Bassbme Posted June 13, 2020 Report Share Posted June 13, 2020 And I don't mind saying kind of jokingly, that it was a somewhat emotional lesson learned. I broke both of the crawtube injection molds that I made. Pretty positive about the cause of the breakages. I have a tournament tomorrow and I was doing up a bunch of baits. I noticed the molds were getting hot and I was getting a little more flash with the usual amount of clamp pressure I've been using, and I squeezed the clamps just a little tighter. Pop !!! The top half of the mold for the larger bait broke in half, crossing the cavity of the two bait, mold. When that happened I looked at the mold for the smaller bait, and found a crack that's about half way across the top half of that mold. It's still together, but probably not for very long. Very disheartening to say that least. I'm going to be remaking both molds, but in the mean time, do you guys think there is any shot at salvaging them? The one that's completely broken is a very clean and well mating break. I was wondering what I could glue it with. I'm thinking some Elmers? Anyhow .... I now know that when the molds start getting hot, take a break and let them cool down. I should have got my head out of my you know what, and thought that needing to increase clamp pressure to keep the flash down was a warning sign to let them cool down. I was just in a hurry to get enough baits made for me, and for some to give to my tournament partner. Ah well. Lesson learned. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted June 13, 2020 Report Share Posted June 13, 2020 (edited) For an emergency repair to get a few extra pours, I would suggest a rubber cement. A hard/rigid glue would just break away the first time you clamp. But basically, the mold is lost. It is advisable to use load spreading soft wood plates for clamping, rather than direct clamping, add a layer of rubber sheet, even better. I always sanded the clamping surface of my POP molds on a belt sander to remove any high spots, to reduce uneven clamping forces. Dave Edited June 13, 2020 by Vodkaman Quote Link to comment Share on other sites More sharing options...
Saugerman Posted June 13, 2020 Report Share Posted June 13, 2020 Seems like I once repaired one of my molds with JB Weld. You might give that a thought. Quote Link to comment Share on other sites More sharing options...
mark poulson Posted June 14, 2020 Report Share Posted June 14, 2020 (edited) If you build some matching mold boxes, with 1/4" plywood bottoms and 3/4" x 3/4" borders, spray the box insides with some kind of a clear acrylic sealer, and mix some yellow carpenter's glue into you POP just before you pour it into the mold box, the molds will be strong enough to clamp, and will last for years. I have some that are more than 10 years old and they still injection pour just fine. I line the bottoms of the boxes with fiberglass drywall tape, for additional reinforcing, and put some 1" finish nails around the inside of the borders to help anchor the POP, but I've found that, on the two occasions I had to remove the POP to remake a mold half, the carpenter's glue sticks to the mold boxes very well by itself. Be sure to mark the cavity locations before you install the 1" nails so you don't drill into them when you drill your 5/8" sprue holes. I use cut off 8D nails to align the two box halves, and clamp the halved together after they're poured and cured to drill the 5/8" holes with my drill press. Try and keep the baits 1/2" away from the borders, so you can carve tapered holes from the 5/8" sprues to the cavities. Edited June 14, 2020 by mark poulson Quote Link to comment Share on other sites More sharing options...
