OEM spec?

There was once a nice Cyberhome DVD player that was cheap and fast and good, but then the pinion gear on the laser carriage motor split, and suddenly it became a piece of junk. I found many sources for small gears, but not the right one. This one is a 12 tooth, 2mm bore, 6mm dia, 6mm tall item that press fits onto the shaft. Based on other posts on other sites, these players are electronic lemmings, and are all soon destined for the dumpster, mostly for this reason. HELP ME SAVE THEM FROM THEIR FATE! Perhaps we're all screwed, and this is not an off the shelf item.

Question by Fixerdad 10 years ago  |  last reply 9 years ago


Where can I buy thin brushed aluminium plates - think Mac trackpad

Hi, I'm trying to source brushed aluminium plates as well as textured brass or copper or magnesium plates, black (aluminium?) plates and 1-2mm thin opaque coloured glass plates - something similar to the glass on a smart phone. I'm looking for materials that I can cut to size or that come in approximate size of 80-120 x 80-120mm x 1mm. This is for use with touch sensitive projects and I'm looking for something that has a premium look and feel. Any tips or pointers would be really helpful.

Question by shauneff 1 year ago


CO2 valve question? Answered

Hi ... I would like to ask for your opinion about my idea : I got as a present a CO2 airsoft pistol. Unfortunately it's too powerful for the UK airsoft norms. So I would like to make it weaker. I took the magazine apart and I had a look at the valve. I find out, that the moving part in the valve (that release the CO2 from cartridge to the gun) is able to move cca 2mm. Now my question is : If I would limit the movement with "something" so that the moving part woudl move only 0.5-1mm ... would this make the gun weaker ??? Thank you for your opinion or any suggestions.

Question by zholy 8 years ago  |  last reply 8 years ago


How do I fix my tesla coil? Answered

My tesla isn't working, and I just want to see if anyone sees a problem. * NST voltage: 10,000 Volts 30 mA * 12 AWG connections wire (radio shack) * 15 feet primary copper tubing * 900 feet secondary winding * Aluminum ducking top load (18 inch diameter) * 12 0.22 uF 2000 volt capacitors (total: 12,000  volts, 0.0073 uF) * 2mm spacing spark gap * ground rod: metal knitting needle If you need more information, just ask (pictures below). Thanks for your help! (I need it to work in half a month)

Question by Comhippy 9 years ago  |  last reply 9 years ago


Would 3 camera flash caps make a strong enough bank for a coil gun?

I've got 2 capacitor banks right now. The first one uses 3 300V, 120uF capacitors, and the second uses 2 16V, 1000uF caps. Is either of these strong enough to make a coil gun that fires 2mm iron pellets at around 200fps? What if I give it a second stage? Also, I've already made 2 coils around plastic tubing, one using 3 layers of 16 gauge wire with 15 turns each, and the other with 5 layers of 20 gauge with 25 turns. Which one would give me the most power?

Question by AndrewJewer1 4 years ago


What is the material with the largest thermal expansion?

I've looked many places online, but none seem to give me the Solid with the largest thermal expansion. It shouldn't be too expensive or hard to come by and it would be great if it could be purchased pre-cut into a square or at least could be cut by hand. This is very important for my upcoming project that I would love to share with you! Thank you so very much! PS: in the length of 6cm and a temperature difference of 41 degrees Celsius (or Kelvin) this material needs to expand by at least 2mm

Question by sky0 8 years ago  |  last reply 3 years ago


How to compress air into a hollow solid without a valve?

Hi  Really need some help with this one, have searched everywhere but cant seem to figure it out. I know there is probably a very easy solution i'm missing so please help. Basically I want to compress CO2 at around 80 psi into a hollow metal. I have drilled a micro hole and created an opening (about 2mm radius) into the metal. My problem is after I compress the CO2 in there how do I remove the compressor nozzle and seal the hole without the CO2 escaping.  The metal is small and there is no place for a valve. Is there such a thing as a self sealing removable valve? Or could I use a valve  with two openings and pump liquid metal (that would than solidify) and seal the hole so I can remove the compressor?

Question by cnaidoo 7 years ago  |  last reply 7 years ago


Electrically conductive clear resin or additive?

I'm looking to craft some tiny 2mm buttons for a smartwatch face plate. I've got the design down, but I can't get the screen to register the presses. After some digging I learned enough about touch screens to know why. The buttons are going to be cast in a clear orange resin designed to pick up light from the screen below them. Does anyone know of a clear additive or resin material that can sufficiently conduct electricity over a distance of no more that 5mm? If you have any scraps of clear white or clear orange resin. Try using it as a stylus on a smart phone or tablet. If the screen registers the press, let me know please! Also, first time posting here, so bare with me if I have overlooked any sort of etiquette. 

Topic by rgorman4 3 years ago  |  last reply 3 years ago


Hard drive magnets near electronics & TFT Screens ? Answered

Hi Folks. I recently bought an e-reader with a TFT screen, I am making a hollow book type case to keep it in & planned to use a couple of salvaged hard drive magnets as a closure. The idea is to encase the magnets into the pages at the open side of the book either at the top & bottom corners or just one pair at the center. My question is could the magnets cause any damage to the screen or the electronics of the e-reader? Please don't give me any over analysed answers describing magnetic field strengths I am making a book cover not a hydro electric generator, I don't wish to blinded by science I just need to know if there is a possibility that a couple of 2mm x 20mm hard drive magnets could do any damage. Thanks in advance for your sensible answers folks. Kev.

