RC India

Hello everyone I made a mini hot wire cutter which is not working I tried using those 9 volts batteries 2 of them and the battery chargers in which you should remove the battery from the phone to charge it.
The lights in the charger did not glow.
the batteries became hot.
I used guitar wire 1st one of both electric and normal bought it from sapteshwara musicals luz corner.
https://www.google.co.in/maps/preview?hl=en#!q=sapteswara+musicals&data=!1m4!1m3!1d3254!2d80.267384!3d13.0383246!4m15!2m14!1m13!1s0x3a5267c9a2ab4f37%3A0x1439eedf0b841979!3m8!1m3!1d208280!2d80.2069211!3d13.0340798!3m2!1i1366!2i643!4f13.1!4m2!3d13.039851!4d80.267629 (https://www.google.co.in/maps/preview?hl=en#!q=sapteswara+musicals&data=!1m4!1m3!1d3254!2d80.267384!3d13.0383246!4m15!2m14!1m13!1s0x3a5267c9a2ab4f37%3A0x1439eedf0b841979!3m8!1m3!1d208280!2d80.2069211!3d13.0340798!3m2!1i1366!2i643!4f13.1!4m2!3d13.039851!4d80.267629)

pics

more

Try using a 12V 2A power supply to heat the wire

asked the near by famous electrical shop for that cool stuff but they don't stock it any idea from where can i get it.
also I have an old computer lying around how do i take out the power supply from it and then use it for my work any video tutorial will be of great help

Pics for the charger

Bro at your age, experimenting with different power supplies and electricity, i wouldnt suggest it.

Make your hot wire cutter battery compatible. Here is a tutorial for this: http://www.instructables.com/id/Hot-Wire-Foamcutter-Battery-Powered/
just make a handheld version of this.
You can use D-cells too. 2xD cells+nichrome wire.
Like this: http://www.amazon.com/Crafters-Hotwire-Styrofoam-Operated-Projects/dp/B004E97LCI/ref=sr_1_1?s=toys-and-games&ie=UTF8&qid=1326203833&sr=1-1

Here is a video of one such D-cell cutter:
http://www.youtube.com/watch?v=7E4RFE1EUSg

Nitesh,
What you need is high current, and not just high voltage. In short lots of power (I² * R) for your experiment. Notice that I (current) is squared so a small increase in current will drastically increase power, resistance being the same.

"That cool stuff" is easily available at any computer shop. Get a 12v min 2A switched mode power supply adapter like santhosh-r has suggested, and you should be good to cut foam. With a computer supply, I think it might shutdown as the anti shortcircuit protection will kick in, but I will leave others to comment who've already done this. You might need to use a very high wattage resistor in series with the wire.

In simple words, a 12v 2A power supply works just fine for the cause, get hold of one.

Hope that helps.
GS

PS: Battery solution is ideal, just don't blow up things, and be safe. ****And dont try to use any type of Lithium batteries to do that - NiCD, NIMH or Pb only****

rc neil bhaiya you are great it cuts it butter smooth.
thanks thanks
its working with those camera batteries thanks everyone for your suggestions

No problems mate, not almighty never want to be and never will be.

ok then
one problem the thermocol gets stuck in the wiire why is it so
pics of the cuts which i did using it

ATX power supplies can source upto 25A and more, you may have to limit the current draw to keep the hot wire from burning up.
Converting the desktop PSU into a bench-top unit is fairly simple, but if the computer was used recently, be sure to discharge the larger capacitors within the PSU before handling the internal circuitry, I got a nasty jolt from one of those.

