stonecold13 Posted August 15, 2012 Report Share Posted August 15, 2012 (edited) first of all , my English will sometimes not good , I am sorry for that I have made my custom mold , it 's 3 cavities . I can not get it to filled , I have vent every single area just like in the picture the result will come like this every time ( every time really ! ) 1 the middle lure's feet will not be complete as I compare in the picture but the other two will complete , this happen as same every time . 2 the left and right lures will have a defect like I point by the red arrow I think it's because the air can not get out all . I try to fixed this for 2 days by vent and pour , more vent and pour , until I do not know where to vent next I inject slow , filled the spru after inject anybody have an idea , Please help me T_T Thank you very much everybody , I will have to tell you guys that this website make me from a boy that know nothing until now I have my own mold , Thanks to every single post in here , I would like to say this for long time . stonecold13 Edited August 15, 2012 by stonecold13 Quote Link to comment Share on other sites More sharing options...
atijigs Posted August 15, 2012 Report Share Posted August 15, 2012 Here are a couple of thoughts. The center frog will always be a problem. As the body cools and the plastic shrinks it will pull plastic out of the feet instead of the sprue. I also believe your defect in the two side frogs is caused by cooling plastic and not air entrapment. Perhaps keeping pressure on your injector longer and topping off your sprue may help. Otherwise I would use a larger sprue runner to supply more hot plastic to the bodies as they cool. If you are doing the machining of the molds yourself you could make your life easier by giving each body its own sprue. Put one in the bottom for the middle frog. I don't know how else you will get that one to work. Good luck, you will get it. Quote Link to comment Share on other sites More sharing options...
Romeo D Posted August 15, 2012 Report Share Posted August 15, 2012 I think the middle one will always defect at the feet. The air is trapped and cannot get out, maybe having the mold remade with all the frogs the same layout, feet down will help you. As for the body denting, I agree with atijigs, on a larger sprue/runner. Quote Link to comment Share on other sites More sharing options...
powerworm Posted August 15, 2012 Report Share Posted August 15, 2012 i do agree but for different reason per the feet they are not getting filled at all because the thinner legs are cooling off before the feet ever get a chance to get filled up maybe increasing the thickness of the legs might help there venting will not i believe help here as it appears adequate. as for the body getting dents the body is the thickest part of the part and therefore holds more heat and it takes longer to completely cool down and quit trying to draw more hot plastic into itself to stay expanded your sprue and runner design appear adequate but maybe off slightly as to the diameter or capacity holding pressure on this mold as is will not help either problem you have as the gate where the bait meets the runner is closing off prematurely and therefore your bodies dont stay filled up completely. Quote Link to comment Share on other sites More sharing options...
bear21211 Posted August 16, 2012 Report Share Posted August 16, 2012 (edited) Open Your gates going into the cavity drill small holes in the middle of the feet through the mold Edited August 16, 2012 by bear21211 1 Quote Link to comment Share on other sites More sharing options...
mark poulson Posted August 16, 2012 Report Share Posted August 16, 2012 Do you guys think preheating the mold would help? Quote Link to comment Share on other sites More sharing options...
stonecold13 Posted August 16, 2012 Author Report Share Posted August 16, 2012 (edited) thanks a million to Atijigs. Romeo D. Powerworm. Bear21211 and Mark Poulson I will do just like your advices , first will be larger gate that enter into each cavity let see how it s work thanks again Edited August 16, 2012 by stonecold13 Quote Link to comment Share on other sites More sharing options...
Romeo D Posted August 16, 2012 Report Share Posted August 16, 2012 Stonecold, You already know the outer 2 cavities don't have a problem with the feet filling completely. They are all shot at the same time and the middle one consistently has the problems with the feet. The only difference between the outer two and the middle is the way it is oriented in the mold. Keep the feet down on future molds and you should resolve that issue. 1 Quote Link to comment Share on other sites More sharing options...
stonecold13 Posted August 16, 2012 Author Report Share Posted August 16, 2012 Romeo D , thank you and this will be one of my lesson at first I do not think that orient them in other way will have any effect , now i knew it does . thank you very much Quote Link to comment Share on other sites More sharing options...
