Caswell tips and tricks

[ducpainter]

Yes, IMO you can.

'tiz thinks abrasion is a good idea.

I think because the access is so limited, the chemical will either work, or not.

It has seemed to work if coverage is good.

I will say... in my experience there is no way you can get 100% coverage regardless of number of coats if you don't thin the product.

Good luck.

[ducatiz]

Checking my understanding, is it necessary to wash out a virgin, never-seen-gas, tank with acetone, soap and water, or Marine Clean?  Can I can skip this wash-and-dry step and get straight to lining?  I want to get this prep step right.

Thanks,
Jeff

Nah, you don't need to.

I would try to rough up the surface some -- use a finishing brush with hard plastic bristles.  You won't get everywhere but it helps adhesion.  Do not use the nails as in the Caswell directions.

[jgrm1]

Nah, you don't need to.

I would try to rough up the surface some -- use a finishing brush with hard plastic bristles.  You won't get everywhere but it helps adhesion.  Do not use the nails as in the Caswell directions.

I asked my question about prepping a virgin tank at the Caswell site and received this response:

...Yes, you can skip the solvent and water, but we don't advise skipping the drywall screws. The surface of the plastic tank needs to be roughed up to ensure adhesion of the sealer...

This agrees with what ducatiz has been saying about roughing up the surface.  Now, to figure out the most thorough method.

-Jeff

[ducatiz]

I asked my question about prepping a virgin tank at the Caswell site and received this response:

...Yes, you can skip the solvent and water, but we don't advise skipping the drywall screws. The surface of the plastic tank needs to be roughed up to ensure adhesion of the sealer...

This agrees with what ducatiz has been saying about roughing up the surface.  Now, to figure out the most thorough method.

-Jeff

the problem with using the screws is that people HAVE gotten one or two stuck in the tank.  there are too many crevices which are small and a screw will get stuck.  the inner surface is small.

Caswell does not have ANY experience with the nylon tanks, they have rebuffed my attempts to get them to test it in-house.  He is giving his opinion based on zero experience.  His product works so far -- there are people with caswell-coated tanks that are 2 and 3 years old -- but i'd rather have something more concrete. 

Using screws (or nails) is fine for a metal tank, the inner surface is hard and a screw can't get stuck.  IT's a great way of removing scale or rust before etching the tank.

But with a SOFT nylon surface, you're playing with fire.

[jgrm1]

I remember reading about the "lost" screws.  You mention using a brush except it is difficult to reach all the surfaces.  I was wondering about grit blasting, but then you risk embedding the media in the surface of the tank or damaging the surface. 

-Jeff

[ducpainter]

I personally would avoid grit inside the tank.

The sealer should encase any you don't remove, but it will make a mess, and you can't get everywhere even with that method.

I have used the drywall screw method and it is possible to get them all out.

I still say that the properties of the epoxy will give adequate adhesion on a new tank regardless what you do to prep.

All this coating needs to do is stay there. It isn't like a jb weld repair that you're going to thread and bolt a manifold to.

[ducatiz]

I remember reading about the "lost" screws.  You mention using a brush except it is difficult to reach all the surfaces.  I was wondering about grit blasting, but then you risk embedding the media in the surface of the tank or damaging the surface. 

-Jeff

a detail brush.  basically a hard plastic toothbrush.  major pain to use but you can get most of it.

[jgrm1]

I asked Caswells which tint they recommend found locally that works with their liner.  Their response was:

...Any dye that works in oil based paint...

They also referred me to this FAQ on their site:  http://support.caswellplating.com/index.php?/Knowledgebase/Article/View/83/0/can-you-tint-gas-tank-sealer

-Jeff