Preventing Sinkage

[david.g.chapman]

I do have trouble sometimes stopping the outline of the filler showing through after a repair on my +2 body.

I take great care to get a smooth finish and for a while after painting it looks great. Then the outline starts to show. I have tried using Halfords filler primer and it does not seem to help.

I normally finish off with pre-matched cellulose spray paint from a can - very easy to use.

Any tips?

[nebogipfel]

David, We are discussing body repairs in fiberglass elsewhere but to try to help.

To do the job properly the area needs to be stripped back to bare glass.

Damage should be repaired with matting and tissue and just a final skim of filler to achieve a perfect shape.

Cellulose primers are not the best on fiberglass repairs but if you use them do not overthin and give plenty of drying time between coats.

Don't flat using water until the final primer coat.

Leave the primer to dry properly for as long as you can

The problem with aerosols is they are mainly thinners so spray light coats and ensure enough drying time between coats.

Having said all this, painting a fiberglass car is not easy, there is only one way to do it properly.

As for shrinkage, we all get it sometimes so don't feel too bad Plenty of drying time between coats is the best advice I can give you.

[Tonyw]

David,

With solvent type paints it takes a while for all of the solvents to evaporate from the surface, too many coats to soon traps solvent under the dry skin of the paint, this sorts itself out eventually but then you see the "edge" or even worse lines where the rubbing down was temporarily hidden this can happen several months after a paint job. Two pack paint is better in that it goes of mainly though a chemical reaction and is normally fully hardened and cured within a week, i agree with the advice of leaving it as long as possible between coats and as long as possible before the top coats go on, in other works wait for and deal with the shrinkage.

Tonyw

[david.g.chapman]

Thanks, both of you.

I shall try waiting as long as possible between operations. I did a filler-topped fibreglass repair of a front wheel arch (a PO has glassed a steel tube in it previously, and not surprisingly it rusted, swelled and cracked the old repair) and that has not shown sinkage. So I know it can be done.

I agree, solvents in the paint/filler must be eliminated + the patience of Job.

Dave.