Let me amplify Neira’s reply a little, if I may and if I’m understanding his methods correctly;
Quote:
I have a longboard broken but no completely snapped. The stringer is broken but the top glass is intact. I was going to trim the ends of the stringer to clean then up. Then use a small circular saw to cut away next to the stringer to add a couple pieces of wood as in this thread.
Couple questions about repairs:
- Cut away de-lamed fiberglass correct?
- How did you make your jig to reset the rocker?
- Tint the resin to match the yellowing of the board?
- Resin tint competition stripe to hide the snap, just sand down gloss coat, then re gloss when done?
Thanks guys, this is a great thread. I even saved it to a word document. I wish there was a seperate section for repairs, will be doing more of that than shaping.
and
Quote:
Deck glass does NOTHING for strenght. Which is important for board strength are the “vertical” layers of fibregalss that overlap at the rails.
So:
-cut deck glass and get 2 separate pieces
-clean wax from the whole board
-cut loose fibregalss from all the edges
-sand stringer edges so they won’t touch when joining
-cut 2 slots ,using a handsaw, on each piece
Why doing a resin tint for the competition stripe when it’s easier to lam a solid color cloth band??
Okay - the thing about attempting to keep the top glass is this; it’s loose and messed up in the immediate vicinity of the break, so it’s just gonna have to be sanded away at some stage, better to cut it now rather than later- it will make the whole procss easier.
The rocker jig, as it were, can be eliminated if you’re using Neira’s method. The wee bits of wood right alongside the stringer are the jig, they are tight enough so that they act like scissors or such in slightly undersized ( width-wise - a skosh bigger than the saw kerf) slots. Rather than using a circular saw, use a handsaw, that way the stringer will force it to go the right way, be nice and straight, etc. They will line up right, it’s a really smart way to do it.
A circular saw will make its own path, not necessarily straight, which will likely require large chunks of wood and a lot of filler. Not a good thing, just the opposite. And I have been working with hand-held circular saws for in excess of 30 years and am quite good with 'em, I don’t think I could get it right even with my favorite old Rockwells, which are to my mind far better than anything built today.
Bear in mind that the wood is being added to act as a rocker jig and to line up the pieces as locating pins not for structural reinforcement. That’s where added glass comes in, that’s the strength.
Tinting the resin - if the foam has yellowed, you’re kinda stuck with it, cos the glass is gonna be clear and the foam filler you use will be a slightly different color. I have used a number of things, including instant coffee, to match the yellowed ( actually a light brown) area, but the thing is the delammed glass you will be cutting away is the problem here. See, whereyou cut away glass, it usually takes some foam with it, and you will have to inlay something to make up that thickness. Neira is using glass mat, which is a good idea; it winds up about the same thickness as the cloth plus the thin skin of foam that was there. But…if you try to tint that, you’ll have problems with appearance.
Anyhow- after you’re done with this, the surface should be relatively smooth and flush with the original glass.
Then you can either lay on some fabric, as Neira suggests, to hide the area ( especially if there’s a long area of the old glass torn away and then filled with mat inlay) or ( as this sounds like a narrow, clean break ) do a colored/pigmented lamination, skipping the fabric step.
Now, I would look carefully and see what it will need. I’d use two bands of cloth each side, on a longboard I would go 6 oz or better ( which is probably overkill, but I like overkill ) , first band maybe 10-12 inches wide ( 25-30 cm ) and the next band twice that width, both centered on the break and well lapped around the rails. This is important, it’s what gives the repair its strength. I like two bands of cloth each side because it makes the stiffness change gradually, no abrupt transitions, so that you don’t get a line for it to break along where the stiffness abruptly changes. Then hotcoat, then gloss. You only want to color one of those laminations, not two. I’d pick the first, narrower one, but that’s me, you may want to do it the other way round.
Then hotcoat, then gloss and polish as need be.
While writing this I reread the whole thread, and I have to say I come away even more impressed with Neira’s methods here. Well thought out, a complete and clear understanding of the structures involved and most of all a familiarity with tools and materials and how to use 'em.
My own question; is that a ripsaw or a crosscut saw used in cutting the slots? The tooth profile ( ||||\ rather than ////\ ) looks like a ripsaw, but I figure it’s best to ask-
Best regards
doc…