I saw those ones and the Sanyos at FT. The only shipping available for batteries is HK surface…45-60 days.
I can order from IS for reasonable shipping and fast delivery. I want some more measurements before I order the cells.
This is my battery carrier.
Here is an 18650 beside an 18500.
The aluminum spacers are 4mm (5/32) in diameter.
And 72mm long
I figure if I shorten it by 15mm, I should be good. (Guesstimate)
I did find an RC place with 5/32 brass tube. It's not close (traffic wise) but I might go check it out. I would just have them mail it, but they have a large selection of small screws, and maybe someone can help me out. I don't know anything about tapping threads.
If anyone knows where I can get some metal rods already tapped with screws...57mm long, let me know.
why don’t you use threaded rod and nuts, instead of the inner threaded rod? you can find it 4mm and thinner, and its way easier. you can put shrinking tube around it to hide the threads. And it’s easier to find too
I was thinking of some standoffs like these 60mm Female-to-Female ones: http://www.ebay.com/itm/20d3454b83 You can just grind down the length a millimeter or so at each end. The flats should measure 5mm across, so somewhat larger than what you have now. What are the dimensions of the screws & screwholes? They are likely to be either M2.5 or M3.
Heheheh.
totilde makes a good point. threaded rod can be used in that way. To keep the low profile you’ll have to use loctite and single thin nuts.
Community effort…haha…we just want to see that beast run!
If you need something that you can solder then you can use auto brake pipe for diy repairs. They are available in copper and are relatively thin... Might not have the space in this light though.
But what an heat sink! Awesome job. Simply awesome.
Using copper tubing for automotive hydraulic brakes is highly illegal at least in the U.S., dunno about Canadia. Copper has very poor fatigue characteristics and cannot tolerate the vibration & flexing in an automotive environment.
I do know copper is regularly used in other parts of the world but I would only use it if I had a death wish.
edit- short version: Ask for 'brake line/brake tubing' in North America and you will get galvanized steel, not copper.
Lots of great suggestions from all. Every option is open.
I’ll look into the threaded rod, I just haven’t come across any yet. Small nuts will have to be available too.
As it is now, the aluminum tube buts against the undersides of the carrier PCB and smaller screws thread into it from the other side. In threaded rod, the hole would have to be expanded so the rod goes entirely through. I would need a nut on either side of the PCB to keep it from sliding down. I’d also have to check if the nuts would interfere with the carrier seating in the light. Would the inner nuts interfere with the cells? Just things I have to consider. Are these rods steel? Is that OK to conduct my ground.
With the brass tubing, I also could find some kind of small copper nail with a flat head and solder it into the tube to retain the PCB.
Just thinking about all my options. It’ll get done one way or another.
“Copper” brake lines, one make is ‘Cunifer’ (Copper.nickel/steel) are indeed very common. Volvo were the first to fit them. IMV much safer than steel lines, not to mention fitting/bending them.
When were they banned in the US? Volvo’s have them from the factory not heard anything about them having to have steel lines nowadays for the US.
I have bought coils of it with the DOT markings (one make I’m pretty sure was a US company) over here and also recommended its use to many users of a car forum that I used to inhabit a few years ago most of which were in the US. Never heard that the ones with the relevant compliances, were illegal in those days. Only gripe was the cost.
Thinking about it, my daughter’s other half replaced some lines on her 535 with Cunifer type tubing last year, and knowing him he would have checked every compliance safety regulation before buying the tubing. So i am surprised that you say it is now illegal.
While you are thinking about that stuff, why not put the calipers on the OD of the threads for one of those small screws? That’s relevant for figuring out what kind of threaded cylinder you need for a direct replacement.
Okay. I think I'm on my way with the battery holder.
Sorry wight, I meant to give you measurements on the screws, but found an easy solution. I found some brass tubing at an RC shop. They had 4mm (5/32), but I couldn't find any sort of screw or alternative that fit, so I went down a size. I had some copper plumbing nails that were perfect.
