Springs!!

the old dude can crank out some mean hot rods of his own! :stuck_out_tongue:

While we’re both here, can you fill me in on the kinds of problems you’ve run into when soldering to steel springs? EG are there specific springs you had trouble with, was the trouble purely cold solder joints because of the way steel acts, does being plated help, etc. TIA

I forgot that new powerful side of OL , how could I !!

Thanx Again djozz!!

I posted detailed pics (somewhere??) in a BLF thread comparing the cheap stuff to the better grade Chemtronics braid (ex: http://www.techni-tool.com/Top-Brands/Chemtronics-Desolder-Braid). The difference is radical in my opinion in the design, weave, density - it also solder wicks better! I converted from the cheap stuff to Chemtronics, but eventually switched to quality 22 or 24 AWG wire because I feel the wire is still better to work with and holds up better. I've had numerous failures over time of the cheap braid on springs.

Also a big +1 to O-L's post. Most of the time the spring is seems to be 95% of the volt->amp drop of the tailcap - surprisingly the switch's do pretty well, accept the low budget light ones. I don't have hard #'s to back this up - only from lots of testing of hard-wiring around the tailcap assembly vs. stock tailcap vs. copper wired spring tailcaps.

wight, yes

not plated, it takes so much heat to get the solder solidly adhered that it weakens the spring. plated, the plating starts cracking off. I’ve found steel springs have let go of my bypass, usually on the really cheap lights. Pretty much replace springs as a habit now. Been doing that for a while and really haven’t had much trouble since.

Thanks for the testing Djozz. Nice how well your spring compares to the much smaller nanjg spring. It looks like the solder points shorten the effective length of the IO spring more than yours.

I wonder if rather than even trying to solder to the spring one just soldered to a contact plate that sat on top of the spring and solder the other end of the wick or wire to the pcb pad. Use the spring for its compression strength and don’t worry about an electrical connection through it. Also, if using insulated wire is it even necessary to go down the inside of the spring.

A common technique in spring bypass wiring is the wire outside the spring - depends on clearances, pinch points, etc. which method is better I suppose. I believe vinh uses that a lot, think others do as well. An inner bypass wire certainly is more at risk to reduce spring compression, but I try to carefully test that out. I haven't used outer bypass's much - I'll tend to use a 24 AWG wire in smaller diameter springs. I do though try to get the bypass wire soldered to the pad and spring at the bottom, not just the spring. The top soldering is more problematic. I suppose a nice little copper/brass disc to solder would be a better solution - then that disc gets soldered to the top of the spring. So even for a crappy spring, if the disc loosens from the spring, it would hopefully still be dangling over the spring (could be manually positioned) but if the wire holds well, you still got a rock solid electrical connection.

Downside of outer spring bypass's (in my mind??) is if the top solder joint breaks, that wire is really dangling out there. My thinking would be that under compression, a broken connection for an inner wire would still be making electrical contact somewhat - less risk to ground out on something.

I went with double braids on mine… Just sent it out this morning… Goodbye sweet light. I tried DBC method and I couldn’t get the spring to compress enough. I have to try that copper button top OL.

If you have a good electrical path and good copper heat path to the pill, you can go dd without noticeable sag. :slight_smile:

Agree with OL- unless you don’t plan to braid. Intl has the best but like 3 bucks a spring :expressionless: Better come with some boobs

Djozz,

You are hard worker and you are 100% into your hobby...

Glad that you tested that Phosphor broze springs because I new that they are better than original steel springs only by my luxmeter, always 10-15% more brightness when I swap steel with this phosphor bronze guys (they look like a copper to me).

Your custom spring looks excellent. Need that kind of spring with ∅ 10mm bottom base and 11-12mm height. This springs are much more flexible than steel ones and they are battery friendly not pressing pcb so hard as steel. Excellent for single cell 18650 lights up to 3A.They also accepts solder paste better so they can be braided or wire bypassed to if needed.

I tried braiding steel springs with braid and wires(contact and switch) but lux results were same as stock until I tried copper bronze ones. I really don't know what happened but lux number instantly jumps.

I only wish to try beryllium copper springs but no one has this puppies(at least at China stores).

I found some interesting suppliers for copper like springs here: http://www.aliexpress.com/item/Free-shipping-Phosphor-Bronze-spring-for-flashlight-DIY-100-pack/1062864560.html and here: http://www.aliexpress.com/item/10X8mm-Solid-Copper-Spring-For-High-Output-LED-Flashlight-Driver-Circuit-Board/2054366124.html

The phosfor bronze springs that you link and the Fasttech one are all about the same size, perhaps they all sell the same bit smallish spring?

Nice springs and nice work! There is nothing wrong with them and given the "actual size" (diameter and length of "wire") you are almost neck and neck with CB springs. If you are willing to dispose of some at the cost you mentioned you may get rid of the majority. I would definitely take a few to a dozen ;)

Yes it seems all selling same stuff. There is only difference in their description (copper, carobronze, phosphor bronze).

They should get more sizes for them, and more thickness options although you can rework them with some conical tool (strecth here and stretch there) To bad beryllium springs for flashlight are not broad on the market...

Hank of intl-outdoor asked me about the precise height of the tested intl-outdoor spring. I understand he is concerned about tests of the springs that he sells. I post my answer to him here as well because I think that it is fair to tell any concerns about my limited tests.

Yes Hank from IO should not be to concerned about this issue this is small spring anyway and most of springs will compress a bit especially when they are tight fit with battery.

Springs with bottom base from 9-10mm and height 10-12mm thickness 1mm are most common bigger springs. Hank as your old buyer please get that famous Beryllium copper springs...

For bigger springs my vote goes to this dimension: ∅ 10mm bottom, height 11mm, 1mm(or bit larger) wire thickness which should fit to most tail switches.

or smaller one: ∅ 7mm bottom, height 10mm, thickness 0,8mm (that could replace nanjg spring also)

Thanks for the testing Djozz

Thanks for the great testing. :beer:

Did you see Simon / Shenzhen Convoy Electronics carries Phosphor Bronze springs? $2.75 for 10. High 10mm, bottom diameter 7mm, diameter 0.8mm.
Orange coppery color from the picture, for whatever that is worth.

They sure seem identical (size and color) to the FT ones: fasttech.com - springs djozz listed in the OP and tested, just over twice the price.

Thanks djozz for your effort writing, thinking, testing, photographing, editing, uploading, copy, paste :stuck_out_tongue: Thank you any way

So what’s currently the best recommendation for springs, and for bypass wire — for ordinary lights, and for hotrods?

And does anyone make springs with bypass wire already connected (say with a spot-welder)? Because I find it hard to get bypass wire soldered to each end of a spring without overheating the whole spring.

Try to put a little dab of flux on the surfaces (the wire end & spring) you want to mate with solder, and you will find that you don’t have to heat them so much to get them nicely joined :wink: