I have an old sailboat with a vacuumed formed plastic hull and deck. The original builder used a type of glue that has failed. I succeeded in removing the deck from the hull with no damage to either. I'm now in need of some advice regarding the the type of glue to use for rebonding the hull and deck. Any advice would be appreciated.

What would be wrong with using epoxy?
- 'Doc

See if you can get hold of some Ethyl-Acetate (chemist), it's a solvent for ABS and will weld it together.

Try on a spot out of sight if it solves your plastic and make a test weld.

Don't spill it on the rest of the hull.

I use it on all ABS joints and it works very well, nothing ever comes loose again.

Let it air out completely, otherwise you'll end up with weak spots.(don't ask...)

Regards, Jan.

I very much appreciate the suggestions, however, I should have elaborated on the problem a bit more. There is a 1/4" square piece of balsa wood that is still very securely bonded to the hull at the top edge of the hull. The was was bonded to the balsa using what appears to be a somewhat flexible glue that easily peals off the deck. It is a semi-clear yellowish material that when sanded still gums up the sandpaper. Does anyone know what type of glue this is? Is there an epoxy that remains flexible after 10 years? I'm in the process of completely removing this material from the top surface of the balsa (to which it has bonded very well) since I don't believe I can find a material that will bond to it and the vacumed formed plastic (ABS?) deck. What I need is a material that will bond balsa to the plastic deck. Any further suggestions would be appreciated.

I'd suggest a one compuonent contact glue, don't know US brand names, over here Pattex and Bisontix are two.

BTW, if the ABS deck and hull have contact, the solvent method will work. (if the solvent works on your plastic...)

Regards, Jan.

Thanks for your suggestion. I had not considered contact cement. I'll add it to my trials. Currently, I have adhesion tested Ambroid glue, Fabric glue, epoxy and 3M 5200 marine sealer/adhesive. I've been testing the adhesion of each of the above using a small piece of fiberglass placed on the underside of the deck. Currently, the best adhesion appears to be the Fabric glue. I have not tested the 3M material as yet due to long cure time for this material. There is not enough surface contact area to bond the hull and deck directly. The 1/4" balsa must be bonded to the ABS deck.

I've no idea what your glue may be, but if/when you find out, I think I'd like to have some of it (LOL).
All glues 'dry out' or get brittle over time. Epoxy glues tend to 'turn loose' when heat is applied (pray the melting temperature of the two things it sticks together is higher than the epoxy's melting point!). The 'mek' type glues don't 'dry out' since they actually 'melt' the two surfaces together (plastic), but it's problem is that the joint tends to shrink over time, causing a weak spot. That time period isn't a problem in most cases, but it does happen.
- 'Doc

(This is strictly a personal observation so take it for what it's worth.) My models have a limited life span. Either because I do something 'dumb' and break them, or because I loose interest in them. So, almost any glue will last as long as the model does. You have a choice when selecting a glue, ease of use or longevity (among other considerations). I look for a reasonable 'life span' from glue, and since I'm lazy I want an 'easy/fast' glue to use. The two are not always compatible. So for me, the definition of 'reasonable' is variable. You 'pays your money and takes your choice'...

If any two parts of your aba hull are in contact use methyl ethyl ketone. It will weld plastic and it's permanent. I used it on two Soling 1M's. Works great. Be sure you have some sort of mask. The fumes are harmful if inhaled. Even so you can buy the stuff at ACE hardware. Just place the two parts together and wick it into the joint. It will be solid in about 10 minutes or less. If the only contact you have is wood, 45 minute epoxy is available and will hold together after all else fails. Be sure to roughen the plastic to give the epoxy something to grip.

Thanks for the suggestions. Unfortunately there is only an edge of the hull ( material thickness only) that will make contact with the deck. I think your suggestion of using epoy is what I'll end up using.

Material thickness is all Methyl Ethyl Ketone and Ethyl Acetate needs. Just apply moderately, in order not to melt anything.

Regards, Jan.