so I got me some EPS and balsa sheet...

[diggerdickson]

I wouldnt sell it so fast dUg.....make a rocker jig from the original board you copied and see if the new one matches.....check everything you can......there's something to learn from it...

Dug, that so sucks, thanks for the candid report mate, a bit disheartening for all of us, but please please dont give up, I like what kayu said and check it all out to see if you can find what went wrong, im interested for sure, compare rails rocker, measure as much as you can, would be interesting to know if you spotted anything.

Worse case is that it could make a great wall hanging.

[tiger]

Hey dUg. Funny ride report .

Mate you did a great job on this build, I feel you may not have paid enough attention to the most important part of the board, the rocker. Easy to do when there is so many other components and buggerising around with this type of build technique.

I hadn't commented on the end product, because I couldn't think of a nice way to tell you the rocker appeared a bit woofy. But looks like you found out anyway.

Make a rocker bed of sorts. I love my rocker table, it is the most awesome thing I've ever made. But there's no need to go that far, there's much easier temporary options.

You've shown that you have a handle on the material side of it, put a bit more energy into the mechanics of it. Hotwiring, bagging, rocker bed etc are your friend. The concept of them seem difficult, but starting something is the hardest part. Dive in, waters warmer than you think.

[dUg]

I hear ya all on the rocker table, and I kinda knew that was always gonna be a bit of an unknown quantity.

I must admit early doubts surfaced when I took that first pic of the board just after I cut out the planshape, and sat it flat on the concrete. I suspected there and then I may have over-rockered it, but I think the bigger problem was that I bent in a continuous rocker with no discernible planing area. I knew this was a risk from the outset, but I hoped I could fine tune it by taking meat off the thicker bottom skin. The problem was that the high point was too much to take off ( e.g. > 5mm ) and worse, I attempted to fix it with a single concave. I think even if I managed to plane out enough through the middle there still would have been too much curve in the rails. I was unsure how much the board would "spring back" after I took the weight off it, and I definitely overestimated that. But surely this effects a rocker bed as well if you exactly copy the rocker of an existing board? I'd expect it to come off the bed slightly flatter than the curve in the bed itself... but maybe I am missing something. :?

The thing is I have made three conventional EPS blanks using continuous curve rocker, with a 3-ply stringer. All of those boards went really well ( even if they looked awful ), including the infamous Epoxy Carbo Rail Flyer. That board had at least as much rocker as the compsand... and I botched the FCS plugs... and it was two inches longer... yet it never suffered the horrible drag I felt from this latest failure. If I could see a really big difference I could say to myself "ahhh.. you really fucked up there, dug", but the thing is... I can't see anything that looks disastrous. And that makes heading back into the shed a bit daunting, to be honest.

Right now, I have decided to try something desperate. I've turned the bitch upside down, sat it on foam blocks, and positioned 20kg of weight just aft of the mid point. I measured the height above the floor, and I'll measure it again in a few days. In theory, if I leave it weighted long enough, it will at least take some of the rocker out.

The more extreme approach is to get violent with the planer, and take out a shitload more rocker. I'd also destroy the concave and revert it to a flat bottom. You can imagine what's involved here: sanding off the glass and bottom skin ... followed by re-skinning, re-glassing, and trying to make it not look like an epic train wreck. It would take hours, it would cock up the foil completely, and would still carry a high risk of ending in spectacular failure.

I'll measure it again on the weekend and see if it's helped. If not, I might try parking my wife's car on it for a few days.

[diggerdickson]

Dug, I just want to let you know that once, when I finsihed a shape, gave her a great little spray, hand prints of my kids all over the deck, I then took it to the shed to laminate, blocked out all the uv light, preped my resin then got my missus to lock the shed door. The only bloody problem was I forget to set up a light, my missus went out, it was bloody dark, Im stuck in the shed, with glass on the board ready to go, bucket of uv in hand and I cant see a bloody thing So I glassed the bitch anyway, the fuckup fairy loved me that day. An hour of so later my missus lets me out of the shed, I had the shits with myself so badly that I took the blank out in the sun, let is cure then lamed the other side.

Ive never filler coated the board, no bloody point, I butchered her by that one foolish mistake. I am keeping the laminated board as a memory of what not to do for myself. I use it for motivation to get the small things done right if I can.

I hope mate you can find some motivation out of this, or at least you had a lot of enjoyment making something, more than I can say for most who will never give something like this a go.

