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Why don't old /community/* urls redirect to new /topics/* urls????

All of the older links to a topics on Instructables link to instructables.com/community/page urls, but a while ago (I'm not sure exactly when) all the /community/* pages were moved to /topics/*. Clicking the old /community links returns a 404 error, which is annoying because then I have to manually replace the "community" with "topics" in the url. So my question is, why can't all the /community/*/ pages redirect to their respective /topics/*/ pages?

Topic by scitronboy  


Electric knife sharpeners.....

Back in the day we already had these tiny grinding wheel like tools in the kitchen.Plug it in, press a button and slide the knife through.The blade was supposed to come out razor sharp if you trusted the ads....For obvious reasons a grinding wheel moving along the edge is not a good thing, especially not if both te up and the down movement work on the edge.As soon as they appeared they disappeared only to emerge years later in a "modern" form.The latest incarnation now comes with ceramic wheels to give an even sharper finnish LOLThe problem however is still the same, first the action of the whells then the fact that it is next to impossible to get different angles.They are really only good for some knifes you use in the shed if nothing else is available.A now much hyped electric sharpener is basically just a tiny belt sander with guides attached to it.And don't get me wrong, they come in handy for certain works.But if you ever used a belt sander on a flat piece of steel you realise that it is quite impossible to get a flat surface finnish.The belt curves around the edge and this results in a curved or beveled edge.Obviously the claim to sell these is that a beveled edge has superior strength and sharpness compared to a straight angled edge.And then there is the ability to adjust not just the sharpening angle but als the grid of the sandpaper.The finer you go, the better the result and sharpness...Now if we trust those who create swords from raw iron ore then something is wrong with the belt approch.These guys would tell you that you should always use a flat stone and to slice a piece of the stone.But also that a beveled edge is a sign of wear, something a good butcher will confirm.The angle of the edge party affects how sharp and durable the edge will be.Usually there is a compromise between blade thickness, meterial and edge angle.Just go from razor blade to an axe and include severel types of knifes between them.So a beveled edge in my opinion is only good for brute force tools but not that good for fine slicing and dicing.I tried to sharpen a wood chisel on one of the belt sander toys...It turned out to be far less precise and the edge was not fully straight.Could be down to lack of experience but if you ever try it let me know your results.The produced edge was also quite unusal and often bad when used as intendet.Far more chipping than cutting.Difference between straight angle and beveled angle when using a knife.You might want to do some lonely woodworks while fishing.A good knife now just eats into the wood and lets you cut and slice pieces of at almost any angle of the blade.With a beveled edge however you face the problem that your working angle is drastically reduced.Tilt the knife a bit too much and you suddenly just slide off the wood and into your flesh.If you grind and hone a knife to a 20° angle on a flat stone than from all angles above 20° you can cut.If you belt sand a knife to a 20° angle you end up with a bow over this angle.The actual usable working angle can be as low as 40° on a thicker blade.In theory it is possible to overcome this bevel problem.Sanders with a backing plate for example or by using just enough pressure to take material off.The first will destroy your belts quickly, the second takes forever.Some people just sand the knife at an angle to the belt, so instead of having the belt running at 90° to the edge it runs at 60 or 40°.Reduces the buckle but also the sharpness as the actual edge is now rounded.The only real way to sharpen a knife would be with a cutting or slicing motion, something that usually cuts your belts once the edge becomes sharp enough.So should you use them after all?As with all tools it comes down to quality and how you use the tool.If you know what you do and what the limitations are an electric sharpener can save you a lot of time.Someone with a desire for razor sharp knifes and tools might only use them on the lawn mower...You can however very well use sandpaper for sharpening a knife, which I will explain in another post....

Topic by Downunder35m  


how to make a hybrid go kart ( i.e., with the motor and the engine)..?

I want the go kart to start with  the motor and after it reaches 20-30 speed, it should run with the engine.. can anybody help..? How the transmission will take place..?

Question by sachin jain    |  last reply


From Anime to Reality

Someone was such a fan of Akira that they recreated Kaneda's bike from the manga and the movie. The bike is actually street legal and I'm looking forward to reports of it tearing it up in Neo Tokyo in vicious street gang battles. Extra bonus points if it manages to create light trails. Link

Topic by fungus amungus    |  last reply


(EMP generator)How can i make a long range EMP generator?

I have watched many video in youtube about, how to make EMP generator. But those EMP's range are really small, I want to make a EMP that can disable any electric device around me like, Disabling all the device in my room. So can Anyone help me with this??

Topic by harryt47    |  last reply


What would happen if you used a 24v battery pack in an 18v cordless drill? Will this damage the motor? Answered

Thinking about overclocking some of my 18v power tools.  I can adapt 24v battery packs to fit into them.  Obvious advantage is they will run faster and should run longer with the extra power.  My only concern is can this damage the motors?  I think the only real risk is overheating but it I take steps to avoid that would everything else be okay?  I've also considered hooking two battery packs together to run an 18v saw at 36 volts.

Question by etcmn    |  last reply


YouTubers who also post on Instructables

Who are your favorite YouTubers who post their project tutorials here on Instructables? For me the list isn't that long, looking to make it longer...Darbin OrvarEvan & KatelynPaul JackmanBrian LoughGlen (DIY Creators)Jen FoxbotJohnny Brooke (Crafted Workshop)Barb Makes Things

Topic by bekathwia    |  last reply


Microwave stopped heating and I fixed it.

Our microwave is about two years old and it stopped heating. The fan ran and the carousel went around, but food did not warm. I took it out of the upper cabinet mount and opened the case. I know about the big capacitor and discharged it with a screwdriver after disconnecting the power. For extra safety I clipped a jumper wire on both terminals. I watched numerous videos at YouTube on troubleshooting a microwave and on testing the various major components at home, but no component showed any signs of failure. Then it began to work again as suddenly as it had stopped working. About ten days later, it stopped heating again. After more testing, still no components showed signs of failure. But, I did squeeze the female spade crimp connectors a little with a pair of pliers before connecting them again so they fit more tightly when reconnected. The microwave has continued to work as it should. My wife remembers a time a few months ago when she ran it and ran it to get something to cook as she wanted it and the microwave stopped because it was overheated. I suspect a connection was weak and heated the metal in the connector enough that it became weak. Later it failed intermittently. We could have called warranty service, but we did not want to wait. Knowing what I know now, I doubt a serviceman would have patiently checked for weak connections, but would probably have simply replaced some parts. When those did not really solve the problem, the microwave would have been condemned and replaced. A replacement oven may not have matched our other appliances as well as our present microwave does. Test procedures for components in a microwave are different than they are for similar components used in (for example) a sound amplifier. This applies especially to the high voltsge diode. Do not connect a voltmeter to the high voltage side of the transformer. When running the microwave, be certain to have a dummy load in the cavity, like a cup of water. A very useful test that checks for power to the transormer primary is to disconnect the primary side transformer connectors and attach aligator clips from a voltmeter to the transformer leads. Then run the microwave for a few seconds and check for a full line voltage reading each time. A clamping ammeter to measure line current helps because the sound with the magnetron working is not too much differnt from the fan and carousel running without the magnetron working, but, it is easy to see the extra needle deflection when the magnetron is also drawing current.What seemed to be an expensive problem had an easy inexpensive solution.

