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Goggomobile
28th Feb 2016, 10:39 AM
Hi all
ive also got lots of chrome bits to restore.

Im guessing an old topic but I don't have much of a clue. I took some bits to a plating place but the price blew me away $70 a hub cap .. I had sand blasted some caps since I thought this might make it easier. Not the case as the pre treatment is important.

I am looking for somewhere I can sent my bits in Australia. I recon it would be cost effective. Has any one been down this path.

- rear bumper
- front bumper
- front griller
- 4 hub caps

Randal

YBAF
28th Feb 2016, 11:28 AM
Being fashionable, I hear black is the new chrome.:cool:


If yer restoring, then yer up for the cost of plating I guess. Although, them pressure pack chromes are getting pretty good now-a-days.

KBs PensNmore
28th Feb 2016, 04:21 PM
Hi Randal,
The biggest expense in Chrome Plating is in the polishing, which is an art in itself, I had a workshop next to a polishing works and saw what was involved.
The finish has to be like glass, really smooth, any blemishes/scratches, stick out like the proverbial dogs????, to save a lot of the costs you'll do it yourself. You'll need a linisher with a multitude of belts all with different grits ending up with scotch brites again in different grits, plus a bench grinder with various polishing mops and compounds. Contact the Sandpaperman, he advertises on the WoodWork Forum and is in your neck of the woods, he should be able to advise you on what you'll need. Be prepared to get hosed down before you're allowed inside, SWMBO won't allow you inside, let alone the shower, you end up filthy from the metal dust, the blokes next door were blacker than the ace of spades. The items done next door, were centres for chromed wheels, straight off the press from ROH, they took about an hour each and they weren't rusty!!!!
If the rust is to deep, they'll need filling, usually bronzing is the filler, so you'll need access to Oxy acetylene or LPG as a heating source, don't know if the MAP's will do the trick? Someone else could chime in with that reply.
Hope this helps,
Kryn

jhovel
28th Feb 2016, 07:20 PM
Just another snippet of information:
I lived a few doors up from a specialist bumper bar repairer in Richmond, Vic in the early 70's for a while. Obviously I went and watched and asked questions. as you do.
They would dechrome everything first (electrolytically). Then, after all the steel repairs - panelbeating, welding, linishing etc - they would level surfaces to something like 600 sanding equivalent. Then they would plate them quite thickly with copper - maybe a few hundredth of a millimeter thick or more - then start polishing. The copper plating filled small scratches and irregulaities and seemed to be thicker on sharp edges. The polishing made much of the copper disappear and everything ended up very shiny.
The parts went back into the copper bath (But a different one. Not sure what the difference was). The plating was quite thin, as the polish didn't appear to change, just the colour was an even copper colour at the end.
Next came a nickel plating bath with changed the colour and made the metal very slightly glossier. I was told that it filled the microscopic scratches left over. The chrome coating on top of all this is actually EXTREMELY thin and took literally only seconds. They used to joke that they did that for free. The actual cost was in all the work up to the chroming.

Master Splinter
28th Feb 2016, 07:34 PM
For some stuff you might also want to consider electroless nickel plating. Caswell Australia sell plating kits and they are popular with car restorers (especially things like zinc plate for screws and brackets and other car items).

malb
28th Feb 2016, 10:46 PM
Following from Joe's contribution above the first copper bath is a high current density one to pile on a fairly thick layer quickly. This is then given the final polish and buff. This layer is effectively a conductive body filler, i.e. it fills the pores and abrasive scratches etc in the base metal, and any transitions between base metal and weld, brazing etc. The layer is very soft and slightly pourous and polishes away with buffing, to give a very smooth surface. Without this layer to seal the job, there is a danger that welds etc can be undercut in successive baths to make than more obvious than they were before plating.
The second copper bath is a low current density one which deposits a very thin and even layer over the high density copper to seal the surface.
The nickel bath is effectively a primer coat as chrome is very difficult to get to plate onto most other metals in a 1 step process, but nickel plates onto most parent metals easily, and chrome sticks to nickel like unwanted waste to a blanket. Nickel is a lot softer and less durable than chrome and nowhere near as shiny unless buffed, whereas chrome is tougher, brighter, and way more durable than nickel.

Years ago, plating costs were largely based on polishing labour, with a bit to cover the establishment of tanks and baths, consumables and profits. Now days the most significant element is the cost of meeting OHS, EPA licensing and inspection, registered waste material disposal and similar costs, which can run to about two thirds of the total running costs of a plating plant, then the polishing labour, then the costs of tanks, consumables and profit. Gone are the days when you would use and top off an acid or cyanide solution for a few months then flush it into the local creek or drain and scrub the tanks out and pour the residues down the driveway into the gutter, but this was fairly common into the 70's and 80's. Back then, polishing was reasonably cheap, so plating was also, but employees (and in some cases employees of neighbouring businesses) frequently died of work related diseases in their 50's.

bob ward
1st Mar 2016, 12:31 AM
FWIW I've used Ipswich Electroplaters for chrome plating with good results.

A cheap work around for diecast, (which most platers are leery of) is to have it stripped then buff it yourself and clearcoat it. Assuming the diecast is not rotten etc etc.

But yes, be prepared to dig deep for chrome plating.

AndrewOC
1st Mar 2016, 12:50 PM
I certainly agree that plating is a very expensive part of restoration- why I'm a fan of commercial vehicles. It is very easy to spend more on restoration, than what the vehicle will be worth for resale.
Friends in the Perth branch of our car club have recently got car parts plated in Bali !?!
regs,
A.

Goggomobile
2nd Mar 2016, 09:39 PM
Thanks everyone .. This was a great read. I never realised how much was involved in this. I have a new appreciation for re- chroming