The Themac grinder did not have a guard so I used the pink foam to make this. The Kush head is still on it here, but I it is already on the lathe ready for boring. This is the ideal use for lost foam since I only need one and there was less than an hour in fabrication not counting the coating time.
Cool, less than an hour. That's how it's supposed to be. (mmmmble, mmble, not counting the coating time)
Thanks guys. I used the drill press as a jury rigged overhead router and free handed the ribs. That's scary! But it is nice not to worry about draft or grain or followers or undercuts. The cross sectional thickness was only 1/4 " but the ribs helped feed the outer flange with no shuts or folds. I poured at about 1250*.
Nice cool pour. The shape and features of the part and central location you selected for the sprue were no doubt helpful for that. LF is great for one-offs and pretty much only limited by your ability to shape the foam to your satisfaction. Depends on how finicky and level of detail you want but fillets are a bit of an art. For up to 1/4" radius I've found pattern makers wax fillet and fillet wiping tools to work well but for larger radii, say up to 1.5" I've never found a suitable bulk filler so I machine features like that into the patterns. Post up the finished product on te grinder when you get the chance. Best, Kelly
I machined the guard this morning and mounted it for another mock up of the crankshaft grinder. The swing arms and bases are done with conventional patterns since I needed more than one, and machined them siamesed to insure the centers and keyways matched. I'll add a cover for the side of the wheel and match drill to the bosses. One of the machine tool suppliers had a clearance on 8" left hand digital calipers so I chopped one up to give me a DRO for the X axis.
Very nice addition, bigger than I thought it was from the as cast pic. Are you going to make an outside cover for it as well? I suppose the bosses/ribs are to attach the outside cover?
