Battery safety

Hi guys, I was wondering if it's dangerous to touch two wires hooked up to a 9v battery to each other. They heat up really quick, could they make the battery explode or do something else bad if left like that for any long period of time? I tried to search for the answer, but couldn't find it.

Topic by Lithium Rain   |  last reply


Fire Safety!

I became interested in hobby electronics after seeing this instructable: Light BarWith projects like this, the more components I buy, the cheaper each component is (ex: buying LEDs in bulk) so I will likely end up with more parts than I would want for myself. If I make a lot of these things (or similar projects) and give some to friends, how can I make sure that they are completely safe?

Topic by NOOBLMAO   |  last reply


Basic Electronic Safety

Hello all! I'm beginning down the route of hobbyist electronics. As to basic safety precautions I'm really quite unsure. I know inside many electronics parts and devices (For example, a TV one would strip for parts,) there are many nasty chemicals. I don't want to get lead poisoning or any other sickness. If you could point out some safety precautions, I would be incredibly grateful (Ex. Always wear gloves, wear a mask when soldering, when stripping a TV...., etc.). Thanks for your time and help!

Topic by I Am That Guy   |  last reply


Safety, Electricity and Death

I came across this AC safety info and found it useful enough to share. Link: www.cdc.gov/niosh/docs/98-131/overview.html FTA: 1 mA Barely perceptible 16 mA Max current an average person can grasp and let go 20 mA Paralysis of respitory muscles 100 mA Ventricular fibrillation threshold 2 Amps Cardiac standstill and internal organ damage 15/20 Common fuse or breaker opens circuit I later found this DC info... Link: www.allaboutcircuits.com/vol_1/chpt_3/4.html FTA: "AC ... is 3 to 5 more dangerous than DC of the same voltage and amperage." Slight sensation felt at hands DC Men: 1.0mA, Women: 0.6mA 60 Hz AC Men: 0.4mA, Women: 0.3mA  ... Painful, but voluntary muscle control maintained DC Men: 62mA, Women: 41mA 60 Hz AC Men: 9mA, Women: 6mA ... "In industry, 30 volts is generally considered to be a conservative threshold value for dangerous voltage. The cautious person should regard any voltage above 30 as theratening, not relying on normal body resistance for protection against shock."

Topic by milsorgen   |  last reply


Tesla Coil Safety?

My high school recently had an engineering fair, and my friend had built a tesla coil. Its has multiple spark gaps, an RF filter (I think thats what its called), a 120 to 20000v transformer, and toroid top-load, if any of that matters. We/I would entertain ourselves by standing away from the coil and holding a fluorescent tube (by the glass with bare hands, not by the contacts) near the top-load and watching it light up. Even though I was well away from the coil, my forearm muscles would twitch, especially it the coil spark hit the contact on the other side of the tube. Then if anybody touched me, both of us would feel a shock and the same slight twitching (the same kind of twitching you feel from those electric muscle stimulators with the pads you put on sore muscles). We even set up a chain of about 5 people holding hands, and all of us would feel a shock, even though only the first person in the line (aka me)  was holding the fluorescent tube near the coil, with my hand on glass, no where within range of the streamers coming from the top-load. Now for my question: is this dangerous? (I know its non-lethal, im talking about my nerves) And what exactly was happening? because it was not an incredibly large coil, and i know that the field of a coil is much larger than the actual streamers. I also read somewhere that insulators dont work the same at incredibly high voltages. I think what I was feeling was the skin effect, and the charge came from the excited electrons in the tube. If my ideas are correct, then wouldn't me holding the tube be just the same as if i had just put my hand near the top-load and let the streamers hit me?

Question by masterbuilder   |  last reply


How does instructables address some projects that I see have some serious safety and liability issues?

