18 replies to this topic

[tiger99]

As electroplating has been mentioned, I would point out that it should never be used on stressed parts unless precautions are taken to avoid hydrogen embrittlement. Plating companies who supply the aerospace industry, for example, will know what to do. Those who do only decorative plating may not. It invariably involves a high temperature bake after plating, and would be absolutely essential on a subframe.

But I must say that, if done properly, which it can be, a nickel plated subframe would look rather nice.

I think the Peugeots were made from electroplated steel sheet, which is cheaper overall than galvanised as the zinc is thinner and the surface smoother. It will spot weld, but the electrodes need more maintenance than with bare steel. But for some reason it did not work very well, as they had a reputation for rusting.

I would like to know more, to know what to avoid! And, what do we know about the finish on the longest-lasting cars?

[charliedurrant]

I've had both my front and rear subframes powder coated by a reputable local company who Cunard use to powder coat all their exterior light fittings for use on their cruise ships.

the company I use are very good and completely blast the frames before pre-treating with some kind of primer, then they are powder coated. I've had no problems at all with these frames, but do agree with what other have said about poorly applied powder coatings.

Cheers, Steve.

Steve,

If the company costs boat parts then they will be very good. My local company (Windridge coatings) paint marine parts and they prime the metal with a powder primer then top coat. It is very easy to mess up two coat powder coating and in my opinion if the company you go to knows how to do it and does it on a regular basis then they will be good at what they do!

However - galvanise all the way. Just take a look at those railings you see in parks - very ugly but they have been there for twenty years being bashed around and are still that ugly grey colour...

Charlie

[Shifty]

I'm sure we've talked about galvanizing rear frames before and there was some concern about warpage?

There was a company who supplied these and i'm sure that they had to be held in a jig.

Theres also the issue of drainage as well, the galv solutions needs to be able to drain away easily so in the enclosed parts drain holes would need to be drilled.

[charliedurrant]

I'm sure we've talked about galvanizing rear frames before and there was some concern about warpage?

There was a company who supplied these and i'm sure that they had to be held in a jig.

Theres also the issue of drainage as well, the galv solutions needs to be able to drain away easily so in the enclosed parts drain holes would need to be drilled.

Yes, enclosed sections must be drilled - nothing fancy just a hole else the section can burst. As to warping I'd be surpprised if a sub frame would warp. I regularly have 2.5mm wall thickness tube galvanised for my wife's garden furniture company and it is fine. Any galvaniser should be able to advise though although I doubt they will give a guarantee!


Charlie