Conformal Coating ?

[AMDgeek]

Where can i get some gonna go with a D.D.* water/pelt cooling system and want to seal it. If you know of a place on the web or some substitutes or if it is safe on a mobo anny info would help.


*(Danger Den)

 

[Colin]

Permatex blue works. You can thin clear Dow silicone with naphtha (lighter fluid) or use my favorite, Aqua Seal with Cotol hardener. Aqua Seal is liquid urethane rubber used to repair neoprene wet suits and waders. With Cotol, it cures in under two hours and is also ideal for gluing neoprene insulation to your motherboard. The fast cure is great. I can take a KT7 series board, do the stage two voltage mod and prep it for pelts in two and one half hours. You can find Aqua Seal at your local fly fishing shop or dive shop.

 

[ken257]

I have had good luck with Dap aquarium sealant, just a good clear silicone thined with mineral spirits and painted on with a brush.

 

[Mord-Sith]

I use to run a conformal coating machine. I turned out about 20 boards a minute. I cant remember the name of the coating we used but we thinned it with a chemical called xylol. I don't think you can buy xylol without a license though. Anyway my tip is to get some of that blacklight dye and put some in your sprayer. That way you can put your board under a blacklight and see if you missed any spots.

 

[AMDgeek]

ken257 (May 10, 2001 01:18 a.m.):
I have had good luck with Dap aquarium sealant, just a good clear silicone thined with mineral spirits and painted on with a brush.

I heard that that worked but was wary of doing it because I thought that it might be corosive and could be hard on the traces

 

[Colin]

I have a hard time believing the acetic acid in household silicon is that corrosive. I have a friend that does custom Mil Spec work and uses Dow Corning clear silicon diluted with naphtha. If you are worried about it, try the Aqua Seal or the Permatex.


One of the key advantages of using improvised the conformal coating solutions is cure time. Applying three coats, and wait 24 to 48 hours between them with a commercial conformal coating is a real PITA, let alone the cost.

 

[ken257]

I have never had any problems with corrosion and I have done many motherboards and slocket adapters this way. With AMD's I even go so far as to paint the entire top of the cpu (not the core) with the mixture. This waterproofs the resistors and bridges on the cpu so that is one less thing to wory about. It also seals your L1 bridge job up.

Clear silicone and mineral spirits has worked 100% for me many times and Collin's sugestions look to be very good ones. And yes the short cure time is a nice bonus plus the fact that this stuff can be purchased in a local hardware store right now....no waiting.

 

[Colin]

I will second painting the ceramic base for the CPU. If you don't do this or use neoprene on the base, you will get some condensation.

 

[AMDgeek]

ken257 (May 10, 2001 07:51 p.m.):
I have never had any problems with corrosion and I have done many motherboards and slocket adapters this way. With AMD's I even go so far as to paint the entire top of the cpu (not the core) with the mixture. This waterproofs the resistors and bridges on the cpu so that is one less thing to wory about. It also seals your L1 bridge job up.

Clear silicone and mineral spirits has worked 100% for me many times and Collin's sugestions look to be very good ones. And yes the short cure time is a nice bonus plus the fact that this stuff can be purchased in a local hardware store right now....no waiting.

good idea ithink ill try it. so i guess ill go with the dow cornig clear silicone or the aqua seal and thin it.
thanks for the geat ideas guys oh and Collin how do you do the volt mod im having a hard time finding a good explanation.

 

[Colin]

Solder wires to Pin 7 and Pin 10 of the IC that controls the voltage to the CPU. Put a 47K trimmer (49 cents at Radio Shack part # 271-283) between each wire and ground. Use a spade lug or loop under a motherboard mounting screw for your ground connection. For convenience I suggest you mount the trimmers on a piece of breadboard and secure it to your motherboard tray with Velcro.

Pin 7 controls the voltage, Pin 10 controls maximum voltage threshold. Turn the trimmers to full resistance boot your PC and start VIA Hardware Monitor. Set the polling interval to 2 seconds and slowly dial up the pin 7 trimmer until the voltage peaks. This should be about 2.1 volts. Then dial up the Pin 10 trimmer until your screen blanks and back it off a tad. Your PC will probably reboot when the screen blanks. Go back into VIA Hardware Monitor and dial the Pin 7 trimmer up to 2.3 volts. You may be able to go higher but I don’t recommend it.

Caution this will stress your cooling. Be careful or your CPU could end up a crispy critter. I also suggest buying a third hand device from Radio Shack to hold a pre-tinned wire to the IC leg while you solder. The magnifying glass on the third had will come in handy too. Get in and out fast so you don’t toast the IC. Lay off the caffeine and if you are of age, have a beer a half hour before soldering to steady your hands.

Be sure to tie your wires down to the board. After doing several boards, I finally screwed one up. The mod went fine but I snagged the wire to Pin 10 on the end of my workbench and ripped the IC pin right off the board.

[img=[URL]http://albums.photopoint.com/j/View?u=1551335&a=11768501&p=42534658[/URL]]

 

[AMDgeek]

cool ill try it and post how it dose thanks for help