Some projects that are on the instructables website have some serious safety and hazard concerns. In particular electrical and electronic projects that interface with 120 volts or higher. Though many of these projects are incredibly creative and brilliant, some oft these projects could put people at risk along with their associated liability.The "instructables" organization itself might be liable as well if it has not done more than some superficial notice to it's membership. I suggest that projects that could be hazardous be inspected by any controlling authority (such as building and safety) prior to their being displayed on the instructables website.

Question by SeanFeeley111   |  last reply


Capacitor-bank safety issues

Okay, so I'm going to be the wet-blanket old guy.... Has anyone considered adding a topic to this group (or an I'ble) on electrical safety with supercaps? Even the low-voltage ones put out tremendous current, enough to put you into convulsions or stop your heart (50 joules) if applied correctly. These devices are amazingly cool to work with -- better than batteries when you need high current, outstanding AC line filters, and terrific party toys when you need some bang for your buck. They can also turn around and bite you on the arse without warning...

Topic by kelseymh   |  last reply


Help with sketch, and a safety question? Answered

The model I'm building calls for 13 LED's and fiber optics running from about 6 more LED's. I have managed to get them all running on one arduino and breadboard, will this be safe? The arduino will run on a mains adapter and has a pot for flashing speed, a pot for brightness, and an on/off switch. After lots of trial an error and a lot of luck I have the other LED's acting just as I want. But I am having trouble getting 11 and 12 to stop flashing, any ideas? int sensorValue = 0; //make a variable where you can store incoming //analog values void setup(){ pinMode(12, OUTPUT); //tell arduino what you'll be using these pins pinMode(11, OUTPUT); // for (output). pinMode(10, OUTPUT); pinMode(9, OUTPUT); pinMode(8, OUTPUT); pinMode(7, OUTPUT); pinMode(6, OUTPUT); pinMode(5, OUTPUT); pinMode(4, OUTPUT); Serial.begin(9600); //initialize serial } void loop(){ //we put the code we want executed in a loop Serial.print("sensor = " ); //sends what's in quotes via serial Serial.println(sensorValue); //sends our variable (sensorValue) //via serial digitalWrite(12,HIGH); // lights the led digitalWrite(11,HIGH); digitalWrite(8,HIGH); digitalWrite(4, HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(4, LOW); delay(15); digitalWrite(6, HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(6, LOW); delay(15); digitalWrite(5, HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(5, LOW); delay(15); digitalWrite(7, HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(7, LOW); delay(15); digitalWrite(5, HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(5, LOW); delay(15); digitalWrite(10,HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(10,LOW); delay(15); digitalWrite(9,HIGH); sensorValue = analogRead(0); delay(sensorValue + 25); digitalWrite(9,LOW); delay(15); }

Question by lifeofB   |  last reply


Bypass safeties in electronic Neon Transformer

I have a neon sign transformer that i would like to use for high voltage projects. The problem is it has an electronic safety circuit that (I believe) checks to see if there is a neon tube is attached.  Does anyone know how to bypass the safety system? the transformer box is full of insulating tar so accessing the electronics is near impossible. when turned on it sends out several short HV pulses and then the warning light illuminates, it seems to be searching for some type of load. 930CPX120 ALLANSON 9000V 30MA NEON TRANSFORMER,

Question by BlitzkriegBrain   |  last reply


Safety Warnings -- how to do it right!

I saw this on the MAKE blog today.  It is, I think, the single greatest effort at a properly respectful (to the intelligence of the user) safety warning that I've seen.  Kudos both to the tech writer who came up with it, and the lawyers who had enough common sense to release it into the wild. My only complaint is that on SparkFun's Web page, the instruction manual is a completely inaccessible JPEG image.  Perhaps part of being "safe" is not allowing anyone with low vision or who reads a language other than English, to know about the product?  (Yes, I've contacted them directly about it.)

Topic by kelseymh   |  last reply


how to bypass the safety on a battery charger?

