air pocket question

[jeffhill]

I just got a new jointed swim jerk mold from bass tackle and I keep getting an air bubble in the head section on about 75% of my baits. :'( I don't have this problem with any of my other molds. Does anyone have any suggestions on what I might be doing wrong.

Thanks, Jeff

[MarkGuru]

Do you have a picture of the mold?

Basic stuff:

Room temp
molds
injector


I do not follow the you tube vids

First injector fill
Let my injector set a bit in the hot plastic, then fill it up, let it set again
not long.
Then inject the mold.

If you pre-heat the mold or the injector you will get bubbles.

Also... Do not clamp the mold or tighten too tight this will trap air.

Tighten the front of the mold, just a little bit more than the back, this will allow a good inject with natural ventilation.

Work with it until you get it correct.

Oh, check the temp of the plastic, I used a cheap electric temp thing from target a couple of times, until I had a little mist off the plastic.

Around 350 degrees to 360 F, get it a little hotter the first time think I shoot at 340 after that.

Have re-heated many times and never burnt to mess up the color, this you have to work with.

Hope this helps

Mark

[Jason]

I just got a new jointed swim jerk mold from bass tackle and I keep getting an air bubble in the head section on about 75% of my baits. :'( I don't have this problem with any of my other molds. Does anyone have any suggestions on what I might be doing wrong.

Thanks, Jeff

Pics would help but if it's a round hole right in the middle it's probably because you are running out of plastic and it is sucking in air.  Try pouring / injecting the bait again and topping it off as long as it is pulling down (the plastic is shrinking) - maybe 20 - 30 seconds depending on the diameter of the bait.

If this doesn't make sense just give me a call and I can talk you through it easier.

Tight lines,

Jason

[ghostbaits]

Try pouring / injecting the bait again and topping it off as long as it is pulling down (the plastic is shrinking) - maybe 20 - 30 seconds depending on the diameter of the bait.

Gotta be it Jason. Especially if it is the bait(s) closest to the injecion port/sprue.

Jim

[jeffhill]

Thanks guys, I held pressure on the mold for 30 seconds or so after the shot and it seems to have cured the problem. I don't know why I've never had this problem with any of my other molds before but it's working now. Thanks a lot, I don't know what I would do without your help.

Jeff