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Dry Ice Air Freshener

Michael Natkin writes a culinary blog Herbivoracious which includes hundreds of recipes for a vegetarian diet. This, however, is an experiment using dry ice to create beautiful clouds of smoke while filling your home with sweet scents.

Topic by Carleyy    |  last reply

Really, really basic question about resisters Answered

I am building a battery pack out of pouch LiFePO4 pouches 180Ah, 12V charged from a solar charger at 50A. I have an Arduino with ethernet which I am using to monitor it and I'm assembling the circuit board. 2 current measuring boards (1 for charge, 1 for load) and 2 voltage splitters to drop the 12-15V down to the Arduino's 5V max analog in.It's these voltage splitters that I'm puzzled by. The recommendation is to use the lowest resistance to give the results you're looking for. So if I have 12V in, R1, R2, Gnd and R1 and R2 are low value resistors, what's the difference between this and a short? Do resisters limit the current, too?Just trying to figure it out before I start frying components.Mike.Edit: I was a little vague as to the setup. I am fitting out a van for full-time living. This has the LiFePO4 power pack which ranges from 12-15V and a 50A MPPT solar charger. Within the battery's housing, I have an Arduino which is tasked with monitoring what's going on with the power system and sending the status across the network via an Ethernet connection. It should make monitoring it a lot easier than digging it out, opening it up and connecting a multimeter to it! If the current gets too high (or the smoke detector kicks in or the temperature gets too high or something on the network tells it to) then the Arduino can isolate the battery.The current on both the load and the charge lines can be monitored with small current-voltage boards across the ground lines so no problem there. I would like to be able to monitor the voltage in both the battery and the charger so it's really down to converting the 12-15V of the power system down to the 0-5V for the analog pins. Lopping off 10V would be ideal but scaling it with a voltage divider/splitter seems to be how it's done.As you may have gathered, I've been more of a software person and I'm having to learn electronics by finding problems, using my 30-year-old high school physics to figure out what I don't know, looking it up and then either trying it or figuring out what I'm missing.

Question by ImmortalSoFar    |  last reply

3.5mm 2 output Audio switch with SHIELDING?

Hi, I'm interested in building a 1 input 2 output (3.5mm) A/B switch. At first I was looking to purchase one, but all the small units like I need have reports of noise being added to the signal because of poor or no shielding. I've found several instructables on building something I can use, but none mention shielding. Any suggestions or ideas on how to achieve this? (See attached pic)

Question by KaisoArt    |  last reply

What is this things use?

I researched about it and, it told me what it was, but what do I use it for? does it limit current?

Question by Cheesey125    |  last reply

Dc generator and power led

Hı I have a project. My teacher wanted me to produce energy by using a dc motor and light a power led with it and calculate the power that generated. I choose 12 volt 15600 rpm 1.2a dc motor. I assume i can spin the motor 15600 rpm. Now which power led i have to use and how am i going to calculate the power. The teacher said you can add resistance. Can you help me please.

Question by fatih.ygmr    |  last reply

Solution to putting tons of work into an instructable, and not having it featured

Hello! I have been working on a project for about 4 months now, mainly for myself, but I am also trying to get it featured. With all of the time I am spending on it, I keep thinking about what a bummer it would be to not have it featured. But I just recently thought: What if we could have our Instructables reviewed BEFORE we post them so that we can tell if we need to rework or improve our instructable to get it featured! I thought that I could share this idea with the community, and maybe we can find an even better solution.!

Topic by Cheesey125    |  last reply

Arduino IR sender

How to use the RAW Data I received from Arduino ir decoder, with the esp8266 ir server library to control a Time Warner DVR receiver? The Remote control I decoded is made by Philips company and the model number is RC122.

Question by naderjazz    |  last reply

How can I convince my dad to let me take apart our broken microwave?

There is beryllium or whatever inside of it and he isn't letting me take it apart. the beryllium is only in the magnetron and I won't touch it but he still isn't letting me.I was very stressed at the time of the writing of this, so please do not base my character upon this topic.

Question by Cheesey125    |  last reply

Neverending Seltzer Water Maker - Interest?