Question by Nostalgic Guy 8 years ago  |  last reply 8 years ago


Question on wind turbine design

Are the poles on the top face of your magnets or at the ends? The former arrangement exists in circular disc magnets and the small bar mags used in brushless motors. You may find that you can get more coils in your motor by winding multiple winds around a piece of stiff plastic. Similarly with disc magnets, alternating N/S with a smaller gap between them you may have more magnets and more coils. Also in many hobby brushless motors, the gap between mags and coils is small, 1-2mm. Do you have the mag coil arrangement on both the top and bottom? I am assuming that you have centering bearings top and bottom, but do you have thrust bearings? These are cheap and are simply balls in a nylon ring at the cheapest end of the market. You would have to sandwich these between big washers or metal plate. I think if all of this was done, the efficiency and output would increase. Dave

Question by 10 years ago


I need Magnets arrangement for a wind power using car alternator N42 (20x10x2.5mm) magnets are glued on modified rotor ?

Hi all, I am modifying a car alternator to a PMG .The winding system is 3 phases the diodes are still connected to have a DC voltage and the rotor circuit has thrown away. The rotor have been machined and a steel pipe is weld on it to adjust the diameter.On the surface of the steel pipe I glue the 14 N42 (20x10x2.5 mm) magnets N & S pole alternately to have 7 pair of N&S poles.The number of poles is 14/ph.I am not getting good result at 1150 rpm it gives 15 volts & at 1450 rpm --> 20 volts.But i need around 15 Volts at 300 rpm how could I get it? Please advise magnet arrangement note that gap between magnets and stator is about 2mm. Hasen

Question by hasenbaksh 10 years ago  |  last reply 9 years ago


Lack of experience = trouble ... do you think, you can help ???

Hi ... it's me again, with my stepper motors. Thanks to your previous answers, I was able to find out, that these are really stepper motors and I bought a motor shield for arduino to be able to operate them. I made a successful experiment with one of them (on second picture) ... but when I tried to modify the second motor for "bredboard use" I made a disaster. There where 4 pins that were melted in a plastic, that holds them in fixed position. But when I was trying to desolder them, by using a desoldering wick ... and heated one pin to much that it melted the plastic, it fell out and it got loose from the wire. As you can (hardly see) on the first picture ... I ended with an ULTRA thin wire that is really short(<2mm) and I don't know how to save/fix the motor. Any suggestions ??? Thank you very much in advance. Zholy

Question by zholy 9 years ago  |  last reply 9 years ago


Push/Pull solenoid on a switch or a solenoid valve? Answered

Hi, I have an air supply and, thanks to iceng, a rapidly pulstating (variable speed) 12v Dc power. I would like the air supply to allow through a set amount of air each time. I already have a mechanical switch that works perfectly, allowing the exact amount of air through, I need this air switch to be opening and closing as quickly as possible. Would I be better of using a push solenoid and setting it up with the switch or do you think I will obtain faster speeds using a dedicated solenoid valve? I was looking a this solenoid. (or something like it http://www.ebay.co.uk/itm/Solenoid-Push-Pull-Small-/321714577205?hash=item4ae7aedf35) Though i am not sure about the valve version. Any advice/recommended solenoid (valve or push-pull) would be very helpful. Specs: 4mm pipe (ext diameter) 2mm (int diameter) 6 bar (preferably have the solenoids as small as possible) Thanks

Question by Digital Flame 3 years ago  |  last reply 3 years ago


Question: Best materials to build a meter height elevator (3 floors)

I have a challenge, and that is, to build a 3 floor elevator. The main frame was built using 2mm carbon steel sheet and rivets, and painted blue. The frame, 950mm height, 250mm width. I thought of using doors (two halfs, opening to opposite sides). What I'm lacking is: • the motors to open the doors (already have one for the cabin, which is more sheet); how strong they need to be• the doors; more sheet? They will be on the main frame. And, should the doors slide on a U like tube to prevent them from woobling? or use gear racks weld to the lower part of the door? And, how would I join the doors with the motors, pulleys and belts?. I'm having stupid amounts of difficulty to view how I am to make the doors work. This will run on grafcet, already done too. Just really only need to assemble the doors and its motors.

Topic by PauloD30 1 year ago  |  last reply 1 year ago


best mosfet config for a powerful flyback driver? would a capacitor across the flyback windings improve preformance?

Well i have an instructable on my singing arc project, i tried the simple 555 driving a power mosfet, but they kept burning out. even the IRF840!!! rated for 500V!!! what am i doing wrong? i tryed using a neon lamp with a series resistor of 4.6K ohms (i think) but it didnt help at all, in fact, it wouldn't even light, yet i got a nasty shock and 2mm spark from the 555 timer, i was amazed that it survived, but not for long, anyways. so i moved on to try a fast diode across the primary, but backwards, to absorb the back-EMF. but it just cut away at the output significantly (from an 2 cm to less than 5mm). it got quite warm in the process too, for the few seconds it was on. i havent tried it yet, but would a diode in series with the power supply, mosfet, flyback, and ground work better? and give a place for the electricity to go? what would a capacitor across the primary do? i heard people doing this and increasing the output, but will it impair an audio signal?

Question by -max- 7 years ago  |  last reply 7 years ago


What size should i make my copper coil for the size of my magnets!?

Hello fellow people. i am about to make some copper coils to use to create electrcity when i pass my magnets. i am new to this are of work and this is a home project for myself, any information would help greatly, and also some links to youtube videos that are very clear o understand as im not the 'quick' with things i dont understand. so.... i am using 25mm x 10mm x 3mm (lengh/width/depth) neodymuim magnets, rectangular shape, and im using 2mm insulated copper wire. i have purchased 30 of these magnets and am planning to stack them in sets of 4, and have six sets, and idealy make six coils for the magnets to pass, the coils being stationary and the magnets on a peice of wood that rotates via a pully. what size should i make my coils? i understand my coils inside diamiter should be the same size as the longest part of my magnet, ie;25mm, but how wide should my coil be? thats the bit that eludes me, i have added a picture to try help my explanation if this helps, thanks in advance for any information that you can give.