Topic by Phil B    |  last reply


An idea for highly directional and loud loudspeakers

I am currently playing around with vibration experiments.Mainly in the ultrasonic range though.But when messing around with some vibration speakers I found a not so well documented misuse for themEveryone wants a big TV these days but once you have it the sound often turns out to come from a tin can.Those with a good entertainment or at least stereo system won't mind hooking the to it.The rest usually opts for a sound bar or how I like to call them shredderbox.Sooner or later they just fail to produce the sound you had on the first day - or they cost a small fortune.What is the secret to a powerful speaker?Firstly efficiency.Secondly the design.You need the right material to produce a more or less even reaction at all intendet frequencies.The design makes sure those frequencies that need extra attention get more volume output, like by using a little pipe for the low frequencies.Some even include a dedicate speaker for these low volumes.What if you could just build you own soundbar on a budget?If you have a failing soundbar with the actual speakers as the problem you could salvage the electronics.In case you can make do with headphone input or RCA connections than any cheap amplifier will do.Leaves the speakers...Vibration speakers are still underestimated for their uses...I tried the the usual approach of using a glue on vibro speaker:Place it on surface tha gives a re more or less decent sound.The thing is though that there is no ideal surface for them.A table can sound like the highs are missing, a hardwood desk might not produce any low frequencies while a window or plaster board wall bring the problem of wiring and vibrations.To check the reactions of sound on different media I, one day, mounted one speaker under a big tin can.Right in the center.The fun hit me when my tests with water were over and tried to play a song with the empty can.Of course there was some degree of tin can sound but the directional qualities together with the wide frequency spectrum made me experiment.The key is to find the right material and shape!You want something that is hard enough to vibrate properly but soft enough to allow for lower frequencies.I tried pipes, boxes, old plastic containers....But nothing seemed to provide a broad and even sound spectrum without distortions.If you vibrate a surface then only at certain, resonant frequencies destinct patterns will form if some dust or similar is place on the surface.In all other cases there is only chaos.Preventing the harmonics to form prevents harmonic vibrations to build up to distortion levels.Like it or not but waste seems to work just fine as a speaker ;)I made a plug to fit reall tight into a 2 liter juice bottle neck.The original plastic cap is just too soft.A vibro speaker glued onto the plug and the bottom of the bottle cut out and the soun was quite impressive.Proper use is however limited as the speaker would need to be mounted upright.Next thought was to utilise the bottom of the bottle too.By cutting a round hole in the side of the bottle I got an even more directional speaker with a better response to low frequencies.Placement of said hole of course affect how certain frequencies travel and where nodes can form.The size might also matter as the hoe itself, or better the material around it can get resonant at certain frequencies.You can cheat at bit though by using sticky tape, duct tape and so on as dampening meterial in badly affected areas.Especially with a wall mount for the speaker and the bottle hanging down behind the TV the effect is good compared to a standard shredderbox. The above design is certainly not for everyone although I think it has a wow factor to it if you show a decent sound coming out of a juice bottle ;)My next step was trying to find out how more fancy designs could work.So just stop reading here unless you like the idea of creating speakers that should not even work.Back in the old days we had more than just the speakers with magnets and cones.Anything that can vibrate can produce sound.It all depends on how much of it we can actually hear.My first exotic idea to really misuse a vibro speaker is a vibrating harp.Does not need to be in the classic shape though.A string in a resonance box, like a harp, guitar, violine and so on will start to vibrate at the set note.This is true even if the force for the vibration is external.You might remember the old school experiment with the two pitch forks on their boxes?Hit one and the other starts to swing too.If you make a resonance box for a vibro speaker with internal or external wire strings at different tensions or lengths you can amplify the sound for the notes that correspond to the strings.Make a relatively large box with some sturdy wires for the frequencies between 60 and 100Hz and you have a really powerful subwoofer from just 20W of input power...I think you get the idea on how to use amplifying strings now ;)My second and total misuse is the xmas tree.If you are a sparky by old trades then you might remember the mechanical frequency meters for generators or other things that required a stable supply.Well, if not than you should know the little wind up toys that play a melody with a drum and tiny forks.Imagine you would replace the glue plate with a rod.Depending on material and length harmonic nodes will form at various places and frequencies.Between those nodes the swing is maximised while the node itself appear to be stationary and without and vibrations at all.For example a steel rod of 1.2m would have a single standing wave at about 1kHz while a copper rod of the same lenght will be much lower in the frequency for a single standing wave.The xmas tree assumes that the rod is of such material that no single standing wave can form below 200Hz and that it won't swing too much at other resonant frequencies.Since aluminium is easy to work with and available in flat and thin bars already it would be my first choice for the branches of the tree.The required length is calculate based on the speed of sound in aluminium - you find online calculators for that.You want the lenght so that you end up with an even fraction of the wavelength you want to "play" with that strip.This allows for the rod to be placed right in the center of the strip where the standing wave movement is zero in the node.Make a lot of thin strips to get a broad frequency response.Placement on the rod can now be crucial.The best option I found so far is using a threaded rod and tapping the holes in the strips.The strips swing quite violently if long and at certain frequencies.And those not in resonance will still transfer their momentum to other strips.This can cause unwanted harmonics.Most evident when a single strips swigns violently at a certain frequencies.Adjusting the angle by turning it is often enough to get out of the overlapping harmonics.With enough strips it then really looks like a tree with flat branches.The sound might not be as loud and impressive as a plastic bottle as the virations are going up and down.But if placed in the right spot it not just looks nice but also makes people wonder where the sound is coming from.Last but not least my yet to be tested hidden speaker system - due to renting restrictions :(If you own a house of the standard frame design then you have plasterboard walls and ceilings.With a large enough surface of the right material, one or two vibro speakers can cover a really wide frequency range at good volume levels.So far I could only do tests in an old wooden window frame but the priciple works the same way between the wooden frames of a wall or ceiling.In my experiments a standard plasterboard sheet needs to be 100 x 100cm to get a more or less decent response for the lower frequencies.Before you rip your walls down use a stud finder and place your vibro speaker on the plasterboard between two studs or beams.I found that two speakers for the lower frequencies and three or four for the higher ones make a good sound.That is per channel and if you have the right size plasterboard sheet in the right place.No point if your left side is further away from the TV than your right.Ideally you replace the entire sheet with the speaker in the right spot on the new sheet but on the back.For obvious reasons this is far from being a perfect solution.But if you plan a full renovation anyway...A way out for older houses is the wooden floorboards.They make excellent resonators for low frequencies.The directional speakers could then still be hidden in picture frames of the right thickness and design.Anyways, I hope I gave you some ideas here ;)

Topic by Downunder35m  


Removing adhesive from vinyl tiles

I am having solid hardwood flooring installed in my first floor of my home. The existing flooring is currently 12x12" vinyl tiles. I am in the process of removing the tiles (using an iron). How do I remove the old adhesive that was used to put the tiles down? Is it necessary to remove even though felt underlayment will be placed under the hardwood? Thanks in advance.

Topic by meemee_0822    |  last reply


is there a way to melt rubber and steel together?

I've been thinking about this for a long time. What I am wanting to accomplish is finding a way to combine steel and rubber together to form a new substance where the two are no longer able to be distinguished from each other.

Question by Jakcavar    |  last reply


hi all, i need the right advice and guidance ...

I want to build a pressure washer engine from the train engine but it is uncertain whether the pump is in accordance with the engine .. engine gasoline / 1298cc / 75bhp / 6000rpm / 108 torque ..

Question by HafizK4  


Halloween Making: Why do we do this to ourselves!? ; )

Closing in on midnight on October 30th, and I found myself in a familiar situation . . .Making last-minute Halloween costumes and props for my kids!Here's a photo of my late-night kitchen table, where I was working on a homemade hover board prop from the "Back to the Future" movies. I paused for a moment to survey the scene and snap a photo, and couldn't help taking note of the silliness of the whole thing. It's midnight. I'm tired. My kids are asleep. And I'm up making this thing. WHY?Why do we do this to ourselves?! - - - - - -I know why I do it, but tell me why you do!Were you up late making stuff for yourself or for your kids? Share your reasoning and thoughts on being a creative Halloweener in the comments below. Be sure to include a photo or two of what you were making!

Topic by seamster    |  last reply


3d delta printer issues

Hi everyone. I need some help regarding the homing of a 3d delta printer, and it's my first attempt to create a 3d printer by scrap. My problem is regarding the homing, when I do the homing 2 out of 3 endstop work properly but 1(always one) doesn't work properly(see video). While the support is hitting the endstop, it moves a little back like the others, but then move up again and doesn't stop 'til I do it manually. there is someone that have some idea to solve the issue? Hope everything is clear enough, otherwise ask me :) Thank you in advance.

Topic by SebastianS217  


Motorized rollerskates, how do i calculate which dc motor to use? Some better than others?

I'm going to try and fulfill one of my childhood dreams; making a pair of electrically powered rollerskates.However i'll need your help if i am to succeed!I have decent knowledge of soldering and the electronic circuit wont really be a problem - i'll wire everything to an arduino duemilanoveSo here's my questions:1. I'll need a motor, is there a specific motor type that is best suited for the purpose?numbers:max loadage: 80kgspeed range: 0-20km/h (~12mph)Something like this, but in rollerskate format: http://www.skateelectric.com/index.php?option=com_content&task;=view&id;=38&Itemid;=45If anyone could point me in the right direction in regards to motor type and motor calculation i'd be really really grateful.I know that voltage is equal to velocity and amperage is equal to torque - and that torque is used as force to drive the wheels under pressure/friction.I've done quite a lot of research already, but i always hit a dead end, nothing here on instructables seem to cover the topic regarding dc engines - and no, i'm not insane enough to power a pair of rollerskates with an angle grinder - i want to have fun, not carve up the pavement and break bones (or spontaniously combust)ps:or this http://www.youtube.com/watch?v=HQzzjBR9EtwI'll do an instructable on this if i get it working, all i need is help with the motor, i'll do the speed regulating myself and all that jazz.

Question by Eirinn    |  last reply


Converting Fake cupboard doors

I just got a free display cabinet with 4 glass doors, but on closer inspection i discovered that the 2 end doors are fake. i want to know if i can cut them out, add hinges and hang them like functional doors.

Question by smikette  


What's the best brand/type of laser cutter for educational purposes?

I've been asked to source some equipment for my new department and I'm looking for a reliable product thats not overly expensive. It would be mainly be used by visual art students and design students. Ideally we would use it to cut board, cardboard, acrylic etc. I can see there are many exciting and interesting objects and artifacts which can be made (as demonstrated in so many instructables!) with this tool. I would be grateful for any advice available. Thanks in anticipation, Lawrence

Question by LAMcGrath    |  last reply


Knex Mp7 PDW

This is my new H&K; MP7 PDW. It features a removable magazine, a foldable front foregrip, iron sights, and it is very sturdy. Hope you liked it and see you next time with another knex gun!

Topic by TheKnexPro    |  last reply


why are the resistors heating up?

So i have 48 UV LEDS and each has a 470 ohm resistor on the anode so in a sense all leds are connected in parallel but it has a resistor on it. when i connect my 12 volt battery with 6500 MA the resistors begin to heat up. is there anyway to prevent them from heating up? or what is it that im doing wrong. ill provide a picture on the way the leds and resistors are connected if you want me to but hopefully what i said gives you an idea on how they are connected.

Question by diabloboy    |  last reply


Magnets in the Microwave, can you do it?

So does anyone know if you can put a magnet in the microwave? Will it cause some nuclear explosion, or rocket me back into time? Or will it just stay on my mug and witness the warming of my beverage?

Topic by Punkergal    |  last reply


Any idea on how to bypass Iboss Webfilter on Mac OS? Challenge!

My computer teacher gave us a challenge: our school used to have filters on most of it's computers, but they were taken down and replaced with something else. As a challenge, our computer teacher re-installed it on some computers and told us to try to get through it. I have had little success, my most promising moment being with a glitch in Firefox, that soon fixed itself and ruined my only gateway. To win the challenge, You have to get onto Facebook, myspace, and twitter, all of which are on the blacklist. Once there, you must post into a specific profile. You must do this three separate times, to illustrate that it can be done more than once. I know it is possible, because two other kids in the class have managed it, but I simply have no idea. The program is Iboss Webfilter by Phantom Technologies, and all of our computers are pretty new Macs. We have access on our computers to Firefox, Safari, Seamonkey, Camino, and Omniweb browsers. All proxy websites are blocked by the webfilter program. All firefox abilities are enabled though. Any and all suggestions or help is appreciated, If we pass the challenge, we get an automatic 100% in the class, because we have probably the coolest computer teacher ever. If anyone can give me a good solution that works, they get a patch!

Topic by ilpug    |  last reply


Knex HK 417

This is my Knex HK 417. It is very nice looking with its flashy side rails and stock. It was a very large gun that held a lot of ammo and shot very well. It was able to shoot passed the length of my house. It also had a removable magazine. I liked building it because it was different than your normal M4 styles.

