5" senkos with a 2 piece cnc mold - struggling

[crankbait2009]

I have a 3 ounce dual injector. I started making 4" flukes and all is going well.  Still trying to get the right amount of glitter per fluke.  Work in progress.  Overall, I'm pleased with the way the fluke turns out.

 

tried to do the 5" senkos, and that is a struggle.  When I inject the mold, the injector seems to stop prematurely in the process.  I thought it was full of plastic, so I stopped pumping.  After a few minutes, when I open the mold, the first worm in line seems to fill in with plastic.  The rest of the cavity's have only half the worm injected and the tubes are hollow.

 

I have tried the process over.  double checking that my injection temperatures were within range, which they are.  plastic is completely cooked.

I've gone as far as injecting the plastic, then when the injector stops, I immediately refilled the injector with plastic and follow the previous fill.  (I think it all has to be injected at once.  Can't follow with multiple injections.)

 

I am starting to think that the problems I am having are due to the difference in temperature from the hot plastic and the cnc molds.  The plastic is setting faster than I can inject.  I've heard some say to use a heat gun on the mold, or even a hot griddle. but wouldn't heating the mold cause the aluminum to warp?

 

Is a 3 ounce injector large enough for a 4 cavity, 5" senko mold?

 

any suggestions?

I do have a ribbon worm mold coming tomorrow, will I experience the same issues with that?

 

[ooga0341]

Pre-heating a mold shouldn't warp it. I have a toaster oven and put them in to warm them up in the winter. Try warming it up and shooting a few. A 3 oz injector should fill a 4 cavity stick bait mold. I have a 4 oz and have plenty left over. I also lube up my o-ring before 

I start shooting to make it run smoother. Basstackle has their injectors at a reduced price rn, if you want to get a 6oz. They're pretty good.

[Jig Man]

You might try using a Qtip and putting some cooking oil along the sides of the cavities.  Sometimes I have to do that with my baby brush hogs.