Thanks Chris!
One thing that caught me my last cutting session this weekend is the blank ends. The templates need to be a bit longer, like 2" (5cm) each end to account for the ‘hysteresis’ or delay in the curve of the wire by hand. I made templates with cute little 1" (2.5cm) ‘shelves’, which I replaced on the fly with 2-3" (5-8cm) scrap strips and hot melt glue ran at a tangent to the curve in process.
Hi JRandy
Can you confirm something about the foam.
So you buy plain insulation polystyrene EPS foam from a foam or building company in sheets of a certain thickness (my options are 100mm, 125mm, 150mm) in a certain grade (density) of foam (my options are what the foam company refers to as Medium in 18 kg/M3 or Hard in 24 kg/M3).
How does it go sanding and making the rails and contours on the bottom. Is it easy to work with. Do you use a EPS foam sealer before glassing. How is its bonding with the glassing/fibreglass. Are you using what I would define as: ‘high quality epoxy resin’ or ‘specific surfboard epoxy resin’ or ‘just any epoxy resin you can find’.
Are you then inputting your own wooden stringer: I have found a very nice marine grade plywood to source.
How heavy are you glassing.
Regards
@Chris4
I have bought EPS in densities 0.88PCF (14kg/m^3 ‘soft’ ) and 1.5PCF (24kg/m^3 ‘hard’ ).
The lighter one was an approx 150mm sheet, the heavier one was a large block 0.7 x 1.2 x 3+ meters (2x4x12 feet).
The heavier foam was easier to shape and sand and more resistant to dents in the shaping bay, which sometimes can be steamed out with a clothes iron and a damp rag.
I have never done a PU blank so I cannot compare to that. Some folks use an even heavier 2PCF foam and the ‘fused’ varieties should afford less bead tearout.
I used lightweight spackle before glassing. I don’t think (it’s been a few years) I liked the one that I added extra acrylic via floor polish to the spackle.
I have added stringers, have yet to try marine ply. I now have access to a nice bandsaw with a resaw blade so I may go old-school on the next one.
Here is my last ‘build’ thread (2015, has it been that long?) with glassing notes on the last page:
I would lean towards surf-specific epoxy to get the viscosity and brighteners and reasonable flip times. My last Ebay batch of epoxy had a three day flip time (hard enough to sand) where surf blends are measured in hours not days. Better materials do make a difference, including glass cloth and sandpaper.
Don’t consider my advice to be the end-all, there are way more experienced people here that have taught me most of what I know.
