best thing to use to add water cooling to a speedcontrol

[fas]

looking for the best thing to use when adding water cooling to a speedcontrol I have the plates and want to find out what is the best thermal adhesive to attach it to the fets

Fred

[Alexgar]

3m double sided thermal tape. go to eBay and search thermal tape

[NativePaul]

Thermal tapes and pads are better than nothing and easy to use but are actually terrible at heat transfer compared to thermally conductive glues, for example the best tape that 3m offer is 1.5w/m and the best thermal epoxy I have found is Arctic silver which is 7.5w/m. Personally I have used arctic alumina thermal epoxy which is slightly worse than silver but non conductive so safer around FET legs and still well over twice as good as the best thermal pads (which are hideous prices. I'm sure all OEM pads will be under 2w/m for affordability, I did find some that was significantly better, but it was £40=$60 for enough to do 1 large HV ESC, and when I discovered thermal epoxy it turned out to be significantly better still, and while they are not cheap at around 10-20 per pair if tiny syringes, they would easily have done 2 of the same size ESCs for a quarter of the cost of the best pads. Even if tapes and pads improved till they were as good as adhesive, adhesive would still have a big advantage in practice as with adhesive the high points are in direct contact, whereas if tape or pads are used the high points will always be separated by the thickness of the tape or compressed thickness of the pad.

I now mix my own thermal epoxy, I bought a large quantity of aluminium oxide based thermal paste and mix it 50/50 by weight with regular 30 minute epoxy, I have no figures for its conductivity but it seems to work well, is very cheap and I cant imagine it being nearly as bad as a stock pad. The bond is not as strong as stock epoxy which has its advantages and disadvantages, I suspect that if you bought aluminium oxide powder instead of grease and added it to your epoxy you would get a better bond and better conductivity like the commercial products, but I have not tried it yet and probably have a lifetimes supply of grease so I doubt I will unless I loose my tube.

[TRUCKPULL]

Fred

Here is the best stuff I have ever found.

MG Chemicals
Silicone Heat Transfer Compound

Totally Non conductive

http://www.mgchemicals.com/products/greases-and-lubricants/thermal-greases/silicone-heat-transfer-compound-860/

I bought mine at a Electronics store.

PS- Works even better when applied all the way down from the top of the Fet to the circuit board around the Fet legs.

Larry