power coat verses galvanise
 

What do people think? for parts that I can remove and clean up, before refitting. I need to stop the rust.

Graeme

I used to make bits for boats. You cannot beat hot dipped galvanising.

Powder coating lifts off the surface it's supposed to save, you will get rust underneath where you can't see it

If they are going to see any weather galv them as said power coating will lift and rust underneath
H

you just have to be careful not to warp it if galvanising. the other option for small parts is passivating.

Please note, I specifically said to use the "hot dip" process. there are a number of places that call spraying on a zinc based paint "galvanising". Only true hot dip is good. the rest are useless.

Hot dip galv may not lend itself well to small complex parts.

I would try to find a local plating company and go and have a chat. There are electroplated and passivated coatings that can give good protection when properly matched to the expected environment.

Absolutely, hot dipped is far the best way to protect steel, any closed box sections like side protection bars should be drilled in several places (in a discreet area) prior to hot dip galvanising to allow the zinc to flow through and coat the inside and to prevent heat/air pressure from warping it.


My Dad has a boat trailer he designed and had built in 1982 in the back garden that was hot dip galvanised - still looks new today.


Yeah its not so good for small parts, but for protection bars and roof racks on a 4x4 its by far the best process.

Thanks for the replies, Griff I don't suppose your dad got the trailer dipped in Poole? if so where

Graeme

Hi Graeme


I think the trailer was built near Bristol somewhere, cant remember the name of the company, but I had some parts galvanized about 10 years ago in Poole and these guys did it:


Wessex Fabrications - Gates, Railings, Fire Escapes in Poole and Bournemouth


worth giving them a call for a quote.


the only thing to bear in mind with hot dipping is that any threads might need to be cleaned out afterwards with a tap.

Thanks Grif, I will call them.

Graeme

Very true, I machined up a set of keel bolts and had to put them back into the lathe to clean them. Quite a task as zinc is soft and clogs cutting tools easily.

Some places can actually "spin" threaded parts to help alleviate this problem.

I've used Wessex galvanizers several times for LR chassis and other bits (side sills/B pillers etc)

always been good and fairly reasonable in price.

they're in Southampton area, not far off the A34 heading south.

Anodizing is for Aluminium, chrome is for steel.

Anodizing ally is a great way to go. Surface toughens the ally, and stops the black rub-off, and prevents corrosion.

Observe that thin plates will warp with warm galvanising.

Check the doors

http://i894.photobucket.com/albums/a...C388EA0F43.jpg

Rarely do I venture in to the world of 4x4's but having started work at a well known 4x4 specialist, I thought I'd poke around here. :thumbup1:

Is it possible to powdercoat galvanized steel parts to maximise corrosion resistance and have something that looks good?

Hi Steve, yes it is
I've had a number of chassis galv'd & powder coated, though I prefer to get Items in impact or high wear areas like bumpers and steps plastic coated.
loads of parts on my 90 are galv'd & a mix or powder & plastic coated.

I did a 90 chassis in galv & gloss black plastic coat for a friend 2yrs ago and a wipe over with a damp cloth makes it looks like new.

regards all

Gren

As with all painting, surface prep is key to getting a good finish with powder coating over HDG, but basically you should powder coat asap after the surface prep before zinc oxidation sets in.


Here is some good info:


Preparing HDG for Powder Coat | American Galvanizers Association