Zinc Plating help and recommendations

[mattb130]

Hi all,

Currently part way through doing a suspension refresh.  Today took the wishbones and uprights to be zinc plated only for them to be turned away as they didn't want to acid dip them for fear of embrittlement. In fairness I'd only given the uprights light wire brushing and the wishbone were as they were when they came off the car.  

Just wanted to know for those who have zinc plated theirs what state did you send them in? does it sound like this company was just being picky or looking for a reason not to do the work as it would have been more effort to prep?

thanks in advance 

Matt

[jonnyfox]

JW Rudge & Co Ltd did a great job on mine after shot blasting elsewhere.  Didn't mention that as an issue and I didn't have an issue after the 4 years after it was done. Mind you they didn't do many miles. Either way, still look perfect. 

[winthattt]

I considered zinc plating and it could be an issue so I decided against it.  You can get hydrogen embrittlement but it would require some analysis to see if it’s significant, I did not have the skills or software to do the calculations.  I’d just get them blasted and painted or coated.

 

[timbo]

Since the wishbones were zinc plated originally, is it fair to accept that Lotus had already considered the possibility and decided it wasn't an issue? One of the commonest ways to reduce/eliminate is to bake after plating, so zinc plate then a clear powder coating might be one avenue as the initial heating of the parts prior to spraying would serve as the baking stage.

[DeanB]

I'm not convinced by powder coating though.  I've never known it not chip, and wishbones are obviously vulnerable to stones and gravel attacks.

[mattb130]

So I think the company just didn’t fancy do the job as spoke with another company yesterday with the parts going in today. 
 

Will then either clear coat them if they look good or paint them if they don’t. 
 

Where do people stand on body coloured wishbones? (The body is more orange than the entire cast of only way is Essex). Only seen the adverts never watched it.  

[winthattt]

In the end, I have always just put a coat of clear waxoyl on the wishbones whenever  I remove a wheel (which is quite often).  They don’t look lovely but they are in great condition. 
 

It’s a good point that they where plated originally, I’m not sure what sort of treatment they applied, I don’t think it’s zinc galvanising as it fails far too quickly, 

[timbo]

As far as I'm aware it was zinc with a yellow(?) passivate. As with any surface finish, good surface preparation is vital for durability. Possibly that coupled with brake pad/disc dust, moisture, etc. is going to give them quite a harsh time.

Powder coating would help to keep stuff like that off the metal, but yes, it will chip given impact with anything hard/sharp. At least if it's chipped, the zinc should help to reduce corrosion as its purpose is sacrificial.