PES2 Heatsink compatible with SSC P4?

I tried posting this question on the thread for the heatsink but haven't seen any answers. I'm hoping someone can chime in here.

I've seen some threads that indicate that this heatsink should work with the SSC, and others that say the depressions are designed for Luxeon, and are too small.

I'm looking at getting one from the Sandwich Shoppe, so I would like to find out before I order if it will work?

If I need to fill in the depressions, will the copper spacers that Sandwich Shoppe has for the P4 work?

I would like to use this heatsink so I can use 20mm reflectors, otherwise I would probably just go with the Multisink.

I know Nereus sanded one flat, but I would like to keep it relatively intact. I'm willing to entertain any suggestions.. Thanks!

Do you already have the P4's?

Nope not yet, I'm just trying to build a parts list. I know the Cree is probably the "better" LED, but after my experience with soldering them, I think I'll stick with the SSC's.

I would try to pick up some P4 stars from CPF member PhotonFanatic and a PTS sink from the shoppe. If you need one for a "C" maglite they have some in stock. I have one and the McR20's work fine.

Otherwise, even if the P4 emitter fit the perfect emitter sink, you would have to isolate each slug on the P4 to use them. For me, its easier to get the star based sink from the shoppe and not have to fool with that.

Good luck,
Chris
.308

Isn't a PTS just for a triple setup though? I was going for a Quad mod. Isolating I don't think would be too difficult, I would put a thin layer of Artic Alumina on the bottom first and let it dry, to isolate the slug.

The depressions are indeed a bit too small to fit the P4. However, you can sneak them in inbetween the depressions reasonably well. When I did it one of the P4s ended up with about 1/3 of its slug over one of the depressions IIRC so they don't all have perfect contact with the heatsink. I haven't had any trouble with it yet (I use it lightly though).

I used the method you mentioned to isolate the slug as well and it seems to have worked just fine.

edit: To make clear, I didn't fill the depressions with anything. Other than the excess epoxy that is.

You can always offset the Seoul P4 emitters a bit and do away with the holes all together. So, if you offset each emitter by 45 degrees, they will sit on a nice flat spot. You can use a pencil or a fine sharpie marker and draw lines and dots as needed to indicate where each emitter goes. It is a bit tricky in comparison, but completely doable if you have a ruler and a few drawing instruments.

It may be best to not place the wider based slugs of the Seoul P4 over the smaller holes for the luxeon since you will probably get worse heat transfer. You do not want to have a thick layer of epoxy between the slug and the heatsink. Sure, a fraction of the slug will make contact with the heatsink, but I worry that you will get poor results.

If you offset the LED, I see how you may be concerned with those 4 notches for the reflectors may not line up (on the outer rim/lip). I though that the heatsink was designed to use the McR-20 size reflectors. The IMS reflectors could possibly fit on the heatsink with offset emitters without interfering with that lip. I am not sure about that. If your reflectors do interfere, then you could pull out a metal file or a dremel tool and re-cut the notches.

I see how offsetting the emitters may or may not work. However, I am not sure if those spacers will work to fill in the hole. I have some at home (I am between classes right now), so I can measure the diameter of those copper disks/spacers for you later. From memory, I believe that they are wider than the slugs of both the Luxeon and Seoul P4, so they may definitely be larger than those holes in the heatsink. I will get back with you. I also did a quad Seoul mod, using the older, thinner PQD heatsink last year. I will take a look and see how I did that, too.

-Tony

Well I'm not above getting the dremel out, and shaping the copper discs down to fill the holes. I was also thinking about getting a milling bit to widen the holes, but I'm not sure exactly what kind of bit to get, though I do have drill press.

Even if I did use the offset method looks like I would probably want to fill the one hole that overlaps with a copper disc to get some decent heat transfer.

I guess the other option is to completely flatten the heatsink like Nereus did.

I am interested in what you find Gryloc, so I'll wait for your information with baited breath..

Thanks all to have responded!

wildstar87,

Sorry for the slow response. Okay, the little copper spacer disks measure about 6.90mm in diameter. They are also scrap from copper hole punchings, so the disks are not completely flat (no problem, just hammer each one flat and file each side). Well, the protruding Lumileds slug from a recently purchased Luxeon III had a slug with a diameter of 5.20mm, and the Seoul P4 has a slug with a diameter of 6.10mm. The Seoul P4 slug is slightly larger. It was harder to measure the diameter of the protruding slug on the Seoul P4 since the edge was less defines and the calipers slipped on me. I used a cheap chinese set of digital calipers for measurements. It is not a Mitutoyo by all means, but it is relatively accurate according to some previous measurements taken.

