Depending on the thickness of the rocker slices, you may end up with something stonger than expected. I've been using foam in widths that allow for half a board, 6" strips, 4" strips, 3" and 2". I've found that more glue lines equals more strength longitudinally, and a little more strength on the surface, but I am seeing more pressure dents in the boards that do not have a veneer deck. More glue lines also means more chance for problems when shaping. Hard glue tends to come off and tear into the softer foam. You need to be careful and watch for that, especially when you get down towards a finished shape. Softer EPS tends to tear out more as well, you need to go slower when you shape and not be agressive with the sanding. If I use a lot of rocker slices to make a blank I like to add a 1" perimeter band of foam to get a cleaner rail shape. Attached photo shows the XPS perimeter band.
I usually glue up the blank pieces then clean up the bottom surface to get a starting point. Then I cut out the outline and get the bottom rocker dialed in. I do the outline early because I prefer to cut through less foam. If I add a veneer skin to the bottom, I'll do it at this time. Now I work off the bottom rocker to get the profile or deck thickness. Once the deck profile is set I'll cut rail bands, then add the first band of perimeter rails if I want them. That will allow me to use less material for the rails, and less to cut through. Then I'll finish the deck contours (crowning) and add the deck skin. After the deck skin is on I clean up the rail, add the last pieces and turn the rails.
Without the perimeter rails, I'll shape the whole board, then add any prelam fin boxes. I do a single layer of glass next. I wrap the bottom like I normally do, but I may only wrap the deck to the rail edge where I tend to have a hard tucked edge. I add the deck veneer with vacuum, and I try my best to cut the veneer to fit what would be a clean deck inlay. After it comes out of the bag, I clean up the edge of the veneer and do a second layer of glass (because I use balsa wood veneers). I'll add my center box and any post lam fin boxes, then I do a second layer of glass on the bottom wrapping around to the top where the deck veneer edge is to lock in the boxes. Fill coat, sand and finish with a thin resin coat, or a floor sealer. After each lam, I'll do whatever cleaning up on the edges before I lam the next layer. I end up with 4 layers of glass around the rails and 2 layers of glass on the bottom, it seems to be good enough.
BB30, masterfully done. Thanks for the seminar.
Question: You say. “forgot to mention I hold the rail pieces together with a 2 " length on 1/8" white or beige masking tape you have in your shop to do pin lins with. It is taped on both sides, in the middle, horizontally as in nose to tail direction NOT floor to ceiling.”
I don’t follow this. Can you set me straight?
All the best
Personally I'm always ready to learn, although I do not always like being taught. - Winston Churchill
Very hard to use words to describe process. my post is confusing to me and I wrote it.
Got down a 6 + footer for example.
If I am using a tail and nose block I will usually get those on first after skinning deck and bottom. Sand them to rail contour
Take four foot balsa blank.
This example I started at tail and try to align the deck to the straight edge to top of plank
Take a carpenters pencil and using my bottom of board for a guide
Score a pencil mark on rail plank
carefully cut pencil score with razor blade
Not trying to get an exact fit but want some over lap of deck and bottom 2-4mm up deck and bottom
This is what it looks like
Now I will get the remainder of rail to nose with the other half of wood I just cut off. It happened to work out this way for this board but will not alway be the case with different length and width boards.
Tape off in a few places to keep down tail section I just cut
Align wood to nose with full coverage of rail and get the angle you need to connec to tail section
Now you take pencil and use bottom as guide and in this case the deck as guide because too much wood was over hanging on deck and bottom side.
I place my arm over the whole plank I ma cutting when by myself. Having a helper is ideal to hold down whilst(word used to make you think I am from australia) you
score plank with pencil.
This is what the marks looked like and the cut, joint and final placment check. Huge over hand on tail and nose because I will have tail and nose block put on before rails are placed.
Label your planks however it will work for you, this is my way.
Now you do the same exact thing but working for nose to tail. Label. Mine would be 2BN or 2BT
Next pick is lines on rail of board where seams will be with an every other plank like I did here. You could make every plank seam not match up it you wanted to take the time to do this or every third plank , etc.
Most rail build outs with 2.5mm thick planks for me are 6 or 8 stacked planks.
Now to answer your tape question Greg.
pics of tail to nose section
taped both sides. tape easily sands off if exposed with sanding. out rail will definately have tape on. Epoxy fills seam and is strong
last pic is me oldin up and wiggling. Imagine 6 of these stacke together getting placed on rail. Super workable and won't fall apart
could have done this with any length of balsa
70 plus year old neighbor scott on a board I made him 13 years ago. shot from last sunday at "Lots".