Some things to try. 1. Better keying of the mold halves. I cut an angle on the outer edge of the first half, often with notches placed as needed to prevent any misalignment lengthwise with the edges.
2. Clamping the mold together. Use two pieces of MDF, coated with clear lacquer to seal them, to sandwich the mold. Hold together using mold straps. They use a web belt that does not stretch much and an over-center locking buckle. 3. Fill the mold from the bottom up. Make the fill channel go down to the bottom or near the bottom of the cavity so that as the resin goes in, the air can escape up vents at the top. 4. Cut vents with a fiber reinforced cutoff wheel in a Dremel or similar rotary tool. NOT cordless or one that runs off a 12V wall wart. They're not powerful enough. 5. Complex molds often need to be tilted at just the right angle while being filled so that air can escape from some places, especially spaces that are horizontal and thin. 6. Put it under pressure, as I mentioned in my previous e-mail. 7. For especially difficult castings you might try filling the mold then putting it under vacuum followed by pressure. The mold will need extra tall filling and venting channels to keep the resin from bubbling out under vacuum. 8. An idea I've been kicking around for a high speed vacuum system but haven't yet had a need for... Get or make a cylinder with at least double the volume of the tank the mold will be in. Fit it with a sealed piston and valves like a bicycle pump, but set up to draw in instead of push out. Use a heavy weight to pull the piston out (like yourself on a long foot pedal) or a chain or hydraulic cylinder or electric driven ball screw. The idea is that the piston can be moved quickly and in one stroke will drastically drop the pressure in the tank. If setup with reversible valves, air could be let in then the piston pushed the other way to quickly raise the pressure in the tank. Make the check payable to... ;-) ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
