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exterior skin butt joint sealing help

PostPosted: Tue Jan 24, 2006 3:05 pm
by clems
I am concerned with the possibility of the exterior skin 1/4 plywood butt joints leaking. Keep in mind that under each joint is 1 1x4 pine frame where the skin is glued either with titebond II or gorilla, and I plan to put a spruce trim over each joint and screw it down.

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What is the best bet to seal this crack (its flush on the other end, just 3/16" wide at one end? I have thought about a 2 inch strip of fiberglass tape, but I am not that fond of using fiberglass. I searched the forum last night and found several people using a PL adhesive/sealer product applied with a caulk gun. I googled this product and read some boat building articles where this type product was used.

I am looking for suggestions to fill these gaps (to help keep out water) and perhaps a material to seal the trim wood over these gaps before I coat the exterior with 8 coats of minwax clear shield (UV inhibited). My main concern is on the top where water may stand on the flat portions for a small length of time, before evaporating or blowing off.

Lee

PostPosted: Tue Jan 24, 2006 3:12 pm
by toypusher
I would suggest the PL caulk under the strips. Don't put it on until you are ready to fasten down the strips that will cover it. It will seal the joint and still remain flexible, therefore not cracking. I would not overdo it with the PL, just enough to fill the gap and a very small amount to seep out under the strips. If you are not painting or staining (I don't think that stain with work on PL caulk) then you have to be careful not to have it showing. This is just my opinion!

PostPosted: Tue Jan 24, 2006 3:26 pm
by EZ
A good method of sealing an area like that is to take epoxy and mix it with talc (may favorite), micro-balloons or wood flour (fine sawdust) into a paste and fill it in with a putty knife. The stuff dries hard and sandable and bonds as well as waterproofs. If you are painting you could sand it down to invisible. However if you are going to put a strip over it anyway maybe some caulk is a lot easier.

EZ

PostPosted: Tue Jan 24, 2006 4:42 pm
by madjack
...both of the above sound good to me...I think I would go with the PL caulk and use it like Kerry suggests...it is good to see someone going with the ClearSheild...on the "next" build, we plan on doing a woodie and are going to use that same product...anxious to know how it worked out
madjack 8)

PostPosted: Tue Jan 24, 2006 4:53 pm
by Mightydog
Where else but this forum could you find a headline like that?

PostPosted: Tue Jan 24, 2006 7:37 pm
by clems
I would suggest the PL caulk under the strips. Don't put it on until you are ready to fasten down the strips that will cover it. It will seal the joint and still remain flexible, therefore not cracking. I would not overdo it with the PL, just enough to fill the gap and a very small amount to seep out under the strips. If you are not painting or staining (I don't think that stain with work on PL caulk) then you have to be careful not to have it showing. This is just my opinion!


Thanks for the replies, I thought about what you said Kerry, but wonder if the PL caulk would stick to wood already stained? I read your intent that the stain wouldn't stick to PL caulked areas. What do you think about the PL sticking to the stained wood?

Lee

PostPosted: Tue Jan 24, 2006 7:49 pm
by toypusher
Lee,

It should stick just fine. I intent there was that PL is colored and would show. No what you want when you have a nice stain.