Follow this instructables: http://www.instructables.com/id/ATX--%3E-Lab-Bench-Power-Supply-Conversion/
 :thumbsup:

Instructables are just great
It has not been used for more than 2 to 5 years :giggle:

It's way to complicated I will use an power adapter which we get in stores. however I have my hot wire cutter ready so don't need to worry.
Which one of these is better for our use
 http://www.ebay.in/sch/i.html?_sacat=0&_from=R40&_nkw=dc+12v+2a+power+supply&_sop=15 (http://www.ebay.in/sch/i.html?_sacat=0&_from=R40&_nkw=dc+12v+2a+power+supply&_sop=15)

http://www.ebay.in/itm/DC-12V-2A-24W-Switch-Power-Supply-Driver-Transformer-CCTV-or-LED-Strip-Light-/111031395184?pt=IN_Home_Appliances&hash=item19d9fca370&_uhb=1#ht_5065wt_1271 (http://www.ebay.in/itm/DC-12V-2A-24W-Switch-Power-Supply-Driver-Transformer-CCTV-or-LED-Strip-Light-/111031395184?pt=IN_Home_Appliances&hash=item19d9fca370&_uhb=1#ht_5065wt_1271)

http://www.ebay.in/itm/DC-12V-2A-24W-Switch-Power-Supply-Driver-Transformer-CCTV-or-LED-Strip-Light-/261119878398?pt=IN_Home_Appliances&hash=item3ccbf524fe&_uhb=1 (http://www.ebay.in/itm/DC-12V-2A-24W-Switch-Power-Supply-Driver-Transformer-CCTV-or-LED-Strip-Light-/261119878398?pt=IN_Home_Appliances&hash=item3ccbf524fe&_uhb=1)

http://www.ebay.in/itm/100-240-V-AC-DC-12-V-2-A-Switching-Converter-Adapter-Power-Supply-Charger-DTH-/251231965505?pt=IN_Computer_Components&hash=item3a7e979141&_uhb=1#ht_2772wt_1037 (http://www.ebay.in/itm/100-240-V-AC-DC-12-V-2-A-Switching-Converter-Adapter-Power-Supply-Charger-DTH-/251231965505?pt=IN_Computer_Components&hash=item3a7e979141&_uhb=1#ht_2772wt_1037)

check this,
http://www.flitetest.com/articles/hot-wire-cutting-foam
a bit costly but Failproof way.
requires a esc and servo tester.

my wire burnt because of using 12v 1a power supply lying around my house.

So this is what happened I searched my house for a power supply and got one which was 12v 1a I thought lets connect this to my cutter but it was a laptop one so i put one wire inside and took the other one and put it outside now i used tape. After this what ever happened was a nightmare all this happened in 5 seconds flat. Then i connected it to a ac power socket and turned the switch on The wire became red hot and then suddenly burnt then i switched it off Thank goodness there was no damage It really scared me to death. those 5 seconds were terrible

The 5 seconds are over now. Take precautions, and do that again a couple of times ;) Confidence will take over fear  :thumbsup:. *Be safe*.

On a serious note, the wire went red hot because a lot of current passed through, increase the length of the wire between the contact points or reduce the voltage until you get the right heat setting. Read up how a potentiometer works. The foam is sticking to the wire because the wire is not very hot. If the wire is much hotter than required, you will have to move it faster through the foam (increased feed rate). If it is not as high as required, it will stick to the foam and you will have to go slow... but a minimum temperature is required, you will need that setting corrected first.

Thanks sir will take care of safety next time
I guess the reason of burning of the wire was because of the thickness and length. The length was something around 5 to 8cms and it was electric guitar's first wire which is quiet thin.

Can anyone tell me that what power supply unit should i use for a 15 to 16cm wire http://www.instructables.com/id/Hot-Wire-Foam-Cutting-Nunchucks/ (http://www.instructables.com/id/Hot-Wire-Foam-Cutting-Nunchucks/) it is classical guitar wire 2nd string

nitesh! get yourself a servo tester!

how will a servo tester be usefull for this ??? ??? ???

(http://static.rcgroups.net/forums/attachments/4/4/0/9/a3269392-100-Servo%20tester%20hotwire.png)
try this.... this should work for you as a variable heat control... otherwise just use longer wire.. basically you want to increase the resistance to that sweet spot, where the wire is hot, but doesnt burn...

Thanks a lot got the diagram Thanks a lot I just can't understand one thing what is that esc doing over here