Nick Schade recommends using CA to tack welding both hull and deck of his Petrel and Petrel Play.  Picture below shows the deck tack welded with all stitches removed prior to doing filets.  You want to tack weld the inside of the boat so that the filets cover the CA spots.  The CA discolors the wood evr so slightly and may be visible on the outside.

   Thanks so much for the response -- I saw a bit of that discolouration when using CA to tack the puzzle joints, so I will tack on the inside, however I'm still just a bit confused about the process.  I watched a time lapse of a Nick Schade Class building the Petrel S&G and saw that they only mate the deck and hull one time after building each part.

The manual for the Shearwater instructs to mate the deck and hull for a good fit, then take apart and tack with epoxy then immediately mate the top and bottom again while the expoy sets.  If I separate the top and bottom and use CA and Accelerant to tack the seams, do I risk distortion of the parts, since I will not be able to get both halves back together and "set" while together?  Does that make sense?

I guess what I'm asking is - will the top and bottom fit well the second time after I tack with CA?

Sorry for the newbie questions -- I just don't want to end up with a twisted or distorted boat.

Thanks again.

   Hi Dave Your question makes total sense. I have built a regular shear water and simply tacked it with epoxy and then taped everything together to do the best of preserving a deck and hull shape that would mate easily. The epoxy. Because of its long cure time to hardness affords this opportunity in a way that CA can't. CA would be ok in my view if the fit without taping the hull to the deck is very close. Otherwise, just take the extra day to do your tacking with epoxy H

As hspira says, your concern is valid, and there is always a good aurgument for following the manual, especially on a first build.

As you can see from the pictures below, the S&G Petrel & Petrel Play use external forms to hold the hull and deck shapes up through glassing.  IIRC, the SW Double that I built had several internat forms, but I don't know about the SWS.  I did follow the build manual using epoxy tack weld on the SW Double but I do not remeber the deck/hull mating being any easier or harder than ususal.  It seems that part of the build is always a wrestling match regardless of the construction technique.

Your build so your call whuch way to go.  Personally I don't think that it will matter much either way.