# Need Help in assembling an electrical resistance heater

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1. Apr 10, 2016

### ThomasMHeat

Hello

Im looking to build a very small electrical resistance heater. It should produce no more than 1 to 3 degrees of heat. This is for a personal project of mine.

I need to know what types of materials I need to use. Id like the device to be both battery powered and plug in.

Can anyone assist?

Thank you very much

2. Apr 10, 2016

### anorlunda

Degrees are the wrong units. Temperature depends on how well insulated things are. You should ask about watts.

Watts needed spend on the size of the tubby being heated. Are you building a hand warmer or a house warmer?

3. Apr 10, 2016

### ThomasMHeat

you would think of it as a hand warmer - something very small. NOT to heat an entire house at all.

4. Apr 10, 2016

### anorlunda

Check Cabelas or Campmor. I'm sure they sell battery powered hand /foot warmers.

5. Apr 10, 2016

### ThomasMHeat

lets say that i wanted to build one from scratch.
What would I need?

6. Apr 10, 2016

### anorlunda

OK, start with the relationship $P=\frac{V^2}{R}$. If you have a 9 volt battery, you need an 81 ohm wire to make 1watt.

Look up heating wire on eBay. Select one where the Ohms per foot resistance of the wire, times the number of feet in your heater comes out to about 80 Ohms.

7. Apr 10, 2016

### ThomasMHeat

Thank you very much

and this production of 1 watt of power should produce heat between 1 or 2 degrees?

8. Apr 10, 2016

### Averagesupernova

By no stretch am I an expert on how to determine how much extra heat is needed in relation to how much heat you are losing. But I do know that this is an issue and I also know it has been implied by a previous poster in this thread. You seem to ignore this.

9. Apr 10, 2016

### ThomasMHeat

how many degrees of heat does 1 watt produce? Can this be answered? Yes or No.

10. Apr 10, 2016

No .