DIY heated undergarments

[Lobzilla]

Has anyone tried heated motorcycle garments or carbon fiber heating pads in a drysuit?

The heated vests from BTS are prohibitively expensive and I saw one leave a nice burn on someone's back where the vest shorted out. I think a DIY solution would be no worse than that

Actually, I can imagine something safer by using a PWM controller that monitors the current draw and cuts-out in case of a current increase due to shorting.

Controller and battery would be in a light canister and connect to the garments/pads through commercially available bulkheads ($$$).

Any thoughts?

 

[rjack321]

Has anyone tried heated motorcycle garments or carbon fiber heating pads in a drysuit?

The heated vests from BTS are prohibitively expensive and I saw one leave a nice burn on someone's back where the vest shorted out. I think a DIY solution would be no worse than that

Actually, I can imagine something safer by using a PWM controller that monitors the current draw and cuts-out in case of a current increase due to shorting.

Controller and battery would be in a light canister and connect to the garments/pads through commercially available bulkheads ($$$).

Any thoughts?

I have used the carbon fiber pads in the past. The problem is not that the current actually goes up, its that it all goes through one area. That's what's causing burns. Can still happen with the carbon fiber although I am not sure exactly how, possibly from a fold. I only had a pencil eraser sized burn once and don't know how it happened as it never repeated.

The BTS vest has no nichrome wires so I'm not sure where that burn came from.

The carbon fiber pads do last alot longer than any wired vest. They are not water proof and for non-deco diving you are better off getting a better undergarment.

I have some and they worked well. Eventually the bulkhead wore out and I haven't replaced it so I haven't used the vest in years. Haven't really needed it since I ditched the 400gm thinsulate for a weezle. A nice 12mm Otter Bay hood is money better spent as well.

If you go this route anyway, you want about 50-100W of heat. Less is pointless, more is actually counterproductive since you will sweat and that moisture will enhance the heat loss in other areas of your suit. ~60W also matches well with a 14Ah SLA battery as a power source. Use a E/O cord and don't have the battery on in salt water with it unplugged.

 

[Lobzilla]

rjack321,

Thanks for your comments and info.

The idea of a heated vest etched itself in my mind during my last dive in 36F water that I had to do with minimal undergarments after I forgot my weight belt at home. While the cold was brutal (DUI cf200 with thin polyprop underwear and a 200g sweater), it was also apparent that thin undergarments and less lead are nicer in terms of mobility and control.

There was a guy at Dutch Springs yesterday that made a 'vest' with two car-seat heater pads and duct-tape shoulder straps. He cut the heater pads to match his battery output. This was possible as the carbon strands are wired in parallel on the pads he used. His heater worked well and certainly got some attention with the distinct getto look.

Hoping to break new ground, I had ordered seat heating pads last week. But at least now I have the assurance that I did not waste $36 on six pads.

Two other somewhat related questions:

I plan to switch all my cans to E/O cords. What would be a good position for the connector if the can is used for a Goodman light?

How can I order an Otter Bay hood? I did a search but their website is broken.

 

[TSandM]

I would recommend against the motorcycle vests, at least the ones we bought. We used them, and they were helpful, but on both of them, the electronic controllers failed, and the ones we bought to replace them failed. It's sad, because I'd really like to be able at least to use them on land, but that was $150 not well spent in the end.