I've been making my own seltzer water for many years. And in normal situations (you know when there isn't a worldwide pandemic crisis.), I have to refill my 5 gallon keg about once every 7-10 days. But lately with a family of four at home, my refill cycle is down to 2 days!This has forced me to design a new system that will replenish itself automatically overnight. Basically, once its setup, the only thing it will need is a new tank of CO2 when the gas runs out. Even for me with a 25 lb tank at this high consumption rate will last about 4 months. So it will be a huge improvement for me, but was unsure if a broader audience would value the concept/project.Basically, I'm curious to know if people would be interested in an Instructable detailing this system. It will be completely electro-mechanical, and not require any raspberry/arduino/software/etc. (Also, it will be completely different from the other endless supply seltzer Instructables already published, and should be much cheaper too!)The system is currently in design phase, so I'll be much more diligent about documenting the process if others would be interested.Thanks in advance for your responses.(You can see my Instructable "Lazy Man's Carbonating Shaker (Seltzer Water or Beer)" to get an idea of my current setup.)

Topic by Icelandian    |  last reply

How do you correctly charge a 12V lead acid battery using a 5V phone charger and step-up converter?

I'm making a bluetooth capable, battery powered portable speaker - I have some 12V lead acid batteries lying round and I want to use those since the amp accepts 12V power. Its important to me that I can use a 5V micro-usb cable as a power supply because they're so common/universal. Everything in my setup works fine except for charging the battery. I've tried two different step up converters. One overheats massively when power in is connected to the 5V supply, and the other is a slightly fancier buck-boost converter which comes with a small LCD which displays voltage and current out - however this one, once connected to the battery, shows a tiny jump in current and then goes down to zero. I'm fairly certain the converters aren't inherently faulty since I've tried running the converter output straight to the amp rather than the battery and then everything seems to work fine.How am I meant to charge this battery? Is there some component I should be adding in somewhere?

Question by CameronCox111    |  last reply

How to Repair Air Purifier Damaged by Power Surge?

Does anyone know how to repair an air purifier that has been damaged by a power surge?  I have several Cleanaire D2000 units - which are absolutely outstanding, BUT which have a weakness of being particularly susceptible to power surges.  Since they cost $400 apiece, it makes for a pretty costly power surge.  Are these kind of things repairable, and if so, where would I (or my technically-gifted friend) start?   I'd like to see if it's possible to repair one of these before going out and buying a replacement.  (Then the next step is to buy a good surge protector!) Thanks!

Question by Thaas12    |  last reply

Hammock stand - How to Build an Outdoor Hammock Stand $25

HelloI would like to know the angle between the horizontal support on the ground and the lateral upright that supports the hammock fixing ring. And if possible the height in cm from the ground to the hammock fixing ring. Thank you

Question by granyan    |  last reply

Anyone have plans for building roll out chicken nesting boxes?

Nesting boxes are usually about one cubic foot.  Several hens will use the same box.  Some hens will pick at eggs and break them.   I am looking for box plans that include a slanted box floor combined with a collection box so after an egg is laid and the hen leaves, the egg will roll into a bin.

Question by mitch2989    |  last reply

I have an allergy to the silicone in my CPAP mask liner. I seek an alternative "skin safe" material to mold a new liner?

