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Other uses for a Caramel Wheel....

I had to clean up large sized decals that used a 3M adhesive.Instead of filtering the solvent fumes with my lungs I decided to listen to the guy in the hardware store that suggested to use a Caramel Wheel instead.Have to say I was very sceptical...Ever had this extra heavy duty 3M tape to get off again??No matter what you try it is a battle of will and endurance...To my surprise using the Caramel Wheel was like using a big eraser on paper.The things rubs over the surface, takes the goo off and leaves a totally clean and stick free surface.What otherwise took me at least a full hour was done in under 10 minutes - great...Once done with the hard work I examined the now well used up wheel.Does not really work as a proper eraser for a pencil as the rubber is much harder.Does not even scratch galvanised surfaces.Does not like it at all to be used on wet surfaces :(It is not just rubber in a fully solid form, more like flaky bits stuck together.First misuse I tried was polishing a piece of acrylic plastic.A cloth or similar always soaks up a lot of the polishing compound, which makes the process costly.Friction was a real issue at first because the wheel just had no grip at all.But on hindsight it helped to spread the compound fine and evenly.When it started to grab I noticed two things.a) The plastic warms up quickly.b) It polishes really good.Downside is that you need a low speed and very little pressure, too much of either and you risk stripping off the surface.Second misuse was on my knife.It is old, it is abused, it is loved tool I prefer, so it does not need to be razor sharp.The burr on the knife edge after sharpening should be removed.Usually I work my way up to 1000 grid, then use a leather strop.Not for this old knife though.In most cases the burr comes off with use.The Caramel Wheel had no problems removing the burr while leaving the edge sharp.And with a tiny bit of polishing paste applied it even managed to produce a extra sharp edge.Last misuse so far was to clean off old silicone from my bathroom tiles.Silicone does not like to stick to silicone!Means when you refurbish for example the silicone around your bathtub it never last long.Chemicals to remove the fine layer of silicone are harmful to say the least.I did not bother with the entire groove, just the outer parts where the new silicone needs to grab.First the wheel slips and slides off a lot but you see how it cleans the surface of the tiles.Then it starts to grab, indicating the tile is clean in this area.Won't do much in the grooves with the grouting though...What I really liked is that the wheel took off what you can't really see.The oily feeling when going over removed silicone was gone, just nice grippy tiles.

Topic by Downunder35m    |  last reply

Cannot reply to comments from you:comments: reply

This bug has been going on at least two or three weeks. When I get an email notification of a comment, and I hit the "reply" link in the email, it takes me to a web page with a valid-looking box for typing the comment. I type the comment, either in a browser or a smartphone browser, hit "post comment," and it vanishes - without a trace. No way of getting it back. This bug does not appear on other pages, just this one. So replying to comments directly from emails does not work.

Topic by susanrm    |  last reply

Cannot post comments or reply to questions

When I tried yesterday to post a comment, it displayed a message: " Oops, something went wrong! " Today, I tried to reply to someone's question, but it wouldn't work: " Oops, something went wrong! " He was able to post the question, but that was eight days ago. That means this glitch happened between now and then.

Topic by Techno_Bot01    |  last reply

My new instructable won't publish again

My latest instructable won't publish, I did everything the way I always have and I get this error message: Oops! We couldn't understand your request. Please contact us to tell us as much detail as possible about what you were trying to do when this happened. This is the second time this has happened to me, are other people having this problem? I have not changed anything on my system. Last time Seamster told me to send him a private message with the url, I am sending him another message with this url in it. Thank you JRV31  

Topic by JRV31    |  last reply

Error message while publishing Instructable

I was trying to publish an Instructable. The icon that says "Generating Image" was going, then this error message popped up: "Oops! We couldn't understand your request. Please contact us to tell us as much detail as possible about what you were trying to do when this happened."So, being an obedient citizen of, here are a list of details of what I was doing:-Publishing an Instructable into Outside, Camping, Creative Misuse Contest-Windows 10 with Microsoft Edge-The PC went to sleep sometime after all my photos finished importing, maybe severing a connection (I don't really know what I'm talking about, btw)-I had perfect internet connection to my knowledge after I woke up the PC and started on my InstructableHope this helps, Auf Wedersehen!____UPDATE____I immediately went back to my draft and tried again, and successfully published my Instructable. It must have been a small glitch or something, thanks for the help you didn't have time to give! :)

Topic by Thorondor95    |  last reply

how to fix elastic waistband that's too tight?

I have a circle skirt with a wide elastic waistband. Skirt is chiffon and waistband material is velour...I think. Awhile back I cut a hole in the waistband and then cut the elastic in the back and tied the two loose pieces together with string to give me more room but I need to fix that. I want to really fix it not have it tied together. I will doing it all by hand so I need easy solutions. I don't own a sewing machine. You can see that the waistband in the front is flat and in the back its all crooked and soft. that's where i cut it. I guess there's no 'support in there now. I showed the pictures of how I cut the waistband. So any ideas are welcome. get rid of elastic? attach more? use something else to connect it?...ok Thanks...

Question by surat108    |  last reply

Railbiking. Anyone built one?

I heard an interview today with author William Least Heat-Moon.  In his latest book, he meets a man who has built an outrigger bicycle he calls a "Railcycle", which he uses to ride on disused railroad tracks all over the world. Curious, I did some searching, and found a number of places on the web where people are talking about this, but they all seem outdated. Bentley Railbikes Railbike Tours Homebuilt Railbike Has anyone else heard of this practice?  Do you know of anyone currently making and riding such contraptions?  Do you have one of your own?

Topic by yoyology    |  last reply

Capacitor for DS1813+ Repair

I recently blew a capacitor on my DS1813+ and have no clue what value I can replace it with because I do not have schematic/wiring diagram.The unit seems to function without it,but I'd like to repair the broken part of it if I can.If everything working fine then you've got something here. It would be reasonable that :If it was a regular 0.1uF chip bypass capacitor,then they must have used an 0402 sized component like they have used elsewhere.

Topic by BintuGomes    |  last reply

Why does my RC transmitter/receiver work after removing this magnet?

The RC parts I've been tinkering with have a small electromagnetic coil. The radio frequency can be tuned by using a screwdriver to raise or lower the magnetic core.What puzzles me is that the transmitter and receiver will still work if the magnetic core is removed from both parts. This seems like an important component, so why does it work without it? What's happening to the radio frequency?Bonus question: What's the purpose of the capacitor on the receiver board?For context, I'm working on an RC car project for kids and I'm trying to figure out how to diversify the radio frequencies so more kids can operate their cars at the same time.Thanks for your help!

Question by LanceMakes    |  last reply

Hobby CNC router/engraver idea

I recently had to fix a friends (chinese) mini router.Long story short short: I realised that those things are only good for a small Dremel but not a real router.After looking up what is available in the tinker areas it seemed the only way out is the expensive way of using servo drives.Not really easy to handle either if you want some Arduino or Raspberry do the computing parts...So what would actually be required to make a cheap but still usable tabletop router that can handle 10mm playwood or work with (at least) Aluminium?In most if not all cases the tool will limit the movement speeds quite drastically.If neither makes any sense to force the rotating tool through the material, nor to make several high speed passes to get the results.Even when engraving stone or aluminium (dry) you can only do it so fast.The hobby market is full of Arduino or Raspberry based router projects but most, if not all use standard Nema motors for the positioning.As a lot came from the 3D printing area I guess it just made sense.And if you want to run servo drives or similar you won't control them with some cheap Arduino.Nema motors however suffer from the problem of limited torque at higher speeds.And using normal gearboxes only goes so far as the higher the reduction, the lower the resulting max speed will be.Means in the real world a Nema motor would struggle with any gearbox to get a reasonable speed to work with high loads.I think the way out could be to use external encoders for the positioning.Like on the early ink jet printers the slotted band attached to the printhead did.Or if you are old enough you still remember the mechanical mouse that stopped working once the code wheels were full of dust.The Idea came to me when servicing a geared motor for a 8-way valve.Just a cheap Mabuchi RS555 style motor and a planetary gear box.Together they produce a whopping 800nM of torque and literally no backlash at all on the output side.High resolution encoder wheels with sensor are available quite cheap as well.I did some very basic math on the accuracy side of things based on a table size of 1.2x1.2m.Using a chain drive we are looking at less than 1/2 mm using standard chains and below 1/10 of a mm using tight, precision chains.Going lead screw and heavy duty, high torque the accuracy is about the same as on a good 3D printer but the speed will be quite slow - I guesstimated around 3-4mm/s.A heavy duty belt drive system seems to be perfect as we can adjust the drive pulley size to match the gear ratio and speed requirements.Chains work fine as well here but usually mean a higher overall cost.The benefits are really high torque with more than reasonable speed is possible.The mechanics and electronics can be kept very simple.No high speed processor required, a simple 8-bit Arduino Mega will do fine.No expensive motor controllers, just a simple DC motor driver with PWM control.Extreme holding torque when an axis is not moving thanks to the gearbox.Code sensor can be driven by the belt or chain to get direct distance measurements.Downsides of the approach....The initial costs will be higher than standard Nema motor based solutions.To my knowledge there is no Open Source project for this kind of approach available (yet).With the heavy duty mechanics it won't be very portable, best to have it stationary mounted somewhere in the workshop.Quick reversing of the direction will require suitable DC motor drivers that can not only reverse the polarity but also provide the option for a break resistor to allow a fast stop of the motor without backfeeding generated electricity.Getting 3 dimensions would require a motorised table which can be a challenge if you need to support a loaf of weight and stay steady while a tool causes a lot of pushing in all sorts of directions.Probably a sissor lift system in all four corners would work best here.Happy tinkering! ;)And if the idea is already out and in use just forget about it LOL

Topic by Downunder35m  

Where do you get Salt Peter (potassium nitrate)????

Does any body know where to get Salt Peter (potassium nitrate) but not from uni's or from the internet?? If not how do u make it?

Topic by 10wellsmit    |  last reply

What's the most meaningful thing you've made as a “maker”?

It's a simple question, no it's not directly related to any field or topic, but I'm interested in your responses. What makes it so significant to you and why is it so important?I look forward to reading your replies

Topic by CamdenS5    |  last reply

OneDrive error 0x80070185 during migration from Dropbox to Onedrive

We are attempting to migrate from Dropbox to OneDrive across the organization Mac and PC. We are piloting with a few users and "Files on Demand" are a requirement. We are running into issues where accessing Office documents from the OneDrive folder (using windows explorer) causes an error 0x80070185. If on a PC, you can click "skip" and the file opens normally. On a Mac, you have to wait a few minutes for OneDrive for business to realize you want to access the file which means it synchronizes and then opens up normally. I have opened up a Support request in Office3 65 but it's obvious first line support has no clue what they are doing. Anyone else have this issue? I have seen other posts about this error with no resolution.Any help much appreciated.

Question by Akshay_M    |  last reply

USB OTG and Charging circuit question

I've got an old tablet (some unknown chinese brand with zero support) that has one microUSB port for charging and connecting external USB devices (known as OTG). But I'd like to do both. Found a cable that has the required connections but it doesn't work and I'm trying to understand why. mobdroI attached a device to the USB and attached charger, and the device was getting power, so VCC and ground are wired correctly. Connected USB device and tablet, and device was detected, so the OTG side is all good. But that means power is also flowing to the tablet from the charger. So connect charger and tablet, but not charging.I mean, it makes my brain hurt more thinking about why this does work with my phone. Power flowing from charger to USB, fine, but the phone is also providing power to the USB, also fine (parallel power. nothing odd here), AT THE SAME TIME IT IS RECEIVING POWER TO CHARGE!

Topic by ChinusGomes    |  last reply

Is it possible to make your own venetian blinds? Answered

I need custom-fit blinds for about 18 windows and to pay retail for that many of them, especially since I'd like to have higher quality than your basic white PVC blinds, it's going to be well into the thousands. So I'm wondering if somebody can explain how to make your own venetian blinds. I have some skill precision cutting wood and metal, so that part wouldn't be too difficult whether I chose to use wood or aluminum, but I think I would have a problem figuring out how to create the pulley system so the blinds will not only go up and down, but also open and close.  

Question by noahbody_    |  last reply

Non lethal poison blow darts???

Non lethal poison blow darts.? I was thinking about making blow darts then the topic struck me, could common natural non lethal poisons or toxins be used in blow darts. This sounds a bit vague, so heres and example: you take poison ivy leaves and either wipe the darts on the leaves or grind up the leaves then rub darts in the mix. Would this work, how effective would this be?. I am not planning on even attempting to try this, this is for informational purposes

Topic by HOMEPIE64    |  last reply

Very dark Cover photos

Can anyone please tell me why my cover photos for my new projects are coming out so dark. The quality of the photo is good, just not in the cover photo. Ruins the look of my project. How can I fix this please.

Question by AnitaH25    |  last reply

Your Instructable Failed to Save

I'm trying to edit mine Instructable ,but I will get error ,,Your Instructable Failed to Save" I delete all cookies , but this didn't solved a problem.

Question by RimvydasP    |  last reply

Batch Help(randomization)? Answered

Hello Im workin on a batch file and i would like to have help with with making Cmd randomize between two selected numbers Example: Random 1-10 Answer: 3

Question by Chromatica    |  last reply

how much power do i need to heat 20 awg nichrome wire?

Im using 2 9 volts and its not working

Question by G-force777    |  last reply

Laser Cutting in the Classroom

After creating a makerspace at my elementary school, I was always on the lookout for fresh projects and new tools and a laser cutter was that one big item at the top of my wishlist that I just never got... but, I know some teachers and librarians who are brand new to the world of laser cutting and would love pointers from other teachers who have already worked through some of the challenges of starting something new. :) So, if you have a laser cutter in your classroom or school makerspace, please share any tips or suggestions you might have for any teachers who are just starting out with one at their school. Also, feel free to share any cool projects you and your students have done or programs you use.

Topic by WeTeachThemSTEM    |  last reply

Connecting Peltier module using an Arduino

Hi Guys, I am a beginner to Arduino and I started building the circuit to control a Peltier using an Arduino following below article. I connected the circuit following the instructions and installed the phone App as well. but the circuit is not working. I tried connecting the Peltier to Arduino using a simple circuit and a p=12; void setup() { pinMode(p,OUTPUT); }void loop() { digitalWrite(p,HIGH); }In the circuit, I connected the positive (red wire) end of the Peltier to D12 of Nano Arduino board and the negative end( black wire) to the negative end of the 6V battery. Then I powered the Arduino board by connecting Vin(Arduino) and battery(+) using a jumper wire. The GND pin of the Arduino was connected to the battery(-) using a jumper wire.But still, the circuit is not working. Is it because of the lack of current provided by the Arduino to Peltier? Is there a way to make a circuit with Arduino and Peltier? If I connect the Peltier through a Motor driver does this work? If so please guide me on how to connect the motor driver to my circuit to make the circuit working.This is really an important project for me and due to lack of my knowledge in this domain, I'm struggling to figure out a way of making the circuit even after doing a lot of reading. If someone could support me, it would be a great help for me.