Ive been working on a cd welder for battery tab.. very simple car audio capacitor with a battery charger. today i rebuilt the whole thing with new leads wiring and new battery charger that will shut off when it hits a full charge. now it wont charge at all because it apparently wont charge anything thats not a car battery with proper voltage already existing. since the capacitor dumps the charge and leaves nothing, the charger just thinks there is nothing there. can anyone give me a crash course in float chargers and how they work so i can single out what i need and bypass everything else

Question by snowfox222   |  last reply


Garage door safety sensor wiring?

I believe it is an infrared sensor with two wires on each. I have wired them to a 120V plug and the LEDs on them turn on and my motor spins slightly (probably just because it is a 120V motor and it's not getting enough electricity) but I try to line up the sensors and they do nothing different even when crossed. What I want to happen is for the motor to remain off until the beam is crossed. Once crossed I want it to spin and to keep spinning until I disconnect it. I would really like to put an alarm on it so when crossed an alarm goes off. Does anyone know the additional things I need and how to wire them? Thanks

Question by chiefs543   |  last reply


Mains Ground Safety for Power Supply? Answered

I'm trying to build my first switched mode power supply. I'll be using it to drive two 24v 50W heating elements. I don't want to use a transformer. The design I have so far seems to work well in simulations, but I need some advice regarding mains ground. The control electronics will be operated on power from a small transformer. This provides isolation from mains. I've done this a million times.  However, the mains power connects directly to the loop that produces the 24V signal. This is the loop after the FET, containing a diode, inductor, and capacitor. The wire coming from this loop and going to the comparator is where I'm having trouble. This is a voltage sensing wire and carries very little current, and is used by the comparator to produce negative feedback. This feedback loop is what allows me to get 24V from 120V. The comparator is powered by the 12V isolated supply. In order for it to sense the voltage properly, the comparator's ground must be at the same voltage as the power supply's ground. But the power supply's ground is tied directly to mains ground. Is that safe? Am I allowed to do that? In mains wiring in the US, the left notch is neutral, the bottom hole is ground, and the right notch is hot. Neutral is basically ground, except ground is connected to the actual ground and neutral is this mysterious thing I probably don't completely understand. Is it safe to use it as ground? What if the person using this circuit flips the plug over and suddenly the circuit's "ground" is fluctuating wildly between +/- 120V? The circuit may function just fine, but someone using a switch or knob connecting to ground could get a nasty shock. How do I make sure the ground of my circuit is always connected to actual ground? Do I need to preserve the isolation of the control circuitry? I know how to use Gate Drive Transformers for the FETs, but the sense wire for the comparator still needs to have both halves of the circuit with their grounds at the same voltage. Any advice is greatly appreciated.

Question by laserjocky   |  last reply


How should I protect my eyes when working with a laser?

I want to built a laser cutter and have bought a 7W laser for it. How should I protect my eyes? What is important in building it to make it safe / have no risk left to hurt my eyes...

Question by macmoritz   |  last reply


Cats eyes road markers? Answered

Over the years I have come up with a variety of ideas - some Impractical, some worked and many that never went beyond the thought or drawing stage. A long time ago I thought this was a good idea, with no budget or inclination to action it practically I put it up here for comment/critique In the UK and many other countries the centre and edge of the road is marked with reflective dots. In the UK we call these cats eyes as the inventor was supposedly inspired by the way a cats eyes shine in the dark. However good though they are they only reflect as far as your light beam reaches. On dipped beam this may not be that for ahead and with the sort of traffic we get in the UK you hardly every get to use the main beam. My suggestion is to cut a slot down the middle of the road and lay in it a fibre optic cable linking every cats eye in groups of say 50 or 100. The ides is as the diagram shows the Fibre optic carries your dipped head light far further then it would normally shine without the risk of dazzling other road users. I think that this would significantly improve road safety at little cost if done when road refurbishment was carried out anyway as at this time the cats eyes are often removed and replaced. The cats eyes could be simpler, lower profile and possibly cheaper to makeas they would only need to be a plastic holder for the fibre.

Question by rickharris   |  last reply


Forced Air Respirator?

I have a a AOS Safety respirator with P100 cartrideges and i think it is time to replace the cartridges, i have used it for hobbies when airbrushing, lathe working, fiberglass sanding, and enamel spray painting.  How do i tell when the cartridges need to be replaced?  Also i was wondering, would it be possible to convert it to a forced air respirator, by taking an old pair of cartridges and cutting out all the filters and stuff and attaching to air hoses, one to each cartridge and using dryer duct alluminum tape to make it air tight.  Then attaching some type of fan to it, or attach it to the houses a/c vent? Would this work?

Question by snowluck2345   |  last reply


How can I fit a Semi Truck horn onto a bike or a Vespa? Answered

Infmom on Lifehacker had an idea here - http://lifehacker.com/comment/16894792 - and personally I think it might safe a few lives. I'd love to hear anyones' thoughts on this.

Question by Aquilla   |  last reply


UsbSafe² . Usb Safety Device! OpenSource, EEvblog

I have designed a new usb anti Juice Jacking device which will protect your private data from harmful attacs. It will also protect your Hardware by over voltage protection and current monitor. Check out the video below when Dave from EEVblog finds it in the mailbag. Also a short demovideo is attached!! Functions has been added and the features now are: 1 Anti Juice Jacking function. 2 OVP. Over voltage protection. 3 Current fuse functionality. 500mA/900mA/1500mA/2100mA/2400mA This project will go live ASAP at: https://www.crowdsupply.com/karoly-simon/usbsafe2 At launch design files will be public! Navigate to prelaunch page and subscribe for release info!

Topic by Karoly Simon 


Safety of laser cut foamboard (fumes, etc)? Answered

So I cut some elmers 3/16" foam board today on our schools laser cutter- it gave off some nasty fumes but luckily most of it was ventilated out of the cutter. My concern is that inhaling the fumes (or the low-volume fumes i got from whatever smoke was left in the laser cutter), will be pretty bad for you. I dont know how toxic the fumes are from laser cutting foam, but my guess would be pretty bad. I also read somewhere that heating the foam up produces a lot of toxic byproducts, one of them being cyanide... Is this stuff safe to handle? I did feel a bit "foggy" afterwards, and had a slight pain in my chest, but not a lot...Thanks!

Question by astroboy907   |  last reply


Can playdoh or clay be microwaved safely? Answered

Pretty simple, I was just wondering if either is microwave-safe. It would be for no more than 2 minutes...I wanted to use them as a mold. Melt probably?

Question by crearc   |  last reply


What will happen if i use a capacitor that has a farad measurement that is less than what is required ?

The voltage limit is properly matched, only the farad measurement is not the same. IMPORTANT WILL THE CAPACITOR EXPLODE?

Question by La Tour Rouge   |  last reply


are high power ir leds dangerous? Answered

Im experimenting with ir motion sensors and im think i have a working model, but then i realized i would have a ir led on at almost 150 ma and i didn't know if that was safe, so i managed to reduce it to 10 ma and still work, but then i realized that if i didn't know how dangerous ir leds are, then any level could be unsafe for all i know (i came to that realization after i changed the circuit because im smart like that) i couldn't find any safety info on ir leds, just ir lasers, is there a certain power to distance ratio or anything i should know? aside from not shining it directly into my eyes (im not that far-gone)

Question by the judge   |  last reply


Is drinking water with dry ice in it dangerous? Answered

In Science class we had some dry ice, and a friend put some in the bottom of a class of water, then drank the bubbling water. He said it was safe, and others did it with no apparent ill effects. I tried a little taste of the water and it tasted like mineral water. Is this safe?

Question by ilpug   |  last reply


Why do some capacitors have polarity? Answered

(Asked once already, but for some reason was not visible.) That is sort of a blanket question. I'm wondering: 1) why only some, and not all or none? 2) what (in their physical structure) causes them to have polarity? 3) why do we make ones that have polarity? Is there something prohibitive, like cost, or safety, making it so in the production? (okay, not safety, as may attest anyone who has seen a reversed capacitor explode.)