Topic by Blue Mullet    |  last reply


what is the equation i should use to dilute 50% hydrogen peroxide into lower concentrations? Answered

Hello, i just got some 50% hydrogen peroxide, from my local pharmacy because they were out of 35%, plus for some reason 50% is free. anyways, i want to know whats the equation for finding out how many ml's of water i need to use to dilute a solution toa certain amount, as i want to use the 50% peroxide to make 30% , 22% and 3% peroxide. now ive looked on google and i couldnt find a thing , and if i did by chance come across it, i didnt understand it. what i want to know is how much distilled water will it take to convert 100ml of 50% hydrogen peroxide to the above concentrations, or if possible, could someone please give me the equation for converting any concentraion to any, please! also, whoever answers my question and solved my problem entirely will get a best answr i promise!!!

Question by oldmanbeefjerky    |  last reply


How can I learn the program for a cd drive stepper based arduino plotter?

How can I learn the program for a cd drive stepper based arduino plotter?Help needed.

Question by SHAMSUDHEEN MARAKKAR  


How to wire red led to my toy

Please show me how to wire a red 5mm led to this set up? I want the led to be controlled by on/off switch like the other leds. Please look at the diagram below as to how I have it set up n powered. Please note I was planning on using a 300 ohm resistor for the red led

Question by GNOEL82  


Need help to convert RadioFlyer car.

Hello, I want to convert RadioFlyer Tesla child car to variable acceleration instead of push - full speed. but have no idea how to do this. I have straight hands. If anyone is interested in this project it will be nice to collaborate. Thanks, Eduard

Question by EduardZ  


What kind of rope is best for a ballista? Answered

Would Nylon or Polypropene make a good torsion spring?Or would some kind of metal wire work better? By "better" i mean is able to produce the most force or is able to pack the most force into a 5/8"hole (thats the biggest drill bit i have).

Question by meburnfire    |  last reply


Is a DIY easy(wish) automated dispenser on a timer possible?

Hi all! My 11yo son is determined to make an automated medicine dispenser that releases medication at set times as his science project for school. (Inspired by 2 of his grandparents who are doing it tough with cancer). His idea is to basically automate the pill dispense so that the carer can load up each dose, and it will be released at the predetermined time, hopefully with an alarm or similar, to notify the patient... It's a intermediate school science project so doesn't need to be commercially ready, but he's struggling to work out how to automate it and attach the timer/clock function. Any ideas? I'm decidedly more mechanically minded than his dad, but that's not saying much, and whilst our son is definitely mechanically minded, up to this point he hasn't really had any circuitry etc or motors to work with, beyond lego technics etc. Is anyone able to point me in the direction of what might do the trick, without breaking the bank? Thanks so much!!

Question by ColeyC66    |  last reply


ISOLATION TRANSFORMER 120 to 120v

Often a GFCI is too sensitive outdoors. But I've heard that an isolation transformer might save you from electrocution. How safe would an isolation transformer be for running a fan, angle grinder, blower, space heater, etc outdoors? Where can I get one that will handle the amps I need?

Question by Toga_Dan  


Flip Flop 4 input 4 output

How to make a flip flop/toggle with 4 input and 4 output when one On, rest will be off automatic

Question by jasveerg  


Pin or pin header

Hi,I'm no native speaker. I was wondering, what exactly is the difference between >>pin<< and >>pin header<<.Is a >>pin<< just a male pin header, so, an abbreviation for pin header?tiadoris

Question by dorisbehrendt  


Transmit & receive 4ch audio

I am looking for a cheap solution to transmit and receive 4 channels of audio.Transmitter may be bulky, but the receiver must be small. (it is for an interactive installation)Audio The 4 channels will be converted to 2 channels stereo, so in total 2 stereo signals of audio need to be transmitted and received (within ~10 meters). Note that achieving the best audio quality is not of top priority.Technique Should I be looking at FM / AM of Bluetooth methods? I've looked at: https://www.adafruit.com/product/1958, but it would be nice if there is also a paired receiver board.It would be nice if the proposed solution is scalable to 6 channels (3 channels stereo).

Question by LudoP4  


How do I go about hacking a wheelchair joystick? Answered

I have a wheelchair and would like to use it as a base to a autonomous robot. I wonder if it would be better to hack the joystick or strip everthing away leaving the motors and frame and control it with Arduino or something similar. I have only used Arduino with small hobby motors. Looking for any suggestions.

Question by Paul Fjare    |  last reply


Help/suggestions/advice for loft bed at a height of 2.50 m !

Hello everybody, my name is Susanne. I recently moved into a very small but very high apartment in Barcelona. The ceilings in the entire apartment still have the original beams and are approx. 4.50-4.75 m. I am looking for suggestions/advice/help on how high to build. I have been doing a lot of research online already and have been unable to find any loft bed at a height of more than 2.00 m but would love to hear from anybody who has ever had a similar project or can think of a good way to work with height as oppose to space. In addition, I cannot seem to be able to find pictures let alone plans of platforms large enough for a king mattress and then some. I am really looking forward to any suggestions you might have!!!!All the best from beautiful Barcelona, Susanne

Question by SusanneBCN  


Adding more voltage to transmitter and changing the antenna size?