(Photo of brass tubes with copper nails and original aluminum standoffs)
I cut the brass tubes with a small tubing cutter and shortened the copper nails. Just for luck, I drizzled some liquid flux down the tubes, then coated the nails with solder paste.
At first I thought it might not work as well as I planned because when I had it all set up it was leaning and wobbling like the Tower of Pisa.
I had nothing to lose, except for starting over again, so lined it up as well as I could and hit the brass tubes with a mini torch.
In seconds everything was flowing and smoking. It snapped into position about as perfect as you can get. This thing is more solid than the original. I could probably stand on it.
I dropped it in the light with the switch just resting on the end. The tailcap tightens down okay and the switch clicks. I'm using the stock contact plate that has a spring that compresses on the positive carrier pad. It also has a brass ground ring that lines up perfectly with the nail heads for ground. I can tell by the scratches that they are making contact.
I wanted to use an Omten, but it wouldn't fit. I'm going to use this round Solarforce switch.
I still haven't figured out how I'm going to attach it, as the neg. pad sits right underneath it.
Tomorrow I'll sand the nail heads smoother. If I was going to do it again, I would have counter sunk the holes so the nail heads were more flush. I didn't think of it at the time. Then again, I might have got them off center and screwed up the alignment.
I'll probably connect all the ground posts with wire. I was originally going to make some copper rings with holes for the nails to pass through, but when I saw how shaky everything was lining up, I figured it was a lot of extra work that would end up as a lopsided failure.
While I'm waiting for my Sanyo 18500 from Illumination Supply, I'll do some refinements and figure out the switch. Maybe run some leads from the contact plate to my DMM and make sure everything is connecting.
Great work!
Nice fix. If we could think of everything before hand it wouldn’t be nearly as exciting. 
Did you torch it on its side or standing in end?
I torched it while it was standing on end. On its side it would have just fallen apart unless it was in some sort of a clamp. I thought I would have to keep reheating it to make adjustments, but it came out perfect...huge relief.
I bought a bag of copper tube clamps a while ago (I've been cutting them up for contacts and such) It was great that I found a use for the nails that came with them.
What a kicker! Those copper nails that come with the copper tube clamps? When I went to sand down the heads, I found out that they're plated steel!
I hope this isn't going to be detrimental. Can you solder to steel? I hope there's enough residual plating on the underside that I can solder to.
That explains something! I didn’t think very hard about it, but when I saw your post I thought to myself “copper nails? hmm, those must be tricky to hammer into stuff without bending them.”…. well, they aren’t copper, duh! If they were actually copper it would be like trying to hammer copper wire into a 2x4, impossible.
To answer your question, I think solder wets just fine to regular steel. Here is something to look at, but I think it’s unnecessary: Solderability - Wikipedia
Note that steel isn’t very electrically conductive. Much worse than aluminum.
You might be able to pull those nails by carefully wedging a pair of diagonal cutters under the head and slowly wedge them out. You can buy brass hardware at your local ACE H/W or hobby shop that you can use the same way. If you can’t extract, grind the heads off and push them into the tube further. Then proceed with brass.
Or get some thick gauge of copper wire at the hardware store, anneal straighten then harden the copper and slide it in where those nails were. Should be fine.
I’m not sure I’d worry about changing anything. If you solder the brass tubing to the pads the tubing sits on… at that point who cares about the steel?
Oh well, battery carriers are rife with resistance to begin with, what's a little extra.
It shouldn't be too bad. The current will still be traveling through the copper plating which is soldered to the brass tubes. Luckily I'm using a buck driver and not direct drive.
I soldered a wire connecting ground to all three tubes with no problem. The switch is stuck down with Fujik. I'm just waiting for it to set before I wire it up.(note the small hole that will carry the current from the battery pad to the switch)
I also got got the driver connected to the contact plate today. I still need to sand down those solder blobs flush.
So far so good. I'll just keep addressing each problem as it presents itself.