POR after sand blasting

[chrisdurham]

hello, I am in the middle of a chassis refurb on my 1993 chim. I am having to replace the corners of the outriggers at the back, the rest of the chassis is in very good condition considering its age. But im looking at how far ive come with it so far, the chassis is totally stripped, so i was thinking of getting it sand blasted to get rid of any other bits of surface rust there is.

Now my question is - can you use POR "rust preventative paint" directly onto a sandblasted surface, i remember reading you just paint on over the rust? anyone else done this?

Cheers

Chris

[spend]

Best adhesion with PORIMHO is achieved simply by clean - degrease - wet - leave to dry & form small rust layer.

Remember after sand blasting you still need to degrease (quick wipe of with thinners is my normal method)

Paint then adheres & can be run out, seems to sag/run on smooth surfaces.

PS Have tried preps / metal ready & found creating surface rust layer far more effective

[zed4]

What about zinc plating first? That's what Southways do

[1276]

Hi,

Use Zinga it looks like paint but is like a cold galvanize. That's what my chassis was sprayed with. Check on the Zinga web site and see, a lot of shotblasters will offer this as a protective coating for the newly shot blasted surface. I had my chassis shot blasted and Zinga coated for £150 a couple of years ago and to cure the Zinga I was told to leave it in the rain for a couple of days.

Mel.

[penno]

It worked for me I sandblastered then used the por15 marine clean to clean, then painted the por15 on. Been fine for 5 years now. Over the top of the por15 I sprayed schultz stone chip bit of an over kill but have no rust coming through at all.

[Steve_D]

zed4 said:

What about zinc plating first? That's what Southways do

Hi Dan
The process is hot spray zinc rather than plating.
Here is a video. http://www.youtube.com/watch?v=e_QrrVWet4M

The process is in fact slightly porous but the galvanic process still prevents corrosion.
Further protection can be added with a paint or powder coat. The porous surface means that the paint/powder finish has a decent key for better adhesion.

Steve
(Southways)

[Mr Supercharged]

Out of interest Steve, whats the cost of this hot zinc metal spraying followed by several coats of primer / paint / stone chip for a chassis / wishbones and all the other bits you would normally do?

[Chuffmeister]

Mr Supercharged said:

Out of interest Steve, whats the cost of this hot zinc metal spraying followed by several coats of primer / paint / stone chip for a chassis / wishbones and all the other bits you would normally do?

[marks3drtaz]

In 2007 I had my chassis shot blasted and hot zinc sprayed, I then contacted a nice man in the states from por who confused the hell out of me regarding chemical compounds etc but the final out come was to spray with a high lift gun at 12 cm and 4 - 5 coats no more. The problem with brushing is there is the temptation to lay it on for good coverage but the strength of this product uses the bond to the metal as its strength not thick layers. 7 years on? not one bit of rust any where even the high impact areas of the outriggers are perfect, this stuff does not chip or mark but some hot areas of the engine bay have a slight gold colour also por 15 is non UV stable so don't use it on your gates without a top coat.

Mark

[EGB]

See page 2 EGB on how to waxoil soak the UPPER unseen surface of outriggers for Griffs/Chims. Easy, effective and messy!

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[Mr Supercharged]

marks3drtaz said:

In 2007 I had my chassis shot blasted and hot zinc sprayed, I then contacted a nice man in the states from por who confused the hell out of me regarding chemical compounds etc but the final out come was to spray with a high lift gun at 12 cm and 4 - 5 coats no more. The problem with brushing is there is the temptation to lay it on for good coverage but the strength of this product uses the bond to the metal as its strength not thick layers. 7 years on? not one bit of rust any where even the high impact areas of the outriggers are perfect, this stuff does not chip or mark but some hot areas of the engine bay have a slight gold colour also por 15 is non UV stable so don't use it on your gates without a top coat.

Mark

Did you use any primer or surface preparation process / method between the hot zinc coated surface and the POR15? Any pictures? Have you wax oiled over any of the POR15 on the outriggers afterwards or anywhere else? Also where did you have the hot zinc spray done?

[Discopotatoes]

I've been looking into coatings and have come to the conclusion that zinga followed by epoxy 2k s the only way forward.
I was going to go HDG but that presents a load of issues befor you can paint it.
Por 15 is great if you get it right but once the body is back on it too late if it starts flaking same goes for kbs and all the other so called rust preventative paints.
I've not found any bad reviews on epoxy, and zinga or other zinc sprays are just belt and braces

[Chuffmeister]

I've seen Zinga, but I'm not sure how it will withstand impact. I seem to recall reading on a LR forum that it can flake in high impact areas. One workaround may be using something to protect the exposed parts of the outriggers?

[Discopotatoes]

Chuffmeister said:

I've seen Zinga, but I'm not sure how it will withstand impact. I seem to recall reading on a LR forum that it can flake in high impact areas. One workaround may be using something to protect the exposed parts of the outriggers?

Not if its covered in epoxy

[Chuffmeister]

Discopotatoes said:

Not if its covered in epoxy

Are you doing this yourself or having it done professionally?

[Discopotatoes]

Chuffmeister said:

Discopotatoes said:

Not if its covered in epoxy

Are you doing this yourself or having it done professionally?

Ill be doing it myself ( professionally )

[Crafty_]

As said POR15 does not stick to clean metal very well, it isn't really designed to do that. They do sell a sort of etch product that you can use on the clean metal but its not ideal.

I don't see the point of putting zinc coating under 2k epoxy, if the metal is clean just go with the epoxy straight away. Some epoxy you don't even have to use a gun - I've used a radiator foam roller before. Its flipping tough stuff - I dropped a bunch of tools on some metal painted with it and there wasn't even a scratch.

For a chassis I'd think about epoxy and then maybe a stonechip on top ?

[Chuffmeister]

Discopotatoes said:

Ill be doing it myself ( professionally )

What about under the manifolds? What are you painting there? I think Zinga had a max working temp of about 170 degrees. How about the epoxy? I guess you could always heat shield it under the manifolds?

[Discopotatoes]

Chuffmeister said:

Discopotatoes said:

Ill be doing it myself ( professionally )

What about under the manifolds? What are you painting there? I think Zinga had a max working temp of about 250 degrees. How about the epoxy? I guess you could always heat shield it under the manifolds?

Well that's a lot better than powder coat, but I intend putting some heat shields down there

[Chuffmeister]

Discopotatoes said:

Well that's a lot better than powder coat, but I intend putting some heat shields down there

I'm looking forward to seeing it done. I was thinking about Zinga a couple of months back. ChimpOnGas came up with some useful suggestions along the same route. Any particular brand in epoxy?