Hello! so I'm in a bit of a predicament right now, I have decided to do a project which checks the difference between antenna sizes and more voltage going through the transmitter to see if I am able to increase the range in a rc car. As of right now, I am thinking to use a 9v and a 12-volt battery but I am having trouble finding a RC car with these specifications. furthermore, I am looking for antenna sizes with 20cm and 10cm made of copper. I was wondering if you had any ideas on a cheap car just for like 5-6 uses that can also hold up to 9v and 12v with the antenna size being 20cm. Furthermore, I was wondering if i added more voltage to the transmitter, would that make the rc car range larger?

Question by phullamish  


How do I hook up a module camera directly to a screen.

I am trying to make a gadget that has a modular camera (something like this: https://www.raspberrypi.org/products/camera-module-v2/) directly to a modular screen (something like this: https://m.gearbest.com/development-boards/pp_29447.html?wid=1433363&currency=GBP&vip=16761629&gclid=Cj0KCQjwguDeBRDCARIsAGxuU8ZlNCKSrvsRVy_-1mbUWrXKJtY5oymxo1ve1GpYAXSQ2z4wJ3KUiZIaAq1nEALw_wcB) but I don’t want anything else on the screen. Is it possible directly or do I need a raspberry pi? If so how do I hook up the camera to the pi without the raspberry pi gui/clutter.

Question by EarthM    |  last reply


How do I change the main title, category, or keywords?

I cannot find my project searching with the keywords I have given. I would like to change/add some keywords and maybe change the category and the main project name. I cannot find anyplace that allows me to do this.

Question by KenS12    |  last reply


How can I get my instructable featured?

Hi I published an instructable a few days ago and i'd love to get it featured, what do I need to improve in order for it to happen? https://www.instructables.com/id/Baby-Crib-Musical-Mobile/

Question by HadasW  


How does one sort questions by date of submission?

Hi all,It's been a while since I've been to instructables. I see that Questions are back, but they seem to be listed randomly. one will be "posted 9 years ago", followed immediately by one the was "posted 6 days ago" followed by one that was "posted 3 years ago" etc.I don't see any ability to sort by date, although I suspect I'm simply unfamiliar with the new layout.Any help would be appreciated.PS> If some iblesfolk sees this post, I'd like to thank you for implementing post editing. It was always an aggravation to me that I'd have to delete a post in order to correct a misspelled word or otherwise fix some grammatical or cognitive error. Thanks also for implementing the menu bar above posts. (B/I/U etc)dropping this into "websites<

Topic by seandogue    |  last reply


Can an LED Light bulb that is made to run on AC, still run on DC? Answered

I'm wondering if taking an LED Light bulb that is meant to go in the ceiling of a house (made to run on AC) and sticking it on a battery, will it still work? Will it be just as bright on a 12 or 24V battery as it would be in a 230v ceiling of a house? I would assume it has a rectifier and the DC current should just pass through and light the LED's am I correct?

Question by flyinfinn    |  last reply


What is this tool

Does anyone know what this tool is?

Topic by weflyfish2    |  last reply


Regulations on a ground effect vehicle (Australia)? Answered

A while ago, I came across the work of guy in New Zealand who had made a hovercraft that could also fly like a ground effect vehicle. (See it here) And it got me wondering..... What kind of regulations are placed on a vehicle like this? Say I (while in Australia) built a similar craft to his, only smaller, lighter, and a single seater. Well, firstly, I'd like to know if it's legal or not. I'm assuming it would be, but with certain conditions, so; What licensing (if any) would be needed for it/me? And what regulations must it/I follow? Here's what I've taken in so far, although I don't know for sure that it's accurate/true: It's legal, as long as it does not exceed a certain weight, number of occupants, noise level, etc  I'm allowed to fly it as long as it is not able to get over a certain height (a couple of metres) It's a wing in ground vehicle, so it falls under the same category as boats, so the same regulations apply. Does that mean I'm not allowed to use it over land....? It'd be helpful if you could just point me in the direction of answers somewhere else, even Thanks 

Question by .Unknown.    |  last reply


i want to extract the tin from some tinned copper wire. how do i go about doing this?

hello, i would like to know, what the best way would be to separate tin from tinned copper wire. i recently attempted to build a MOT welder and now am left with quite alot of wire, and i require the tin for tin oxide. im wondering, what would i need to do, after i dissolve all the wire in hydrochloric acid, to extract the tin? its my understanding that tin and copper chlorides decompose easily into their oxides, and i only need somewhat pure tin,  as the electrode connector for my MMO titanium mesh (the part which will stick out of the cell which i will connect the cables to), and i only need roughly 70-80% pure tin metal, which i will reduce using my furnace and some pure carbon, in order to get a metal. or would it be ok for me to just melt the metals as is and let them separate in the crucible, and have all the fiberglass and resin just burn off? otherwise, would heating their chlorides (i require a soluble form to filter away resin and fiberglass), yeild tin oxide and not copper oxide, or would weaker acids like carbonic acid be able to dissolve the tin? sorry for all the questions but i really need some tin and i dont wanna blow this one shot i got here! i already have a theory on how this will all work, i just require a second (somewhat) proffesional) opinion. also i am already taking full precautions to ensure i dont get chlorine poisoning, so dont bother with the warnings. thanks.

