Enclosed Side Ski Press

[G]

What disadvantages would a ski press with the sides totally enclosed create? Of course the ends would be open so that the mould could be slid in before the air bladder was pressurized.

[littleKam]

just curious, what's the reasoning behind a totally enclosed ski press? are you trying to hold in the excess epoxy?

[Wheezer]

If you are sloppy (as I am) and excess epoxy isn't contained well then you may have the mold epoxied to the press. I've had to come in from the sides and crowbar the mold off the base.

[G]

I think an enclosed side design would be very efficient to build and could be made entirely out of plywood. If it has few disadvantges in terms of function then I was going to proceed with design and FEA to verify the concept. Also I have an idea for a cost effective way of getting it heated to 170 F.

Right now I am thinking the opening should be 8" across / 12" high and the overall length would be 80", based on some other discussions within the forum. It would be built to wtihstand a 50 psi load uniformly distributed and acting over about 350 sq inches on top and bottom. A quick calculation of the side members shows they each need to support a pure tensile load of 17,500 lbs. If the cross section is 3/4 * 80 = 60 sq in, then the tensile stress within the members would be 292 psi. This appears to be very reasonable stress for plywood. The cross members supporting the bending load needs to be analyzed using FEA to optimize their design and to look at the total deflection. The 2 x 2 press frame construction detailed in this site appears to limit deflection to about .009", so this can be used as a comparison to what my design may show.

[Greg]

I find it kind of nice to have an open press, mainly because you can keep track of what is going on it.

[littleKam]

^ same here.