Thanks for the welcome chip...
And it is a purdy boat!

I don't think I would try to bag the exterior of a boat still on forms. The bag has to have a really good seal, or leakage will prevent getting a decent vacuum. The pumps are low volume. In order to get a good enuf seal, I think you would need a full poly layer INSIDE the boat extending beyond the gunwale to seal the exterior bag to. Without it, you would have leaks through the hull, pinholes, voids between strips, possibly even through the pores of the wood. Its a lot of area to seal. Maybe, if planning way ahead, you could build over a full poly sheet over the forms... Beyond all that, you have to add fill coats on the exterior anyway. Adding fill coats kinda defeats a lot of the purpose of using a vacuum bag to squeeze out all the excess! The bag will minimize epoxy UNDER the glass, and ensure thorough saturation IN the glass (assuming you put enough resin ON), but the fill coats still must go on the outside. To me, the REAL benefit comes on the interior of a decked kayak, where you can bag it, and then NOT fill it (except for possibly a very thin coating to seal any pinholes, a step which MAY not be necessary with vac-bagging). And, on the interior, you have the exterior glass already on, so an exterior bag is not necessary. I think (disclaimer) you could just wrap the poly bag around the edge and tape it to the cured glass on the exterior.

I haven't begun building a yak. But I do aspire to ... and daydream about it.
Really the only thing stopping me, is the large volume epoxy use. I have an autoimmune illness, and fear that the inhaled chemicals may trigger an unwanted immune response/activity... Its pretty near killed me several times (the illness, not epoxy) so I am careful to the point of paranoid about not aggravating my immune system. In fact, I haven't built any RC planes in a while either...