22 replies to this topic

[Mani]

Hi folks

 

Just a quick question. What would be cheaper- powdercoating or zinc plate + passivate?

 

Cheers

Mani

Edited by Mani, 05 December 2015 - 06:21 PM.

[fezzasus]

How about which would be more effective? Powder coating isn't that durable, once it's penetrated, it will flake along the whole interface, whereas zinc plating is bonded to the interface so won't fail with one scrape.

[Mani]

I know zinc plate is more effective. Just want to get a rule of thumb on what tends to be more expensive.

[FLD]

Why not do both. 150 for full plate and passivity plus 100 for powder coat.

[TheHood]

IME you'd be amazed how much rust seemingly perfect powder coating can hide, but each to their own I guess.

[deano01]

Why not do both. 150 for full plate and passivity plus 100 for powder coat.

 

 As FLD says. That's where my money would be spent. Protect and cover rather than just short term cover.  

[Madmitch]

Agree with everything above.  We used to use Cadmium and passivation until Cadmium was outlawed as a heavy metal, then we went to zinc and pass which is just as good.  There was once upon a time another surface treatment, long gone, called Parkerising which if I recall was a phosphating process.  Powder coating may be fine for garden furniture but absolutely not for wishbones upon which your life depends - don't even think about it! 

Edited by Madmitch, 05 December 2015 - 11:12 PM.

[Spitfire Engineering]

 

Why not do both. 150 for full plate and passivity plus 100 for powder coat.

 

 As FLD says. That's where my money would be spent. Protect and cover rather than just short term cover.  

 

 

Mainly because the two processes are not easily compatible, there are many issues with the bonding of the powder onto plated steel, even worse if it has been passivate plated as well. It will not take to laquer at all (the third stage of zinc plated treatments)

If you really want to go down this route I would suggest a company that does both and understands the issues.

If you go to a plating company and then onto a seperate powder coating shop you could easily end up with finishing issues and the chances are each will blame the other.

 

Probably best to decide exactly what your priority is, display finish or protection?

 

For protection 3 stage (zinc +chromate + lacquer) is probably as good as it will ever get with this process. Not good with stone chips though.

For even higher protection you can look at the range of flouropolymers, Xylan for example but these are not only expensive but also very reliant on pre treatment and correct application methods.

I was recently shown a Xylan coated product fitted to an Elise which was corroded to about 50% of it's surface area after just 2 years. So much for superior protection.

 

Powder coating is much better for damage protection but if not prepared correctly will also peel, or worse seperate from the steel without flaking so you cannot see what is happening under the skin as mentioned above.

 

Personally I would use a quality company offering the 3 stage zinc and just keep an eye on it.

 

[Mani]

Anyone know of a good compamy that does quality zinc plating in Staffordshire or Derbyshire? I have made up my mind. Zinc it is. Powder coated suspension could just end up with hiding problems later on.

[Spitfire Engineering]

The only people we use are these, quality is second to none but probably not the cheapest.

http://www.allenchro.../services/zinc/

 

Not exactly local though.

 

[GiGo]

Google is always a friend: https://www.google.c...lating stafford

[Mani]

Thanks. Google unfortunately doesn't really tell me if they are any good.

[FLD]

Brinksway in Stockport are ok. You can use a chemical etch to get powder to stick to passivated zinc. Will have to look out which one if you want to Persue it. Not rocket science but needs some care as gaz eludes to.

[Mat Jackson]

Just a comment - and I know zinc playing is better than powder coat. I ran a Westfield for 10 years with powder coated chassis and suspension parts - and never had any issue with flaking or peeling. It may not be as good as plating - but is still pretty robust and reliable. I've just redone all my suspension on the vx and gone for powder coating - although it is only going to be a dry weather weekend car. Total cost for all suspension parts - including hub carriers- was 150 plus vat. I didn't feel the extra expense for playing was worth it considering how the car will be used and how well it is looked after

[JG]

I wouldn't powder coat again. 

 

Need to redo mine which have started to rust after 4 years. 

[Kieran McC]

I wouldn't powder coat again.    Need to redo mine which have started to rust after 4 years. 

Same as mine😠

[FLD]

Did mine about 3 years ago with plate and coat. Few chips but perfect.

[JG]

mine were the same, good for 3 years, not 4.5

 

[Mani]

Thanks for all your comments folks

[haggi961]

Best way is to zinc plate, then T-wash so the powedrcoat will then take. Another way is zinc plate then 2k clear por 15 paints straight over them.