Here is ahaiku that expresses my feelings after a day in the garage w/ and eps blank.
I loved shaping rails
Then I bought some EPS.
EPS–you bitch!
Sorry for the profanity. Any tips for getting eps blanks to look good? Or should I just apologize when I give it to the glasser?
I swear–I was once a decent amateur shaper!
there is always a solution…
post some pics of the problem and there will be more advice than you can point a stick at.
ps.
like the haiku.
rif.
sorry, no dig camera…
the problem is the chunks that come out, especially on the curved surfaves of the rails. If the sand paper or planer gets even slightly caught, it rips out so much foam I feel like I must be shaping while blindfolded (I’m not).
so that’s it… can’t seem to keep it smooth.
yeah ok…
probably a mix of technique and materials here… what sandpaper are you using and how much material are you trying to take off? I have found that you can go to quite a fine grit and still remove a good amount of material without pulling foam. Probably doesnt take enough off to rough shape but definately good for smoothing off and making small changes, especially blending rail bands etc.
Also hold the block on a slight angle so it is slightly sideways as you stroke, this will pretty much eliminate hang-ups on most materials - every now and then switch the block the other way, it’ll give your hands a rest and youll end up with a more even surface. Even pressure and even speed are important too… Ive found that eps needs very little pressure… too much and you run into problems. Steady moderate speed.
On the weekend I tried a test patch where I went from surfform straight to a 320 grit sanding mesh and the finish actually held a reflection from the light I was working under… i was pretty supprised.
rif.
take is slow with the planer, and if youre using rough paper…
I’ll throw this out there: grit drum and sanding screen. Mine turned out great but I only used 120 screen, no power tools. Took a while, but was fun and buttery. I stare at them a lot and feel them up.
There shall be more 2 centses, I feel sure.
greg
I’ll second the need to use some fine tools for the job… I did a whole board in eps low density foam and never had any problems, I just did not use a sureform and no sandpaper under 80 grit… Perhaps takes a bit longer but it works, so “slow down everybody your mowing too fast”
Hope that helps
Christian
[=Black][=1][=Black][ 6]I loved shaping rails
Then I bought some EPS.
EPS–you bitch!
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Haiku of the year!
Hi Trucker -
The folks giving advice have more experience than I. I’ll toss my .02 anyway…
Fine grit and slow speed seems to be key. Even then, expect to prime the shaped blank with either an epoxy/micro balloon slurry or acrylic based spackle. There is good EPS and there is shitty EPS. Some EPS billets have pockets of loose beads that are indeed a bitch.
Greg Loehr has posted regarding EDRO process. Try a search for “EDRO.”
The EPS blank suppliers all use pretty good foam. Heavier densities with small beads seem to finish out the best.
Did you cut your blank from a stock billet or buy your blank ready made?
Greg, I don’t think he was asking about girls 
I stare at them a lot and feel them up.
greg
Hey Trucker,
Eps takes some getting the hang of…It definately takes a lighter touch.
If you don’t have a “barrell” planer (Grit thingy), you need to go slow with the the passes. Don’t push too hard and fast, or it will rip. This is the same with PU but an experienced shaper might do the initial rough cuts really fast anyway because the next cut will remove the rips. But you may not wanna take the risk, so just slide it really easy.
Same goes with a surform:- rough passes, then care. You have to calculate whats gonna be removed.
Hotwired EPS may have less density toward the middle if the slice you got is from the middle of a large block. Sometimes you can pick it in the light.
Fine shaping, Blocks with 80, 120 then gauze. Unless you have taken chunks somewhere, your finish can be virtually scratchless. It gets so that when you wipe fingers over the shape, you get that kinda mowed lawn effect, where the minute fluffy surface goes this way and that in lines.
As a rule, use the biggest tool to remove the maximum bulk, then go finer, its more accurate than scratching away at a big block of foam with fine first.
Speedy
Hey Trucker, if I had to guess, I’d say you were finishing your rails with a piece of sandpaper (or a piece of screen). Board on edge in the racks, paper held around the rail, one hand on the deck side & one on the bottom side, and you run that “c” shape along the rail, end to end, right?
With EPS, that particular trick needs a very light touch and you have to be able to hold the leading edge off the foam as you go.
I don’t do that one with EPS, I just use a very soft foam pad with paper held over it. Like a 2" thick piece of neoprene with 100 grit. You can press that pretty hard into the rails, actually, and curve it around. Forms the same shape, but for some reason the edge doesn’t catch the EPS.
Hope that was it…
Oh, and skip the surform altogether. More harm than good.
Yup!
It’s a different ballgame foresure.Spackle it to death…Naw, just a thin coat and sand it lightly.
Don’t kill yourself trying to get it pretty. Use Dap Fastnfinal to fill the voids, then sand it to 150 to make it pretty.
Then like Jim Phillips says, “I’ll make you and EPS board, as long as it’s white”
Hey all,
Thanks so much for the advice. The “damage” happened when I was using a sanding block to take edges off of my rail bands from the planer. I have a decent amount of wood working experience and have always used the sanding block as an intermediate step between the planer and the screen for PU rails. I guess I didn’t realize how much lighter I have to be w/ EPS… also, I’ve never seen an EPS blank before it gets the sealer, so I was wondering how ugly it should be. I have heard plenty of shapers comment on how much uglier their eps blanks are compared to PU…
Anyway, I hope you liked the haiku–that plus a little friendly swaylocks advice cleansed me of my frustrations and got my blank back on track.
By the way, totally off the subject, but how good was Trestles today??? Okay, it was small, but nice and clean and peeeeeeeeeeelin’.
Ah. You havnt hit the fun part yet. When the stuff starts gasing when you lam. Pretty little bubbles, though. Mike