Brian,
If your tiller is delaminating, I would suggest pulling it apart where you can and inspect for dry rot. The lighter wood (ash) tends to dry rot soonest. I had this experience with my Ericson 25. If it isn't dry rotted and you decide to use epoxy (which I think is a good choice), consider the following:
Do you have experience with epoxies and boats? This may come across and too basic, but we all want you to get good results. At the risk of sounding patronizing, be sure to use plenty of clamps as suggested above, but DO NOT over-tighten and squeeze all the epoxy out of the seems, cracks, and joints. Epoxy does better making stronger bonds if it isn't all squeezed out. Also, epoxy (at least the WEST epoxies) migrate very well if they haven't been thickened with fibers or colloidal material. Allow the seams and cracks to remain open for a few minutes while reapply additional liquid in areas soaking it up until you get really good saturation before clamping. If you can vacuum bag, this is even better. Keep very strict control of your portions, mix thoroughly and ensure your temperatures are exact. You might make a bit of a mess, use disposable gloves, protect your clamps with plastic bags or something similar to keep them clean and not sticking, then expect to do some sanding when epoxy has set. Once the epoxy "kicks" you have be be done.
Also, remember, epoxy has no UV blocking. Anything exposed to the sun will deteriorate over time. Use at least a couple coats of exterior varnish to coat any epoxy exposed to daylight. Good luck. This was a fun project for me, you'll enjoy it, too! Let us know how it works out.
