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What happened to my finish - the answer
By:John Michne
Date: 9/13/2000, 6:58 pm

Hi gang - My post of September 4 regarding the changes in epoxy/varnish finishes on my boats only brought one response. I emailed MAS Epoxies with the same question. Here is their verbatim reply:

In a message dated 9/11/2000 2:13:49 PM Eastern Daylight Time, MASEPOXIES writes:

> J: Yes pro builders have the same problem. What you are experiencing is a very well known phenomina of immaging or printrhrough. This means two thing, one you sevel of finsih and gloss are excelent, and two your boats are aging in a normal fashion and experiencing a slight degree of additional curing. With this slight additional cure comes a minute amount of shrink and thus immaging of the glass especially noticable on a dark very glossy finish. To reduce the immaging the boat needs to be thermally aged prior to final sanding and finish. How to do this is the tough part. Some folks heat (120-130) then cool the part a few times (thermal cycling) just like in real life. In simple terms the next time you sand and refinish the problem will likely dessapear for ever unless the boat is taken to a yet warmer environment (southern floridda and stored in a black bag). The pros tell the owners that their is always going to be some immaging and when they repaint the boat the problem will releave itself. Sorry I can't be of greater help.

Thanks for your question Tony

In spite of the typos, I thought the response was very informative. None of the books I've read on strip building mentions the effect, although it is apparently common. Is this effect only with MAS, or does West , System 3, Raka, etc. have the same problem? I wonder how I could "thermally age" the epoxy without exposing it to sunlight with no UV protection.

I will still build! - John

Messages In This Thread

What happened to my finish - the answer
John Michne -- 9/13/2000, 6:58 pm
Re: What happened to my finish - the answer
David Hanson -- 9/14/2000, 4:01 pm
Re: What happened to my finish - the answer
David Hanson -- 9/14/2000, 4:14 pm
The truth about epoxies
Andreas Albat -- 9/14/2000, 11:46 am
An alternate theory.
Dale Frolander -- 9/13/2000, 10:24 pm
Re:post-curing of epxoy
Andrew Eddy -- 9/13/2000, 9:48 pm
Re: What happened to my finish - the answer
Sam McFadden -- 9/13/2000, 8:13 pm
Thermal Set
Don Beale -- 9/13/2000, 8:05 pm