I am seeking a skin safe or hypoallergenic moldable & (pliable after molding) gel-like material (firmness medium) that I can use to mold a replacement for my silicone CPAP mask "liner." CPAP masks are worn nightly by people with the medical condition - Obstructive Sleep Apnea - the mask is connected by hose to a small medical machine that forces air down your throat to keep those with Sleep Apnea from ceasing to breath while sleeping.  The "liner" is the replaceable soft part of the CPAP mask that goes against your face (skin) to assure a good seal and no air leakage) I personally have the capability of making a mold of my original silicone mask liner then reproducing it (for my personal, not commercial purposes) - I just need to identify a moldable material (with similar characteristics to silicone), but that does not cause rashes and skin outbreaks and the allergic reaction to silicone. Hundreds of people have an allergic reaction to silicone. Multiple dermatologists have been unable to provide a solution or effective treatment. Any "skin safe" (might be hypoallergenic or not but probably would be?) moldable material that may be currently used in the production of various medical devices or medical devices that are inserted into the body (cosmetic surgery) or devices that are by necessity held against the skin would likely be a candidate for me to produce an alternative to a silicone mask liner. Or it might be a material with other uses or a totally new material on the market? I note that there are literally hundreds if not thousands of CPAP mask users who suffer from this very same allergic reaction to silicone but unfortunately, to date, the CPAP manufacturing industry has chosen to continues to produce 100% of CPAP mask liners from silicone alone. There is no alternative on the market. One can easily find hundreds of posts on CPAP forums complaining of this same silicone allergy problem with no solution currently available or even on the horizon. For legal reasons, I unequivocally state that this post should not be construed in any way as a "negative critique" of the CPAP manufacturing industry or any of their products or the materials used in those products, but it is simply a genuine request by an individual in need, for help and assistance from a very highly knowledgable base of Instructable readers. I further note that the various types of cloth covers that are sold by some small niche companies, to cover the silicone CPAP liners are (in my personal view) only partially effective for some, and fully ineffective for many (myself included) in addressing this silicone allergy problem. This (in my personal case) is NOT the needed solution It is a band-aid at best. The solution is a hypoallergenic moldable alternative to silicone that has the same pliable sealing properties as silicone but without the allergic skin reaction. Additionally,  I have an allergic reaction to the "neoprene" material that is used in the production of virtually 100% of CPAP mask harnesses (the strap that goes around and behind your head to hold the CPAP mask in place). So I am also seeking an alternative material that I can use to construct a (non-neoprene) harness. A slightly stretchable hypoallergenic material would be ideal but frankly it could be made of any (skin safe) material even if non-stretchable. I am open to any suggestions. If you wish to view an example (image) of a full CPAP mask you can see it here: If you wish to view an example (image) of a CPAP mask silicone liner (replaceable) you can see it here: If you wish to view an example (image) of a CPAP mask harness (made of neoprene) you can see it here: I am very grateful for your kind assistance with this rather challenging problem...despite considerable ongoing research on my part I have been unable to identify an appropriate alternative (to silicone) material for my CPAP mask liner nor have multiple individuals suffering with the same silicone allergy been able to identify an alternative. I have frequently trolled all of the major CPAP forums and there simply has been no effective solution identified to properly address this silicone allergy problem. 

Question by kick991    |  last reply

I am new!!!

Hello! I am a new member here and I really love it! I have to say that this is one of the best websites that I have seen.I just wanted to say that I also have a website. It is a new website. It is a language learning website, but I need people who are willing to contribute to teach a language. You have to be fluent in the language you want to teach and in English. It is okay if you are not fluent in English though. Please check the website out and apply for the Enthusiastic teacher.Also, the categories are not accurate. Here is the link to the website: If you have any questions, please email me at: learn.something80@gmail.comThank you!

Topic by catcrown38  

RSS Feed Please

This website could use an RSS feed.  I'm unlikely to visit often, I'll junk-mail an e-mail newsletter, but an RSS feed always catches my attention.

Topic by raywood    |  last reply

Star Spangled Banner On Keytar

It's me playing my Roland AX-Synth Keyboard. Watch and comment.

Topic by Oblivitus    |  last reply

LED Battleship game

Just had an idea for simple to play but complex to build battleship game. If i had the money and resources to build it myself i would. So i just thought i would share the idea and see if anyone else is interested in making it. Basically the target and ship fields will be made from a large pin board for LEDs to plug into. The Ship field of one player will be wired to the target field of the other player. So when an LED is plugged into the target field and there is an LED plugged into the same spot on the opposing player's ship field the target LED completes the circuit lighting both LEDs indicating a hit. No need to call out coordinates and can be a good game for the hearing impaired. The LEDs for the ship can be placed onto sets of header pins. It would take allot of LEDS to make but would be an interesting game. 234 total LEDs are needed 34 of which will be used to create the ships. each player get 100 LEDs for shots (less then 100 are actually needed to complete a game. peg board could be made from old IDE female headers. Board should be marked with line indicating negative side of the connections. Negative side of LEDs should be visibly marked to help the user determine the right way to plug them in.

Topic by mpilchfamily    |  last reply

How to build a super-thrust blower out of electric blowers to drive a paraglider ?

I want to build a paramotor which is electric and not propeller driven. Therefore, I want 'hand dryer' type blowing technology to provide sufficient thrust. Does anyone know if large super blowers are available in portable electric form ? Could this work ? How much thrust does the propeller create ?

