Hi everyone, i am new to here as well as shaping and will probably have many questions on the processes. Anyway, I am attempting to shape my first board, out of EPS. The blank I will use will be glued and it is close tolerance. So my question is what tool(s) should I use to get the blank down to thickness. I have been doing some reading on here, and it seems people used mostly 30-40 grit paper to shape a lot of the board. Would this or a surform be better for the job?
Power planer
Surform is useful but I remember guys saying that it can create a lot of tears in EPS
Sand paper
hand plane for the stringer
Tape measures are handy
a hand saw
probably missed some stuff but the other guys can add to the list (or subtract however it may be)
But this is all stuff easily found using the search function.
I like a screen, and these 3-M sanding pads about 5"x7" by 1/4" come in med., fine, super fine… They are gray - got some new ones from the paint store, they last so long, and clean/shake out easy.
Surforms do pull, but I use 'em alot, then hit w/screen/pad, and spackle (sP)
I cut some MDF boards that are about 30" long and as wide as the belt sander paper.
cut the belt sanding paper and spray glue it to the MDF.
perfect sanding block.
I like the microblades for the surforms…they are more friendly to the EPS…less tearing.
http://www.foamez.com/shaping-replacement-blades-c-2_27.html
drywall sanding screens are also great when attached to a foam backing for hitting curves.
you can cut a 2’ long piece of 2"x4" (2x4 won’t bend much under pressure) long enough so that a cut belt sander belt wraps around up the ends. Then round the bottom edges of the ends so they don’t catch and “staple” your belt to the block as that way you can easily change it out later. Cut a similar length piece of 2"x2" and use a rasp or some sand paper to create a convex bottom on one and a concave bottom the other. Then wrap the belt sander belt up along the length and staple tight. now you have a tool to create flat bottoms, smooth outline rough cuts and to turn rails, as well as to put in concaves and something to crown decks with. You can even screw on some scrap cabinet handles for grip…
Take a piece of 40/60 grit and tape it face up on the thickest part of a rail on a board who’s rail you really admire then take a piece of scrap EPS and rub it against the sandpaper on the rail till you create a reverse image of the rail contour in the EPS. Now take off the same sandpaper and stick it in the curve wrapping onto the flat outside edges and tape it down. Now you have a rail band tool to help you smooth out your rails. It’s important to map the thickest part of the baord you’re imaging from though…
For fast planing and roughing through lots of EPS material out go find some coarse steel wire brushes used for cleaning or scraping things and use that to rough out the material before switch to the blocks
I think you might find most of this stuff just lying somewhere around the yard or neighbors yard.
no need for electricity or cords
no loud high pitch noises
but still messy
You can buy a vacuum connected hand dry wall sanding block to hook up to your shop vac if you want to reduce the mess but it won’t cut as nice and straight a line as a 2’ long piece of 2x4
Finally a couple sheets of dry wall screen course to superfine should help you smooth out the bubble before spackling.
40-60-80 and 120 sanding belts are all you need, You could probably get a combo pack of belts or paper somewhere cheap too.
One of the best tips I was given when shaping my first EPS blank, was to cut my paper and screens into little 3" x 5" rectangles. Use them when screening and sanding the rails. This gives you alot finer control and the paper doesn’t seem to catch as much.
How will the blank be glued? Epoxy, expanding poly, elmers wood glue?
Are the pieces narrow long sections running from nose to tail, or a big flat sheet like the Home Depot stuff?
The glue line can cause problems if you use one type of tool or another. The difference between the hard glue line and the soft foam will cause tearing and gouging.
A surform will work, but they usually only come in about 12" lenths max. A piece of 2" x 4" x 24" wood with a strip of very course belt sander media will allow you to sand across the whole board. My 2 x 4s have one type of grit on one side and a less course grit the other.
I also use belts without the wood to get smooth curves like the rails or top profile.
When I want to hack away at a lot of foam I use a rasp, then a surform then the wood blocks.
I don’t know what kind of glue is used, I am buying it already glued. As for the foam, it is in long narrow sections.