I have the older PQS heatsink, and I ended up offsetting the emitters. I originally used the Luxeon III in the little slots, then when I upgraded it to Seoul P4s last year, I had similar problems as yours. This heatsink does not have a raised rim, and it only has four holes, so it works to offset them.

Now, I checked out the PES2 heatsink in more detail. It was something that I planned on getting recently for another quad emitter mod. I believe that you are correct about the spacing! Check this out for a top view of the PES2 heatsink:
http://candlepowerforums.com/vb/showthread.php?t=122625
I have the older, thinner PQS from modamag for my quad emitter Mag mod, and I believe that he used similar measurements for the spacing between each depression. I measured my older heatsink, then guessed how his would be designed and used my friend SolidWorks to draw it up. I did not include any of the multiple through holes that are drilled in the actual PES2 heatsinks. I have a feeling that those holes will cause a bit of trouble with offsetting. The below picture shows what would happen if you would happen to offset the Seoul P4 emitters. The drawing shows my measurements for the Seoul P4 slugs (solid circles), and the measurements for the round slots from the older PQS (slightly larger than the Luxeon slug).

(click on image for a detailed and dimensioned drawing)

Modamag, I can remove this image if you are uncomfortable with it. Sorry if I did not asf for your permission. It can also be removed if too big (sorry). These dimensions used are from what I measured and observed, and are probably not exact enough for a copied product design anyways. The above idea is Modamag's creative design that is not to be copied and sold! I just want to be safe .

Anyway, you will see that a 45 degree offset could work, but the slug will be overhanging a bit. I tried other angles, but those "tri" slots cause problems every time. I conclude that for these particular heatsinks, offsetting the emitters may cause you trouble.



I suppose you could use an end mill with your drill press and widen those round slots. There is a chance that the mill will make the slots deeper, so the Seoul P4 slug may not reach the bottom, unless you make the round slot 8mm in diameter so the entire emitter will fit in there and you will be trouble free.

The drill press is built to be kind of sloppy with tolerances, so an end mill may chatter a bit (I am used to a sloppy POS drill press, YMMV ). As long as you dive very slowly, you should be fine, though. Just cut a little material away, bring it back up, check your progress, then dive some more. I know that McMaster has some cheaper end mills that you could use. You are dealing with soft copper, so I doubt you would need a nice carbide bit with a fancy coating. I found some cheap end mills for $8 to $13 each. I found a four-flute mill (for a finer finish) for $11.42. It is also a cobalt bit (a plus) so you can use it for other tasks. The place has fast and cheap shipping (especially if you live a few states away from Ohio). A 5/16" bit would work good for you I believe. The diameter of the Seoul P4 is 8mm, and the 5/16" bit is 7.94mm. With a little chattering or vibration, the round slot may end up at the right size or slightly larger. The next sized bit, a 3/8" bit, may be too big (9.53mm), so you would have to center each emitter by eyeball.

When using the end mill, I guess that you have to securely clamp the heatsink in place, then line everything up my eyeball. You could toss the emitters in the finished slots (with no epoxy) then place the reflectors on the emitters to make sure everything is lined up. You may have to go back and remove more material from the sides, but I bet that things will line up easily, regardless of skill level (you have a drill press in the first place).

What do you think? I feel that if you invested in nice copper PES2 heatsink (I am jealous), might as well spend a little more for a perfect fitting slots for the emitters. It seems like the least amount of work for the best appearance and performance. If you need help with the bit selection, PM me. I can give you the part # for the bit.

Finally, you will have problems with isolation of the emitters' slugs if you just slap epoxy under each emitter and apply pressure. We know that the slug of the Seoul P4 acts as a positive contact (an emergency contact when you break off the positive lead by accident), so if the slug happens to press against a high spot on the heatsink through the epoxy, you will get a short there. You will end up with shorted or failed emitters, or generally strange electrical behavior of the light. You may blow you Fatman or Shark driver, too. Well, I seen this post by NYLYTE a while back and I have used his method ever since. Here is the link:
https://www.candlepowerforums.com/threads/157064
With a LDPE deli container lid, and an extra hour to wait, you can have a well isolated emitter that still has good thermal contact with the heatsink. It worked for me on every Seoul P4 I used (and the same with Luxeons). If you can find a way to apply continuous pressure on the emitter as the initial layer of thermal epoxy cures, then you will end up with an even thinner layer. It is probably best to make sure both surfaces (emitter slug and heatsink) has a nice finish. I like to file the bottoms of my emitters.

