Thermal Tape??? - RC-Monster Forums

jhautz · **Thermal Tape??? -** 06.25.2007, 03:42 PM

I want to try and "restick" the fets to the case of the quark, but I dont want to get into thermal epoxy and such. The heatsink on the back of the quark doesnt seem to be working the same magic that it once did. This was the first one that I put a heatsink on and back then it solved the thermal problem with great sucess. However as of late its just not the same. I am running the same truck, with the same overall gearing, and the same motor, and same batteries... but it is definatly overheating much easier now than it did in the past. I used to be able to run this thing all day with this setup and never have to stop because of heat. But... It seems as if its gotten worse over time. So I tryed swapping in a quark from another truck that is only a couple months old and it ran like it was supposed to. All the way through a whole 8000mah pack and didnt have to stop for ESC cool down. So, I'm thinking that the thermal tape/pads on the inside of the older quark are probably starting to come loose from the vibration and such. If I can get this to work like it used to by just replacing the thermal pads Id like to do that rather than getting crazy with all kinds of mods that Ive seen done.

Can anyone tell me how thick the thermal tape they use is? I was looking at this stuff and wondering if it would work for sticking the fets to the heatsink.

http://shop2.outpost.com/product/277...H:MAIN_RSLT_PG

If anyone knows anything about thermal tapes. I really dont want to get into making custom thermal pads and using the permanant thermal epoxy like many have done. If I can just get it back to where it was Id be happy to treat it like a maintenance item. Every season open it up and replace the thermal pads tape. That would be no big deal.

I just dont know what type of thermal tape to use. Anyone have any info or links to something that would work?

03:51 PM

jhautz, check this out...

http://www.rc-monster.com/forum/show...6&postcount=13

BTW, not to get off topic or anything, but what gearing do you run with your 1512 in a truggy?

wallot · 06.25.2007, 03:54 PM

I have chomerics THERMATTACH T412 that I used to attach quark to heatsink, but holding power sucked and had to put few drops of superglue in corners. its very thin but transfers heat vere well

T411 is bit thicker (about the original quark one) but heat transfer is worse than the T412 (but same as the original quark one I would guess)

I just glued my quark

jhautz · 06.25.2007, 03:55 PM

Sweet! Thanks....

I'm just wondering if this would work with the thermal tape i posted. Its only .006in thick. So its very thin stuff

wallot · 06.25.2007, 04:02 PM

just measure the original tape to see if 0.006 is thick enough

BrianG · 06.25.2007, 08:31 PM

Honestly, I wouldn't use tape. Tape requires a very flat mating surface for proper holding power. Besides, the existing stuff is kinda cushy and quite sticky; if that didn't hold, the only thing that will do better is thermal epoxy. Can't forget the kind of shocks and dusty environment these ESCs are subjected to.

If epoxy scares you because it isn't "removeable" - don't worry. Thermal epoxy IS removeable if you freeze the ESC for a little while. The epoxy gets quite brittle and simply breaks. Then, an exacto knife is all is needed to clean the old stuff off.

nativepaul · 06.25.2007, 10:36 PM

Could it be as simple as your heatsink is in need of a clean? A dirty heatsink seriously impedes heat transfer and is bound to happen over time, I'd try giving it a wash before I did any internal mods.

jhautz · 06.25.2007, 10:51 PM

Quote:

Originally Posted by nativepaul

Could it be as simple as your heatsink is in need of a clean? A dirty heatsink seriously impedes heat transfer and is bound to happen over time, I'd try giving it a wash before I did any internal mods.

I wish it were that simple.:002: Sure would be alot less of a PITA. I keep my stuff pretty clean. There isnt a layer of dirt on it or anything. Like I said... I strapped a different quark to the same heatsink and it ran cool. no problems. I think its just the thermal tape starting to go. Its not like it overheats in a minute or two. I just have to stop halfway (15 minutes or so) though the pack and let it rest for 10 minutes or so. Then run the 2nd half of the pack. When it was "right" I could just keep running, and running, and running...

I guess I just gotta bite the bullet and do the epoxy mod. I did order a couple diffferent pieces of thermal tape to try it out, but I also ordered some of the arctic sliver thermal adhesive. Once it all gets here I'll tear it down and make the decision.

BrianG · 06.25.2007, 10:55 PM

Quote:

Originally Posted by jhautz

I guess I just gotta bite the bullet and do the epoxy mod. I did order a couple diffferent pieces of thermal tape to try it out, but I also ordered some of the arctic sliver thermal adhesive. Once it all gets here I'll tear it down and make the decision.

If epoxying directly to the FETs, you should use this stuff instead. The regular AS has traces of silver in a suspension and while it won't short out, it can introduce capacitance to the circuit and cause "weird stuff" to happen. The stuff in my link is totally electrically non-coductive and non-capacitive. Save the regular AS epoxy for metal to metal bonds.

06.25.2007, 10:57 PM

The arctic silver will be fine for epoxying the mod heatsink to the case, but I wouldn't use it to epoxy the sink to the FETs. Arctic silver has silver in it. Although it isn't conductive, it does exhibit some capacitance.

I'd use arctic alumina. No conductivity or capacitance.

06.25.2007, 10:58 PM

Once again...Brian beat me to it.

BrianG · 06.25.2007, 11:04 PM

lol, sorry AAngel. I'll try to give you time to respond first next time. :)

jhautz · 06.25.2007, 11:06 PM

OK guys. Thanks for the tip. That would have really PO'ed me if I epoxied it with the wrong stuff and screwed it up. Its been a faithful ESC so far. It just needs a little attention now.

Just ordered some of the "recommended" stuff too.

BrianG · 06.25.2007, 11:11 PM

I've used the "bad" stuff before and that Quark is still working perfectly fine. You just have to be VERY careful to use a really thin layer so none of it gets squished out the sides and falls on the contacts. Getting some on the drain or source leads probably isn't as big a deal as getting it on the gate lead. WIth the other stuff, you can be a little more liberal, but still keep it thin for best results. Oh, and clamp it good while it's drying for best results.

MetalMan · 06.26.2007, 12:57 AM

I recently got some Arctic Silver or Alumina, and I'm not quite sure which one it is TBH. The packaging was non-factory, and the label was misleading. But anyways, I used it to remount the heatsink on one of my MMs, and I spread it thin just in case it is the Silver and not Aluminum. So far the heatsink has held on just fine, despite the vibration from a rather large fan that's missing 3 blades :eek:. Also, since I did this, the JB Weld on the front endbell of my Feigao 540C 7XL has come undone :eek:.