Question by MAR5HM3LL0W 3 years ago  |  last reply 3 years ago


5.5v DC supply on a 12v LED ?

Hi thanks for reading. I'm building (from the ground up) a set of 3x6" > Amplified 3 watt stereo Planar full-range speakers to be powered from a Cell Phone. I have most of the required parts which are many. One of the parts of the system I'm installing is a Blue LED (Amp On) Indicator. I'm running the system from a USB Charger or a Cell Phone USB Port at 5.5 volts. I went forward and ordered the Blue LED's and they haven't arrived yet so I can't test. These LED's are from E bay with little info of course. They are said to be standard, Blue 2mm 12 volt LED's. (Not Ultrabright)  ------------------------------------------------------------------------------------------------------- My question to you who may know: Are (Rated) 12 volt LED's likely to light from a 5.5 volt power supply? I guess my confusion is between the 12v claim and the LED Color Standards for a Blue LED.. ------------------------------------------------------------------------------------------------------- Without knowing the complete situation, here is the resistor value I've been able to come up with based on *LED Color Standards (Blue) and Supplied Power (5.5v): (*Blue) LED calculator: Current limiting resistor value: Source voltage = 5.5v LED voltage drop = *3.5 LED forward current = *20mA (=) Current-limiting resistor needs to drop 2 Volts. The resistor value is 100 Ohms, the next higher standard value resistor is 120 Ohm. The resistor will have to dissipate 0.04 Watts, the resistor should be rated 0.067 Watts, a 1/8 Watt resistor should do it. Final: 120 Ohm, 1/8 Watt. (color code: brown red brown, Silver). (100 Ohm: Brown, Black, Brown, Gold). ------------------------------------------------------------------------------------------------------- Thanks for the help! I hope I made some sense here ;)

Topic by Rexrich 3 years ago  |  last reply 3 years ago


Macro lens attachments

I recently got a set of marco lenses for my DSLR, an old E300. They are the simple kind, basically a magnifying lens that screws onto the the existing lens system like a filter. My first impressions of this simple and relatively cheap alternative to a dedicated macro lens in the 400$ range were quite good. But I also found some downsides and would like to know if they are a general thing to accept or a result of poor quality standards. 1. Although about 20% of the lens are unused (nothing at all visible when covering the outsides of the lens) there is some nocticable distortion happening. Especially the corner areas of the image when the object fills the entire picture appear to be slightly bend. Is that due to the marcro lens being a single and cheap system or a general thing with these marcro filter lenses? 2. It is quite hard to to get a clear focus even with F22 settings and good light. With the X4 lens it is not too bad and leaves about 8mm of totally sharp image before it gets blurry. But when using the X10 lens I often have troubles getting a sharp image of an object that goes less than 5mm into the background. Using a smaller setting, like f11 and only 1-2mm of the image is clear and sharp while everything in front or in the back of this area gets more and more blurry. Is this due to the marco lens affecting the focus? For example taking a full size shot of a rose flower is next to impossible if the entire flower should be be sharp - I would like to be able to get at least 10mm of totally sharp image when using f22 settings :( If this is a downside of cheap filter lenses then I already learned my lesson, but would like to know a bit more before saving money on a dedicated macro lens that I will rarly use...

Topic by Downunder35m 4 years ago  |  last reply 3 years ago


Is oogoo (DIY Silicone Putty) Oven-safe?

Hello! I have a question for people who use oogoo, or generally DIY silicone molding putty made from 100% silicone caulk. I want to cast oogoo molds of lego bionicle masks with polymer clay, but my issue is I need to keep the clay inside the mold in order to prevent any kind of warping, as most of it is spread a little thin (1-2mm thickness) and I don't want to end up warping it even in the slightest. Is oogoo or cured 100% silicone caulk oven-safe as long as it's within the specified temperature range? (I already know most DIY silicone putties aren't food-grade.) The silicone caulk I'm using is GE all purpose silicone I, mixed with corn starch, acrylic paint, and baby oil. The back of the tube says that it should not be used on surfaces that will exceed 400F/205C. The polymer clay I plan on using is cured at 110C, so I don't think it'll be a problem, but I'm worried exposing the silicone caulk mold to high temperatures will cause it to release some harmful chemical compounds. I looked up an MSDS sheet for GE silicone, and they had a generalized one stating exceeding the maximum temperature will cause the release of formaldehyde. Since I plan on baking these in our kitchen oven, I wouldn't want harmful chemicals contaminating a space where we cook our food. Also, if baking isn't an option, since the polymer clay is spread thin, and cures close to 100C, would curing it in boiling water be an option? (That way any water soluble chemicals would remain contained while the clay hardens.) All help is appreciated!

Topic by SixFootBlue 4 years ago  |  last reply 1 year ago


9kV 50mA tesla coil NST question. Why does the circuit breaker in my home trip when i plug in my NST?

Please someone help, this is my first tesla coil project, my setup: 230VAC 50Hz input ricci 9000v 50ma NST with a built in GFI (ground fault interrupter) but i bypassed the gfi succesfully .see pics safety gap  7,5 cm diameter pvc secondary 1000 turns #24 magnetwire (0,5mm) secondary 10 turns 8mm copper pipe primary (tapped at 7 turns) saltwater capacitor 16 green beer bottles in a bucket with a capacitance of 0,0122 uF or 12,2 nF (thegeekgroup bucket cap) static spark gap 28mm diameter stainless steel spheres as electrodes with oven fan (temporary, i am building a hyperbaric gap) 10cmx27,5cm aluminum toroid topload with a brass screw as breakout point RF ground aluminum rod 1,2 meter  When i tested the coil for the first time the spark gap was set on 6mm and i got 20cm or 8inch streamers without breakout point but the gfi on my nst tripped after a few seconds. i didn't know there was a built in gfi on my nst so i fooled around with my spark gap and safety gap and the tapping point on the primary hoping to get better performance. after a few runs the gfi started to trip very fast and i could only run the coil with the spark gap set on max 2mm, any bigger then that would trip the gfi on the nst. so i found out that it had a gfi and i bypassed it with thick wire. Then when i ran the nst i got the exact same thing but with my circuit breaker in my home. i have made a video on youtube that shows the problem here is the link: (please help) http://www.youtube.com/watch?v=piH44ohowyE please anyone help me! Any help or suggestion is very welkom!

