I’m totally new to shaping and glassing. My plan is to make a mold out of one of my surfboards and fill it with polyurethane to get a replica blank to start off from. I’ll only do minor changes to start with as I know nothing about shaping what so ever. I’ll be fine making the mold and regarding the density of the foam I guess I just have to experiment. The stuff supposedly expands about 30 times but if I put in twice as much and the mold is strong enough to handle the pressure I think I’ll get a fairly strong blank with an average weight. Anyone done something like this before before?
What is normally done to a stringerless board to make it strong enough? I’ve seen boards with what looks like carbon rails and I’ve seen carbon patches going from the nose all the way back to the front foot area in about a two inch long string on top and bottom. I’ll be using resin for this project by the way. Not epoxy.
How difficult is the glassing going to be? My mate just made a board for wake surfing from pealing the glass of and reshaping an old broken board and it looks pretty good.
Yeah, I’ll post photos of the madness whenever I get started. Will be interesting for sure.
If you are thinking about using 2 part pour foam or “Great Stuff” insulating foam don’t bother. Go buy a surfboard blank or a ask for a second if you want to save some money it will be cheaper than trying to make your own.
Either that or buy a used piece of junk at a swap meet and strip off the glass. Thats how most if not all shapers got their start.
Learn how to measure the board your riding now that you want to copy. Apply that knowledge to your stripped or new blank.
Why can’t I mold my own blanks from polyurethan? That would minimize the shaping I would have to do. Just want to mess around with the tail and rails for starters. And make a replica to see how it rides compared.
he warned you…there is a lot more to it than you think. If you get a somewhat sucessful looking blank, youre gonna waste resin/glass, etc. on it because it will most likely crush and delam, and expand or shrink. spend that time collecting cans from dumpsters or something so you can purchase a 60 dollar good blank, probably less w/o a stringer, DON"T DO IT!!!
If you want a replica to see how it compares… think about how many things will be different in your own home blown blank from what you have as a surfboard. Also, the shape of a blank made from a finished surfboard is bigger than the surfboard itself. So, everything is different, not much to learn from the differences, though a lot of learning still can be done.
From where i am sitting, making molds for surfboard fins is a lot more interesting…if you make them with glassfibre and resin of course, and not foam…
You sound like you will go ahead, so keep your promise and take plenty pictures, maybe even the first video?? Especially the pouring part i want to see.
I think I’ll do it. My dad repairs boats for a living and do all kinds of weird things with fiberglass and resin. He said he could make a mold and fill it with polyurethane under pressure to get a board strong enought to not need glassing. I think that’s going to ride pretty stiff and from what you say with the foam expanding after it is taken out of the mold it does not sound like a good idea. But if I get the ratio right I think I can make a pretty solid blank that want dent too easy and if it expands a bit after molding I guess I can just leave it for a week before shaping it. Or how long will it keep expanding after it’s taken out of the mold?
I’ll try some smaller pieces first to see how they behave. Also, it seems the ones making blanks use concrete molds. Was hoping a sturdy fiberglass mold bolted together would do…
You would never get time to bolt it together, as soon as the polyol starts its reaction it is rising, A number of the pro companies in the 60’s used fiberglass molds, but they broke down in time from the internal pressure.
The body of the mold will need to be at least 3/8" thick, laid up with 32 oz roving, mat and chop would crack, without the proper barrier paper, the blank will be nothing but swiss cheese, the mixing needs to be so that it is not aerated, adding more bubbles to the mix.
An organic VOC cartridge resperator in a must, the isocyanates are very dangerous and exposure leads to sensitisation.
I’ve been building boards for a living for 51 years and I do NOT attempt to waste money on TRYING to blow my own foam, I’ve been privy to the methods of Foss, Surfboards East, Walker, Clark, Green Valley,
When Clark shut down, start ups all hired up Clark’s empoyees immediately, they still could NOT blow decent foam.
Clark used 10 day out weather forecasts, temp control, digital weigh outs, there are NO benifits to try to blow your own foam or every surfboard maker would be doing it them selves
I was talking about expanding/shrinking when you lam it. don’t do it, but if youre still stubborn, then put pictures of it up here so the next person who wants to try it will think twice
if you can get a hold of THAT dvd , do yourself a favour and watch the bit where the guy [del cannon, apparently] sneaks into the bay [?harold walkers, apparently] to
'blow some foam'
watch closely what happens next ....
hungry pete ,
as wouter said ...
if you are DETERMINED to do it anyway , please make a video of it ?
I am not one to discourage people , but if jim says not to , that's reasonable enough warning for me , considering he's been around boards for as long as I have been alive , and especially the foam blowing side of things ...I don't think too many other swaylocks guys have ! so , yes , his advice is worth heeding .
besides , blanks are readily available with stringers nowadays , making them easier to template , cut , plane , work on .
please keep us updated , whatever happens ...and ...be safe , above all else ....chemicals can be nasty things , as can dust ...[ I get the itch , and the cough ..... I make fins occassionally]
you have been warned. Just take careful measurements. Spend money and get it it cut out of a normal blank on a shaping machine. I was young and fool hardy once too. I tried making homemade beer. I didn’t listen to anyone who told me what to do. Let’s just say after that I took the advice and now I brew some pretty F****** good beer, good enough I got an offer to be a head brewer recently.
first of all, I’m not doing this to save money. blanks are not available in norway and if they were I don’t think I would be able to shape a decent board. if I can make a copy of my board I have a good starting point. it is a bit thick and wide so it could be a decent semi step-up if I refined it a bit and rounded the tail of I think. that was actually what I wanted advice on but I’ll definitely save that for when/if the blanks turn out half decent. also I want to see how my tech would ride/feel compared to the real thing. it will be a few fractions of an inch bigger due to the blank being the copy but I’ll fix that with sand paper.
anyway. made the test pieces today. here are pics as promised.
I went heavy on the clamps. probably too much but after all those scare storys I just felt I had to. the foam was supposed to expand 30 times but only allowed to expand 15 times. will open it and have a look at the foam soon.
I also made a pice that was allowed to expand freely. I hold a little pice of it in the last picture. it doesn’t look so bad. will cut the whole pice I made in half and look closer at it later.
I’m pretty sure this can be done. had plenty of time to mix the stuff and clamp the mold together.