Question by Indee1985    |  last reply

If I made a small wind turbine how much power would that bad boy put out? It gets rather gusty here. Answered

I was working on my car yesterday and i noticed the doors getting blown closed constantly. I thought how might i turn this unconvenience into a convenience. Well since the price of everything is going up cutting some costs off the bills. Help please?

Question by CrawdadMan    |  last reply

Bluetooth module without arduino

I want to use bluetooth relay module without arduino , relay continuously energized until circuit turned off or else i turned off from mobile, and second thing if i turned off the bluetooth on mobile it does not affect on circuit

Topic by PrinceS104    |  last reply

Hurst model T motor

Hello my name is Freddy iam in New York DYI hobbiest and iam doing a table project that is a rotating workbench for different bench top tools to be used and it will rotate on this motor but my problem is how to power it.. I would like to plug it and later add a switch to it.. Any help would be greatly appreciated thank you for time and patience... Freddy Westchester New York/AKA YO

Question by FreddyS19    |  last reply

how can I make a wild rabbit house?

I wanted to find some free diy plans on making a portable, house for rabbits, that for wild rabbits that's designed so the rabbits will not need any matanince (because they are wild critters which do there own natural thing  so people do not have to disturb them,with access for emergency use. you can make your own project then post it just make sure it's safe for the rabbits and people, I don't want to spend too much money, It's just a possible plan it's not a garrentee   I disclaim I am a humane ethical young man, I am good at heart, I will see what I an do if nessary and get my parents concent, it is meant within the terms of use

Question by 35Timmy    |  last reply

Best Way to Learn Circuits?

Hi So long story short last year I switched into EE, and honestly really dig it so far! Due to my actual electrical course work requiring a different set of math classes than I originally had taken I haven’t been able to take any electrical engineering classes yet... I ended up purchasing some breadboards and parts to go with it, along with a raspberry pi to learn about building circuits and work on some coding as well. The goal is to mess around and learn what I can before I can take an actual circuits course, but from your experience what’re some of the best things I can do to build my knowledge in the field, or any advice on what I SHOULD be doing as well?

Topic by BushBond    |  last reply

What is a 1/4 watt resistor? Answered

Alright, So I know the basics about resistors and what-not, but as I was buying beginner supplies, I noticed there were resistors in OHMs and Watts, What's the difference between the two? And like, can the unit Watt be transfered into OHMs? And which one would I use when my general area of working would be around basic LED work and noob stuff like that xD?

Question by E D E N    |  last reply

Can I build an Electric motor that can self recharge it own power source? Continual self charging battery powered motor.

I just wondered, If you could take an electric motor like the ones that they use in the electric cars and motor bikes and by adding a generator/alternator ,or turbine to recharge your batteries as it is running. Like making an electric continual self charging battery powered motor.

Question by regdab    |  last reply

Getting Started

I'm looking to get started at wood-carving, and am wondering what I need to get to get started. What tools? and where to get them? What are good woods? What are good first-time projects? Thanks

Topic by sdfgeoff    |  last reply

Arduino Neopixel Code

I am trying to make a simple Neopixel strip running on a ATtiny85. The strip is 64 pixels long. I have some basic patterns but looking for something a bit more eye catching. Can anyone help write some code for me? Willing to pay obviously.

