anybody had a subframe galvanised?

[s2_wot]

Sent my coupe rear subframe for shotblasting earlier. I've got a rough price for galvanising it but wanted to ask here is there any reason why I shouldn't.

There is paint available that can be applied to the galvanise so colour isn't a problem.

The only potential technical reason I can find is that when high tensile steel is galvanised it's fatigue strength is somewhat lowered. This is due to the very hard coating being bonded to the steel. When the steel bends / flexes repeatedly the coating will develop a hairline crack which will be drawn through the entire material.

Opinions and experiences welcome please.

[s2_wot]

"Local" suppliers of hot dip galvanising

http://www.sperringalvanisers.com/

http://www.galco.ie/

[UrS4boy]

Shane: Hot dip galvanizing can warp the subframe due to the temps involved. Strongly suggest using POR 15 rust preventative paint (or the UK equivalent):

http://www.por15.com/POR-15-Rust-Preventive-Paint/products/1/

[DS2]

I had everything from under my car galvanized and no problems but you have to let them 'dry' for a week coz its pretty soft at first when they do it

[Error404]

Shane: Hot dip galvanizing can warp the subframe due to the temps involved.

Really not a good idea to galv press formed steel.

[terrybullwon]

Could always get them Zinc plated or Zinc Barrel plated?

[Error404]

or cad plated - military spec

[terrybullwon]

or cad plated - military spec

Cadmium plating

That would be the best for sure!

Hard wearing and maluable

[S2central.net]

Sounds cheap - NOT...

POR15 is plenty good enough IMHO.

[terrybullwon]

Well zinc is about £80-100 per frame and you coat in side out. Por15 only covers the surface?

[WabTheKing]

Well zinc is about £80-100 per frame and you coat in side out. Por15 only covers the surface?

[epic]

Would you paint over the zinc or is there no point?

[terrybullwon]

You can. I powder coated over the top but you can get a reaction if it's the wrong plating

[s2_wot]

Por15 is great as it is like an elastic cover on the metal but as above there are loads of inaccesible places in the subframe that will get little or no treatment.

Powdercoating is an option for complete coverage but in the event of some damage from road debris etc corrosion can begin to spread under the surface.

Cadmium would be nice, I've a friend who worked in a place that had their own private treatment plant. I'll ask about the possibility however it's unlikely that it'll be an option.

Hot dip with zinc doesn't look like a great option now either but maybe it's worth giving it a go to see if the subframe can take it. Re cost it's somewhat comparable to powdercoating if you get a batch of parts together.

My conclusion on the failure of t'he original paint was foliform corrosion caused in part at least by the steel not being adequately cleaned before painting.

[s2_wot]

Would you paint over the zinc or is there no point?

Yes to change the colour but not from a corrosion point of view.