Question by colinbarnes 7 years ago  |  last reply 3 years ago


Can a cracked guitar neck be fixed?

Hi, I finally signed to Instructables. :) My colleague is a big DIY guy and that's how I came across Instructables. Today, while searching for something I came across homemade recipes for musical instruments and that really hooked me on. Especially the one on turning an 6-string acoustic to bass acc. :) I had tried learning the guitar but didn't want to spend too much on the instrument, so I bought a second hand one from a garage sale (proceeds were for the city's stray dogs - so for me it was a bit of a win-win...almost :) ) What I realised much later is that: 1) The wood under two of the tuners (on the under/ventral side of the guitar) has splinters 2) One of these tuners has lost a fastening screw because the hole in the wood has widened and splintered a bit 3) the base of neck, just before the curve block that connects to the box, has a 1-2mm crack running across it (horizontally) Question is, can these issues be fixed so that a beginner like myself or someone who really doesnt have the money to own a guitar but wants to learn can still use it for some time? I never found the time to go to a music shop to have it checked. I also feel they will probably turn me away because they are more interested in selling guitars than fixing them. I really dont want to just throw it away. Second hand it may be, it just doesn't feel right... Your inputs would be greatly appreciated. Thanks! P.S.: Am at work right now but I will try and post images of the guitar as soon as I can. I had taken photographs of it a looong time ago. As a result, tuning goes off every now and again. On a colder day, tension increases and the crack widens. Update: Terribly sorry for the delay in uploading the pictures. I had a set that I had taken a year or so ago but I seem to have deleted them. Just got some time off work, here are the pictures. The crack, which I had earlier described as horizontal, is in fact, vertical. So much for my memory...

Topic by aristarkhos 7 years ago  |  last reply 2 years ago


123D Design tutorial for technical parts with accurate dimensions?

I'm an engineer with ~7 years of experience using Solidworks (professional CAD software). After hearing about Autodesk 123D Design here on Instructables, I tried to start using it to design and print things with my home 3D printer. However, I'm initially finding it very frustrating to use (more detail on that in a minute) - and I'm not sure if this is just because I'm stuck in my ways with the software I'm used to, or if I'm just trying to use 123D for something it wasn't really intended for. To try and give some concrete examples - I understand that you can create 3D shape primitives (rectangular prisms, cylinders etc) and assign them dimensions when you create them. I also understand that you can create 2D sketch objects and define their dimensions. What I don't find intuitive at all is how you can assign the dimensions of objects relative to each other. For example, say I want to make a 10x10x1mm bracket, with two 2mm diameter circular holes that have their positions on the face defined by the distance from their centers to the edge of the bracket. In a parametric CAD program, that is very easy to do in a 2D sketch and then extrude to a 3D solid. In 123D, I understand that I can create a rectangle primitive and then put holes in it using cylinder primitives - but it seems impossible to define the exact location of those cylinders relative to the edges of the rectangle; also impossible to create a sketch with two circles in it and a dimension defining the distance between their centers. To give another concrete example: at the 4:20 mark in this video (from this Instructable), he draws a circle on top of an existing rectangular part, and then "centers" it by just dragging it around freehand and eyeballing it. Would it be possible to define the center of that circle relative to an edge, corner, or center of that existing rectangle? Or can 123D just not do that? What I'd like to see, if anyone is up for it, is a step-by-step tutorial (preferably in video format) for making some sort of "technical" part where the dimensions matter and it isn't sufficient to just eyeball it and drag things around. e.g. a bracket like this (exact dimensions don't have to be what I drew here, but you get the idea). All of the tutorials I've seen so far - including the official Autodesk ones - seem to just focus on eyeballing it/free-handing dragging parts around.

Topic by Ben Finio 5 years ago  |  last reply 2 years ago


Fighting with Nylon ;)

