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Re: Material: Adhesive for Minicell
By:Paul G. Jacobson
Date: 3/15/2011, 3:22 am
In Response To: Material: Adhesive for Minicell (mtkayak (Mike Trutwin))

: Been looking back through the archives but still a little unsure. I
: am gluing a 1/2" minicell pad to my wood backband. The
: backband is coated with varnish and sanded for some bite. I've
: seen 3M Super 77, contact cement, and Household Goop...what's
: the best?

What do you have on hand? This will probably get a lot of abuse from squirming, and need to be replaced every few years. If you have the materials on hand now, make several parts to the correct size now, and keep them on had for quick replacements. You can use any of the 3 glues you mentioned as a contact cement--and you need a contact cement of some kind. If you use a "wet" glue the solvents in it will never evaporate and let the glue thicken. They'll be trapped between the glassed plywood and the closed-cell foam. With ny contact cement all the solvents evaporate, leaving behind a layer of glue. Slap two pieces together and the glue on one will grab the glue on the other and it si bonded until the parts fail.

: Also gluing in varnished wood bulkheads. I have spot glued them in
: with hot melt glue with an 1/8" gap or so. I planned on
: using silicon to finish up but read that's a bad idea so now
: thinking 3m5200. I don't like the idea of white sealant but I
: hear it comes in black too, but harder to find. Would rather it
: be clear but I could live with black. Is this the right product
: for the job?

I second Hamm's views. Glass the seams. The drops of hot melt glue will hold the bulkheads in place, but leave a bit of air around them That is important so they don't constantly press against the sides of the boat and create "stress risers", or areas along the hull where stresses can concentrate, and lead to breakage. You can use short pieces of glass cloth cut into 2" wide strips. Wet them out and press them into place. You don't want to put in a solid fillet under the glass, or over it. Leave your seams flexible. You want the bulkhead to float a bit. Under pressure the bulkhead can shift a small amount.

If the area behind the bulkhead is sealed tightly you can get problems with airpressure changes during a day. Drill a 1/8" hole hole in the middle of your bulkhead and cover that thickly with epxoy. It is fine if it fills in. Drill a fresh 1/16th" hole in the middle of this plastic dot so pressure will not build up. You won't get water inside through such a small hole, but you amy be able to hear the air whistle through it.

PGJ

Messages In This Thread

Material: Adhesive for Minicell
mtkayak (Mike Trutwin) -- 3/14/2011, 5:39 pm
Re: Material: Adhesive for Minicell
Joe Whitman -- 3/14/2011, 6:01 pm
Re: Material: Adhesive for Minicell
Don Goss -- 3/14/2011, 7:30 pm
Re: Material: Adhesive for Minicell
Bill Hamm -- 3/15/2011, 12:56 am
Re: Material: Adhesive for Minicell
Paul G. Jacobson -- 3/15/2011, 3:22 am
Re: Material: Adhesive for Minicell
Mike Bielski -- 3/15/2011, 8:22 am