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View Full Version : Smaller Gauges of Wire - Why is it so Hard to Find ?



gunDriller
11th August 2015, 01:13 PM
I have been looking for smaller gauges of wire for a wire-wound tank heater.

36 Gauge 7/44 wire is an example.

7/44 means it is multi-stranded, that the 7 strands of 44 gauge together make 36 gauge.


ALL I NEED - wire that has a resistance of about .2 ohms per foot.

I would rather use copper wire than nichrome or anything like that.

I have already made a few good tank heaters using anywhere from 22 gauge to
30 gauge, using PC power supplies to provide the juice.


It is just rather surprising to do a websearch and find, almost no smaller diameter hook-up wire.

The gauge I want to use is a little like a single strand of Cat 6. I tried using some Cat 6, using just one strand and about 15 feet of wire on maybe 5 volts.

The Cat 6 single strand is just an example of a gauge similar to what I need.


Overall what I will use is about 150 feet of wire.

Since it's for a 300 watt heater, it wouldn't hurt me to use more wire.

If I could find a 500 foot spool that was close to the right number, I would buy that, epoxy it up, add some external connectors, and that could be my heater. (Not the best shape, but it is close to the essence of a wire-wound resistance. They don't really care whether they are wound on ceramic, plastic, or metal.)


Amazon hath failed me.

Santa
11th August 2015, 01:49 PM
Is this the sort of wire you're talking about?

http://www.ebay.com/itm/TEMCo-Nichrome-wire-36-Gauge-80-series-100-FT-0-11oz-Resistance-Resistor-AWG-/381232844881?pt=LH_DefaultDomain_0&hash=item58c33f9051

gunDriller
11th August 2015, 02:26 PM
Is this the sort of wire you're talking about?

http://www.ebay.com/itm/TEMCo-Nichrome-wire-36-Gauge-80-series-100-FT-0-11oz-Resistance-Resistor-AWG-/381232844881?pt=LH_DefaultDomain_0&hash=item58c33f9051

That's close.

This would be more like it -

http://www.alltronics.com/cgi-bin/item/29W086/250/34-Gauge-Green%2C-100ft-Single-Strand-PVC

Then looking up the resistance, 26.9 for 100 feet -

http://www.cirris.com/learning-center/calculators/133-wire-resistance-calculator-table


Wow, the Alltronics website has ads for other websites.

Ad dependence is not a sign of strength - if your business is selling geek tools to geeks.

ximmy
11th August 2015, 02:58 PM
gunDriller, the maintenance guy at our work orders stuff from McMaster Carr all the time.

http://www.mcmaster.com/#standard-electrical-wire/=ygcda0

BrewTech
11th August 2015, 05:21 PM
gunDriller, the maintenance guy at our work orders stuff from McMaster Carr all the time.

http://www.mcmaster.com/#standard-electrical-wire/=ygcda0Huge Brewing industry supplier... Highly recommended, as they have some stuff...

osoab
11th August 2015, 06:02 PM
gunDriller, the maintenance guy at our work orders stuff from McMaster Carr all the time.

http://www.mcmaster.com/#standard-electrical-wire/=ygcda0


Huge Brewing industry supplier... Highly recommended, as they have some stuff...

Don't forget Grainger. They sell the kitchen sink (http://www.grainger.com/category/ecatalog/N-1z0dxrz) too.

palani
12th August 2015, 06:25 PM
http://www.ebay.com/itm/Litz-wire-10-46-for-crystal-set-coil-Double-layer-200-/160614959981?pt=LH_DefaultDomain_0&hash=item256565cb6d

10/46 ... but they seem to have quite a few other combinations.

gunDriller
13th August 2015, 05:15 AM
http://www.ebay.com/itm/Litz-wire-10-46-for-crystal-set-coil-Double-layer-200-/160614959981?pt=LH_DefaultDomain_0&hash=item256565cb6d

10/46 ... but they seem to have quite a few other combinations.

That looks real good.

The load will be 115VAC. Not high enough to need wire that accounts for frequency effects, but what the heck.



Need overall resistance of 44 ohms.

Design is for 300 watt resistor and 115 VAC load.

46 Gauge Wire has resistance of 4.2 ohms per foot. 10 in parallel, as with this kind of multi-stranded wire ==> .42 ohms per foot.

For 44 ohms, a little over 100 feet.


I guess that 200 foot roll will be enough, but I will have to be real careful how I terminate the ends.

Feedback welcome.

Going to let the calculations sit for a second while I get the day started.