Question by oldmanbeefjerky    |  last reply


Stepper motor working with nrf51dk (problem with timer i think)

Hello everyone, I am trying to make a program that makes work a stepper motor 28BYJ-48, my stepper motor is well connected to the ULN2003 and the ULN2003 is well connected to my nrf51dk, here is a picture of my setup : https://coeleveld.com/arduino-stepper-uln2003a/I foloowed this tutorial and it worked with my Arduino, so I guess the problem is not coming from there.I am now making a program using the nrf51dk, I am using nrf51_sdk_10.0.0 and the ble_app_uart as an example, my project is to control the motor via Bluetooth.But for the moment I just would like to make the motor runing.so I follow the same principe of code as in the tutorial for making it work.I need a timer, so I also followed the "Application timer tutorial" from nordic :devzone.nordicsemi.com/.../application-timer-tutorialhere is my code that I Added to the ble_app_uart project ://At the top I define the differents gpios that I will have to use//and step_number that is a variable use to navigate threw the differents steps for the motor to work int step_number = 0; #define motorPin1 1 #define motorPin2 2 #define motorPin3 3 #define motorPin4 4 #define APP_TIMER_PRESCALER 15 /**< Value of the RTC1 PRESCALER register. */ #define APP_TIMER_OP_QUEUE_SIZE 5 /**< Size of timer operation queues. */ //I add 4 different timers, one for each pin APP_TIMER_DEF(timer_step1); APP_TIMER_DEF(timer_step2); APP_TIMER_DEF(timer_step3); APP_TIMER_DEF(timer_step4); . . . //the code already defined in the existing project//Timeout handler for the repeated timer //I need 4 timeout handler, one foreach motorPin static void timer_a_handler(void * p_context) { nrf_drv_gpiote_out_toggle(motorPin1); } static void timer_b_handler(void * p_context) { nrf_drv_gpiote_out_toggle(motorPin2); } static void timer_c_handler(void * p_context) { nrf_drv_gpiote_out_toggle(motorPin3); } static void timer_d_handler(void * p_context) { nrf_drv_gpiote_out_toggle(motorPin4); } //Then I create the timers // Create timers static void create_timers() { uint32_t err_code1; uint32_t err_code2; uint32_t err_code3; uint32_t err_code4; // Create timers err_code1 = app_timer_create(&timer;_step1, APP_TIMER_MODE_REPEATED, timer_a_handler); APP_ERROR_CHECK(err_code1); err_code2 = app_timer_create(&timer;_step2, APP_TIMER_MODE_REPEATED, timer_b_handler); APP_ERROR_CHECK(err_code2); err_code3 = app_timer_create(&timer;_step3, APP_TIMER_MODE_REPEATED, timer_c_handler); APP_ERROR_CHECK(err_code3); err_code4 = app_timer_create(&timer;_step4, APP_TIMER_MODE_REPEATED, timer_c_handler); APP_ERROR_CHECK(err_code4); } //And here is my main //with the loop to make work the motor the same way I did with the arduino, but adapting the code int main(void) { uint32_t err_code; uint32_t err_code1; uint32_t err_code2; uint32_t err_code3; uint32_t err_code4; bool erase_bonds; uint8_t start_string[] = START_STRING; // Initialize. APP_TIMER_INIT(APP_TIMER_PRESCALER, APP_TIMER_OP_QUEUE_SIZE, false); uart_init(); buttons_leds_init(&erase;_bonds); ble_stack_init(); gap_params_init(); services_init(); advertising_init(); conn_params_init(); printf("%s",start_string); err_code = ble_advertising_start(BLE_ADV_MODE_FAST); APP_ERROR_CHECK(err_code); create_timers(); nrf_gpio_pin_dir_set(motorPin1, NRF_GPIO_PIN_DIR_OUTPUT); nrf_gpio_pin_dir_set(motorPin2, NRF_GPIO_PIN_DIR_OUTPUT); nrf_gpio_pin_dir_set(motorPin3, NRF_GPIO_PIN_DIR_OUTPUT); nrf_gpio_pin_dir_set(motorPin4, NRF_GPIO_PIN_DIR_OUTPUT); // Enter main loop. for (;;) { uint8_t str1[1] = "1"; uint8_t str2[1] = "2"; uint8_t str3[1] = "3"; uint8_t str4[1] = "4"; switch(step_number){ case 0: err_code1 = app_timer_start(timer_step1, APP_TIMER_TICKS(200, APP_TIMER_PRESCALER), NULL); APP_ERROR_CHECK(err_code1); err_code2 = app_timer_stop(timer_step2); APP_ERROR_CHECK(err_code2); err_code3 = app_timer_stop(timer_step3); APP_ERROR_CHECK(err_code3); err_code4 = app_timer_stop(timer_step4); APP_ERROR_CHECK(err_code4); ble_nus_string_send(&m;_nus, str1, strlen((char*)str1)); break; case 1: err_code1 = app_timer_stop(timer_step1); APP_ERROR_CHECK(err_code1); err_code2 = app_timer_start(timer_step2, APP_TIMER_TICKS(200, APP_TIMER_PRESCALER), NULL); APP_ERROR_CHECK(err_code2); err_code3 = app_timer_stop(timer_step3); APP_ERROR_CHECK(err_code3); err_code4 = app_timer_stop(timer_step4); APP_ERROR_CHECK(err_code4); ble_nus_string_send(&m;_nus, str2, strlen((char*)str2)); break; case 2: err_code1 = app_timer_stop(timer_step1); APP_ERROR_CHECK(err_code1); err_code2 = app_timer_stop(timer_step2); APP_ERROR_CHECK(err_code2); err_code3 = app_timer_start(timer_step3, APP_TIMER_TICKS(200, APP_TIMER_PRESCALER), NULL); APP_ERROR_CHECK(err_code3); err_code4 = app_timer_stop(timer_step4); APP_ERROR_CHECK(err_code4); ble_nus_string_send(&m;_nus, str3, strlen((char*)str3)); break; case 3: err_code1 = app_timer_stop(timer_step1); APP_ERROR_CHECK(err_code1); err_code2 = app_timer_stop(timer_step2); APP_ERROR_CHECK(err_code2); err_code3 = app_timer_stop(timer_step3); APP_ERROR_CHECK(err_code3); err_code4 = app_timer_start(timer_step4, APP_TIMER_TICKS(200, APP_TIMER_PRESCALER), NULL); APP_ERROR_CHECK(err_code4); ble_nus_string_send(&m;_nus, str4, strlen((char*)str4)); break; } step_number++; if(step_number > 3){ step_number = 0; } power_manage(); } }Probably I am doing Something wrong with the timer, because when I modify it and decide to use it with a led for testing like in the tutorial, the motor makes noise but doesn't move and the led works. If someone can help, it's been hours I am on this problem and I can't find my mistakes.

