Nickel plating aluminium/aluminum

Hello!

I've recently stumbled onto this tutorial: High Quality (and Safe) Nickel Plating

As I've read, nickel has a quite high (80+%) light reflectivity, and seems to be relatively easy to be sourced. To be honest, after reading the instructable (and despite the fact its author says the plating wouldn't work on aluminum) I was thinking in plating an SK68 clone's head (and pill) in order to try to improve its output efficiency by recouping the light which internally hits the head's sides. I don't really know where would all that light be directed to because of its much different hitting angle into the lens…

Well, as I understand it is the alu oxide layer which prevents the plating, and that can be solved by pre-soaking the alu piece(s) with an appropiate acidic soldering flux (the same one which allows solder to bond onto it). Sounds right? :???:

Oh, well, even if the output enhancement doesn't works (should do something, don't you think?) the plating looks awesome. Now, how to remove the paint? Plethora of questions, LOL! :-)

Take care.

Cheers ^:)

Not a plating expert… but often the process involves plating metal “A” and then “B”, etc. Tin is plated to aluminum in a lot of residential and commercial AC wiring connectors. At least here in the USA it is. If tin first makes it easier to then plate nickel….

Sand paper would probably be the best fit removing the anodizing. You’ll definitely needed a strong flux to remove the oxide layer. Something a lot stronger than just regular soldering flux. You may be able to remove the oxide layer by sanding it under water (or some other liquid with a low oxygen content). I think that may work because it would never be exposed to oxygen and would prevent the formation of the oxide layer. At least that sounds good in theory.

Nickel plating an SK68’s head to try to recover some of the lost light probably isn’t worth it.

You may see a very slight increase in brightness in flood mode. Most of the cone of light exiting the LED should be hitting the lens directly. However, some may be hitting the sides of the pill or bezel. Nickel plating those could potentially see a slight increase in your overall floodbeam.

The downside of this method is spot mode is going to look pretty awful. All that shiny reflective nickel on the inside of the bezel and pill is going to create ugly rings around the image of the die. You’ll end up with a horribly ringy beam. There would be no increase whatsoever in overall throw in spot mode since all the reflections would be at the wrong angle to recycle back into the LED. You won’t get any increase to throw like you would with a wavien collar.

If you really want a brighter flood beam there are easier and better ways. I’ve tried both of the following methods with good results for increasing the floodbeam:

  • Method 1: Add a small reflector around the LED. I used a plastic reflector from an old Underwater Kinetics incan light module. Chop the reflector down and mount it around the LED. Result: Noticeably brighter flood beam. Instead of a completely uniform floodbeam, this method adds a large diffuse hotspot with probably twice the brightness in the center of the beam. Unfortunately, in spot mode, this method creates a rather horrifically ugly looking image of the reflector around the central spot. This doesn’t affect the usefulness of the beam, but looks awful in white-wall hunting.
  • Method 2: File off portions of the bezel, pill and/or body to allow the lens to retract closer to the top of the LED. Ideally the lens should retract to within 1 mm of the top of the LED. This method greatly increases the width of the floodbeam and allows virtually all of the light directly emitted from the LED to hit the back of the lens. The beam pattern remains a perfectly uniform circle, but can be twice the width (at the same distance) compared to a stock SK68. This much wider flood beam produces overall higher lumens than an unmodded light, but the actual intensity of any point on the wider spot may be slightly dimmer. This method has a number of additional advantages: (1) Spot mode is unaffected… no new artifacts are added, and (2) the entire light is shorter and more compact making it even better for pocket EDC.

Currently I favor Method 2 when modding aspheric zoomies these days. It’s easy to do and dramatically improves the light compared to stock.

0K. But that doesn't mean that is any easier than plating nickel to it. You still have to remove the alu oxide layer…

I once tried to solder a copper wire on a folded piece of aluminum foil with a drop of olive oil onto it, rubbing over the oiled surface, then heating + wire + solder. After a few attempts I only got it to somewhat stick once, maybe the piece of aluminum was too big for my 26W soldering iron. :FACEPALM:

I have a bottle of Goot Super Soldering Flux in the mail, by the way. })

That's what I was more or less interested in getting confirmation of: no improvement (could even get worse).

