Shrinkage -> Hey fiberglass experts [Archive]

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Tom Brown

05-24-2005, 11:23 AM

I'm about to make a plug for a piece that needs to fit snuggly over another piece. It's like the lid of a shoebox... at least, around the edges.
I need it to be pretty accurate (within about 1/8"). The piece is 24 x 15 inches.
How much shrinkage can I expect using polyester resin? I'd like to know how much to oversize the plug so the final piece will fit decently after the mold and part shrinkage.
Thanks. :)

Nord

05-24-2005, 11:25 AM

Tom Brown has shrinkage!! :rollside:
P.M. BadBlown572

Tom Brown

06-10-2005, 08:59 AM

bump

Dave C

06-10-2005, 09:06 AM

shrinkage jerry, tell them about shrinkage.....

ratso

06-10-2005, 09:57 AM

Tom, if you have a plug or mold and let it sit up, there shouldn't really be any shrinkage. You might have some sanding to do for a perfect fit though...

CandyA$$

06-10-2005, 10:03 AM

Fiberglass does not shrink. Where did you get that idea?
If that were true then our boats would fall apart.lol

CrazyHippy

06-10-2005, 10:27 AM

Fiberglass does not shrink. Where did you get that idea?
If that were true then our boats would fall apart.lol
Your'e kidding right :confused:
BJH

CandyA$$

06-10-2005, 10:34 AM

Oh my gosh I am not the blonde. Oh wait I do have blonde in my hair. Oh Oh no I am good.
LOL!

Dave C

06-10-2005, 10:38 AM

but what about in really really cold water? no? ;)
Fiberglass does not shrink. Where did you get that idea?
If that were true then our boats would fall apart.lol

moneypit

06-10-2005, 10:39 AM

ALL FIBERGLASS SHRINKS. The larger the lay up, the more shrinkage. ( I wrote that... but I read it first) :D

C-2

06-10-2005, 10:45 AM

There's a guy on this board named Jeff from Smooth as Glass in Modesto, he goes by washedashore on here, but doesn't post much. He'll be able to answer your question, try him at (209) 869-3545. Tell him you're from the board and that Craig from the poker run sent ya. People say he does some sick ass stuff!

Tom Brown

06-10-2005, 11:40 AM

Thanks, everyone. :cool:
Yes, even you Dave. :D

ratso

06-10-2005, 11:45 AM

...something that small CAN'T shrink too much, uh... the box that is. :idea:

CandyA$$

06-10-2005, 11:50 AM

but what about in really really cold water? no? ;)
Well Depends on how hard it has gotten. If sticky maybe?
LOL

HOSS

06-10-2005, 11:55 AM

Well Depends on how hard it has gotten. If sticky maybe?
LOL
The amount of shrinkage you`ll experience will be minimal. In other words build to size. Thats it! Glass is easy to use wet and a wee bit harder to sand. Do the job right one time to save time.