Topic by BenjaminP106  


Maker/fab lab/AI special call for papers invitation

Hi !My name is Andre Peres and I'm a professor and fab lab manager at Brazil.Me and Fabiana Lorenzi are chairing a special track at flairs (The FLORIDA ARTIFICIAL INTELLIGENCE RESEARCH SOCIETY) about fab labs, makers and AI. about the track: http://www.invenio.com.br/flairs/about flairs: http://www.invenio.com.br/flairs/about We are inviting interesting projects to submit to this track. When we made this special track we wanted to give fab labs and makers the opportunity to get together in this academic environment to talk, exchange experiences and also to get this opportunity to link academic research, the maker movment and personal digital fabrication.We hope you consider submiting your project to this special track, and also to see you at FLAIRS. best regards;André.

Topic by decoP    |  last reply


Voltage for NiChrome?

Will 2.5 volts be enough to heat a small segment of NiChrome wire up to/over 100 C? If it helps, the power is coming from a 8.1 kJ 2.5v 2600 F super capacitor which can unload very quickly.

Question by LiquidLightning    |  last reply


Ideas and Methods for DIY Truck Topper

So in 5 months starting February I'll be getting my first vehicle. If I do get a truck, I'll be making my own topper out of wood. Now I have a reference picture but I want it out of wood just because it's more secure and looks pretty. Also because I will be making a door on the back that stands tall but can also be walked through. The first two photos is how I want to make the topper but I need methods and advice to do so. The third picture is how I want the door. I'll try to answer any question when you have them but keep in mind I don't currently own a truck, this is for 6 months down the road.

Topic by jlowery5    |  last reply


Symbols Configuration for PCB Libraries

Hi everyone !, I would like to know what kind of symbol configuration most of engineers or pcb designers use or what standards follow to create the symbols.I found some recommendations and i have two examples of symbol configurations , In the "Image #1" i created the symbol placing inputs and pasive pins on left side and outputs on the right side and in the "Image #2" i followed the symbol configuration of the typical application of the datasheet.Which of the two configurations is preferred or recommended to use and why?Thank you.

Question by Juan DavidD3    |  last reply


10 Watt LED Circuit

I am a software developer by trade and have little or no experience regarding LED and/or electronic designs. I am hoping someone here can help with a project I am working on using high brightness LEDs. I have studied several 'instructables' and specifically dan's "Circuits for using High Power LED's." My project consists of a few high brightness LEDs that will be placed in a high ceiling room with the brightness controlled by a microcontroller based on the light in the room (time of day, sun in window, etc). The microcontroller will use photocells to determine the brightness in the room and then adjust the LED using PWM pins. The LED is 10 watt and approximately 450 lumens. Attached is a circuit I drew as a starting point and would like help in determining if it will work, I am close or does it need to be trashed. I am not sure what the value for the resistor should be. Below are some calculations but not sure if I am on the right track or not. No need to be kind, I am more interested in getting it right and not losing any 'magic puffs of smoke' from any of the components. Here are the specs: LED IF: 1.6 A Peak Forward Current: 1.7 A Forward Voltage: 8 V LM350 (heavy duty version of LM317 IO_MAX: 4.5 A 1.2 - 25 V adjustable regulator BC337-40 Collection Current - Continuous: 800 mA dc Total Device Dissipation: 625 mW Resistor: 5W or 10W Voltage Amp Ohms Watt 8 1.60 5.0 12.8 8 0.80 10.0 10.0 8 1.10 7.5 8.5 Note: LED and components will have adequate heat sinks.

Topic by desnotes    |  last reply