Seems I'd better go look for some sort of small pre-collimating plano-convex lens, as I've tested on a bigger flashlight to good extent. :THUMBS-UP:

Cheers ^:)

I believe that the internals of the SK68 are purposely left flat so that there are no reflections. I believe the reflections would mess with the optics and leave unwanted artifacts in the beam. Perhaps you are only looking for maximum lumens?
I have already messed with this and didn’t like the results

Hi Barkuti,

I do not know if the result in a flashlight would be worth it but but it is doable. Nickel plating usually is the second step to tin coat aluminium. (Etch off oxide layer, nickel coating, copper coating, tin coating.)
De-anodizing is not that complicated, see here. You will need to polish the surface and use “bright nickel”.

But beware that by touching a nickel surface with your skin repeatedly you may develop a contact allergy. Paint the outside with clear coat to prevent this.

As stated above polishing the aluminum (which would be more reflective, I think aluminum is around 90% in the visible spectrum) is far easier although you won’t gain much, if anything you’ll gain lots of very nasty ring artifacts. Having some light experience in plating copper and nickel and having done far far too much research on the topic plating on aluminum is not something you want to do at home. It is a very common commercial application used for tons of automotive applications (anything that is chrome on aluminum has a copper plate base coat). But you are talking some seriously nasty chemicals, it has to be stripped of ano then zincated, then electroless nickel plated or cyanide copper. So far I only have experience with normal acid plating using common sulfuric acid and it still scares me a little.

Hi!

No worries dchomak, after what Firelight2 said I more or less ditched the idea of plating the inside of the head to “improve” on unwanted reflections.

Tbone, some years ago we had some relatively high nickel content coins in my country (25%) and I never experienced issues with them, so I doubt that this stuff could, in particular, be problematic (at least for my person). Some concerns have raised on me in case I were to want to full nickel plate some @#$% and then give it away to someone, though. :O

Thanks to all of your contributions, however, I believe I now have a solid idea on how to copper plate aluminum, something with could be cool, safe and definitively be an improvement with regards to our electrical & thermal conduction ideals. Steps:

  1. De-anodization plus cleaning.
  2. Strong flux soaking.
  3. Nickel plating.
  4. Copper plating: High Quality (and Safe) Copper Plating.

Take care & thank thee. :CROWN:

Cheers ^:)

You could just finely polish the alu to test ideas. Done well it’s close to nickel or chrome in reflectivity though it might oxidize in time. Would be easier to un-do if the idea didn’t work.

Phil

Unfortunately it is not a yes/no decision like being allergic to something or not. This type of contact allergy can develop any time even for people that worked with the material for a long time.
The symptoms are not that dramatic and the cure is cheap - as long as you are not addicted to that particular flashlight life goes on. But for me such an allergy it not worth getting so I would avoid unnecessary contact.
A friend of mine suddenly got allergic to epoxy resin after working with it for ten years. Now he can not even stand the vapours. He had to give up boat building. He regrets not having used gloves every time.

No substance allergies yet but I developed a food allergy to anything potato including “modified food starch”; a very common potato-based processed food filler. And gout took away my beef but I’m still OK with pork products. Life-changing stuff, and some allergies are a real bugger to diagnose and narrow down since there’s so many possible causes. I try not to over-do anything anymore.

Phil

Dear goodness. You poor soul. No beef?? No potatos…… even worse no meat and potato dinners?? No potato vodka??

@Barkuti, sorry for reviving a thread, but your idea is dead in the water unless you have a way to plate nickel to aluminium.

What you need:

  1. Deanodize/clean the aluminium.
  2. Use a zincate bath to pre-plate it.
  3. Use a flash copper solution(strike plate) to be able to plate.
  4. You can then prepare the surface with very very fine sandpaper.
  5. Silver plate it.

As you can probably see, it’s hard to do, and quite expensive.