Problem with primer on chassis
 

Has anybody seen this before ? Have been having a wee test with my metal primer..Dulux Metalshield in grey ...i painted a bit over the front frame last night and when i went out this morning there was brownish blotches that looked as if it has come through the primer...especially bad around the welds...now i did give the rails a good polish with flappy disk and a final wipe down with acetone so i thought it would be contaminant free....the paint has been in the garage for the last few months could it be gubbed due to extream cold ?? would be pi$$ed off cause it cost me a few quid and unused

Its dulux metalshield for use on new steel...or so it says on the tin i used mig machine with a Co2 /argon mix have just been out takin pics of it so i will upload when i get a min cost me 75 quid too as i intended doing the garage doors with it come the summer time....

Should be pics linked to my photbuckety thing

[IMG]<a href="http://s1229.photobucket.com/albums/ee466/Andy_Locost/?action=view&amp;current=P1170096.jpg" target="_blank"><img src="http://i1229.photobucket.com/albums/ee466/Andy_Locost/P1170096.jpg" border="0" alt="Photobucket"></a>[/IMG][IMG]<a href="http://s1229.photobucket.com/albums/ee466/Andy_Locost/?action=view&amp;current=P1170097.jpg" target="_blank"><img src="http://i1229.photobucket.com/albums/ee466/Andy_Locost/P1170097.jpg" border="0" alt="Photobucket"></a>[/IMG][IMG]<a href="http://s1229.photobucket.com/albums/ee466/Andy_Locost/?action=view&amp;current=P1170098.jpg" target="_blank"><img src="http://i1229.photobucket.com/albums/ee466/Andy_Locost/P1170098.jpg" border="0" alt="Photobucket"></a>[/IMG]

There you go.

I think the paint has reacted to some tiny particles of metal dust that the wipe down with acetone has missed, as they have become trapped in the tiny crevices where the weld pool has been , just a thought :)

Chassis is looking great Andy :cool:

Tho maybe its the angle of the photo but the drivers side of the roll bar "looks" higher than the passenger side ? probably the angle of the photo .

cheers
andy

Best stuff to use if not having it powder coated is actually chassis paint and designed for said application. It stays rubberyish so will absorb a knock or 3. Anything else will and does just chip.

What the opinion on hammerite as a chassis paint?

It is Andy...but what a pig of a thing to measure ...its only tacked in place at the moment for that very reason

Chuck roll bar on the floor and get a straight edge that spans the roll bar...measure from this to the underside of the tube to not only get both legs the same but you get the cut angle at same time........simples:D

i used hammerite, but i found it chips real easy and its a pig if the temperature isnt right so i coated the chassis in zinc paint first then hammerited. To be honest i wish id sprayed rather than brush painted but its done now and the only chassis rails which will be on display are the cockpit ones which im going to spray orange.

Dulux have been making this for few years.
If it had been the cold, the primer will have small crystal in it, i would say it either was a contaminant or it was not stir for long enough as it oil based, and you can only use oil base products as a top coat.

As others have said, use a chassis paint designed for this job or power coating, hammerite is ok, but doles quite quickly.
Terry

I used that chassis paint from frosts. I'm assuming its the stuff they make them anti-tank rounds out of cos its freaking nails. They ain't kidding either with the warnings on the tin. Don't let the paint touch the lip of the tin or when you put the lid back on it seals the lid onto the tin forever!


Por 15 by Frosts Restorers

looks like surface contamination to me. use panel wipe rather than acetone, they tend to throw other crap in with cheep acetone where as panel wipe from a proper paint supplier is made for the job

i spent nearly a day sanding my chassis with 300grit paper before i painted it, sprayed it with epoxy mastic 121. in the year its been on the road i have been out in the rain slat grit etc etc so far no rust just a dirty car :D

the key is in the key. nice scratched metal surface helps the paint stick.

Thanks for all the replys...Ash G i spoke to the painter in work today and yes it is contamination i need to wash it down with sugar soap ...he also told me if i had spat on it it would have not come through !!! but think he may have been at the meths last night !! I dont have any spraying guns for my compressor and funds for the next few weeks running short due to TAX MOT on Family car so a brush on topcoat would be in order ...how much of that hard tank type paint would the chassis need ?

Just been out and fixed this...i thought a few mm would sort it but after using a measuring stick and a matchbox trick a pipefitter at work taught me 15mm got ripped off the right leg !!!....now its spot on and fully welded....now for the cross bar and downstays...

Nice one Andy , sounds like you are really cracking with your build :cool:

cheers
andy