Dearmitt1976 Posted March 23, 2015 Report Share Posted March 23, 2015 I recently purchased a ring swimbait mold and I'm having issues with the ring not completely filling, the always have little chunks out of the rings. I inject it with two other molds and have positioned it first, second and third and have had no issues with the other molds. Any suggestions on what could be causing this? My plastic is always poured at 350. Thanks in advanced for any help. Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted March 24, 2015 Report Share Posted March 24, 2015 You have three ring molds, and one does not fill? Rings or even ridge molds are one of those that benefit from proper thought in venting. Post a picture of the mold and I'll see if we can make any suggestions. Quote Link to comment Share on other sites More sharing options...
Bogbaits Posted March 24, 2015 Report Share Posted March 24, 2015 Sounds like the plastic is too hot when you hit that mold first,let your plastic cool a bit before you shoot it Quote Link to comment Share on other sites More sharing options...
mark poulson Posted March 24, 2015 Report Share Posted March 24, 2015 I shoot a 5 cavity ring craw mold (Yum Wooly Hawg Craw) with 330 degree plastic, and the cavities all fill fine. The flippers are vented, and I spray the homemade mold with Pam before each shoot. Quote Link to comment Share on other sites More sharing options...
Bassinfool Posted March 25, 2015 Report Share Posted March 25, 2015 Sounds to me like a problem with the plastic being too hot. Try shooting it at 320-335 and see if that doesn't solve your problem. I use a small paintbrush and swipe some worm oil on some of my harder to fill molds. Quote Link to comment Share on other sites More sharing options...
Dearmitt1976 Posted March 25, 2015 Author Report Share Posted March 25, 2015 Thank you guys, I'm gonna try again tomorrow with your suggestions and see what I get. Quote Link to comment Share on other sites More sharing options...
Dearmitt1976 Posted March 26, 2015 Author Report Share Posted March 26, 2015 I tried shooting again using temp of 225-230 and still getting unfinished rings. My brush hog and craw completed good during same shootings. Quote Link to comment Share on other sites More sharing options...
Dearmitt1976 Posted March 26, 2015 Author Report Share Posted March 26, 2015 Here is a picture of the mold. Quote Link to comment Share on other sites More sharing options...
DaveMc1 Posted March 26, 2015 Report Share Posted March 26, 2015 try shooting it very slow and see what happens. Quote Link to comment Share on other sites More sharing options...
smallmouthaholic Posted March 26, 2015 Report Share Posted March 26, 2015 You said pouring,then shooting. Which is it?? You also stated you used 225-230 degree plastisol.I'd check your temperature equipment. I can shoot 280-290 degree plastisol from a heated injector but not 225-230. Put you mold in a vise and tilt the entrance of the mold upward. As suggested earlier,just let the weight of your hand push the injector downward-slowly and hold for 5 seconds.Top off your mold as the plastisol receeds Are you using new plastisol or used plastisol? 1 Quote Link to comment Share on other sites More sharing options...
Dearmitt1976 Posted March 26, 2015 Author Report Share Posted March 26, 2015 I inject the plastic and 325 not 225 just a typo. I'm using new plastic as well Quote Link to comment Share on other sites More sharing options...
smallmouthaholic Posted March 26, 2015 Report Share Posted March 26, 2015 I inject the plastic and 325 not 225 just a typo. I'm using new plastic as well Injector tip- Pull the plunger all the way back( w/ the tip of the injector off.) Check the top of your injector(behind the plunger for pieces of cured plastisol & remove if necessary.) Spray the inside of the injector w/ PAM then depress the plunger all the way, expelling all the old plastic remnants and PAM. Wipe off the "O" ring or quad ring,which ever is in your injector.Now you have a smooth,operating injector. Using an UN-heated injector CAN/MAY lead to the internal plastisol cooling off. If you try and compensate by over-heating in your microwave, that can/may lead to other problems. Note to Frank- You're successful w/ you non heated deal and that's great. Not trying to start a heated/non-heated injector war again. I personally will not work w/ out a heated injector system. 1 Quote Link to comment Share on other sites More sharing options...
mark poulson Posted March 26, 2015 Report Share Posted March 26, 2015 (edited) I let my injector tip sit in the hot plastic for 20+- seconds to preheat it, then draw and expel some plastic, before refilling the injector and shooting. I do not shoot a lot of big molds at once, so I don't know if that will work for multiple molds, but I works for the six single cavity skirt molds I shoot at the same time, and for the five cavity wooly hawg craw injection mold I made. Edited March 26, 2015 by mark poulson Quote Link to comment Share on other sites More sharing options...
edgecrusher Posted March 26, 2015 Report Share Posted March 26, 2015 Do you have bubbling in the plastic? maybe the bubbles are pushing toward the vent points causing this? Quote Link to comment Share on other sites More sharing options...
tsic Posted March 26, 2015 Report Share Posted March 26, 2015 This is how I pre-heat my injector and molds while warming up my shop I have a forced hot air furnace with a 6" pipe coming through the wall into the shop. When I first fire up I put the molds-injector in this pipe for a couple of minutes it doesn't take long. I was shooting some tubes today and decided at the last minute to shoot a drop shot worm mold without heating it first. only filled 1 of the five tails of these baits, warmed up the mold reheated the plastic, and the second shot came out great Quote Link to comment Share on other sites More sharing options...
txsteve Posted March 28, 2015 Report Share Posted March 28, 2015 I think you may have a vent problem with the mold. Is the incomplete ring always in the in the same spot? If so look at the vent on that spot of the mold and deepen it slightly. Quote Link to comment Share on other sites More sharing options...
fishon-son Posted March 29, 2015 Report Share Posted March 29, 2015 maybe send the mold back to the maker and see what they can do with it to get it to shoot better for you...call them first before you try to work on it yourself..once you work on it they wont touch it...... 1 Quote Link to comment Share on other sites More sharing options...
McLuvin175 Posted March 30, 2015 Report Share Posted March 30, 2015 (edited) Looks like air entrapment to me. Ring type molds are a bugger because it is hard to vent out all of the air in the mold when you shoot them just because the nature of how the mold is cut. How do you orient the mold when you shoot it? It would be ideal if you shot the mold with the parting line (the seam on the bait where the two halves of the mold come together) is in the north/south position. This allows any air to rise to the top as you shoot the mold and be vented out. If the parting line is not in the north/south position but instead in a east/west position the air will rise to the top of the rings and become trapped with nowhere to go. Using some additional hand pressure when you shoot could help reduce the incomplete rings but not as much as proper venting. Edited March 30, 2015 by McLuvin175 Quote Link to comment Share on other sites More sharing options...
SlowFISH Posted March 30, 2015 Report Share Posted March 30, 2015 Looking at the pics - it seems like you're trapping air away from the vents. I think there are many suggestions above to try - I'd also recommend one easy one..... shoot the mold on a slight angle instead of straight up and down (say 20 or 30 degree tilt).... I have a few molds that seem to fill better when clamped in my vice on a slight angle... theory being the plastic fills "down" in the mold first then pushes the air up/out as it fills..... on a mold held perfectly vertical there is no "up" for the air to seek as it fills and trap in the ribs areas. Hope this makes sense. J. 1 Quote Link to comment Share on other sites More sharing options...