[tiger]

You may be able to flatten it a bit with weight over time. Don't know if it will slowly spring back or not, an interesting little experiment in itself.

R.E. the springing back of the rocker. Once both skins are on, the board is rigid. I do the bottom skins and rails in the first bagging process. Then the deck in the second bagging process. Both on the rocker bed.

Have you read the thread on Swaylocks by Bert Berger, Vaccum forming and sandwich construction? It is all laid bare there in practical terms, unfortunately I don't think a lot of the pics are still on it. Regardless it is essential reading.

[dUg]

You may be able to flatten it a bit with weight over time. Don't know if it will slowly spring back or not, an interesting little experiment in itself.

R.E. the springing back of the rocker. Once both skins are on, the board is rigid. I do the bottom skins and rails in the first bagging process. Then the deck in the second bagging process. Both on the rocker bed.

Have you read the thread on Swaylocks by Bert Berger, Vaccum forming and sandwich construction? It is all laid bare there in practical terms, unfortunately I don't think a lot of the pics are still on it. Regardless it is essential reading.

It took some digging but yes Tiger, I found Bert's old thread... and yes... realised I'd read a lot of it about 3 years ago when I first began kicking around the idea of no-bed no-bag compsand construction ( I call it NBNBC ).

I've had weight on the sucker for a fortnight now - 30kg - and it has compressed maybe 1mm. Fark... these things are tough, eh? :O

I'd have to say I'm not overly hopeful, but today I am clamping it to a lump of 6 x 2" window frame timber and just leaving it for a while to see what happens. I'll also router out the fin plugs and re-set them because I'm pretty sure that's not helping a whole lot.

I won't keep it, but if i can at least improve it to the point it's somewhere above unsurfable, I'll feel less guilty flogging it on ebay.

[kayu]

Just a thought dUg....if you sand down to weave on the bottom and rails, then peel of the glass , you could plane of the bottom timber.... this should relieve enough tension pull it into the curve you want, so you can laminate on a new bottom skin.....maybe

[ric_vidal]

dUg, sorry mate but that was a funny read. Lucky you have the patent on the Epoxy Carbo Rail Flyer!

Mate, don’t try and resurrect, sell, give or throw the f*cker away and move onto your next one.

Too much of an elbow in the bottom by the look of things, we’ve all been there I suspect.

[diggerdickson]

dug, this has been an awesome read, really mate, as one day I want to head in this direction, thanks for the honesty and frankness on how you screwed up mate. Your gonna have to try again one day, cant wait for the build on that one either

[Beerfan]

Dug, swap the fins for MR twinny's, with no centre fin and see if it makes a difference. Maybe a fin issue?? Seems like you know what it is already, but maybe some completely different fins might make it go better for you??, or at least compensate??.

Nothing worse than going to all that trouble, then being disappointed

[ric_vidal]

Anyway I went back an measured the few good boards I fluked and yep there rockers all fell within in the 12 inch guide (pure luck )

I'd be less concerned with those numbers than the bit in between, Saltman, as I think that is where the problem lies for dUg.

[dUg]

Thanks folks for your interest in this, I have been a fair bit sidetracked the last few months with work so haven't had the luxury of checking RS much. I hadn't actually deserted my post.

Aaaaaaanyway... some of you will be amazed ( or mystified ) to learn that I have actually ventured back into the shed only recently, and I'm about halfway through a second compsand. I have been taking things VERY slowly, just doing a bit here and there, but it's taking shape and of course, benefiting from lessons learnt with the first one.

This new board is not for me, it's actually for a good mate... a belated 40th birthday present AND an apology. He actually had his birthday AND wedding last year, ON THE SAME DAY. I was crook in the days before and spent the actual day in bed - but didn't even realise until a week later I was so out of it. I was about to go out and get him a present on the Friday thinking it was the following weekend ... then I looked at the invitiation. FFFFFFFFUUUUUUUUUCCCCCCCCCCCCCCCCCCCCCKKKKKKKKKKKK!

There's an extra element, in that said mate is my former shaper - he's made me about 6 boards in all and they were all excellent. He's given up now, so I thought it would be a really novel thing to do to make a board FOR HIM, as I doubt any other of his mates would posess the patience / ability / insanity to give it a go.

I'm well aware that it's probably gonna be a bit like one of those paintings people's kids bring home from school, where they say proudly, "it's a horse", and it just looks like a random bit of scribbling with food stains all over it, but it still goes up on the fridge door for 3 years.

That's the sort of thing I'm going for here.