Arc LS Heatsinks?

Is there a difference between the first run and later LSL, or LSH heatsinks?

How much should I expect to pay for a bare Arc LSL/LSH heatsink? Are there many available due to botched mods?

Thanks!

First run heatsinks are larger diameter, and the really early first runs just had a thick PC board, not an aluminium heatsink. Which do you need, First run, or for the LSL/LSH head? Not sure how many spares are out there, I might have one or two First run heatsinks in the parts bin.

He is looking for a heatsink for an LSH, not First Run.

mahoney said:

First run heatsinks are larger diameter, and the really early first runs just had a thick PC board, not an aluminium heatsink. Which do you need, First run, or for the LSL/LSH head? Not sure how many spares are out there, I might have one or two First run heatsinks in the parts bin.

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Thank you. That is what I needed to know.

Groundhog66 said:

He is looking for a heatsink for an LSH, not First Run.

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Thanks for clarifying that.

ARC LS first run had a two piece head and originally came with three twistie bodies. it's heatsink/board only fits first runs. several style boards were made. two is shown below.

Wayne Y was truly a pioneer and engineered the boards for the world's first production LED light.

ARC LS w/one piece head had many variants, but all used same style board. ARC LS1, LS2, LS3, LSL, LSH, LSH-P, LSL-P, LSH-FP, etc

there were many variants, but here's the three basic board styles.

there's no heatsinks currently available for ARC LS. I've made proto-types on my lathe. but no one has put them into production.
I posted threads on this long ago. sorry don't have links..

part of the problem is ARC's board design is very short. to duplicate OEM stack height almost requires a similar board/heatsink combo.

twistie tailcaps can be easily bored out to accept a slightly thicker heatsink assembly. TSP's spring already allows space.

Cy, that is awesome information! Thank you.

The Arc LS 1st run board that I modded recently had twin circuits on board, running in parallel. The 1st run board pictured below (on the right) only has half of the board populated compared to what I saw. It was also partially potted with epoxy.

The LSL and LSH boards that I have modded were all identical, except for the emitter (pictured below on the left). That is consistent with what you have shared.

I can see the difference in size between the boards. That will be something to look out for.

Thanks again!

Here are a couple of mods I have done with non-Arc boards - there are some other similar examples other folks have done as well. They may give you some ideas on how you want to approach it. As has been mentioned, minimizing stack height is the key. A new Rebel may give you a millimeter or two extra to play with.

http://candlepowerforums.com/vb/showthread.php?p=1586690#post1586690

http://candlepowerforums.com/vb/showthread.php?t=154163

Paul

Paul, those are some really cool mods.

I am actually working on a driver to replace the stock PCB. I enjoy the PCB design, etch and population process, so it is not convenience that I am looking for. I have found that a Seoul LED, Khatod 17mm reflector and a 1mm window are a perfect replacement for the stock components.

Even a straight emitter and reflector swap is a big improvement over the stock Luxeon. Especially if it is one of the early low dome versions.

datiLED said:

Paul, those are some really cool mods.

I am actually working on a driver to replace the stock PCB. I enjoy the PCB design, etch and population process, so it is not convenience that I am looking for. I have found that a Seoul LED, Khatod 17mm reflector and a 1mm window are a perfect replacement for the stock components.

Even a straight emitter and reflector swap is a big improvement over the stock Luxeon. Especially if it is one of the early low dome versions.

Click to expand...

My Arc LSH-H sports a Lux 1 SWOH with LE set to 250mA's to the led. Four hours flat runtime on one CR123 (bounce with lightmeter). Of course today a Seoul would have more more output with essentially same runtime. I do like the lux 1 color.

Bill