BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

While it hasn't really cooled down a lot here in Virginia Beach, it was just chilly enough that I was wanting a heated jacket. I looked at buying one and decided I wasn't that keen on shelling out the $$$ for one. So, I looked at numerous descriptions of homemade heated gear. I made my own and am pretty happy with the result. Here's what I did..

Walmart Jacket - thin fleece for $10

About 2 yards of craft fusible interfacing material - $5 at Walmart (something like the link below)
https://www.walmart.com/ip/808-Craft-Fu ... /641470782

100' of 30 awg stranded hook up wire at Amazon - $15
https://www.amazon.com/gp/product/B0711 ... UTF8&psc=1

Speed Controller Motor with potentiometer, PWM at Amazon- $19
https://www.amazon.com/gp/product/B071W ... UTF8&psc=1

Coax Pigtail Power Connectors (5 pairs) at Amazon - $7
https://www.amazon.com/gp/product/B076N ... UTF8&psc=1

Battery tender fused ring connector at Amazon - $6
https://www.amazon.com/gp/product/B000N ... UTF8&psc=1

The idea is that this works on the resistance from the small wire and you use Ohm's law to calculate the wattage you get from a particular length of wire with a known resistance. The 30awg wire has a resistance of 0.1 ohms per foot. So, 40' gives you 4 Ohms. This gives you 3.43 amps from a 13.7 volt battery (13.7volts / 4 ohms) and 46.92 watts (3.43 amps X 13.7 volts). So, 2 in parallel should be roughly double which is 93.85 watts. That seems pretty consistent with commercially available jackets. A shorter length of wire will give you more heat.

I measured out two 40' sections and then routed the wire on one side of the interior of the jacket along the back, front, and sleeve forming loops that didn't cross about an inch apart. I held it down with blue painters tape and left the ends near the inside of the left pocket. Repeated with another 40' strand on the other side. I cut out sections of the fusible material to match the jacket sections and then damp ironed these on. This sealed the wires between the jacket and the fusible material and keeps the wire from being directly on you.

The wire is very thin and hardly noticeable when wearing the jacket.

I stripped the ends of the wire (hard to do without a 30g stripper) and soldered the ends to a coax pigtail I poked through the jacket pocket and knotted to keep it from pulling out. One end of the right side and one end of the left side to the positive and then the other ends to the negative. Shrink tube to water proof.

I wanted a power controller to be able to turn it off and to adjust the heat if necessary. You could simplify this and reduce cost by just going with an on/off switch. The one I got came with an enclosure and it turned off. There are cheaper and smaller options but they don't all turn off and then you need to craft or buy some enclosure. The one I got is a little larger than I would like. Anyway, I hooked the other end of the coax pigtail to the appropriate points on the controller. I used a standard SAE connector I had to connect to the battery inputs. Then, I used the fused Battery Tender SAE connector to the battery.

I've since ordered a 6 circuit fuse block so I can move all of my connections to the battery to this. Not really keen on removing the tank. Will probably switch the power leads to coax connectors when I do this.

To use it, I put the jacket on, connect the power controller to the jacket and then put the controller in my riding pants pocket. Motorcycle jacket goes on over the heated jacket. Then connect the SAE connector to the one on the bike connected to the battery. Then set the controller to the desired level of heat. I've not ridden in very cold weather yet so I can't tell how well the controller works. Overall, in 40's and 50's. it is very toasty, probably too much when it's warm. I need to drop the quilted liner from my jacket to get a better feel for how well it works.

Anyways, fun, easy project that seems to work and saved some $$$ on a commercial purchase: $62 vs ~$250. You could do it cheaper if you used a jacket you had, didn't need heat control, and already had an open connector on the bike. And like many of my projects, my wife thinks I'm crazy. Been suffering through Una-bomber jokes.

Some photos...

DIY Heated 12v jacket by acurley, on Flickr

DIY Heated 12v jacket by acurley, on Flickr

DIY Heated 12v jacket by acurley, on Flickr

DIY Heated 12v jacket by acurley, on Flickr

DIY Heated 12v jacket by acurley, on Flickr

DIY Heated 12v jacket by acurley, on Flickr

DIY Heated 12v jacket by acurley, on Flickr

Andy

Love it!