Question by gregsmithsays    |  last reply

Schematics for a simplified "QI" charging/power supply circuit?

I have found schematics and code for a basic implementation of the QI standard using some Atmel processor.Also tons of circuits for "wirless charging" or "wireless power transfer".The ones with QI specs are way too much for m needs, the later leave some features to be desired.What I would like to be able to accomplish:Have a wireless power transmission working at a max of 10W and at a distance of 5-10cm.Most likely the power requirements will by in the 12V range with around 500mA on the receiver side.The features I would like to get without using a microprocessor:1. Basic and limited frequency tracking.As alignment is not always 100% the resulting differences for the near resonant frequency should be compensated by the circuit.2. The transmitting coil shall only be driven at the power levels required by the receiver.3. A bit like QI, the transmitter shall be able to detect that a receiver is present and fire up.No fancy safety features for foreign object detection required, no complicate hand shake with coded bits and bytes either.Pretty much simple bang-bang with some PID control on a wireless base.I am sure there must be a suitable circuit or even IC for thejob somewhere but I struggle to find something minimalistic enough.Oh, in case you wonder why I would like this to work:I am planning on building a rig for my camera to create some fancy night time videos.For this I would love to have the cam in an airtight housing with a sort of docking station - wireless.And for another project I need some wireless power transmission to make a levitating moon glow without batteries and cables ;)

Question by Downunder35m    |  last reply

Glue real flowers to a wooded crate

I have been working on a project and am having difficulties maybe someone can give me some pointers. I have made wood crates and I want to glue dried flowers on them. However have run into many issues. Drying flowers is a art and currently all my dried pressed (all have to be pressed to glue onto crate) flowers look horrible. I use silica gel beads or borax and cornmeal. Any points or sites that show best drying pressed method or maybe I won’t have to do that....the flowers need a coat on them for protection from the sun as well as bumping. What glue can I cover a flower with that preserves them and protects them. Can I use clear silicone? Then no drying needed? Thanks

Question by Autumn1333    |  last reply

Running a 6v toy r/c car on 9 volts? Answered

I have a toy r/c car that I've done some experiments on, and I was wondering if there was a way to upgrade it to 9 volts, and if that would make it faster? I've already tried using a single 9v battery, but that either messed something up, or killed the battery really fast. So I'm back to running it on 4 AA's, but I found a 6 AA holder, and I was wondering if using 6 AA's to get 9v works better than just a 9v battery.  Thanks!

Question by Zem    |  last reply

Recharging a `battery bank

Im looking for a dc motor that will carry a load of three 24v 100a alternators and a suggestion of what size and type of batteries will carry the dc motor. NOTE one of the three alternators purposes is to recharge the batteries powering the motor. Please help with a suggestion of what type of motor to get, the voltage or hp of the motor and what size battiers will be suitable to carry that motor.Thank you

Question by promisedominicakpan    |  last reply

Instructables format

I think I have a good instructable to share, but it is quite big, lots of photos, couple videos and lots of work (thousands of solder joints, hundreds of wires). I realize there is a format to Instructables but not sure how to use the format with my own techniques. Eg, I use MS Word a lot, also Excel and Visio. I could make a complete "instructable" with Word and these programs but it wouldn't follow the format.I started an Instructable topic just to see how I can abide by the Instructables format. The first requirement is to upload photos. Does this mean the photos are all put in an album that I can choose later on when I write the text? How do I handle links to my YouTube videos? I have my own website so I know a little bit about page composition.Am I on the right track? Is there a preview available before publishing in case I really screw it up?My plan is to show all the mistakes I made (ie the WRONG way to do things), followed by the RIGHT way.

Question by queenidog    |  last reply

Ws2815 and ws2812 in same systems issues

New to using these lights. I needed some side fire and circular leds which I have only found in ws2812 and also need to use the ws2815 to lower current draw on my motorcycle for parades. I have a 12v to 5 v converter and a wifi controller with presents. the ws 2815 work great, but when I connect the ws2812s to the data signal, everything goes crazy. They use a common ground, and a 12 volt and 5 volt source depending on lights, but a common data signal. Was wondering if the second date signal on the 2815 is the problem as I do not have it connected to anything or if there is a conflict between the two types of lights. Any ideas or help is appreciated.