Topic by johnyhart  

PD Control of Ball and Plate System (Stewart Platform) via Python and Arduino

Hi community,I'm prototyping a 6-DOF Stewart Platform, i.e. a parallel mechanism also known as hexapod, with an embedded resistive touchscreen on its top plate that captures the current position of a ball moving on it. Coordinates are stored by Arduino Due and sent via serial to a Python script which elaborates data, computes inverse kinematics and outputs the 6 servo angles (again via serial port) to Arduino that, finally, moves the arms. As you can notice, velocity is obtained by a one-side differentiator and here it comes my first question: how much should be the sampling step? It takes 124 microseconds for Arduino to execute both the "AnalogRead" functions, but coordinates are stored in Python at a different clock (order of one millisecond). I picked sampling step h (see attachment 2) equal to the computational time of the Python script, with decent results, but still I'm not convinced.My second issue regards tuning of the PD controller: I first described the system with a double-integrator transfer function (from assumptions and simplifications over ball&plate; control) but the obtained controller parameters were far from the optimal ones. Therefore a simplified model of motor dynamics was added to the transfer function and new PD constants were implemented: simulation and real behaviors are far from being identical (high delay, not null steady-state error, higher rise time, etc.); however, inside small ranges of error and with reduced velocity, the ball reaches an equilibrium basin. The third attachment depicts the final transfer function where:- K is K_m*K_ball*g (K_m:motor gain constant, K_ball: ball inertia, g: gravitational force)- T is tau_m: motor time constant;I set K_m and tau_m equals to torque (Kg*m) and velocity (rad/s) respectively, according to servomotors datasheet: is this the right choice?Thanks to everyone for even reading and for any upcoming help.

Topic by MatRob    |  last reply

Wearing shed antlers? Answered

So when I was a kid I found this nice rack of white tail deer antlers, 8 points. Moved out of my mom's house and forgot about it, but recently they resurfaced. I'm thinking it would be really cool to wear them for Halloween.. I've done a lot of battle with search engines for the past few days but it doesn't seem like anyone uses shed antlers for anything terribly interesting. Much light-fixture-ing and car key racks abound. And the guy who made a USB key casing. Does anyone have any ideas on how to wear them such that they look about as natural as a human suddenly having horns could be? I'm not bald, so that's not an issue, but I don't have access to a lot of tools since I'm still getting started.

Question by PikeMinnow    |  last reply

How to Modify an existing circuit board?

Using a separate on/off switch wired directly instead of that supplied with this amazon product EL Wire, ESCOLITE EL Wire Kit Neon Lights Battery . How can I alter the circuit board to always go directly to fast strobe only? See the circuit board in this pic/video.As you can see in the last pic, I have removed the on off switch which was set up so each time you activate it toggles between / on, slow strobe , fast strobe, & off. The switch seemed to be just an on off mechanism, am I wrong?Amazon product is;=1

Question by MerrillL    |  last reply

Contact people who have made or commented on my instructable

Hi, does Instructables have the functionality for me to contact people who have made my Instructable? I'd like to let them know I'm planning some major enhancements and to find out if anyone would like to get involved.Best regards,Matt

Question by mattwood0    |  last reply

AC to DC adapter/charger output giving little sock Answered

My new AC to DC adapter/charger output giving little sock. And, when I use a AC tester on it, tester light up (like Ac line). This adapter use "Ferrite core transformer". Also, checked a "Iron core tranformer" Adapter, Also, some of branded mobile charger lighten up the AC tester slightly, but not giving shock... Is there any option to fix this problem...? Output is a 12.75V/1.2A. (Loads are working Perfectly) But, the body current is the problem. There are no any short-circuit. Giving some pix... (If you need full circuit diagram, Please inform, that may takes some time).

Question by arnablue    |  last reply

Should I use the front or back brake for my bmx bike? Answered

I have a bike thats been laying in someone's backyard for a few years and I'm trying to refurbish it and make it nice with a new paint job and some new parts. I'm going to take one of the brakes out. Should it be the front or the back brake? If I take out the back brake there will be a slight problem. You see something is wrong with it and the handle is stuck. I can't even squeeze the brake handle. A little help please!!! 

Question by General Eggs    |  last reply

MyDAQ breadboard help

I’m taking circuit lab and was told to get a MyDAQ and a bread board so I got a Normal breadboard. I was wondering if any one would be able to help me make my bread board look like the one everyone else got for there MyDAQ (the ones they got r easier to

Question by KevinAzcuy    |  last reply

Need a single use 120vac power outlet

Ttrouble shooting HVAC issue. Looking for a device that plugs into 120vac outlet. On until micro/millisecond power outage and if power goes off, will not accept power again until reset. Sort of a GFCI that trips NOT on a short, but on a power loss.Issue is that it seems HVAC gets quick power glitch and the condenser/compressor goes off (then on), and the evaporator/blower (with thermostat transformer) does not go off. We think this is what might be happening and need to prove it. Compressor goes into short cycle because thermostat is always "hot".Ohhh, forgot to say why - to prove that the issue is that the evaborator/blower does not go off with the power glitch, but the compressor does.

