Doc's Homemade Heated Vest Page

Ok, some of you asked so, here it is. A description of how I made a heated vest.  Keep in mind, these aren't instructions nor am I recommending that you try this your self. It takes a little bit of knowledge and  a large set of stones to wire yourself up and hook yourself into your bike battery. If you have both (and don't like riding cold), this might just be for you. If you are one of the faint of heart, call Gerbing and hand over $200+ for one of their vests *. Or, if you are really sick, put your bike up for the winter and stop riding.

To begin, I did some hunting on the web to see who else had tried this. (I made sure someone had done this before me. I might be brave but I didn't want to be the first one to try something like this !) 

I found a couple of pages describing what others had done. The pages were filled with math equations, references to Ohm's law, Burke's law, the peter principle and various and sundry other "laws of nature".  I understood them. (4 years of math and physics in college weren't wasted on me. And no, wiseass, that wasn't 4 years math + 4 years physics = 8 years of college. I took 'em together. I only went to college for 5 years, not 8 !) I only took from these pages what I needed to get the job done (after all, you wouldn't want to have any excess knowledge hanging around, would you ?)  If you are interested in the science behind this, you can search as well. For now, I'm assuming you really don't care and there's no reason you should.

Let's hold up for a minute here and talk about what we're going to do. Several people have mentioned my lack of sanity when they've seen my vest and some have make comments about things like a "Short circuit" and variations on that theme. 

The vest doesn't create a "short circuit", i.e. a direct connection between the battery terminals with no or virtually no resistance or  load, but, from a non-scientific standpoint, it might look like that.  You might fear hooking something like this to your bike battery, however, without going into the science of it, I'll just throw out a couple of similar apparent "short circuits" we all use everyday. A light bulb and a toaster. Each of these simply takes a "load" or resistance and places it in line with  an electrical current.  If you were to cut the wires going into the toaster or lamp, and hook them together, then you'd have a short circuit (also a lot of sparks!). So, what is it within the light bulb and toaster itself that prevents a short circuit?  Each converts the electricity into light or heat. (We hope to avoid converting any electricity into light since, by the time we got the wire that hot, we'd be pretty well toasted ourselves!) This process of converting electricity to heat and light takes energy and, if you take enough energy out of the circuit, it no longer is "short". The foregoing is really "science" but it's close enough.

So, we hope to duplicate the creation of a "load" sufficient that enough energy is taken from the circuit that we don't have a short circuit. In our case, the wire itself will be the load, it will heat up and In the process, we hope it will heat up enough that it warms us while we ride. If you review the science of it, 50 feet of telephone wire is about right. If you use less wire, you'll end up with too hot  a wire. If you use a larger grade of wire,  you'll end up with a cooler wire and no heat from your vest.. 

So, with this limited bit of knowledge, I went hunting. Down the cellar I found a roll of telephone wire some nice Bell Tel guy had left in my house years ago.

   Click on the picture for a larger photo. Then use to back arrow at the top left to return to this page.

Now you ask, what is the exact grade wire we need. My exact answer is 'I've no idea". All I can tell you is it is the standard wire found in your telephone connection, the part in the wall, not in the phone itself. Look at the picture and ask at Radio Shack, I'm sure they have it.

I took about 52 feet ( theory said I needed 50 feet. I took a bit more since I could always cut some off) of the wire and connected it to my bike battery and yes, it got nice and toasty. Success ! I left it on for about 15 minutes and when the battery didn't explode and the wire insulation didn't melt, I decided this just might work. So, I took out my Joe Rocket Phoenix Jacket (it's made of mesh), ran the wire in and out of the mesh, hooked it back up and rode away. (It actually was more involved than this but you get the idea.) It worked quite well. I used that under my regular riding jacket for a couple of weeks just to make sure everything was OK. It was bulky as hell but kept me warm. It was time to move on. I felt like Louis Pasteur searching for a cure for polio. ( I know it wasn't Pasteur but Salk  who cured Polio but are you really sure Pasteur didn't look too?  I thought so.)

I have a Condura riding jacket I really like. It has a built in liner and, unless it gets really cold, the jacket and liner keep me warm.  I decided I'd keep the jacket and liner and put a thin heated vest between them. ( When I was using the Phoenix jacket, a couple of the wires rested against my neck and arms. I didn't get burned but it was sort of hot and uncomfortable.) That way the liner would help spread the heat more evenly and keep the hot wires from touching my skin.  I took a trip to my local ACE hardware store and bought a safety vest. 

   Here it is! Cost about $5

This is a good time to talk about why I wanted this type of mesh vest and what I see as the major danger in what we are doing. From above you know you need that 50 feet of wire to create a sufficient load that there isn't a short circuit but...what if, somehow, the length of wire were to reduce in size from 50 feet to, say, 10 feet ? How could that happen you ask ? If I simply ran the wires inside my jacket, allowing them to move around, there's a chance they might rub against each other, wear off the insulation and connect metal to metal. If that happened with 40 feet of wire between the worn insulation parts, the result would be that the electricity would bypass the 40 feet and just 10 feet of wire would be connected to the battery.

