Help please

[vlada101]

I read few post with this problem, and try to: heat mold and injector, colder plastic, slow and faster injection, keeping pressure (10 - 15 sec) .....
But I not solve the problem. Molds is costume made, maybe I have problem with mold ... on 3" sometimes have gap, but on 5" mold always    ... maybe I made too much vent on 5"  ....  does someone have any idea ?

this is 5" mold:










this is 3" mold:

[ctom]

Send the mold back and have the stringer channel cut out to at least 1/2". 5/8" on  bait that size would be better but you don't have that big of an issue. The tails seem to be filling out ok and your problem is that there isn't enough hot reserve plastic in that narrow stringer.

[vlada101]

you probably mean on this channel         :





I will send mold to correction, but think that channel can be max about 3/8"    ...  thanks for help, I will know for my next mold what size channel need to be ... bigger bait bigger channel 

[ctom]

Yes sir. Just looking at the mold you show I see no reason another pass thru the channel to get you a half inch isn't feasible.

I can almost assure you that given the bulk of that bait's body you are not getting , or supplying, enough hot plastic to allow the bait to pull in to fill the void created by cooling. That's a bulky body. The problem is that the narrower stringer cools faster than the body plastic.

[gone2long]

is it me those gates look way too small, being that narrow I think they are setting up before the cavity can pull any plastic in?

[pjmcla]

Nice looking bait.   I agree with both Ctom and gone2long.  The runner is small and the gate is as well.  If you just increase the runner without increasing the gate I am not sure that the problem will be resolved.  That is a very small gate, and I think the plastic is solidifying there first. 

[biglewers]

Who made that mold?

[vlada101]

Thanks for help, I talked with my mold maker and he will repair it tomorrow. He will cut 1/2"

It is custom mold in local shop

[MonteSS]

The runner does not have to be round. My best injecting mold is custum and has a square runner.



....Bill

[Frank]

is it me those gates look way too small, being that narrow I think they are setting up before the cavity can pull any plastic in?

Bingo this is more of a problem than the channel. Even if it is open more it will solidify at the gate first. Have him bump a ball mill in and get rid of the channel all together.

[MO QWACK]

Common mistake in mold making , the channel can't be to big but it sure can be to small, great looking baits! The mold maker did a great job other than the small channels but if your not familiar with the characteristics of plastics they wouldn't of known any better.  Hope he gets her opened up a little for you

[vlada101]

Problem is solved. Runner is bigger and baits is perfect now.
I will post pictures in a few days

Thanks for helping me

[pjmcla]

Great!  Glad to hear the mold is injecting as it should.  Now it is fish catching time.  It is very frustrating to have something you have worked at not do as it should.