Topic by wingrider58  

Raspberry Pi Zero Dedicated Console

I have written a small 15 Puzzle game in Java—the only programming language I am fully comfortable with. I’m satisfied with the game itself and would like it to have a simple platform on which to play it rather than it just being a .jar on my computer. I would like to make a small handheld with raspberry pi zero just to run the game on boot and let that be that. I plan to use a usb encoder to map the buttons, so I don’t have to worry about programming the gpios with Java (as I have found this to be a bit of a hassle). I would love any ideas or assistance regarding the best way to play the Java program on boot and maybe a way to effectively shut down the handheld without potentially corrupting my microsd. Any other neat ideas or tips for the project are also, of course, quite welcome. Thank you!

Topic by ToggleSwitch    |  last reply

Facebook login feature not working.

Hi there,While I tried to login using Facebook Auth on instructables, it shows up an error saying "App not setup". I think it's a bug somewhere cause I tried it from multiple other devices.

Topic by jugadu_in  

how do i make prosthetic finger tips so i can play my guitar again?

I chopped off the tip of my finger with a mower....ouch, now im two months in and i still cant play chords on my guitar. if i super glue leather to it i can play my bass. i have also used banjo picks with band aids wraped around them but these get in the way when i play chords. i cut off about half an inch from my ring finger and nipped my middle finger on my fret hand. any help would be great thanks. D.J. ps the pics are from a week out of surgery

Question by djloney    |  last reply

Wire Dual garage motion sensors to a backfed overhead light fixture

My garage has a 2 light switches wired to the main light fixture. Problem is I think the fixture is fed with 2 wire (no neutral) and both light switches wired from it. Circuit looks like this I believe. I don't even think I have a ground wire, its an older circuit and half my house has no ground.Is there a way I can wire in two motion switches instead? Most I've seen require the ground or can't operate properly with a circuit like this. My knowledge is weak on the subject and would appreciate any guidance!

Question by stephenjgarden    |  last reply

What is this tool? Answered

Can anyone tell me what this tool is?

Question by adriangenereux    |  last reply

which side are you on? PSP Go vs. 3000 vs. 2000 vs. 1000

Which psp version do you like better? PSPgo (the sliding PSP), 3000(slim & lite), 2000 (slim), or 1000(phat)? leave a comment saying what your dislikes and likes are of the psp you choose.

Topic by amakerguy    |  last reply

Raspberry Pi based security camera system

I understand the tech are there scalable kits that I can purchase right now

Question by Dragonfly 62  

​PSU go to self-protection after desoldering motherboard's wires

Computers' PSU are very convenient power source, which can be used in numerous application. Usually such applications don't need its wires connected to motherboard. Four times I observed issue, when different working PSU went to self-protection after desoldering bunch of motherboard wires. Even cutting wires, not desoldering them, produced similar issue. I mean PSU went to self protection, when after switching on it works during a few seconds and than it automatically switched off. What can be the reason of such issue and how it could be fixed?

Question by Vaster    |  last reply

Dutch / Nederlands

Hey, my native tongue is Dutch so if you need any translation into / from Dutch send me a message. Hallo, mijn moedertaal is Nederlands dus als je vertalingen nodig heb naar / van Engels stuur me een berichtje.

Topic by knutknackebröd    |  last reply

Use an LED monitor as a lamp - faking a VGA signal?

I have an LED monitor with a smashed screen that I'd like to repurpose as a light panel. The backlight still works (driven from the onboard controller) but cuts out after 20 seconds or so. I assume this is because the board fails to sense a connected source (it has VGA and HDMI inputs) cable and switches to standby. Is there a simple way of "fooling" the monitor that there's a source conencetd so that it remains lit?

Question by Henmarsh    |  last reply

Rate my drawing!

I would like some feedback on my work, please tell me what you think :) thank you!

Topic by FoxyPenguin94    |  last reply

Any Ideas what this might be???

I was out metal detecting on our property and found thisitem near a license plate from 1914! This item is heave cast metal, looks like it may eitherallow something to function or prevent it??? I have also found a Reach Plate for a Wagon dating inthe late 1800's.

Question by Farmfinds    |  last reply

Thickness of compress air tanks, and max pressure of brass fittings?