As some might know I still use an old Gen1 Prusa but love the challenge of basically getting everything done with that oldie. One of my latest challenges of "always" printing on a cold bed includes Nylon. If you ever had troubles because you ABS or PLA filament got too moist you will already know what happens to your print... Nylon is even worse when it comes to moisture as you can't see or really feel it. I was thinking of making a complete Nylon guide as an Instructable but think I will start here to kick off some discussion first. So, we know the Nylon must be really dry for a god print as otherwise we get bubbles, bad adhesion and of course a foamy looking print. Well, not really... Let me explain: A perfectly smooth and shiny finnish is not always required, and with the right settings Nylon still forms strong bonds even with a foamy look. However, the dimensions of parts are affected as well - outside dimensions go bigger and hole diameters smaller. If that is no issue for your print then there is no real need to perfectly dry your filament ;) Speaking of drying: People use all sorts of methods to dry their filament, not just Nylon. One of the most common and most expensive seems to be the use of your oven for several hours to dry it. Another way involves food dyhydrators, bit less on the energy bill but still... Then we have the smart guys using the sun and silaca gel for the drying - good and great but so useless in cold and wet climates... My advise here: Take your time! I mean, sure you want to print right after the filament arrived in your letter box but a bit of preperation will save you filament and frustration. Usually filament comes in a sealed bag with a pack of silica gel and it should be dry and ready to use. But Nylon can become too moist within the time it takes to finnish a long print if you are in a wet climate. This means you start printing and all is good but the next day your new print looks ugly as for no real reason. Make use of these sealed storage containers. Put the filament in there with a good amount of indicating silica gel and only have a hole to feed the filament through - if in doubt use a bowden fitting and a short lenght of teflon tube to prevent friction. A piece of sticky tape over the hole when you don't use the filament and the filament is always ready to use. Reminds me to make an Ible for a suitable storage solution with spool holder... Anyway... When it finally comes to print Nylon you should know cardboard works best as a bed as Nylon sticks really well to it. I glue mine onto a layer of masking tape, this way it won't lift from the bed and I can still replace it very easy. But the most common mistake with Nylon is to print it too fast. The stuff really expands and shrinks a lot from filament to print and high speeds only too often cause the layers to seperate later on. Some people compensate with higher temperatures but I don't like the idea of fitting a filter system with activated carbon filters... Also keep in mind the intense shrinkage when setting the extrusion multiplier! If your ABS prints fine with 0.85 you can expect that the same sized Nylon prints fine somewhere in the range of 55-60! Now you also know why printing with thick layers is not such a great idea if you require all dimensions to fit. Although only outside accuracy can be done by cheating in the settings, getting outside, inside and extrusion widths settings accurate is almost rocket sience ;) Nylon is expensive or not available here in the diameter I require.... I had the same trouble and reverted to trimmer line and a modified, dedicated hotend instead. Why dedicated you wonder? Nylon can be real pain to clean as nothing dissolves and if you heat the parts hot enough to melt it you can not work easy with them. Having a decicated hotend means you won't run into the problem of burnt ABS or PLA clogging the nozzle ;) It also means you can match the hotend to the trimmer line you choice (more on that in a minute). For example, in some areas trimmer line of 2mm or 3.3mm diameter is the most popular and cheapest. Just drill out the hotend to cater for the new diameter, which I did after noticing the filament got stuck in the neck of the cold end ;) Trimmer line - does it matter which one? It does these days! Avoid everything that is not round or labeled with terms like "duracore", "dual core", "multi layer"  -basically all that indicates it is not just a single, solid stand of Nylon. Long lasting, special core line is great for your lawn trimmer but really bad for your hotend! PET, High temp nylon or even fibre re-inforced cores are in use, so in the best case you mix the nylon with overheating PET, in the worst you block your nozzle permanently. If it looks like it has a core or some sort of "mantle" around it, it means not usable.

Topic by Downunder35m 3 years ago  |  last reply 3 years ago


Looking for a cheap compressor with a high pressure rating or for airbrush use?