BTW, what reflectors do you plan on using? I am just curious.

-Tony

Hi Gryloc...

Wow! Thanks for all the great info! As far as the reflectors are concerned, I'm not sure yet. I was originally just going for the IMS20, but I saw on Nereus's mod thread that he had to grind the back down a bit to get them to focus properly. So now I'm thinking the Khatod 20mm that Photonfanatic is selling. Though I was playing with the idea of using the optic instead, but I don't think that would be any better than using a 17mm IMS or Khatod and going with a Download's Multisink.

I'm really hoping that Modamag has some of the PES2 Copper heatsinks left, and that he would be willing to mill the holes for me, like he might have done (he said he would) for one guy back in July '07 I think?

Otherwise I'll have to buy the standard alloy one from Sandwich Shoppe, and either do the end mill on drill press, or try the copper discs.

I'm really leaning towards the PES2, but if it doesn't look manageable, then I'll probably go to the Multisink and 17mm reflectors, or optic, depending on what will give me better throw, because I know it's already gonna be plenty floody.

wildstar87,

Just really quick, I do not know if you would be happy with the Khatod reflectors. I just got some from PF a while back to see how they compared to the IMS 20mm reflectors that I have been using. They are nice quality reflectors, but when I held them up to my quad Seoul light, the beam was much more diffused. When comparing the 20mm Khatod reflectors and the 20mm IMS reflectors, you will notice how "soft" the beam is from the Khatod reflectors compared to the IMS reflectors, which has a very nice, bright, and defined spot. Grinding the back of the IMS SO20XA is easy to do with a file or sandpaper, and yields nice results. The beam is very nice with the 20mm IMS reflector! The IMS SO17XA has a broader, but still more defined beam compared to the Khatod, and I can imagine the optic is even more floody. I do not want to tell you what to get, but I would recommend those 20mm IMS reflectors. It is totally worth the 20 minutes of easy work to take a few thousandths off of the back to properly focus. The beam is still pretty decent even if you do not grind them down. I ended up waiting a week or two before I ground mine down.

All of these smaller reflectors will give you a "floody" beam in comparison to your single emitter lights using bigger reflectors. The IMS has a good, tight hot spot, but you can consider it floody only because of the very bright corona (due to the nature of the Seoul). My next mod, which uses the PES2 heatsink, would be 4 Luxeon TFFC K2s (0200-binned) behind 4 of the 20mm IMS reflectors. The beam of the IMS is even brighter and more defined with a Lumileds emitter! I cannot wait. Thanks for opening my eyes to that PES2 heatsink!

Sorry if it sounds like I am pressuring you. I do not know your preferences in beam type (soft versus tight). I would just hate to see someone displeased. If all else fails (and in the spirit of the CPF), get both. Both reflectors are cheap. You can get the IMS reflectors from Future Electronics for cheap (get 20mm and 17mm). You cannot go wrong.

Well, good luck with the search for the right heatsink. If the seller can mill the notches out for the Seoul, then that is even better! I am sure everything should fit up well for you.

It is very late (or early) for me here in Ohio. I think it may have shown in this post . I worried that I said "20mm IMS" way too much...


-Tony

Oh no I appreciate the observations and advice! Sounds like I'll give the IMS20 a shot after all then, because I do want as much throw as possible, since they light will be inherently floody anyway.

You just had to mention the Luxeon K2 TFFC didn't you... Do you think they are actually brighter in that kind of configuration then the SSC P4? :thinking: I hadn't heard that the K2 was better than the SSC, but I know the TFFC version just came out recently. Of course even if they are better, getting a hold of them could be problematic due to the recall..

Though I'm ASSUMING that they wouldn't have any of the mounting issues on the heatsink, since it was designed with the Luxeon in mind, unless the K2 has a different footprint..

Adding onto this... After doing a little research, the K2 TFFC would be even harder to use on this heatsink, it's definitely not the same footprint, since it's square.. heh..