Woodie Hatch separation

[Alan and Lianna]

On my hatch, I have 1/8 inch baltic birch with 6.5 oz fiberglass cloth (right side of pictures), after sanding the sides smooth and epoxying it with several coats of epoxy and glueing it down with tightbond 3 it looks like it has shrunk and separated on the edges. Is this to be expected and needs to be covered with trim? or do I have other options?




Alan and Lianna

[Miriam C.]

Your pictures are wonderful but so close up I can't tell what I am looking at. Any chance of getting a bit further away?

[afreegreek]

you tried to glue components together with TB-3 after they were coated with epoxy??

[Alan and Lianna]

No, it was glued first. It appears as though the 5 foot birch ply shrunk approx 1/8th inch after being glued and epoxied and 3 weeks in the sun.

Alan

[afreegreek]

No, it was glued first. It appears as though the 5 foot birch ply shrunk approx 1/8th inch after being glued and epoxied and 3 weeks in the sun.

Alan

I suspect you took too long to assemble the parts and the glue didn't bond well.. it's almost impossible for a glue line to give out like that.. you should have had fibre separation as a good glue bond is stronger than most woods that are not resiny or or oily (rosewood/teak etc)..

if the panel is otherwise sound, an easy fix is to rebate the edge and glue in a corner piece.. say 1/4 x 1/4.. if you do a clean job with the router, it will look perfect..

[kennyrayandersen]

No, it was glued first. It appears as though the 5 foot birch ply shrunk approx 1/8th inch after being glued and epoxied and 3 weeks in the sun.

Alan

I suspect you took too long to assemble the parts and the glue didn't bond well.. it's almost impossible for a glue line to give out like that.. you should have had fibre separation as a good glue bond is stronger than most woods that are not resiny or or oily (rosewood/teak etc)..

if the panel is otherwise sound, an easy fix is to rebate the edge and glue in a corner piece.. say 1/4 x 1/4.. if you do a clean job with the router, it will look perfect..

been there -- done that -- it should work good
1

[Larry C]

On my hatch, I have 1/8 inch baltic birch with 6.5 oz fiberglass cloth (right side of pictures), after sanding the sides smooth and epoxying it with several coats of epoxy and glueing it down with tightbond 3 it looks like it has shrunk and separated on the edges. Is this to be expected and needs to be covered with trim? or do I have other options?




Alan and Lianna

You could, after filling the gap, cover the entire edge with 2-3" wide bias cut strips of fiberglass. Something in the 3-4oz. range would bend over the corner easily, especially if you break the edge a little.

If you left the unprotected fiberglass/epoxy exposed to UV from the sun, you may have more problems down the road, especially if your leaving the wood bright. The sun actually may have shrunk the fiberglass and that's what pulled the edge. Can you see glass print thru? This is an indication of shrinkage.

One more thought is the Titebond 3. At what temp does it soften? Titebond 2 softens in the sun and any glue bond under tension can be a problem even under fiberglass. This can be a problem on the decks of strip built kayaks when using dark wood strips.

$.02

Larry C.

[kennyrayandersen]

One more thought is the Titebond 3. At what temp does it soften? Titebond 2 softens in the sun and any glue bond under tension can be a problem even under fiberglass. This can be a problem on the decks of strip built kayaks when using dark wood strips.
$.02
Larry C.

That’s a good tidbit to know [that I didn’t know before]. Actually, it makes sense since epoxy also gets less strong at elevated temperatures. Stuff sitting in the sun can get pretty hot – especially if painted a dark sun-absorbing color!

[michaelwpayton]

... If you left the unprotected fiberglass/epoxy exposed to UV from the sun, you may have more problems down the road, especially if your leaving the wood bright.

Epoxy MUST be UV protected.

[glassice]

It's look like the glass did not pop you might have something expanding in side is there some wood on the inside that got bigger in the heat if so cut a re leaf at the end and re glue