Today a friend of mine asked me if I know a way to reduce the noise level of his compressor in the work shed. With the current heat he prefers to work in the evening and nights, which does not make his neighbours too happy. His main use for several airbrush guns and sometimes for mormal airtools or the big spray gun for an undercoat or similar. So his main concern is oil in the airline and the actual flow rate is of second concern as he has an old 25kg propane cyclinder as an additional air tank. For relative low air volumes I would suggest an old fridge compressor. With a thicker pipe at the outlet that is filled with stainless steel wool most of the oil stays in the compressor. That is if this pipe is a) long enough b) upright c) of sufficient diameter so there is enough for the oil to avoid it being pushed up A second, standard oil seperator will be enough for the oil level required for airbrush stuff - and most other things too. If there is no pressure regulator on the airbrush system it is best to add a small air tank and shut off valve for it. In our case however a fridge compressor would be just enough to keep the bigger airbrush gun running but not to fill the tank at the same time. Not to mention the problem of fluctuating pressure levels. Since we already had a tank and pressure shut off connected to the loud compressor it was only a matter of finding something that keeps the neighbours happy. The first thing we did was to check how often the compressor comes on and how long it runs till the tank is back to pressure. With that and the stated air volume on the compressor we guesstimated that something a bit bigger than the compressor of a window airconditioner should be sufficient. The search begins.... If you don't know what to look for I give you a few hints: Older airconditioners often run on R22 or R12 - both use quite high system pressures which is a bonus, but more on that later. As a rule of thumb for these compressors you cans say: the bigger the higher the flow rate. At the local wreckers and scrap yards we found a few units but noticed the bigger ones often used three phases and not just one :( So we opted for the R22 compressor of a 4.5kW unit. Keep in mind the 4.5kW is for the entire system, so the quite massive fans can be removed from the sum. Usually the compressor alone is the 2.5 - 3kW range. Ok, we found the big thing but how does this help us? First things first ;) The oil was removed as the housing stating the original oil amount. This allowed us to use an oil rated for air use that has little to no water absorption qualities - you don't want water in your compressor. With the usual heat the water should be no problem anyway. Next was a pressure test to make sure the thing actually still works, so we added some plumping in the form of standard connectors to the inlet and outlet. We got well above 200PSI and abondoned the test at this stage as it was more than enough already. The air volume seemd to be well more than expected too so let'S move to the next stage. A fridge or aircon compressor always needs to have a certain amount of oil in it as it will otherwise seize and overheat quickly. But they are also designed so that the oil mixes with the refrigerant to cool all moving parts. So the biggest hurdle is to make sure the oil stays where it should stay and won't enter or get lost in the tank. Only real option for this to use something to catch the oil that is capable of releasing it into the compressor once it shuts off. Now there are several options for this so I start with the most basic: A "catch can" will get most of the oil, especially if filled with stainless steel wool or similar. Downside is that you have to find a way to get it back into the compressor. A step better is a thicker pipe filled with stainless steel wool to catch the oil. If placed upright and the outgoing pipe can be bend a bit upwards you have a good chance that most of the oil will sweep through the valves and get back down into the compressor housing. But only too often the cheap or even free compressor is better than expected and the oil won't get back into the housing as the vlaves are just too good. The last and IMHO best option is a pressurised return system. Most compressors for bigger aircons have a seperate filling port or sealed off piece of pipe. In this case you can do a simple check to see if they are usable for our purposes. Open the port of pipe and use a simple bike bump or similar to get some pressure in it. With a dedicated oil filling port you are best off but they are hard to find. The air you pump in should come out of the high pressure side - you might need a little pressure to overcome the valves. If you hear any bubbling in the housing (use a pipe on your ear or a sensitive microphone) it means you are going through the oil inside the compressor - perfect! You might not hear any bubbling but the port or pipe is still usable. Get ready with your fingers and start the compressor. The fill pipe should be sucking air in, same for the service port if there is one. A dedicated oil port should not suck but instead force some oil up if you cover the high pressure outlet. I assume all is good and no oil is splashing out of the open pipe or port. Add a small amount of oil with a syringe or similar into the port/pipe. If you see an oil mist coming out of the high side it is bad news. Clean outlet air is good. To get the oil back from the catch pipe or can we have to add a hose or pipe with a needle valve. It needs to be adjusted so that there is only a very little airflow (or oil mist) coming out. This regulated outlet is now being connect to the port/pipe with a bit of suction that we found earlier. Now every time the compressor runs the collected oil is forced back into the compressor :) Please double check the port/pipe used is not directly connected to the intake port! The last thing you want is a puddle of oil going into the cylinder and damaging it! They are designed to move gas but not liquid! If in doubt use a hardened sttel nail or similar to create a small puncture in the top of the compressor housing if there is nothing else to use. Check first if the material sound very thick, if so it might help to drill with a 5 or 6mm drill first - only about 1mm to make sure you won't enter the housing and conimate it with metal shavings! Once you have a small puncture hole of about 2mm in diameter get some 2 component metal repair glue mix and add a suitable connection for the collecting pipe/can. If you feel up to it you can of course use a blow torch and solder the connection on. Now we have the compressor working with a oil return system that also gives up very little to no oil at all in our system. You might now think you are good to go but you should at least add a decent and fine filter to the air inlet ;) The compressor noise of a bigger system can still be an issue if thicker pipes are used that allow the noise to travel out. Keep in mind they usually run in a fully closed system.... As we only need to match the noise level of the compressor itself a solid steel can like an old fire extinguisher in the 1kg rage is a good way out. Fill it with filter wool and a fine filter pad after adding some hose connectors either end. You can misuse the trigger nozzle and keep it to seal the top if you braze a connector on it. If the intake here is about 5 times larger than the pipe connection to the compressor itself the air flow going into the thing is low enough for a cheap paper air filter can or box if you have a quite dusty enviroment to work with. The real trick is to have a hose or pipe on the inside of the fire extinguisher connected to the compressor pipe connection. A garden hose is great here as is reduces the noise quite good and is dirt cheap. Make a lot of about 2mm sized holes in this pipe and close the other end of it off. Now the compressor will suck it through the small holes and the soft garden hose reduces the noise, the surrounding padding brings it down to basically nothing. The special case of clean air for airbrush.... If you read this for the sole purpose of airbrush use then this chapter is just for you, all other might want to skip it. The two things you don't want to enter your gun is oil or water. Both are a common thing in normal compressors due to lubrication and pressure difference resulting in condensation of the humidity in the intake air. Oil free compressors of good quality can cost quite a few bucks and often require ongoing replacement of membranes or piston seals. A refrigeration compressor with the above modifications already provides clean enough air for most airbrush users if a proper tank is used to store enough of the compressed air. So you might just want to add a basic oil filter or very fine paper filter close to the regulator. For very detailed work with very sensitive