Question by V-Man737   |  last reply


How do I know if I need laser googles for my laser? Answered

How do I know if I need laser googles for my laser? From what MW is it recommended to use laser safety googles? Are there goggles that fit specifically for a color of a laser? My laser is a 50MW Green laser Thanks in advance :) This is the laser: http://www.ebay.com/itm/12mm-10mw-30mw-50mw-100mw-200mw-532nm-green-dot-laser-module-driver-spring-wire/311028329241?hash=item486abbab19

Question by Yonatan24   |  last reply


Is it safe to use a broken LCD TV without the liquid crystal panel in as a lamp or flood light? Answered

Months ago I found a LCD TV at the dump and thought I could breath new life into it. Turns out I could replace the broken panel for around $200. It isn't that great of a TV and I don't have that much money for something that may or may not work.

Question by s   |  last reply


How to get past Windows Live Family Safety?

It's reallyyyy annoying and I prevents me from viewing TONS of sites... it record what I'm doing right now also... Greattt...

Question by austinburke.   |  last reply


Are there other ways to cool an object to 77 K (−196 °C; −321 °F) without use of cryogenic fluids, like liquid nitrogen?

 I am looking for a way to be able to keep an object below 77 K, while maintaining an airtight container. This cannot be obtained with cryogenic fluids like liquid nitrogen, as it becomes highly explosive and dangerous. Therefore, I need a way to keep an object below 77 K in an airtight container, safely.

Question by gabe94   |  last reply



How to test jewellery for cadmium?

These days a lot of jewellery is testing as containing dangerous levels of lead and cadmium, mostly Chinese imports.  How could a consumer test jewellery for cadmium, easily and cheaply at home, please?  I can't find anything online about how to test for cadmium.

Question by Lickyboomboom   |  last reply


Tesla's "magnetic wave" communications idea proposed for mine safety

A report in Science Magazine describes a proposal to use Nikola Tesla's magnetic amplitude modulation as a way for trapped miners to communicate with the surface.

Topic by kelseymh   |  last reply


i need to replace a 3 pronged grounded power chord with a 3 pronged grounded jack how do i do this without risks ?

On my guitar amp the ground prong broke out of the plug so i need to replace that with a jack such as one found on a PC power source but i dont know what is positive and negative or how to prevent enternal damage fires or shock * i posted i picture my connector looks like the one on the left only mine does not have leads only contacts sorry if i wasnt clear on what i was saying *i have a second one of these with leads from a computer power source with wire leads but its a little differant it as a blue and brown instead of black and white wires and it also has a small yellow box that connects to bot contacts(excluding ground) which of these will work beter for a guitar amp

Question by fastcar123   |  last reply


how to turn off family safety without logging into the monitors user account?

Hey i'm bella, 16 year old girl gamer that only wants to play wizard101 but my dad installed family safety into my laptop that now wont let me do anything, and my dad is never here so I cant get the password for it, so how can I get family safety off my laptop or some how restart my laptop to get the program off it? please answer me.

Question by gamerchickquest   |  last reply


Solder fume extractor with carbon and HEPA filters?

I have been reading about the subject, and most articles tell that carbon filters are good for solder chemicals, fumes and odors, while HEPA filter are designed to remove dust, allergens and micro-organisms from the air. Supposedly, solder fume extractors should use both filters for an efficient filtering of the chemicals. Is this correct? Thanks for your time! Source: https://www.google.com.ar/url?sa=t&rct;=j&q;=&esrc;=s&source;=web&cd;=4&cad;=rja&uact;=8&ved;=0ahUKEwiWkOu6v8nPAhUIPJAKHXhDCgEQFgg1MAM&url;=http%3A%2F%2Fwww.solderconnection.com%2Fspecsheets%2FLead-Free_Solder_Fumes_Increase_Need_for_Fume_Extraction.pdf&usg;=AFQjCNHqetU2dZG3hSaRNmPIl1LhUObshw (The link redirects to a PDF file!)

