||[Aug. 3rd, 2002|11:53 am]
The Veritable TechNinja
|||||arts & crafty||]|
|||||Beefcake - Spontaneous Human Combustion 3||]|
Well, I finished the resistor pack. T from my office finally gave the drilled heatsink back at about 10:30 yesterday morning. The "sparkies" that T took the HSF to claimed that there was no reason to use two heatsinks, never mind the fact that I had already bought two. I immediately ran to my car to get out the working board to fit it to. No go, apparently their measurements were off, or the board layout had changed within the last 2 months. I told him about it, he agreed to modify it with me. Long story short, I got it back from him at the very last second. I tore ass to Lansing to pick up P from work (now an hour late), still with no AC. Then, last night, I finally fit the board. So I set up a working space, and got to it. Mixed up the Arctic Alumina in a juice bottle cap, just the right size and eminantly disposable. Surprise, the reaction is immediate and very exothermic. I hurried to slather the board, used the last of the congealing epoxy to make a shock shield for the resistors on the other side, and left it to cure. Surprisingly, that was a quick process. I spliced the fan wires in to the output to the blower motor, taped them up, and I was done. Well, I promised pics, so
Well, it's pretty obvious that the rush to apply the epoxy before it melted the cap or hardened kind of messed up my concentration. The pencil marks on the HSF are to align the resistors in the well once there was epoxy obscuring it.
This will explain how I did the splice. Just snipped off the RPM wire, stripped the power and ground on the fan, and wrapped the wire around the blower motor leads. Ooh! That reminds me, how I stripped the big-ass wires to the blower motor.
The single coolest tool I've ever used. G's wire stripper. It's got the standard two-half-circle blades on one side, and a griper that clamps the wire in place. Then...
You continue squeezing the handle. The half-circles move along the wire as it's held in place by the other end of the tool. It cuts the jacket, then slides it along the wire, sort of bunching it up. This way, you're provided with the minimum amount of exposed wire to splice in to, and all you have to do to tidy up your work is slide the jacket back up the wire. Help, I'm becoming an electrical engineer.
UPDATE: It works. Really, really well. I had my AC running on various speeds for about 30 minutes, the board was only slightly above ambient on the bare side. I'll have to solder the fan wire splices, but that's less than 10 minutes work, and free. Haven't mounted it to the floorpan yet, but I'm not even sure if I need to. I'm going to leave the slit in the blower shroud (where the board used to be) as is, to provide a small vent to keep pressure down. It's likely that increased load on the blower power (and thereby the board as it's in-line before the motor), caused by wear and blockage of the intake, caused it to blow the boards. Yeah, it slightly hinders flow from the vents, but the chilled air is still entering the cabin from the slit.