Nice work.

Wow. The ultimate vote of confidence in one's own electrical skills. Any electrician with that on his resume gets hired!

Respect.

Why did choose copper instead of nichrome resistance wire?

I went with stranded copper because, according the my deep internet research, was more durable for use in this type of application. Coated wire was recommended to insulate the heat. Several examples used silicon coating.

I wasn't familiar with nichrome before you mentioned it. Looks like it's maybe used with vaping or something? The wire I saw on Amazon had a resistance of 6.5 ohms/ft compared to my 0.1. I don't think that would get very hot at these lengths. Maybe I'm missing something.

racurley wrote:I went with stranded copper because, according the my deep internet research, was more durable for use in this type of application. Coated wire was recommended to insulate the heat. Several examples used silicon coating.

I wasn't familiar with nichrome before you mentioned it. Looks like it's maybe used with vaping or something? The wire I saw on Amazon had a resistance of 6.5 ohms/ft compared to my 0.1. I don't think that would get very hot at these lengths. Maybe I'm missing something.

Niichrome is one type of wire used specifically for resistive heating applications. It is available with high temperature, low thermal resistivity coating to allow for heat transfer. The wire metallurgy and the coating are designed expressly for high temperature conditions.

Conventional copper wire is designed to conduct current with low resistance; the copper (or Cu-alloy) and wire shield are usually not designed to withstand high temperature. The thermal resistance of conventional wire insulation is high, which keeps heat in the wire rather than transfer to surroundings. Too much current via too much voltage = hot wire and potential of melting copper and/or insulation.

I'm not saying that use of small diameter connection wire won't work, just that it's designed for applications that are not supposed to get hot. You can safely heat nichrome or other resistance wire - with less wire length and weight - and not worry about "letting the smoke out". And heat transfer from wire through coating is more efficient.

FANtastic.

I'm impressed! Very very cool!

I take it there is no heat within the sleeves?
I bought my Warm-n-safe jacket liner 10 yrs ago, opted for full liner vs vest to help with keeping arms warm. But I can see where sleeves could create another challenge.

I rode my first R for 4 yrs before buying a jacket liner. My very first thought was .. "Why did i wait so long?"

Congratulations on a brilliant design and execution!!

Thanks. I did put heat in the sleeves. i just turned the jacket inside out and added the wire down the sleeve to probably just past the elbow. It's nice.
I agree with the "why did I wait so long" sentiment.

sweatmark wrote: Niichrome is one type of wire used specifically for resistive heating applications. It is available with high temperature, low thermal resistivity coating to allow for heat transfer. The wire metallurgy and the coating are designed expressly for high temperature conditions....

Sweatmark, I've now found several posts from a guy named Ken Phenix on various boards who has made a lot of heated gear. He uses 26ga nichrome which he covers in 1/16" heat shrink tubing. He does this with 54' inch sections which provide 15.6 watts per loop. A little more brittle than the copper but I think cheaper.

He has several great examples of heated glove liners. He also recommends the Warm'N'Safe heat trollers. Kind of expensive but probably worth it.

I also considered a couple of other options for heating...
- carbon fiber heating tape http://www.carbonheater.us/ which looks interesting.
- carbon fiber heating elements for heated seats replacement. I couldn't find anything that would fit right for a jacket. Maybe a vest.

Maybe I will give this try on another project.

Ok, I take that back. Ken has apparently quit using the nichrome in favor of carbon fiber because he had too many failures with the nichrome breaking. Not sure how he sources or makes the carbon fiber "wires". Looks like it would be effective.

One could use nichrome or carbon fibre but , considering the OP copper solution works, why bother?
Good on ya Andy.

ok as ive walked past the bike every day for the last 2 weeks and only rode it once... I cant stop thinking about this project.

thanks a lot. lol

I agree with Peels, the more I see my garaged Beakster, the more this project intrigues me.

Nice work!