Micro blisters from 2pack on fibreglass

[millard]

I had a complete respray about a month ago and I have just noticed a number of very small blisters showing through (they seem to sort of be in lines, others are just random). The car previously had some in the same area before I got it sprayed, I am about to go back to the bodyshop to get it sorted but dont want to get fobbed off, any ideas on the cause?

Thanks

Millard

[steve_D]

It's quite common for air bubbles in the gel coat to break out when the paint is cured in the oven. The reason they are in lines is that there was air in the brush when the gel coat was painted into the mould. The brush then spread a line of bubbles in the coat.

Most body shops will bake the body before they even start to prep it for spray so that they force the air out first.

Steve

[shirley temple]

this is a common problem on early Lotuses, From my understanding its moisture not air that causes the problem, old gelcoats are porous and will absorb moisture, which when subjected to heat (sun, engine bay, cabin from heater) will break out as microblisters. I'm not 100% sure of the cure, however I do Know that any prep work on these cars must be done in a warm dry environment, "wet flatting" is an absolute no no as it re introduces moisture.

Club Lotus have published loads of info about this over the years, Email me if you want me to have a hunt through the back issues for some more info.

sorry to hear you've got problems

Mark

[millard]

Thanks for the info, I just wanted to make sure that when I go back to the bodyshop they dont try to give me a cock and bull story. Spent a lot of money and not very happy with the job, trouble is I paid upfront!

[apguy]

If its tiny blisters then its what we term as "Solvent Pop"

Its nothing to do with the fibreglass. Its the application of the paint. It means that the solvent in the base coat hadn't all evaporated before the next coat was applied.

Only one remedy - repair of the affected panels.

This only applies to solvent paint. Waterborne products have their own set of problems.

[HeyAndy]

I had this on my TVR, I prepped all the bodywork to reduce costs, wet-flatted and it turned out that it was solvent popping. The garage agreed to do it again without admitting liability provided I prepped it again which I was willing to do. The next job was perfect!

[_dan_]

Just read this with great interest.

I had some bodywork done on the Tiv early last year, and last summer a few blisters developed and popped (about 5 along where the joins are - about 1" wide each). They seemed to grow in the heat.

Does this sound like the same thing as described earlier in the thread?

Also, cause I use the motor as an everyday car (or did till a couple of days ago!) I never got round to getting back to the bodyshop, does anyone reckon they'll still be willing to fix it almost a year and a half later?

Cheers Dan


>> Edited by _dan_ on Thursday 19th May 08:56