paints you might want to build a filter box containing of several layers of oil absorbent paper. This stuff is often used in the industry to clean up minor oil spills and bind oil very well. A PVC pipe (pressure rated please) with 5-8 layers of filter screens should last about a lifetime before the filters need changing if the diameter is in the 10-15cm range. That leaves us with the dreaded problem of condensation and water contamination. Depending on the type of paint and gun used a small amount of water vapour is usually no problem. Solvent based paints usally show their disliking by unwanted drops or run offs caused by water droplets. Of course you just go and buy a professional dehumidifier and accept the ongoing replacement costs for the cartridges... But if you are in a climated that has above 30% humidity for most of the year than you will have to remove the water one way or the other. A big enough storage tank for the air that is upright usually helps to release any condensated water prior to usage. But if you use a homemade tank you might want to avoid this problem completely and forget about water in the system altogehter. Silaca gel is the answer here, specifically the indicating variety that changes color once "full". A spaghetti glas or similar should be big enough unless you are in a very humid climate - is so just use multiple in a row. The air intake side for the compressor has to go through the silica gel to be effictive. This mean we need two holes in the lid. One with a pipe or hose going all the way to the botom - that is the air intake side. The other right on the lid - this is the air outlet side which continues to the compressor intake. With the color change in the silica gel we can estimate how much usage we have left until we have to heat it up to remove the water. If this color change happens quite fast from the bottom to the top, let's say within three days or less than you really need to use more jars with silica gel in a row or a longer one - like using a long and clear acrylic pipe instead. Of course you can always just cut holes and "viewing glasses" along the length to a PVC pipe.... No matter how wet your climate is you want to get at least 100 hours of compressor run time before you need to recharge the silica gel. This brings us to the recharging.... Once the color changes and you only have about one quarter left to the top you want to get the water out of the gel and re-use it. To do this you simply heat it up in your oven to around 120-150°C - the supplier should state the max temp for this. If you use a gas oven or one with limited accuracy here it is best to stay within the 120° range. You need to stir and mix the gel or use something big enough like an oven tray. But be aware that these little balls are like glass! The roll and bounce like no tomorrow! IMHO it best to use an old cooking pot that has no plastic handles for this and not to overfill it. This allows for easy mixing without making a mess that might cause a bad trpping hazard on your kitchen floor tiles! Once the gel is back to original colr it is time to let it cool of to a safe temperature and to fill it back into our canister or pipe. Tanks and shut off systems.... We have a refrigeration compressor working for us, and since it was for R22 we can use much higher pressures as a simple compressor from the hardware store. The low pressure side is used to 70PSI or around 5Bar of pressure in normal working conditions. The high side often works at pressure in the range of 200-300PSI or 14-20Bar! The tank we used is a big propane tank that was restamped at some stage in his life for the use of LPG - so it was tested to quite high pressures. The lower pressure limit is what keeps the stored gas liquid at the given temperature. For Propane at an imaginary 30°C this would around 155PSI or 10Bar. The stamped test pressure, although outdated, showed 600PSI or around 40Bar of pressure with no problems - and the thing was thick in the walls... The old shut off switch from an old air compressor was adjustable after removing the safety cap with a bit of force and the help of few cold beer. With a little tank attached we adjusted it to turn the compressor off at 250PSI or around 17Bar of pressure. If your tank is old or has no test pressure stamped on do your own test in a safe location. Make sure the area is secured so there is no chance of debris from a brusting tank can go anywhere - this includes to chain down the tank itself ;) Use the aircon compressor to fill it up to 300PSI or 20Bar of pressure - this should be tolerated with ease by any propane or LPG tank. Shut the valves and let it rest for a day or so. It is best to do this in the early morning so the heat from the day will slightly increase the pressure. At the end you still want to have a working tank and no major pressure losses. All of our mods on this tank were done without actually harming the tank. This was possible as the original valve had a release port for filling purposes - as it standard on most refillable ones. Here we removed the valve and added a pressure guage instead - better to know what is happening than to assume things. As this "port" had a seperate connection to the bottom of the brass valve we added as T-connection to allow for the connection to the compressor. Just be be really sure a thin piece of copper tubing was brazed to the exit hole of this port so all incoming air will be going down and away from the outlet connection with the big shut off valve on top - which we use to actually isolate and close the tank when not it use. Last thing required was something to connect the pressure shut off switch and regulator to. That was the only major expense on this project as we had no old BBQ hose or similar to get a suitable connector to the tank. We bought a simple adapter for the use of smaller hoses and cut the unwanted bits off we there was only the bottle conntector with the nut left. After removing the rubber ring we brazed piece of copper pipe onto it. Here we drilled holes and fitted severy connectors. First for the pressure switch, then for the connection to the pressure regulator and two standard ones with a ball valve for air hose connections. One air hose connection female, the other male so a standard compressor can be connected as well or "backfilled" for additional and mobile storage use. As we wanted to avoid any reduction in the safety and burst pressure no release valve was added at the bottom on the tank. The added silica gel filter stage was used instead so no water will get into the system to begin with. Additionally, and painfully for me and me friend, the inside of the tank was coated with a layer of acrylic paint to prevent and rust as it was free from it when we checked it at the beginning. This involved filling a suitable amount of paint into it, closing the top while keeping the thread clean and then to move the tank around to cover the inside evenly. If you do this be prepared for some weird movements with your friends LOL Once we were sure all ust be covered by paint at least three times we released the exxess paint and allowed the inside to dry with the assistance of some air forced to go in with a length of pipe. This was repeated 3 times... Then another two just for the bottom third of it where there might be some moisture after all... Now you don't want to remove the brass valve with everything connected to it just to turn the tank over to releae the collected water. Instead we made sure the added pipe on the former relese port would go all the way to the bottom of the tank. If any water collection is suspected only the connection to the compressor needs an additional valve for the disconnection so the water will be force back out here. To make this easy and fast we used standard quick connectors and a piece of flexible airhose rated to 20bar of pressure for the connection to the compressor. We checked the performance of the moisture removal and oil removal only for a few hours of running time while priming some surface for later use. The compressor oil used was very smelly to say it nice but nothing coul be smelled in the first paper filter after the pressure regulator. To check for remaining moisture levels (65% humidity in the house) we used a 10m length of clear PVC tubing going through an ice bath. After 30 minutes of moderate air release there was no condensation on the inside of the tubing visible. Of course if you only need it for air supply and don't care about a bit of moisture and oil you can keep it simple ;) Benefits of doing such a stupid thing: For starters noise and the peace of mind that you can do a lot of airbrushing until the compressor needs to kick in again. Then of course the benefit of an almost silent system compared to a standard compressor - something you can actually tolerate while doing art. But