Re: 1960's 13' MFG carefree Rebuild (complete noob, i know nothing about this!)
.. Hmmmmm,.... Jon sob says his transom was 1.5 inches originally, maybe ill add another piece of plywood and make it 4 pieces for the transom. That would be pretty strong. What do you mean by it will leave me 3/8 for laminating
When you laminate the 3pcs of ply together, at 3/8" per, that's a total of 1 1/8" of total wood in your plywood build up for the transom. If you are trying to hit a total finished thickness of 1 1/2", you've got 3/8" of space available for the PB (or PL) to the transom and however you're gluing the 3pcs of ply to each other. And the layers of glass & resin you'll apply to the plywood on the inside & wrapping the tabbing onto the hull sides.
Does that ^^^ make sense?
Also, how should I glue these pieces together? I. know it needs to be done one at a time, Do I need to use PB or could I just use woodglue to save on poly resin? I understand that using the Peanut butter would require me to glass a piece of csm to each piece of wood. After which I would lay the pb down and put the next piece of wood down. Should csm be glassed to each side of the pieces of plywood? Gosh, I wish I could find woodoglasses pictures, they were so helpful! I miss him too, he always chiimed in and was willing to help
Since you are probably laying these sheets in 1 at a time, this is how I'd do that (Jon will hopefully chime in if he notices any thing amiss):
- Sand/grind the repairs you made to the hull in prep of moving forward, feathering the edges
- Cut the plywood pcs to fit, @ 1/8" gap on both port/starboard sides & to the hull bottom. When clamped into place the ply pcs will get shorter against a curve
- Since the ply is so narrow, it may prove difficult to CSM & resin the edges of the ply before you laminate them to each other
- I'd prep the transom skin that you patched & smoothed/feathered, and cover it w/ thin mil plastic, stuck & taped as best you can to minimize it's thickness, and prevent accidentally gluing the plywood into place
- Take the 1st pc of ply and cover the interior face w/ either PL or TiteBond3 glue, making sure to cover it well, with a thin layer of glue (a notched trowel would work w/ either) set the wood into place against the transom skin
- Quickly coat the next pc of ply with PL of TB3 (only the inside face, the side facing the bow) and place it against the 1st pc of ply
- Take the last pc of ply and sandwich it against the 2nd pc of ply
- Use the WOG clamps to secure the 3 pcs of ply against the exterior transom skin
EDIT: Please note that these steps, from start to finsih, need to be completed fairly quickly, before the glue between ply sheets starts to set up. And that surface tension of the glue may make it difficult to adjust the 3pcs of ply to align properly once they are stuck to 1 another. To ensure there are no air pockets or voids in the glue layers, relief holes can be drilled thru each sheet prior to starting the layup, 1/4"-3/8" would probably be sufficient. Then once all 3 pcs are cured to shape, a 3/8" - 1/2" hole can be drilled thru all 3 sheets to allow the PB or PL to key into the transom wood & help keep it well stuck to the transom skin....
Once the ply laminations cure in a curve shape, you can take them out of the clamps, clean up the excess glue and remove them from the hull. Although it now has a slight curve, the 1 pc transom can now be prepped & finished as a 'normal' transom. With the curve, the ply edges of each pc will not be even. If you can, you might trim them to flush so you can more easily CSM & resin the edge. Prep & CSM the back & front of the new single pc plywood transom.
Once that CSM is done on the edges & faces, scuff the back side of the transom plywood lamination. Acetone clean it & the transom skin that was prepped previously, then apply PB or PL. Set the plywood into place and clamp again.
Use enough, but not so much pressure to over squeeze the PL or PB out of the joint. Just enough to securely bed the wood into your PB or PL.
There should be a little squeeze out. If you've used PB, take a large kitchen spoon (I HIGHLY RECOMMEND A METAL SPOON FROM THE DOLLAR STORE, NOT THE KITCHEN) and create a cove, curved transition between your transom ply & both of the boats sides & the bottom hull.
PL used between the plywood pcs will take 24+/-hrs to cure. Maybe longer. PL used between the plywood lamination & your transom skin will take at least as long, probably longer. You will want to wait at least 72 hours before using ANY poly resin anywhere near where you've used PL.
Tab, CSM/1708 the newly installed transom wood to the hull
Jon's version is somewhat more brief:facepalm: But no less accurate
