DIY Cool Shirt (Page 8 of 8)

Picked this pro-tip up on the other forum, and after reading it seems so intuitive but I hadn't thought of it- wear the cool shirt inside-out to put the tubes directly against your skin.

I just buy the cheapest bilge pump that Walmart has on the shelf. 

I think it's this one http://www.walmart.com/ip/Shoreline-Bil … ethod=p13n

Note that if it's been sitting a while, it sometimes needs a whack to wake up from it's slumber (which speaks volumes about how much trust you should put in one of these if you bolt it into your unattended boat).  Kinda annoying if you have to thrash around unstrapping it during the first driver change when the weather is heating up so you can whack the pump.

Seem to recall the tubing is 1/4".  I bought my shirt from Ultrachiller and also bought the female fittings for the cooler from them at the same time.  If I did it over again, I'd probably go with the fitting Van recommends.  If people make their own shirts (I've used both store bought and homemade, both work fine), use male fittings on the shirt and female on the cooler box to be compatible with the commercial ones.  Or go the Spank route and just use barb fittings and pull them apart to disconnect.

If there was one area I'd like to improve on the DIY cool shirt setup front, it would be securing the cooler.  I've got one with 2 ratcheting straps and another with 3.  The straps hold the entire enchilada down and then metal welded to the floor to keep the cooler positioned.  I know how violent flips can be and don't want the driver to survive the crash but not the cooler pummeling him.  It would be nice to have some sort of positive cooler hold-down with something a bit more convenient than 3 ratchet straps to secure the lid for ice replacement/replenishment.  Maybe something quick release pin-ish.  Most anything I can think of involves compromising the water tightness and joining the group of people getting an erroneous BF for leaking fuel.

You don't want that pump.  Outlet is 3/4".  Find one with a 3/8" outlet.  Also, a bigger pump = less ice in your cooler.

I was trying to do something similar on the first cooler I made.  I actually installed latches on the lid to keep the water in and envisioned a hinged, square aluminum tube across the top.  People were continually forcing the latches causing the positive locks to spring out and get lost.
Going with a single ratchet strap rated at 2,000 Lbs was just so much easier

I realized something that is probably decreasing everyones ice chest cold time.  The submersible pump is dumping its motor heat into the ice chest.  I'm not sure how much heat that actually is but i'm sure an external pump that doesnt use the water also as a coolant for the motor would help cold time. Not sure if that is .1% or 25%.  I doubt the little motors in these pumps are very efficient.  You could run one in a gallon of water and monitor temp change and figure it out.

  I realize an external pump adds complexity but it may be worth it. A self priming pump with a strainer would probably do well up and out of the top of the chest.  Mounted low, it would just need a bit to prime.

I still have the peltier stuff but still havent had time to test it.

No problem at all, and got to use an old fuel pump that was just sitting.

We used to fill gallon milk jugs with water, and freeze those.    We would just pop them into the cooler, jug & all.    That way you also don't have to drain any water during the day.

We actually brought a chest freezer to the track, for the 1 super-hot race that we ran in.

Fuel pumps are typically cooled by the fuel going through them.

It think you forgot the watts to btu conversion. 33 watts = ~112 btu. So ~3/4 of a pound an hour, I think. It's been a long week..
Edit, never mind, looks like you just left math out.