the real deal is knowing YOU did it and you did it for cheap. Warnings and some advise... I know, it should be at the very beginning but I just hope you read till the end ;) If the compressor fails from overheating you are up for a new one. This means the tan size should be within the limits of what the compressor can handle - same for what you actually use on air. You want an empty tank to be filled before the compressor feels hot to touch - quite warm is fine but if you can't leave your hand on it then it is too hot. Same story for the usage. There is no point in using a tiny 10 liter storage tank if you need that capacity every few minutes. The compressor would only have little pauses and overheat quickly. You want a good balance of usage time before the tank goes below supply pressure and running time of the compressor to get it to full pressure again. This brings us to the safety of high pressures. Where possible only copper tubing or sufficiently rate hoses should be used, the later as short as possible to avoid them acting like a whip if something goes wrong. When it comes to the safety of the tank you want to make sure to stay withing it's rated limits. All benefits of a compressor capable of producing over 500PSI otr close to 35Bar is wasted if your tank and pressure regulator can't handle it. This must not mean that you try to use a gas cylinder of unknow age and pressure rating and assume it will work! If in doubt use a lower shut off pressure and stay within the limits of normal air compressors - which is around 120PSI or 8Bar. Never, ever use a tank that is compromised by inside rust or bad corrosion on the outside! If you don't know how to braze copper tubing, pipes and connectors then check out some of the great Instructables about it! Whenever you know you won't use any compressed air for more than a few hours close all valves especially the ones going back to the compressor on the high pressure side! Some compressors really don't like a huge pressure difference constantly pushing on the reed valves. If your tank is big enough to allow for more than one hour of operation before the compressor has to top it up you might want to consider a one way valve right on the compressor outlet. This will prevent any massive pressures going onto the valves - especially helpful for modern compressors that only rely on the sealing capabilities of the clyinders or rotary system used. One thing you should always consider is a pressure relief valve rated for about 50PSI more than your tank pressure - it can be added to the pipe ;) If the shut off valve ever fails the relief valve gives you the ease of mind that it will blow before your tank does. Maintenance... If modded correctly the compressor should stay in the compressor and the compressor itself should not overheat from use. Having said that your compressor might force out a little more than your best catch system can handle. If that becomes a problem it might help to use an oil with a lower viscosity. If all fails it just means you need to top up oil once the last last paper filter is filthy or use slightly more to begin with so the intervals are longer. The silica gel, if used should be recharged before all of it is wasted - no point in adding it if you use it once full of water. If no gel is used there will be water in the storage tank. Even with the added paint and a good air filter it is possible that nasty things grow in there. Making sure the tank is emptied of any water after long uses and again before the next use is good practise. If no pressure gauge is used on the tank you must make sure the shut off valve is always working fine and within set parameters. I strongly recommend using a gauge and if not to perform a pressure check of the system every now and then to confirm all is within parameters of normal operation. A compressor constantly running means you either use far too much air or you have a leak - same story if the compressos kicks in after some of forgetting to shut it off and close the valves. If you keep the above in mind the salvaged compressor should work just fine for many years to come. Troubleshooting and alternatives.... You put everything together the right way, double checked and something is till not right? Maybe my crystal ball helps me to find something... 1. Always oil coming through the catch system. It usually means you use too much of it. A salvaged compressor, if the refrigent was removed legally from the system should still have a "correct" level of oil inside. Too much oil would mean is being pumped through the system at an excessive rate. Very thin compressor oils tend to do that in the compressor is misude like we do. Changing to standard mineral oil can help here. As a last resort you can use a pressure gauge or good judgement to allow more flow through the needle valve from the catch system back to the compressor. Too much backflow here would mean we loose system pressure to the set level of this needle valve! 2. The R22 rated compressor seems to be unable to produce enough pressure. First do a leak test using soapy water to rule out any leaks. Do a back pressure test on the ports. If you can push air through them in the reverse way with ease it means the valves are damaged making the compressor useless. You need to replace it. A regular cause with our type of usage is a constand back pressure from the storage tank to the compressor. To prevent this it might help to mount an electric solenoid between the compressor and storage tank. Such valve should be off when the pressure switch is engaged and on when the pressure switch is disengaged. This prevents the coil from overheating but requires a "normally off" type of valve. A good source at the wreckers are cars with LPG systems installed, they usually have suitable 12V valves somewhere on or near the tank and filler cap. 3. I am using several kg of silica gel but still get a lot of water in my storage tank. Going overboard in a humid climate can be a good thing here but if moisture makes it into the tank even with great amounts of silica gel there are only two causes: a) the tube or cylinder used is not long enough or not wide enough to allow the absorption of all the moisture going through. b) the flow rate is too high and the temperatures are too. For the first the solution is obvious enough. The second is related to the first for the diameter and lenght but temperatures constantly above the 30°C while operating somehow limits what the gel can do. Using a cooling coil on the intake side or simply putting the gel containers in icy water will help to a great deal here. If that is not an option than I suggest to layer the gel and to seperate it with fine paper filter screens. This will slow and even out the airflow allowing for more contact time with the gel. 4. The compressor gets very noisy after some time. If "some time" means more than 30-45 minutes you simply have it running too much and it overheats. If the noise increases too much when reaching the shut off pressure it can mean the pressure is too high for it. 5. Can I use multiple compressors from smaller units or refrigerators to get enough air volume? Of course you can but it might mean you have to lower your pressure expectations. Consider that each individual compressor would get the back pressure from all other compressors running while it's outlet valve is closed. To avoid premature failure you want to make sure the compressors are shut off at a lowver pressure. 6. I don't want to use a big tank but require a good airflow for airbrush. Two or three fridge compressors working one after the other with a small tank to keep the output pressure even can allow for about 30 minutes runtime per compressor. With three it gives one hour for the the first to cool off and should be enough for ongoing work. Downside is you need to make some sort of automatic switch to "rotate" to compressor working. Last words.... Is you find any spelling mistakes you can keep them. However, if you use them in any way to make a profit with them I kindly ask for 10% of your earning from it ;) Why did I not make an Instructable out of all this? Well the day was very hot, the beer very cold and my mobile phone at home, so I did not take any pics. To top it up the whole thing is now in a seperate box for additional noise reduction so it can be used in the same room where the guy is working. Of course he just used a nailgun for the job without any regard of access or at least easy view of the two pressure gauges. Typical if you have a great idea and the cold beer tells you to forget all about screws or hinges ROFL Only comment was: You created it and it works fine, why would need more than the pipe connections for the gel and regulator? Maybe he will reconsider when the service is due....

Topic by Downunder35m 2 years ago  |  last reply 2 years ago