Question by wimmmy    |  last reply

1. How to properly read resistor? 2. How does resistor power (ohms) affect the circuit?

First question:How do you read resistor color bands? I'm messing around with 5 band resistors in my circuit, and I realized I didn't have any 330 ohm resistors... I was surprised because the kit said they were 330 ohms. Little did I know that a lot of resistors have a different value if read backwards, for example, red, red, black, brown, brown could be 2.2k Ohms or 11k Ohms, depending on which way you read it. How do you know their orientation? Second question: How do resistors affect the circuit? Vague question, I know, but I'm utterly confused right now. My blue LED is supposed to have a current of 20mA, which with a 9V battery demands a 275 Ohm resistor... But the circuit works with a 10K Ohm resistor or a 100 Ohm resistor... I thought smaller resistors were less restricting and larger resistors were more restricting. But if the higher Ohm resistor is more restricting, should a wildy high Ohm resistor prevent the circuit from working? Because the LED doesn't fade in luminosity until I get to a 100K Ohm resistor, which makes me question what a resistor does if the circuit works with a 100 Ohm resistor or a 100K Ohm resistor?

Topic by MarcusJubin    |  last reply

Stacked wood beam pyramid frame

Can someone point me in the right direction? i need to find either a tutorial, or the math i need to use for my cuts to make what is in the photo. i have been searching a solid 6 hours, through hundreds of "results" pages. have not found ONE link, not even an image of anything that resembles it. i am 98% sure that the problem is me not being able to word it properly. Please help. Thanks

Question by headlamp.mafia    |  last reply


My PC's splash screen shows the shop name from where I bought my PC. How can i Remove this? I attached screenshot to make it easy to understand my question. Please Help…

Topic by Shezi007    |  last reply

Epoxy vs resorcinol or other adhesives for boat building

I've been a big fan of epoxy for a long time. It's been recommended to me as the best glue ever, and lately as a great/durable coating to be used like paint. It's so popular that companies are starting to market things as epoxies that might be related but, really are something else. FYI anything sold as a "one part epoxy" is not an epoxy at all. it's something else. Epoxies must be 2 part.My father started building wooden model sailboat, and wanted to use Resorcinol. What?? Never heard of it. can't be good. must be toxic. use epoxy, Dad. Lately, I've heard differently, with some caveats.This was mentioned on forums: upshot is that epoxy bond strength weakens dramatically with exposure to heat or (maybe?) saltwater or UV light. Additionally, epoxy's bond is not as fatigue resistant as wood. So using it as a structural bond is questionable. Using it in hot (120F+) environments is questionable. Using it in saltwater environments is questionable.Since boats sit in the sun, tend to flex, and are often exposed to saltwater, how can we possibly use epoxies in long term situations.I had to search hard to find any info on Resorcinol, but it's cheaper, supposedly lasts longer. But, as far as I can tell, it's really hard to find. Comments?

Topic by danlocks    |  last reply

Changing DC Circuit to Pulsed DC

I am interested in changing my fixed current DC circuit to pulsed to increase the brightness of my LEDs. I really have no direction when it comes to making this pulsed circuit. I have looked into precision full wave rectifiers that I think are what I would be looking for. I am not sure what type of pulse width I would want. The one that I think would be ideal would be a Mouser DF01M, I am not sure if a pulse width of 200 microseconds is fast enough.

Topic by MarcusJubin    |  last reply

Building an ultrasonic soldering station ?

