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I was thinking of buying a 2 in by 18 heating blanket for bending rope binding.The test samples I tried to bend on my luthiers alum bending iron failed.When I looked at the omega website the bending blankets come in 2.5 watts 5 and 10 watts. Does anyone know what that translates to in temp i.e. degrees F. ?? My plan was to make a plywood circle and bend the rope binding around it using the small heating blanket. Anyone out there done this?

No .. but I use the 2.5 watters exclusively .. I see no need for the 5 watters. The 2.5 will get wood up to 300 degrees or so in a couple minutes, and the wood is ready to bend. I use the 2x18 for small binding pieces in dedicated molds for armrests and ribrests.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

All the blankets get hot enough and pretty quickly. The watts per square inch relate to how many amps they will draw. For a typical 36X6 inch blanket the 10w/sq.in. might draw 18 amps under full load, and overload a 10 amp circuit or one with multiple appliances being used at the same time. A 2X18 inch blanket would draw considerably less.
I use the 2.5 w/sq in. blanket and it works fine.

Thanks for the explanation on amp draw.I have a watlow 6 by 36 I run it at abt 325 , and can only use 1 line on a 15 amp circuit.The bigger blanket is probably drawing close to the 15 amp limit, as the plug wire is always warm.

What is the watts per square inch of your blanket? I ask because I have a 6 x 36" Watlow blanket (2.5w per square) and am relocating my shop space. I'm wondering If I will have trouble with the 15 amp circuit that is run to the area I want to do my bending in. I suppose I could move the bending station to be by the 20 amp circuits but I'd rather not. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Bryan I bought the same heating blanket from watlow, when we lived in valley park. Personally I have used the 6by 36 often ,it is hooked up to a large dimmer switch.,I.m guessing but I never let it get over 350 on the blanket , I use a thermometer, and then shut it off, if the side is not bent when cooled .I give it another try.I would err on the side of caution, and use 20 amp line.When I ran my plug through a 4 plug circuit box,it would frequently, once heated up, shut down.Now I use it with a heavy duty extension cord on a 15 amp line. Havenot tripped the circuit breaker box

Thanks Ernie. I'm getting ready to build the counter space for the shop now, so I still have some flexibility. It would have been nice if we had talked about this before the drywall was done.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I use 5 watts per in and use a controller. That allows you to dial in the temp you want.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

bryan I have a ham radio licence for 48 years. A really good friend is a master electrician.If you have a question PM me and I can run it by my electrician friend. ernie

well .. do the math here - 6x36 = 216 ... x2.5watts per = 540 watts. A 15 amp circuit at 120 volts gives 15x120=1800 watts of potential power ... you wont even cause a blip using that blanket... no need for 20 amp circuit.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Tony you are correct.in your calculations. I had an electrical fire in a home in van bc, that had a seperate circuit for the dryer.Unbeknownst to me, the previous owner had spliced in another line that was in my then work area.Since then I always err on the side of caution especially when it comes to electrical outlets, and listening to horror stories from my electrician friend.

Thanks Ernie and Tony. I often run my blanket and bending iron at the same time. Looking at the calculations Tony provided, I should still have enough "headroom." I doubt, I will be using much else from that circuit if I am busy bending so I should be fine. The first time I trip the breaker (if that ever happens) I will re-evaluate. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I also have all my wiring at 20 amp circuits and underloaded. I would rather a box full of breakers than an overloaded circuit. I don't have any 14 wire in my house or shop. I know it may be safe but I would rather be on the safety side.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it