Question by superpanchox   |  last reply


Hooking up my safety 1st camera to a regular tv? (and another question)?

I just bought a safety 1st camera at a garage sale for 30 bucks. It sends a black and white image and audio, the lense is surrounded by 18 IR LEDs. I've tried scanning available channels on my regular TV, and didn't recieve the image, and the mini TV doesn't have any outputs. Is there a relatively easy and cheap way to get the signal? I am also wondering why the IR LEDs glow cherry red, I've heard that some few people can see near infrared light, but 2 other people can see it roo. Is it because they are older LEDs

Question by XOIIO   |  last reply


Issues and safety precautions to take with a 50-70 feet 12v bus line?

Hi  i am thinking of building a emergency LED setup with some 1w or 3w LEDs which will be connected to a 12v bus line powered from a deep cycle battery. I will be using a fuse between the battery and the bus line. I am thinking of placing a cluster of LEDs every few feet(7-10 feet). Each LED will be powerd using a mr16 LED driver using power from the bus line and the driver should consume somewhere around 350ma of current. Each LED will be mounted on a heatsink. Max LEDs in a LED cluster will be 3 no.s . Total current used when all the LEDs are on should be around 6 amps max. So, the question is, what kind of safety issues should i look out for and what type of wire i should use for bus line and the lines to leds. Also, should i be using relays for LEDs or will switches be fine? And what precautions should i take  ?

Question by bipl12   |  last reply


Soduim hydroxide container? Answered

Is it safe to keep sodium hydroxide (NaOH) in a glass container or is PYREX necessary for safety? 

Question by jonrb   |  last reply


Why dont they use alcohol in closed system steam engines? Other than safety?

By closed system i mean constant mass of working fluid.  i.e. no steam leaving system, like an air conditioner. My point is that alcohol has a lower boiling point that water, (some kinds can boil from the heat of your hand!). SO other than the safety problem of alcohol being flamable, alcohol could operate with a lower heat input than water.    With the addition of a cold resivoir, the closed system alcohol steam engine could work right? Or why not use a refridgerant gas in a closed system steam engine cycle,? >Which would effectively absorb the heat input any ideas? addition*  I mean for use in any steam engine with a closed loop cycle, like the Rankin cycle   http://en.wikipedia.org/wiki/Rankine_cycle

Question by MechEngineerMike   |  last reply


Electronic Neon Transformer project help

I have a neon sign transformer that i would like to use for high voltage projects.  The problem is it has an electronic safety circuit that (I believe) checks to see if there is a neon tube is attached.   Does anyone know how to bypass the safety system? the transformer box is full of insulating tar so accessing the electronics is near impossible.  930CPX120 ALLANSON 9000V 30MA NEON TRANSFORMER, 

Question by BlitzkriegBrain   |  last reply


On capacitors and polarity.

(Asked twice already, but for some reason was not visible.) That is sort of a blanket question. I'm wondering: 1) why only some, and not all or none? 2) what (in their physical structure) causes them to have polarity? 3) why do we make ones that have polarity? Is there something prohibitive, like cost, or safety, making it so in the production? (okay, not safety, as may attest anyone who has seen a reversed capacitor explode.)

Question by V-Man737   |  last reply


How is a large building wired up? Answered

So, recently, I was at school, and trying to use my laptop charger ( I was the only person in the room to be doing so) However, it didn't work. Using it at home, however, it instantly kicked the RCD or safety switch thing off, switching off everything running off the mains Upon further inspection, I found that the power cable had been damaged, so that the active wire was in contact with the ground wire. My question is, how come the power at school didn't get shut down completely ( the lights were still on, and wall outlets in other rooms around the school still worked) but at home, everything was completely shut down. I thought that there'd be at least a fuse or something, if not a safety switch...