Who here knows about compress air? Regarding about the tanks in standard air compressors if i'm ryt (70 to 90psi) how thick is the tank and is it stainless? also, standard brass fittings? wat r der maximum presure?? i need to know these for safety before i can proceed with my proj, if im correct presure tanks have d tendency tio explode. and metals shatter. so... i dont want to die yet... can anyone help?

Topic by No-Shi-De    |  last reply

how do I make colored surf wax?

How do i color homemade surf wax and how do i make it smell different?

Question    |  last reply

Old Phone That Can Play Games? Ideas...

Hi guys, so I was recently talking with my friend Omar about random stuff, and (like always) our conversation somehow got really off track and we ventured into the history of old phones (Nokia 3310...breaking everything we touch since 2000). We somehow got to thinking about how old bar style phones could be useful for the making community. My thought (which I incidentally shouted out as loud as a human can go) was this: what if we could put a really basic game onto the phone? Would it be possible with the current hardware? Maybe...and the controls are there, most phones have a D-pad with 12 keys (which could be special function keys in the game). I was thinking of games along the line of Doom, or any old FPS game...but in retrospect, that would be ambitious, and to be practical, a stick man game would probably be the minimum.  So my questions are: a) would it be possible for the hardware on the phone to be wiped of all software and would it be good enough to support the code. b) is it even possible to reprogram the phone, or even get some sort of bootloader onto the device? Probably not. And if not, is there any other way to put a game or any file onto the phone's hardware... I guess that's it. In general, would it be possible, and if yes, could anybody give me a few starters so I could try to do it? Thanks, Ivan

Topic by IvanT3    |  last reply

Why can't my laptop find any wireless network?

I was using my laptop when suddenly the power went out. When it came back on, my laptop couldn't find my wifi, but my mobile connected to my wifi without any trouble. I even tried to connect the laptop to the mobile's hotspot, but no luck. It's not even able to connect or even show any of my neighbour's network. I've tried every kind of solution but it all has been in vain. Someone please help me. I'm using a sony vaio sve13315cnb.

Question by amr111sam    |  last reply

Need help making a fake hypodermic syringe

Hello. I'm set to film a scene where a needle is used to inject someone. I've found a lot of places that sell and rent fake hypodermic needles, but way over my budget. Is there anyone here who would/could be interested in making one for these? I attached a video of one being demonstrated. I'm just having a mental block on how to create one myself. There's definitely a spring mechanism, and the tip is dulled. Other than that, I'm lost.

Topic by blabowski    |  last reply

Resistors on the Bluetooth speaker!! Answered

I wanted to know why the resistors were used on the Bluetooth speaker and if I need them,  what size are they? 

Question by LASOUND    |  last reply

3D Printing Fails.

I'm not exactly sure why, but the BBC collected a bunch of 3D printing failures. I couldn't resist sharing the screenshots and captions, especially in light of Fungus' recent topic. Enjoy.

Topic by Kiteman    |  last reply

Time & space: A dimensional discussion

Would anyone care to discuss the forth dimension of space? I have included a little Paint drawing I made. The "box" drawn as we would see a 3-D glass blox. and a 2-D world of Flatland. In this world, we demonstrate that the inability to turn their heads (left or right) prevents them from seeing the 3rd dimension directly, but that a shadow cast by the dimension, would be seen, either on the box itself or on the ground. A number of illustrations of how we might see a four dimensional cube are included. The last one is how it might appear if it was unfolded from itself. If this is indicative of reality, what conclusions might we draw from this?

Topic by Goodhart    |  last reply

My Neighbors Are Mad: My Guitar Amp Headphone Jack Doesn't Work.

I have the same problem with a Phil Pro amp for an electric guitar. I have a 1/4 inch jack to 3.5mm adapter, I know it works because I use it on my turntable amp, but when using it on the guitar amp I just get the amp speaker sound, no sound on headphones. I want to learn how to play guitar in the night, so this is crucial to me.

Question by laubredelcosmos    |  last reply

Water softner keeps overflowing!

Hello!hope everyone is safe and healthy!i have a water softner in my celler for well water.we pour our bags of salt but i notice that the water overflows past a certain point and leaks.any way to stop this?(im from the city lol).and also anyway to remove salt from the walls?the splashing hit the dry wall so its bubbling full of dry salt.thanks!

Topic by gholloway    |  last reply