Seam Sealer

[StagnJag]

Up until now I haven't used any seam sealer under my car while removing the underseal and replacing with Hammerite. I am currently working in one of the front wheel arches and thought that it would be prudent to use it.

My painting logic was to give everything a once over using Hammerite Red oxide primer to give a good first layer of protection. Next use the seam sealer, and undercoat on top of that prior to putting the white Hammerite on top.

I bought a tin of U-Pol Grey Stripe seam sealer in Halfords, but it has recated with the primer and blistered up. Has anyone come across this before. The first time I thought that I hadn't left the primer long enough to go off - 4 hours. Second time around I left it 24 hours but the same thing has happened. I spent several days hacking off underseal and derusting so to hack off the seam sealer for a second time as well has really p*$$ed me off.

Rgds

Dave

[dasadrew]

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Dave,

I've had bad experience in general in mixing Hammerite products with other systems - be they paint, primer or whatever. On the tins here at least it says that Hammerite is incompatible with other products.

Hammerite paint itself seems to need years to go off before it stops to react with other paint systems. Just my experience.

Try a test piece primed with a "normal" primer or paint to see if it is just an incompatibility problem.

Drew

[StagnJag]

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I thought as much! It looks like I will have to go for plan B - lots of layers of paint!

[redstag]

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Just had a quick look at the upol specs and the grey stripe seems to have a veryhigh volatiles content. Interestingly they only recommend it for internal welded seams.

I would suggest you use a quality PU seam sealer that comes in tubes for use in a sealant gun. I found them much easier to use.



Pete

[new to this]

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Hammerite paint chips easy when ive been paniting mine ive used boat paint its a lot stronger

Dave

[StagnJag]

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Great stuff guys, thank you. Looks like I have a bit of research to do.

Cheers

Dave

[martin]

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StagnJag wrote:

Great stuff guys, thank you. Looks like I have a bit of research to do.

Cheers

Dave

Hi Dave, after cleaning right back, use Bilt Hamber etch primer, seam sealer, then paint. Martin.

[Sheepdip]

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StagnJag wrote:

Up until now I haven't used any seam sealer under my car while removing the underseal and replacing with Hammerite. I am currently working in one of the front wheel arches and thought that it would be prudent to use it.

My painting logic was to give everything a once over using Hammerite Red oxide primer to give a good first layer of protection. Next use the seam sealer, and undercoat on top of that prior to putting the white Hammerite on top.

I bought a tin of U-Pol Grey Stripe seam sealer in Halfords, but it has recated with the primer and blistered up. Has anyone come across this before. The first time I thought that I hadn't left the primer long enough to go off - 4 hours. Second time around I left it 24 hours but the same thing has happened. I spent several days hacking off underseal and derusting so to hack off the seam sealer for a second time as well has really p*$$ed me off.

Rgds

Dave

Had similar problem using same Hammerite stuff (After I'd done whole bare rebuilt car). I ended up using a marine (I think it was Sikoflex) sealant which is a bit like rubber and B****** expensive, but didn't react. Wouldn't touch this oxide again.

Since then I've gone for more normal red oxide primers and normal sealants without problems.

Paul

[StagnJag]

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Sheepdip wrote:

StagnJag wrote:

Up until now I haven't used any seam sealer under my car while removing the underseal and replacing with Hammerite. I am currently working in one of the front wheel arches and thought that it would be prudent to use it.

My painting logic was to give everything a once over using Hammerite Red oxide primer to give a good first layer of protection. Next use the seam sealer, and undercoat on top of that prior to putting the white Hammerite on top.

I bought a tin of U-Pol Grey Stripe seam sealer in Halfords, but it has recated with the primer and blistered up. Has anyone come across this before. The first time I thought that I hadn't left the primer long enough to go off - 4 hours. Second time around I left it 24 hours but the same thing has happened. I spent several days hacking off underseal and derusting so to hack off the seam sealer for a second time as well has really p*$$ed me off.

Rgds

Dave

Had similar problem using same Hammerite stuff (After I'd done whole bare rebuilt car). I ended up using a marine (I think it was Sikoflex) sealant which is a bit like rubber and B****** expensive, but didn't react. Wouldn't touch this oxide again.

Since then I've gone for more normal red oxide primers and normal sealants without problems.

Paul

Can you remember what sort of Sikaflex you used? There seem to be loads of different sorts!

Cheers

D

[Dave M]

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Dave

I used Tiger Seal when I did mine, smoothed it off with white spirit, havent used hamerite over it or under it but it might be worth trying.

Dave

[Sheepdip]

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StagnJag wrote:

Sheepdip wrote:

Had similar problem using same Hammerite stuff (After I'd done whole bare rebuilt car). I ended up using a marine (I think it was Sikoflex) sealant which is a bit like rubber and B****** expensive, but didn't react. Wouldn't touch this oxide again.

Since then I've gone for more normal red oxide primers and normal sealants without problems.

Paul

Can you remember what sort of Sikaflex you used? There seem to be loads of different sorts!

Cheers

D

Hi Dave, had a look in my paint drawer and found on old cartridge - would you believe it I punched in the side just where the numbers are....(only way to get it out after the stuff sets like rubber in the top if not used). It looks like 221 which ties up with this but no guarantees, the price typical chandlers but was still expensive - I think I got mine from Partco.

http://www.theyachtshop.co.uk/items/...577-detail.htm

Since car still not on road I can't verify its effectiveness but I did use it to lock a rudder post plastic bearing on ayacht - and was till intact a year later!



Paul

[StagnJag]

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Great stuff, thanks Paul.

Duly ordered.

Rgds

Dave

[Sheepdip]

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Good luck Dave. It worked for me but I won't be using Hammerite primer again! In hindsight wish I'd taken the stuff off and reapplied normal oxide. Not because I had a problem with it but I ended up using several cartridges which was pricey.

A friend gave a tip when applying seam sealer - squeeze it on then brush with a paintbrush in thinners - gives a great professional finish. Not sure it worked with this stuff tho.

Paul