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BrianG · 11.28.2006, 04:21 PM

The heat problem with the Quarks is two-fold really.

1: The case doesn't have enough thermal mass or fins to effectively pull the heat away from the FETs and dissipate it. This is where an added heatsink comes in. Even though the ESC doesn't have a beefy enough heatsink out of the box, at least Quark provided a nice spot to attach one!

2: The construction is a bit wacky, but for a reason. There is an Aluminum slab between the FETs and the case. This slab is held to the case via some type of soft rubbery thermal pad. The same material is use between the FETs and the slab. So there are three layers of material between the FETs and the casing; FETs -> thermal pad -> slab -> thermal pad -> case. So thermal transfer isn't the best right out of the box. The slab is really just a spacer so the caps on the end will sit right.

I'm sure the ESC would run OK like this since that is how it was designed - but after some use and dirt working its way into the case, the adhesive on the thermal pad becomes somewhat unstuck. Of course this drastically affects heat transfer.

What I did was pull the ESC apart (be careful of the SM cap by the button!), and remove the ESC circuit from the case and remove the rubber stuff on both sides of the slab. Because the rubber stuff is fairly thick (about 1/2mm), a new thicker slab needs to be made. The existing one is about 2mm thick so, a 3mm (1/8") thick piece of aluminum works great. Once cut to the right size and polished, and apply thermal epoxy to secure the FETs to the slab, and then epoxy the ESC/slab to the casing. Just be careful not to get the Arctic Silver stuff on the FET leads, unless you use the non conductive version.

Once the epoxy cures, you'll notice a huge difference in the thermal properties of the ESC. It will heat up faster and cool off faster. It will also feel hotter to the touch when running. These are all good things because it means the heat is not staying IN the ESC. Add a heatsink to get rid of that heat and you are golden.

Of course, this almost definitely VOIDS THE WARRANTY, so be advised.

	(#6)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	11.28.2006, 04:21 PM The heat problem with the Quarks is two-fold really. 1: The case doesn't have enough thermal mass or fins to effectively pull the heat away from the FETs and dissipate it. This is where an added heatsink comes in. Even though the ESC doesn't have a beefy enough heatsink out of the box, at least Quark provided a nice spot to attach one! 2: The construction is a bit wacky, but for a reason. There is an Aluminum slab between the FETs and the case. This slab is held to the case via some type of soft rubbery thermal pad. The same material is use between the FETs and the slab. So there are three layers of material between the FETs and the casing; FETs -> thermal pad -> slab -> thermal pad -> case. So thermal transfer isn't the best right out of the box. The slab is really just a spacer so the caps on the end will sit right. I'm sure the ESC would run OK like this since that is how it was designed - but after some use and dirt working its way into the case, the adhesive on the thermal pad becomes somewhat unstuck. Of course this drastically affects heat transfer. What I did was pull the ESC apart (be careful of the SM cap by the button!), and remove the ESC circuit from the case and remove the rubber stuff on both sides of the slab. Because the rubber stuff is fairly thick (about 1/2mm), a new thicker slab needs to be made. The existing one is about 2mm thick so, a 3mm (1/8") thick piece of aluminum works great. Once cut to the right size and polished, and apply thermal epoxy to secure the FETs to the slab, and then epoxy the ESC/slab to the casing. Just be careful not to get the Arctic Silver stuff on the FET leads, unless you use the non conductive version. Once the epoxy cures, you'll notice a huge difference in the thermal properties of the ESC. It will heat up faster and cool off faster. It will also feel hotter to the touch when running. These are all good things because it means the heat is not staying IN the ESC. Add a heatsink to get rid of that heat and you are golden. Of course, this almost definitely VOIDS THE WARRANTY, so be advised.