I did my search regarding EPS shaping but it all comes down to using a hotwire to cut or how you can still use a plainer. It has also mentioned useing more grittier sand paper when fine sanding 50-80 grit & thats it.
My only questions for you EPS shapers…
Can you shape it w/ a surform? I’ve contacted a local dealer and they said you can… as long as the tools are new and sharp…But then I talked to a seller of the EPS and he mentioned that a surform pulls out beads in the foam and is a poor tool.
I watched Greg Loher shape a 2# EPS board at Cerritos College back in December. He used the same methods that are used to shape a poly blank. You might have to make minor ajustments to your style but it will all work out. I’m playing around with the stuff right now. Its different but not a big deal so far.
Mike Eaton uses an air-powered 6" disc sander on his EPS paddleboards - 1#, up to 19’ long. That’s a lot of foam
A 2’ block with 50 grit is almost as fast and gives nice, smooth lines.
Haven’t tried the wire brush yet, but can’t think of any reason it won’t work for roughing in.
The 16" surform would be ok, but why spend the $30 when a belt sanding belt is $6 and you can probably get a piece of 2x4 for free? The smaller surforms would leave you with bumps & dips because they won’t be big enough to span the lumps and give you fair surfaces. Probably fine for rail banding, though.
One of the problems I had in shaping my first eps blank was getting the last vestiges of my rail bands out of the board. In the right light you (I) can see them. With Poly-U I used a 4-5 foot piece of dry wall screen up and down the deck until they were gone. Screen tore the eps, however. Are there 5 foot lengths of sand paper available or another tecnique? Mike
There was an episode of “Monster House” on a few weeks a ago – they were shaping a giant skull out of EPS and using a round metal hand tool (I think It may have been called a curie) that is normally used to groom horses.
I got a bad blank a while back and shaped it. It had a couple nicks in it so I filled it w/ a filler they use for small holes. It looked fine and almost unoticeable. When I got it back from the glasser it had discolored and the spots I spackled had turned yellow. Is there a specific spackle you use so you don’t end up w/ this problem?
I haven’t shaped one yet but I’m getting close. Did you check out the photos I posted in that other thread?
I used white 50 grit sand paper on my blank halves before gluing in the stringer. Worked good. You need to find the thread from the Dec Cerritos College event. Lots of photos and good information.
Spackle…Greg Loher and Air Frame say to use Dap Fast and Final. Thin it out with purified water.
If you use hot wire cutters (bows, outline and rail band slicers) as well as one of those drywall sanders you can attach to a shop vac with some 36 grit through 220 grit sand paper and screen you can shape an EPS blank very easy WITHOUT making much of a mess. This is real important for me since I shape in the street in the full view of all my neighbors. for power cutting EPS, wood rails and tail and nose blocks a belts sander with a vacuum attachment and 36-50 sanding belts works wonders too if you want to go the power route. I like sanding power tools versus cutting power tools for shaping foam. Like you said though professional foam sculpters throughout the world use hot wire tools and a chain saw to greate their art way different than a surfboard mindset.
If you shape in a shaping room where you can clean up after and don’t care about the mess your making and adding to a land fill somewhere, then wire brushes work well as well as those Plekunas(?) shaping grit blocks or a 2’ or longer 2x4 with 36 and 50 grit sandpaper stapled to it. The longer your sanding block the better to cut down your rails, flatten out your bottom, or crowning your deck. You can also cut out special shaping forms out of wood and staple paper to it to cut out deck and bottoms. I agree with Jim Phillips in that it’s nice to hold your board on on end and be able to reach down to smooth out line or high spots way down the board so long handled shaping tools come in handy.
It’s good that you’re asking the questions. Why do we have to do it like? that is a good way to look at things. As I picture that picture of the scrungy half naked shaper/sander covered in foam or fiberglass dust with a papermask holding onto a skill100 or milwaukie sander, I am reminded of the “Marlboro Man” smoking his unfiltered camels.
the ultimate shaping room of my dreams would have a raised floor with a rubberized grating like that used in restaurant kitchens and a high exhaust fan blowing down on top of you to force the foam dust down in to the cavity below the grating and sucked out by another exhaust into a filter bag or dust capture room/trash compactor that has a water curtain screen on the outside to prevent dust/fume reaching the outside (think Rainbow vacuums). The same technique could be used to hold down you work so you don’t need those silly lead weights. Aside from the new CNC machines its amazing how neanderthal this process of creativity remains after all these years all we’ve added since the beginning is a planer and some lights against a painted background.
I found that a microplane blade in your surform works better than the standard surform blade, that slowing down your stroke with any tool (including a planer)or abrasive minimizes the bead tear-out, and that finer grit screen works best for polishing up the shaped blank. I don’t use screen for shaping, just 50 and 80 grit paper and surform. I do use an electric planer for the bulk of shaping, simply because it’s a more precise instrument and I…well…need all the help I can get!
I don’t know if anybody else has tried Sabs shaping with wire brushes, but they work great for cutting deep cuts (like a deck concave). It chews up the foam so you have to switch to sandpaper for the last 1/8" or so.
Quote:
the ultimate shaping room of my dreams would have a raised floor with a rubberized grating like that used in restaurant kitchens and a high exhaust fan blowing down on top of you to force the foam dust down in to the cavity below the grating and sucked out by another exhaust into a filter bag or dust capture room/trash compactor that has a water curtain screen on the outside to prevent dust/fume reaching the outside (think Rainbow vacuums)
Wait till you see what I’m working on now. I had a slight reaction to all the balsa dust so I decided to get serious about sucking it away! I’ll post when I get a little further along.
I’ve tried Custom Product’s “Patch n Paint” (from Home Depot) and Dap’s “Fast n FInal” (from Lowe’s). Both worked great, although I did get an area with some blue spots coming out of the Fast N Final (looked like Certs Candy). Greg Loehr and a host of others recommended Dap. The “Patch n Paint” board is doing fine after about a year of surfing on it. I think either is OK. Greg recommends using distilled water to avoid yellowing. Both my boards were tinted though, so I have no idea if the spackle yellowed.