Well, I haven't tried it but I'm pretty sure  that 10 feet wouldn't put enough load on the circuit and I'd either have a red hot 10 foot piece of wire on me or,  heat up the battery and cause it to explode (or maybe both). I don't know about you but I consider either of these possibilities to be "big drawbacks"!

I decided to use a mesh vest so I could run the wires in and out of the mesh and keep them in place and away from each other. That way, there is no chance of 2 wires rubbing against each other and shorting out.  Also, and this is hard to explain, I made sure that I ran the wire up one side, over about 1 inch and back down. This way, if 2 pieces of wire did ever happen to rub and short out, the piece in between would only be about 1-2 feet long. That would still leave me 48 feet of wire which, might get hotter but not by too much. Keep this in mind if you wire a vest. Start from one side of the vest and work to the other side going up, over and down. When you end the second side, you will still have to bring one piece of wire back to the beginning to complete the circuit. I did this by keeping the up and down wires at least 2 inches from the bottom of the vest, then running the final wire along the bottom of the vest. I also covered this final wire with duct tape to double insulate it. This final wire is the most dangerous since, if the final wire crosses with any other wire, the result will be a large amount of the 50 feet being bypassed. If this doesn't make sense while you read it, think about how you would run the wire to keep any 2 wires from touching and you'll understand.

With all that in mind, I took the wire and cut it into roughly 10 foot pieces (easier to work with) and started at one side of the vest and ran it in and out of the mesh, up and down,  as described above. When a 10 foot section was completed, I spliced it to the next 10 foot section and kept going and worked my way from the side, across the back and through the other side. I tired to space out the 50 feet so there was 30 feet of wire across my back and 10 feet on each side in the front. Here's a picture of how it looked going in and out of the mesh.

Next, I went to Radio Shack and picked up some plugs that matched the Battery Tender plug already on my bike. You can buy these with or without a fuse. Originally I left the fuse out since there's already one on the Battery Tender line, however, the thought of that 10 foot piece of red hot wire on my back kept popping into mind so, I changed it over to one with a 3 amp fuse. This way, if something does go wrong with the vest, one of the fuses will pop before I get toasted. (I hope!)

  Wire with fuse. Keep it long so you can hook up before you get on the bike.

After using the vest for a while, I found that the mesh makes the vest easy to scrunch (real word? ) up. I didn't really feel it in the jacket but I was concerned about the wires rubbing against each other. After a little experimenting, I found that putting duct tape on the vest gave it the right amount of weight to keep from getting scrunched. Also, I don't know about you but for me, no job is truly complete until I've found a way to use duct tape in it.

   The front of the vest. Click on this pic. I left it large on purpose. Look closely and you can see the wires in the back of the vest. Also, I took some of the duct tape off of one side so you can see the wires in the front.

The back of the vest. Isn't it pretty ?

 I could have made some gloves too but it got cold too quickly this year. I bought a pair of Gerbing gloves (They are great) and redid the connecter of my vest with a splitter. 

Now I connect one plug to the bike and one plug to my gloves and run everything from the one line to my battery. (The gloves have a controller that allows you to regulate the heat, the vest doesn't......yet!)

I've used this vest and setup about 3 months now. I'd guess it's been over 30 hours of use with a couple of 2 hour rides in there. I haven't popped a single fuse so I'm assuming everything is fine. The vest gets what I would describe as very warm. I'm sure it could easily be made a lot hotter by removing the extra 2 feet of wire but, for now, it's working fine, I'm staying warm so I'm going to leave things as they are. I  was thinking of buying a Gerbing vest to go with the gloves but truthfully, this vest is working so well I'm going to wait. Will this vest stand the test of time ? Who knows but for a total cost of about $10, I can easily afford to make one each year or even a couple of times a year.

Hope this answers all the questions people have been asking.  If you have any questions, comments etc. drop me a line at doc@JerseyBiker.com

UPDATE

Ok, the above was written last year (1/2001). I was commuting almost daily but only about 10 miles total. I was doing longer rides on the weekends. So, there was a lot of "on and off" type wear on the vest. After about another month or so the vest started getting kind of hot and I think that there might have been some wear in the wires due to the constant on and off. I never did blow a fuse so, I'm sure things never got too bad. I decided I could pull the vest apart and fix whatever needed fixing or, put on some type of regulator like a variable resistor or, since I liked the Gerbing gloves so much, buy a Gerbing vest. Since I'd been doing a lot more winter riding than I'd thought I would, I opted for the Gerbing vest. The final analysis was that after about 4 months and 50-75 hours of riding with the vest, it was definitely a worthwhile (and cheap) project. However, if you are going to do a lot of winter riding and anticipate doing so for more than 1 year, I suggest you spring for some real heated gear. I happen to like the Gerbing gear. I had the Widder gloves and found the leather much too stiff for riding. The Gerbing gloves are very soft and I might even pay the $100 for them if they weren't heated. I haven't seen or tried the Widder vests so can't comment on them. I ordered a pair of Gerbing pants which should arrive any day.

Good luck and  Ride Safe

DOC