Question by .Unknown.   |  last reply


Max voltage and current for electrolysis of water.

What is max value of voltage and current can be used for electrolysis of water to accelerate the hydrogen production rate within safety limit?

Question by SahilK75   |  last reply


SPyware - The Web Of Trust? ( WOT)

Recently Ive been very jumpy about spyware. it seems that on99% of everywebsite I see, there's a spyware ad in a corner. Ive been wondering how much spyware I've installed without knowing.... Antispyware software is good, but it doesnt always do the whole job. Most only block a program after its already started. Ive heard about the Web Of Trust. Supposedly, its a network or people who rate the safety level of a website. Ater you install the program, a safety rating will appear next to it on google, IE or Firefox. I tried researching it, but I cant find any RELIABLE sources. I was wondering if you guys have heard about this or know of something similar. Im ver worried about spyware and would like to know of other safety precautions. Aso talk about spyware in general here.

Topic by Keith-Kid   |  last reply


What can I do with piezo buzzers/sirens/beepers, switches, safety switchs, and other basic components?

I have some components I really like, but I don't know how to use them!!!  (resistors, leds, 555 timers.. etc.)? relays even?

Question by sjoobbani   |  last reply


How can I get a project of mine into one of those ebook guides? Answered

I created the "5 minute safety light" and "LED lantern/lamp" and would like to know how to get them added to the 5 minute project ebook guide.

Question by javajunkie1976   |  last reply


120v AC to 120v DC

Basically I want very strong electromagnets for a gauss rifle that I can power from a home power outlet... Disregarding safety and efficiency, would a 120vac-120vdc bridge rectifier do what I want it to do? Maybe? Hopefully?

Question by ColinF14   |  last reply


Is there a relatively safe alternative to vinegar and baking soda for chemical reaction volcanoes? Answered

My brother is working on a paper mache volcano experiment for school, and I figured that the instructables community has come up with something a little more creative than just vinegar and baking soda. When I say relatively safe I mean something that doesn't emit poisonous gasses or toxic waste.  Thanks for any help. Update: I'm not worried about the safety of vinegar and baking soda, I added a safety request because I was almost very stupid mixing chemicals without checking about results. I almost created a gas used to exterminate people. There is no need to lecture me on how stupid this was, I already know.

Question by travisttt   |  last reply


Anti-Land Mine Robot

I have started design and concept design on a robot to mark (via GPS and UV paint) and destroy unexploded ordinance in Cambodia.  I am assembling teams for various aspects of the project (mechanical, electronics/power, practical application, coding and programming, construction, etc).  While many people have offered their experience and knowledge, the more people contributing can only benefit the end product.  This is not a money-maker, it's a life sustainer.  I'm looking for people who are interested in using their skills to better someone else's existence.   Though it is brand new, you can visit the project's blog at http://antiminebot.wordpress.com/   All advice is welcomed.  Project updates will be regular. Thank you for your time, Huck

Topic by huck alexander   |  last reply


Need photoelectric/laser switch to trigger a shutter on a digital DSLR. Answered

I need some type of photoelectric/laser switch (similar to that used as a garage door safety device?) to trigger a shutter on a digital DSLR. Break the beam, the switch opens a circuit  and camera takes a picture - pretty simple. Any suggestions?

Question by rdy4trvl   |  last reply


Why does my MOT have a wire from the HV coil connected to the casing? Answered

Hello, I'm busy with making a spot welder from a MOT (microwave oven transformer), but I'm not really sure why and how to ground the MOT. In the picture you can see that a wire from the high voltage coil is connected to the casing which I find to be Really odd. That wire is not really a problem since I'm going to remove the secondary windings, but I'm just interested in an answer to that. Another question is, is it necessary (for performance) to have the MOT grounded? or is it Only for safety that the casing needs to be grounded? (no matter what the answer is, I'm still going to ground it, so it's not necessary to have safety discussions here) thanks in advance, Electorials

Question by DELETED_Electorials   |  last reply