I have some strage projects coming up that will require me to solder things together that usually don't really like this.In my past job this was quite easy as we had an ultrasonic soldering bath and several ultrasonic soldering stations.Well, the access to those is gone :(At first I thought "How hard can it be to build one?"Not really too hard for a half decent soldering bath but a lot harder for a soldering iron...The soldering stations we used operated in the range of 50-60kHz.Commonly available transducers and their drivers however you find for 28 and 40kHz.Finding small ones in the range of 10 to 20W is also not easy.I can deal with a soldering iron that ends up in the size of a 500W wood burning iron as long as the tip is replacable.But what are the frequencies really required to solder for example on ceramic, titanium or lab grade glass?Does anyone have experience with doing this on lower frequencies than what the professional stations use?Last but not least:Is there any software available (preferably free or as an online tool) to simulate the quite long feed horn that is required with a soldering tip?Going with 1/4 wavelenghts is logical but how could I get the info on the actual shape required without simulating it first?I was thinking of using a heater cartridge like used for the hotend on a 3D printer to heat the tip.However, tests on my ultrasonic actuator showed the entire thing disintegrates within a few minutes, at least the filler and "glue" used to hold it all together.Would a free standing heating coil around the tip work?Heat transfer would be a pain and losses high, but should be possible?In case you wonder why: I just don't ave the thausands of dollars at hand required to buy one of these soldering stations....

Question by Downunder35m    |  last reply

Raspberry Pi (or similar) to control LED strip via commands etc?

I'm trying to achieve something which I would imagine isn't all that difficult. Basically, I would like something like a Raspberry Pi to connect to a set of LED strips.  Then via Bluetooth or WiFi I could send a command to turn them off or on from my phone. Thats it. I'd also like the same unit to power a little OLED or LCD screen that displays the time if possible. Does anyone know exactly what kit i'm going to need.  THere seems to be hundreds of different ways of doing this and I've got no idea where to start.

Topic by K20Evo    |  last reply

Charging Circuit

I was wondering if anyone had any ideas on how to make a circuit so that I could charge a battery, but that I can also power an amplifier when the battery is not charging. Currently I have a switch that switches between a charging circuit and powering the amplifier, but I was looking for a way to do this without having a switch that I have to control

Topic by Fozzibehr    |  last reply

Electronic Circuit- Help

Hello,My name is Daniela, I'm student and I need help to anyone who can help me :DProject goal: Control the temperature inside a closed chamberI need help to connect the all components and I don't know how because I'm new in this . I don't know how to amplify and to maintain the current, voltage so as to the whole circuit should work, what value is need for resistance, capacitors and other necessary components.I use a launchpad MSP-EXP430FR4133. I prefer to use power supply 3.3V (not 5V). To amplify the voltage I use a DC Boost Converter 2A power supply module MT3608 where the module output voltage can be adjusted.The temperature sensors it for hot side and cold side of Peltier element. A good size to have on the hot side is about 3 times as big a heatsink than on the cold side to don't find that both sides are getting hot. I have attached below a Block diagram, a List of Components, Description and What it looks like the final project. Please help me :D :) Datasheet: MSP-EXP430FR4133 : FAN-BM5115-04W-B50-L00 : : LM35DZ/NOPB : LMT86LP : TMP112AIDRLT : TEC-40-33-127 : MT3608 :

Topic by Daniela1111    |  last reply

Peltier Voltage control

I have a broken TEC wine cooler that I am converting into a temp controlled humidor. The MOSFET on the control board blew up so I was able to buy it for $9. I am adding humidity control and I want to log so I am going to control it with a raspberry pi. A Arduino would do but I want to program it in python and will have it host its own site to view data logging or to send failure alert.The wine cooler was rated at 70w, I'm not sure what the Peltier is rated but I am assuming less then that @ 12v. I did some tests with a bench PSU to see what it will draw at various voltages up to 8v (the max my psu goes):

Topic by TobinTelder    |  last reply