WTB: Small copper stock. 1"x13-14mm

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mattlward
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WTB: Small copper stock. 1"x13-14mm

Someone planted a seed in my little brain for a mod that I am thinking about for the OL Challenge in the mod category. But, I need a copper spacer that is 1” diameter by about 14mm. If you are in the US and have it to spare… please let me know.

TIR based M21B with the FC40!

Thanks Matt

EDC rotation:
KR4, SST-20 FA3 4000k (favorite!)
FW3A, Nichia 4000k sw40 r9080 (second favorite)
FW1A, LH351D 3500k (third favorite)
FW1A, XP-L Hi 3A
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
Emisar D4V2, brass E21A 3500k (night light of choice)

Tumbleweed48
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Do you know any plumbers? They always have scrap bits of copper tubing kicking around. They’d probably give you a couple of inches of 3/4” tubing that you could hammer flat and cut/file into shape.

mattlward
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I would need to make a spacer to raise the mcpcb, think quad spacer. Want to make the pill out of copper for heat transfer. Needs to be about 13mm tall. No lathe so will have to form and fit by hand.

My thoughts…
https://budgetlightforum.com/comment/1807600#comment-1807600

EDC rotation:
KR4, SST-20 FA3 4000k (favorite!)
FW3A, Nichia 4000k sw40 r9080 (second favorite)
FW1A, LH351D 3500k (third favorite)
FW1A, XP-L Hi 3A
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
Emisar D4V2, brass E21A 3500k (night light of choice)

MtnDon
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Sidney Stratton
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1" diameter x 4" long ~ $40 (w/ shipping) [25mm x 100mm copper rod(link is external)]

Ouch!

thefreeman
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I would suggest to use aluminium, much easier to work with (softer) and also much cheaper, thermal conductivity is half of copper which is still excellent, with a big pill there won’t be any difference. Unless you plan to solder on it of course.

mattlward
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thefreeman wrote:
I would suggest to use aluminium, much easier to work with (softer) and also much cheaper, thermal conductivity is half of copper which is still excellent, with a big pill there won’t be any difference. Unless you plan to solder on it of course.

I had hoped to solder the mcpcb to it.

EDC rotation:
KR4, SST-20 FA3 4000k (favorite!)
FW3A, Nichia 4000k sw40 r9080 (second favorite)
FW1A, LH351D 3500k (third favorite)
FW1A, XP-L Hi 3A
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
Emisar D4V2, brass E21A 3500k (night light of choice)

MtnDon
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mattlward wrote:

I had hoped to solder the mcpcb to it.

I wondered about that. Soldering is one good reason to use copper. Though in recent years I have been using thermal conductive tape for mounting MCPCB’s.

EDIT: I have NOT used that product. I only linked to it as an example.

mattlward
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MtnDon wrote:
mattlward wrote:

I had hoped to solder the mcpcb to it.

I wondered about that. Soldering is one good reason to use copper. Though in recent years I have been using thermal conductive tape for mounting MCPCB’s.

Have never even looked at the stuff… good results? What product are you using? I will either need to D&T the spacer, solder to it or otherwise stick the mcpcb in place.

In most of my mods that involve spacers, I have always felt best about direct solder since most of them are hot rods to begin with. I am going to check this weekend when I get time, but I think I have a 1” rod that is bronze, it is kind of zebra striped and has not been polished. It would work but may be hard. The color indicates a higher copper density, does not appear to be brass. Dad had it around years ago to press bearings into blind holes.

EDC rotation:
KR4, SST-20 FA3 4000k (favorite!)
FW3A, Nichia 4000k sw40 r9080 (second favorite)
FW1A, LH351D 3500k (third favorite)
FW1A, XP-L Hi 3A
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
Emisar D4V2, brass E21A 3500k (night light of choice)

Sidney Stratton
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I don’t mean to be apprehensive, but I don’t think thermal tape is a contender to soldering. From the link, 1.5 W/mK is no where close to copper to copper (413 W/mK) or to aluminium (237 W/mK). The giveaway is where they state it performs better with thermal paste – so the tape wouldn’t stick anymore. Better to use paste then? Arctic MX-5 is the most popular but doesn’t have thermal transfer info from Amazon (link )

As soldering can get messy with repeated trial and error set-ups, paste would be a better (albeit also dirty) choice. Then also aluminium would suffice.

MtnDon
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Quote:
What product are you using?

It does not have a name on it. I picked it up at an electronics shop a couple of years ago. I first saw it on Cutter elecronics site. They sold precut star shapes. I tried a few and thought they were great. So I bought a roll that will last me 2 lifetimes. I have also found it useful for a few other things as long as the surfaces are smooth. Easier to remove a star that is taped than if it is soldered or epoxied. None have ever fallen off. My roll is 20mm wide though I recall they had other narrower and wider rolls.

MtnDon
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OK. I posted the link only because I bought mine from a small nearby shop that has no website. Posted that as being “of the type”. I did not read the text. There is no way one can use this tape I have along with paste. The paste will prevent the sticky part of the tape from adhering.

I will also clarify that I do not build super hot rod lights generally but have used the tape I have on a hundred feet or so of strip led’s with no failures. I have used it on a number of mods and builds that pass 3 to 5 amps to the led’s. I don’t usually run turbo very long. I use it where the mcpcb is not going to be held in place by other components or screws. For a typical light with a lens, reflector/optic where the lights bezel or head is screwed on I use paste.

flightless22
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You could cut a copper sheet and copper plumbing pipe to size and fill with copper chop/shot à la the Old Lumens method.

Correllux
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Couple other ideas. I see on Amazon a seller with 1”×12” for $47…might message them to see if they have offcuts or smaller pieces they could sell (seller was “stone” something).

Might look around at old copper CPU heat sinks if you can find and score one cheap. The ones I’ve seen (around Intel 5th gen chips) were close to an inch thick of solid copper and then all the top fins over that. At work we just chunked one into recycling not long ago or I’d have mailed that to you for free.

If it’s worth the effort, you can use different diameters of plumbing pipe and slit those lengthwise, nip them into sections…squeeze a little and drive it into its mate, then continue successively smaller, maybe a piece of copper ground rod for a core, then fill the voids with solder. Copper pipe is nominal…I think 3/4” is right at 7/8” OD, so maybe a coupling would bring it to an inch without having to buy expensive 1”-too-big pipe. ID varies by type (M, L, K in order of wall thickness). Maybe a few nipples and a fitting would be cheap enough to cobble together.

Also thought about wrapping a core rod with a lot of 10ga copper building wire (THHN or such), then that could be pounded a bit and filled with solder. After all that work the $47 for rod stock may look attractive, though.

Actually, thinking just now, could just stacking and soldering a bunch of mcpcb’s be an option? Guess the top layer would need to be sanded off…and then there’s the 1” OD thing.

If you have access to a decent shop press (not the 12-ton cheapies) I’ll bet you could mash the crap out of some ground rod into a nice puck.