Lot going on in here…
I went back yesterday & read an old thread of Bert’s called “Latest Creation’s” (if you search exactly that, it’ll come up). Tons of information in there - a lot of which makes way more sense to me now, than it did a year ago ![:slight_smile: :slight_smile:](/images/emoji/twitter/slight_smile.png?v=12)
A few things from that…& to mix into this discussion.
I understand from Bert that the ‘springer’ is only a substitute structural member that allows thinner, lighter boards. In other words, if you use a 2# EPS core, or thicker balsa rails, you don’t get anything out of adding a springer as well. So it may not be the only solution. (Which is complementary to Meecrafty’s ‘more than one way to skin a cat’ contentions.)
If you look at Bert’s boards in the abovementioned thread, you’ll see that the balsa rails are most definitely thin strips, built up & pressed around the perimeter of the board, not chunky pieces, cut to fit. And absolutely not the skins bent around the rails. Bending skins around the rails - I did it on the d-cell board & on the 12’'er with a 1# core - takes out all the flex. The 12’er should be a freaking noodle, with that length, veneer skins, 1# EPS, and only 3" thick, but its not. Its like surfing…well…another homemade Surftech.
So I went home last night & tried out using the offcuts from templating to press on some rail pieces, and goddamn but if it isn’t about a year faster than taping on one layer at a time. I mixed up 8 oz of epoxy, laid out 8 rail pieces (4 per side - just doing the middle 7’ of a 10’ board), brushed on the epoxy (8 oz resin + 2 oz hardener was perfect), and clamped them on with the offcuts, some back-up strips of wood outside the offcuts, and some pipe clamps. No sweat, I can’t believe I used to tape those things.
I also believe there is a lot more going on than EPS, epoxy/glass, and balsa with Bert’s boards. In that same thread, someone asks what are they. He says something to the effect of, “Lightweight foam, balsa skins, epoxy resin & fiberglass, some other fabrics and bits of foam…”
I wouldn’t even be surprised if the deck were a double sandwich - say glass/corecell/glass/balsa/glass. Bert also states a preference for corecell over divinycell because its not as cross-linked & therefore not as stiff (but still good & compression-resistant as a sandwich core). I don’t think he would have bothered with that if there wasn’t any in his boards.
The photo of the broken board shows the springer imbedded in the blank, not routed into the top. The foam above looks a little different - that could be the corecell there so the springer can push downwards into the EPS below easier than upwards into the deck…I dunno (sorry Meecrafty, I’m conjecturing again
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Anyway, go back & read that thread again & look at the dozens of photos of boards. My analysis, based on this thread, the rail one, the vac bag one, and the creation’s one, is that a) there’s more than one way to skin a cat; and b) there’s more to these things than EPS, epoxy/glass, and balsa…