Bass4Me Posted August 16, 2012 Report Share Posted August 16, 2012 This is just a shot in the dark, but would the middle frog legs fill up if he lays the mold on its side and then inject the plastic. I don't remember reading if he is warming up the injector by loading it and expending the hot plastic at leaset 3 times? Quote Link to comment Share on other sites More sharing options...
rayhorse Posted August 16, 2012 Report Share Posted August 16, 2012 Hi everyone. I had the same problem when I start machining my first mold in Mexico, At that time , I made a couple of changes to my mold and I realize that the lizzard head was cooling before the runer. So I modify the size of the runer several times until the head of my lizard came out with a nice shape. Make a pocket at the end of each runer, this way the body will cool down first than your runer. Try to make just one cavity mold until you get a nice shape. Quote Link to comment Share on other sites More sharing options...
stonecold13 Posted August 16, 2012 Author Report Share Posted August 16, 2012 thank you very much Bass4me and Rayhorse Quote Link to comment Share on other sites More sharing options...
jigtwins Posted August 30, 2012 Report Share Posted August 30, 2012 Don't know if you got this fixed or not? But I am with bear on this. I would drill a small hole say .015" in the feet. It will flow much better. just make sure to face the holes in a safe direction the first time to see how it vents. And you will have to poke the plastic out cause it will break off sometimes. I made a swim bait mold that had tail fill problems, and I drilled the tail. Worked perfect! Quote Link to comment Share on other sites More sharing options...
carolinamike Posted August 30, 2012 Report Share Posted August 30, 2012 stonecold, from the looks of it its gonna be really hard to do anything with the center cavity. getting the body to fill and then trying to push the plastic uphill into the legs is going to be very difficult. if it was me before drilling or anything i would try completely blocking of the center cavity, this will put all of your pressure on the other 2 baits and you dont have to make the plastic go uphill to fill the legs. Quote Link to comment Share on other sites More sharing options...
carolinamike Posted August 31, 2012 Report Share Posted August 31, 2012 (edited) Bob, was'nt me dude. We've talked about venting before but I cant remember anything about drilling out. As far as the gates go, bigger is always better. I've just recently opened up the gates on a production mold and this mold has been tough to run for years I worked with and it a little bit and it works so much better now, but with 2 runners running out the side and having to fill the body first its going to be tough to get that center bait to fill every time because you're loosing pressure with the 2 side cavities and the center cavities you're actually trying to push plastic down and then back up. There again, you cant have too much venting either. Edited August 31, 2012 by carolinamike Quote Link to comment Share on other sites More sharing options...
IBHUFFY1 Posted August 31, 2012 Report Share Posted August 31, 2012 Why not just block off the injection port for the middle cavity, flip the mold over, and cut a second injection port? You would have to wait till the first round cooled, then shoot the second. but it would work. 1 Quote Link to comment Share on other sites More sharing options...
carolinamike Posted August 31, 2012 Report Share Posted August 31, 2012 IBHUFFY1, that is a great idea and I bet that cavity would work better also. Quote Link to comment Share on other sites More sharing options...
Lakeside Molds Posted August 31, 2012 Report Share Posted August 31, 2012 Why not just add a couple of small gates from the runner for those two middle feet? Quote Link to comment Share on other sites More sharing options...
stonecold13 Posted September 1, 2012 Author Report Share Posted September 1, 2012 thank you so much everyone , I have to admit that I cant not filled the body of those two on the side , even I try to open the gate but it still happen the only way that I can do is to pour the belly first and then inject , this work great, for the center cavity , I am just block it because I am not ready to drill it , LOL , just think that someday I will figure something out , And today after reading , I think I might have some idea thank you again every one , you guys help me so much 1 Quote Link to comment Share on other sites More sharing options...
