I’m riding a new one I made. Pink stuff. I made it w/no stringer and a heavy glass job, so who knows. It doesn’t get that hot up here on the Oregon coast.
I made blue one once w/uni-directional carbon fiber “tape” and it bubbled up under that black on a hot summer day in Washington… Well, “hot” warm, and the black area was hot. The bubble was about the size of half a banana. I drilled some holes in it, injected epoxy, put foil and a sand bag on it… no problem. Then I painted the black areas white. Then I broke the board a couple years later.
Later I made a pink one, it has a low bubble where my left hand goes on the rail, but I did not do the 60 grit finish, and the glass job is 3x 4oz on the rails…
I like the fact I paid @ $20.00+ for the foam, and picked it up at the lumber yard a couple blocks from where I work.
I went back to it after reading about the success Surfding, and others, had with it, and the 60 grit idea. Plus, I saw a CI XTR 6 years old, no bubbles, little holes about 2" apart on the rails, at the hand area, and on either side of the stringer, about 2", from near the tail to about 2/3 the way to the nose.
If this is the stuff that Shapers Aust. is bringing in then I've done a few of them.
my latest board is from one of these blanks. 5'11 x 18 3'8 x 2 1/4 squash tail thruster 6oz bottom 6oz deck with a 4" beam of 4oz running the length of the stringer. I love it.
super dent resistant and super light,but I have had a couple snap.
never had a delam problem even on boards that are a couple of years old. I finish at 80# on the XPS.
The problem with these blanks is the stringer glue ups, my boards stringer was 15mm off centre at the nose, which is why its my board.
A bitch to shape but you get a super light, strong and responsive surfboard. (sounds like a f##cken sales pitch doesn't it?)
Now you’ve started a rumour. Actually all I really wanted to ask is what grit are you starting off with to finish your iXPS or are you just using 80 grit?
I’ve actually brought a few of these in to Australia. They are OK but cutting them is a problem because they burn/melt. As with all xps foam they are an absolute nightmare to shape. Cut a few on the AKU machine but were burnt so bad they required hand shaping after. Mine were about 3 1/2 inches thick with fully flat deck (hotwired). Shaped one by hand once and it took about 4 hours of hard labor. Used my skil 100 with Shapers barrell and it was melting into big chunks. Finally got it done and the customer loved it but jeez it was a wrestling match. I think they mold this foam into a more reasonable blank but I’ll stick to the FibreFlex recipe for all of my epoxies.
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super dent resistant and super light,but I have had a couple snap.
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Now you've started a rumour. Actually all I really wanted to ask is what grit are you starting off with to finish your iXPS or are you just using 80 grit?
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If it comes off the machine I start with either 40# or 60#.
A hand shape and you are mowing for ever because of the foams tendency to melt and ball up if you go too quick. Rails can tear if you pull too quick with the heavier grits also.
For production this foam is just way too slow to work with unless you get it CNCed. I think if your CNC guy know what to do you have no problems with machining this foam.
No delam issues like the dow stuff I was shaping in the 90’s. I always used a wax comb to rough up under foot. It looks less messy than gritty sandpaper.
I’ve got 2 cutting heads that I use for different stringer and blank configurations. Its at the stinger mostly where the problem lies because you need to cut slower and the wood heats up the cutting head.
To be honest, I’ve moved away from experimenting with these foams. I know many people on these forums love the epoxy/eps/xps boards, but from a production standpoint, they are difficult. Call me lazy if you will, but I’ve always had the greatest success with standard PU/PE and feel there is nothing better at the moment. The look, the feel, the performance, it’s hard to beat.
I don’t work in production, but I think it’s about time that if people what a board with all that extra work involved, and those boards perform and last as long as they say, then they can fucking well pay for it. “Cheap” is, is what cheap gets. No reference to yourself by the way rmshapes or any other surfboard manufacturer really.
Something for those working with Chinese made blankets to think about. Ever wonder if those blankets will turn out to be like The Chinese dry wall? In a year or two Shapers, Glassrs and other board makers coming down with very odd symptoms and strange diseases? Just something to think about while you cut that new blank.
XPS is complicated to process. With a stringer you can get melting along the stringer because the XPS is heat senitive. The key is to increase the feed rate and go stringerless. Plus slow down the rotation of the cutter head by 40%
However like you say why hassle it? Surfers will not pay the for the upgrade. PU/PE is definitely the most production friendly there it. The EPS is not so bad as long as you stay with the molded and keep away from the construction grade billets.
I just hand shaped an XPS (blue Dow) board. I found that I had to go really slowly with the planer to get nice smooth cuts. If you take your time it cuts really clean with a standard power planer.
I heard that if you use a machine to cut the blank, you need to slow the cutting head down. Makes sense since slowing down the forward movement of the planer made a world of difference. Doing it on a machine would be better since I had to move really slow. When I routed out the fin box slot, it was smooth as silk, so a machine with a router bit, or a narrower bit may be better.
I would like to try a few more to get a better feel for this foam, especially the glassing. I think there may be a nice advantage in the glassing if you are able to laminate it cleanly then just add a fill/hot coat. No major sanding after that, no worries about pinholes, just smooth it down where needed and do a light spray to get a nice finish.
Ever wonder if chinese blanks are just recycled Chinese drywall? But really no worries you have a thine layer of fiberglass between that cancerous elements and caustic materials in the blank. happy shaping everyone.
A year on this thread is back from the dead! I’ve had my iXPS board for a few months now so I thought I’d comment. More ding resistant, and a bit lighter than PU. I find it a little livelier than PU as well. Tricky to work with and more expensive though.