gawski Posted February 10, 2005 Report Share Posted February 10, 2005 Back on June 16 2003 there was a post by OHIOMIKE in reference to a vacuum box he created to attach to his shop vac so he could pull the plastic thru the mold. Does anyone have information on how to build this? It sure sounds interesting! Quote Link to comment Share on other sites More sharing options...
jigmeister Posted February 11, 2005 Report Share Posted February 11, 2005 I'm not Ohio Mike but I did make a low cost vacuum chamber to aid in pouring some two-part molds I made . Get a 5 gallon plastic bucket (a square one works best if you can find and some laundry detergent is sold in these) . You will also need a shopvac to pull the vacuum . Drill a hole in the side of the bucket the size of the attachment wand on the end of the shopvac hose just above the bottom of the bucket. Instead of the lid I cut some plywood slightly bigger than the outside dimintion of the bucket out of plywood . Put some foam weatherstripping tape around the bottom of the new plywood lid to form a seal to the bucket. Drill a hole thru the lid that will line up with the sprue hole in your mold . You can use hi-temp silicon to make a bead on the bottom of the lid to seal between the lid and your mold . You will have to devise a way to clamp or attach your mold to the lid with wood, straps, etc. depending on the configuration of your mold. Get everything set and heat your plastic after lubing your mold cavity(s) liberally with Pam. Turn on the vac and pour . After cooling gently pry the mold halves apart . If you have any bubbles or voids in the finished bait scribe a fine line in one of the mold halves around the void area to the outside edge so the vacuum can pull the plastic in . Its a trial and error thing just be careful not to make these vents too big or the vacuum can suck about all the hot plastic out while pouring . Hope this helps ...jigmeister Quote Link to comment Share on other sites More sharing options...
Mike Poling Posted February 11, 2005 Report Share Posted February 11, 2005 OhioMike here, The box I made was 6"W X 12"L X 2"Deep, with a hole drilled on one end to plug the hose into. For the lid I took 2 pieces of aluminum and just set them on the top. That way I could control the width of the slit by moving them up and down seperately. When I first started using it I taped the lids to the box to get a good seal. As jigmeister said, I no longer tape them down, a shop vac gives you all the vacuum need without sealing the lid, alittle too much & it will pull the plastic right thru. I also use a foot pedal to controll the on-off Quote Link to comment Share on other sites More sharing options...