EDIT: Decent flat mag heatsink found!

I was searching the world wide web and found these things called “freeze plugs” that people are using to make “solvent traps” out of maglites.

I was looking at the things and they seem like they would make a decent cheap maglite heatsink.

They are typically steel, but for ~$2 and a snug press fit I think they might be good. Anyone familiar with this or have any thoughts?

EDIT: See a better option in post #14

Maglites are typically used for powerful lights, in part because their size allows for good heat sinking. These plugs are cup-shaped, so they lack thermal mass and they’re made of steel which conducts heat rather badly (15W/mK). I wouldn’t use them.

Actually, they are using them for silencers on weapons. All the hype is to try to get away with selling them legally, under a different name and "made for a different purpose". They are not for solvent. The freeze plugs are made for replaceable discs made to be bored for the barrel of the gun and the holes to be drilled in them are for gas ports, to help silence the guns. Once you Google it and see the photos, you will soon see the true use of these things.

Solvent trap cleaning systems. What will they think of next?

I searched some auto websites and found some brass freeze plugs. I don’t see how these could be any worse than lights that use pills. With a good press fit and a little bit of mass, I think they would make great mag heatsinks…

http://www.oreillyauto.com/site/c/detail/DAG0/565104/N0290.oap?ck=Search_N0290*–1*–1&pt=N0290&ppt=C0142
http://www.oreillyauto.com/site/c/detail/DAG0/5651041/N0290.oap?ck=Search_N0290*–1*–1&pt=N0290&ppt=C0142
http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Expansion-Plug-1-378-35-000-mm/\_/R-SEP3819009_0437001507
http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Expansion-Plug-1-350-34-300-mm/\_/R-SEP3819006_0437022513
http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Expansion-Plug-1-375-34-925-mm/\_/R-SEP3819008_0186355171

Some of those are a little big (35mm), but they could be filed and sanded smooth to make good contact with the mag tube. Looks like I may have a project in the works…

bad idea, imo. especially since there are plenty aluminum heatsinks for maglites sold. and they are easy to make if you have a lathe, (not to mention that there are members here that have lathes and can make a good heatsink) i have used their help more than once.
in theory you can flaten a freeze plug, and knock it in, but that would not be easy to remove it if needed.

I have yet to find a heatsink that can accommodate a 20mm star or 26mm star. I want it to screw down as well. I have looked for a while…

I don’t have a lathe. If I did I would make a nice aluminum heatsink.

I have had a few custom heatsinks in the past, but they were never $2. I also like the idea of local stores carrying them instead of waiting for a custom part.

I’m thinking about a mt-g2 26mm noctigon run at about 1.5 –2 amps. I usually don’t build the ~6 amp monsters like most people.

IMO it’s a bad idea. You wont get good heat transfer from the MCPCB to the steel plug (which is only 1/8” thick) to the body.

If you dont want to wait for one of the pre-designed units sold by members here and at CPF then just go hang out at your local machine shop. Instead of calling and asking for a quote take your light, the drawing (a GOOD mechanical drawing) and a 12pk of beer and go down there at about 4:30 on a tuesday and just tell a machinist there (not the phone lady) what you need. If you want it even cheaper source your own stock in the smallest amount over size as possible.

Do it like that and you can probably walk away with a heatsink to your exact specs for about $5 cash. Calling and asking a shop about a quote for a one off piece and you get full retail pricing. Take some initiative and go down there to show them you only need about 8 minutes of work and most likely they’ll be more than happy to help you out.

you do not need any complicated design, just a simple smooth puck, about 1\2in thick will do, than drill\tap holes and use screws to hold led star down. do not forget holes for wires.

member Vesture of Blood used to do lathe work, i had him do some lathe work for me, great job he did. pm him i do not know if he still does it.

cpf memebr h22 sells ready made heatsinks for c and d mag, he is not a member here but you can e mail him, see this link*
his heatsinks are made with posts for certain leds, but i use his sinks’ back side, i just turn them upside down they are smooth and flat on the back side. however a heatsink for c mag has a rim and you can not turn them upside down.

search this forum too, i’m sure “who can make a heatsink” question poped out here before.

I’m not calling you out cause I havent used an H22A heatsink for a long time but when I was using them there was a lip on the top to hold it from dropping all the way down in the body so it couldn’t have been flipped over.
Again not implying you’re wrong, he could of made changed to how they’re made, but the last one I used couldnt have been flipped over…

BTW Matt (VestureofBlood) is still doing lathe work for us here.

yea you used C mag heatsink, they do have a lip, and i mentioned it in post 10. d heatsinks have no rim.

I have3 of the H22A heatsinks for d mags, all of them have a lip

At 1-2A even with an MT-G2 just about any solid chunk of metal 1/8”–1/4” thick and press fit into the Mag head would do the trick. Brass, aluminum, steel, or copper, whatever you can get in there and stick a copper DTP star to will do the job. Don’t sweat it unless you’re looking for 20W instead of 10W.

after reading this i went and actually opened up D maglite i had build a while ago using h22 heatsink, and both of you are correct, D also have a lip, that i forgot about, since i used h22 sinks a while ago, i had to cut it off using dremel cut off wheel, while the C sink was not nearly as simple to cut off. it was someone elses heatsink that had no lip, and could be simply flipped over, that i bought on cpf.

I finally found a flatop heatsink! There is not a ton of mass to the things, but they are adequate. It’s a guy that makes his own aluminum freeze plugs and sells them on ebay
http://www.ebay.com/sch/danieltmedlin1963/m.html?\_nkw=&\_armrs=1&\_ipg=&\_from=

They are not terribly tight, but I was able to add a piece of aluminum can wrap to snug things up. Hope this helps someone!

Actually if you spend a little bit more you can get decent heatsinks designed for various reflectors and LEDs.

For $28 you get 3 aluminium heatsinks with good heat transfer, 14mm flat top and flat bottom. That’s $9 each.

Link*

I have been searching for a good heatsink for a while now…

I have used the h22a ones plenty of times before, but they are

  1. primarily meant for 14mm boards
  2. you cant necessarily screw a star down (only glue/epoxy)

Of course you can flip the h22a sinks over and use the back side like some have suggested already in this thread, but…

  1. that requires a good deal of grinding as the lip must be removed
  2. you then need to drill holes all the way through which is not an easy task to do for such a thick piece of aluminum, especially if you do not have a drill press. The one I found were easily drilled with a hand drill.
  3. still more expensive and not really any better than what I found.

I have also had custom heatsinks made before…

  1. they are a bit more expensive
  2. they were not very good quality (the holes were not very straight)

Bottom line these are the best heatsinks I have found that can be easily customized to fit a variety of stars and reflectors. If you could point me to or provide a link for a “decent heatsinks designed for various reflectors and LEDs” I would be thrilled! This is the best I have found to date and thought I would share.