That would run and leak into the light for my application. I need something that hardens enough to not run, but still be removable.
I use that paste you linked to sometimes, but only when I have too. It is is very hard to completely clean the residue off just about anything and it interferes with soldering. It may appear to be cleaned off, but has real staying power.
Thought you might be interested in this, I modded a Convoy S6 for a fellow BLFr the other day. Decided to stack chips on the spring side and pot them with Arctic Alumina to protect against a possible short. After everything was said and done, the light only worked in Hi mode. Frustrated, with no other drivers on hand, I managed to peel the AA off the stacked chips, remove the chips, find the problem (the SinkPAD was shorting thermal pad to neg pad, invisibly…can’t find it but it’s there whether an emitter is mounted or not) and restacked chips to complete the build. Didn’t pot again. lol But the point is, it wasn’t extremely difficult to peel the Arctic Alumina off the stacked chips without doing damage.
This was some 1 1/2-2 hours after it was done. I have no idea if it would still come off clean after using the light for a while.
I agree that AA it can be cleaned off. I've done it myself many times and alcohol helps. Just exploring for a better, more budget solution.
I picked up some Permatex Blue RTV silicone as it was $2 less than Ultra Grey and the only noticeable difference I saw on the packaging for Ultra grey was that it was rated for "high torque". The blue still says "sensor safe". So this is ok to use right? Is it better than Plasti-Dip? About the same?
Pics:
-Garry
Cool Garry. Do you plan to mix it with Silicon Carbide?
I picked up a tube of GE Silicone II, but I haven't done a pot yet. I hope to this weekend. What I don't use for potting drivers, I will use around the house.
Please keep us posted. Do you have thread in progress that you will be using this stuff in?
Just my Lawnmower mod thread (Best Way to Run an XM-L from 12v Automotive Source).
Should I be considering silicon carbide? Is it worth it?
-Garry
Only if you need the potting to help remove heat. I've tried to read that thread a couple times, but the electronics stuff was just too far over my head. Sounds like you are doing more installation stuff now. I will have to go check it out.
BTW - that Blue RTV was only $3.97 at my local Walmart. I'm looking at this 400-grit silicon carbide. No idea what grit to buy. Only $6.54 with shipping for 1/2lb.
-Garry
I definitely need to remove heat! That's what's stopped me from proceeding. I'm working on getting the backs of my modules mounted to an aluminum bar which will then mount to the mower frame.
OR is it just better to use the Home Depot Super Lube heatsink compound? I'm guessing that compound doesn't harden though and could make a mess.
-Garry
Huh? What you talkin' 'bout Willis? Who's talkin' 'bout reflectors shorting??? You posting in the wrong thread? Not had your morning coffee yet? :)
-Garry
I bought a half pound from that same vendor. It arrived in very fast. Like a couple days. I think I ordered Sat and got it Tuesday.
400 grit sounds good to me, but this is all new to me. I got 120/220 and 1500. The 1500 looks way too fine. I hesitant to use the 1500 because I have a beard and can really get a good seal with a mask..
Don't use that HD heat sink compound. It's messy and leaves a very hard to remove residue. You don't see the residue, but it really interferes with soldering. I only use that stuff when I absolutely have to. When I do, I use as little as possible.
Sorry, please disregard. That’s exactly what I did and exactly why! Geesh! Getting old…
Garry, I haven’t used any of the Permatex RTV products for flashlights but I have used just about all of them over the years on motorcycles, automobiles, and tractors. The blue is my least favorite, it still smells like vinegar and doesn’t seem to ever dry 100%. I see that the box now says “new low odor formulation” so maybe they’ve changed things since I’ve used it last. My favorites are the Ultra-Grey, Red High-temp, and Ultra-Copper. The Ultra-Copper is supposed to be the highest temperature rated; if I remember correctly it doesn’t really contain copper and is non-conductive.
I don’t know how well it conducts heat, but for general use the GE Silicone II All-weather rated is awesome stuff. It dries smooth, sticks well, and stays pliable year after year in –10 F to 110 F weather. I can’t remember if it has the acetic acid/vinegar smell or not.
Thanks for the info RMM!
-Garry
This stuff should work okay. It's used for sealing ducts and electrical.
It's sticky, moldable, doesn't dry out, non-toxic, less than $3 a pound. It's also really good for catching pellets from an air gun.
If you try to find it, it's not in the hvac section, it's in the electrical section where the wire connectors are.
Hmm, does it work for pulling heat away?
-Garry
It should. It doesn't seem to have air in it.
Air is a great way to remove heat, just make sure it is moving. Thermal conductivity of compounds and all is great, but after the sink is full, it has to be “drained” Automobiles, motorcycles, computers use moving air. So far, flashlights have not utilized moving air.
BTW, here is an article comparing thermal compounds. Almost anything will work, some better than others of course. The MOST important thing is that something is used rather than nothing. Check out this chart carefully, I think it is rather humorous and sobering as to how well crazy compounds like mustard, creamcheese and toothpaste work. Heck, mustard works as well as Thermaltake TG-1
http://www.hardwaresecrets.com/article/Thermal-Compound-Roundup-January-2012/1468/5
The local bars here seem to do an excellent job of getting drivers potted… :party: