Do-It Mud Bug 3.75" Dual Injection Problem. Another Vendors Mold?

[RSullivan]

I have a couple of single cavitiy 3.75" Mud Bugs.
When I inject them with a dual injector (Jacobs 'Pro' Machine)
1.) The bottom of the body is in fact my bottom color (Yea!).
2.) The legs and pincers on one side (the 'top' from the orientation of the mold) are the top color (Boo!).
2.) The legs and pincers on the other side (the 'bottom' from the orientation of the mold) are the bottom color (Boo!).

 

I understand the nuances of molds that do not do well with dual injection, and am assuming that the 3.75" single
cavity mud-bug is one of these.

Do others see this problem?

 

I am asking becuase I want to get a craw mold (minimum 3.75", maximum 4") that has at least 6 cavities.

1.) I am thinking of getting the six cavity 3.75" mud bug mold.
    Perhaps it does not exhibit the same issues that the single cavity mold seems to have?
    Anyone have experience with this mold?
2.) I am unable to find any 6 cavity or better craw molds in my desired size from the usual suspects
    (BassTackle, Do-It,...). Anyone know of another manuafacturers mold that fits this bill?

Thanks.

[Basseducer]

Have you asked the usual suspects if they will make you one?

[hpssports]

I'd have to see a picture to know what you're talking about. I shoot lots of 3.75 Mud Bugs in laminates & never had any problems. All are single cavity.

[RSullivan]

Thanks hpssports.
I do not have a camera (or cell phone) handy.
If you shoot laminates with the mold and have no problems then I have no idea what is going on.
To clarify (Without photo):
1.) Shoot the mold with white bottom black top.
2.) Lay the bait flat with the head pointing away from you.
3.) The pincer and legs on the right hand side are black.
4.) The pincer and legs on the left hand side are white.

I would think it is my Jacobs Pro machine but in the same session I shoot plenty of other molds
as laminates and they have no such problems:
- 5" 16 cavity Wutz-Its.
- 4" 4 cavity Wutz-Its.
- 3.5" and 4.5" Do-It swim shads (both thin and normal tails).
- Plenty of different manufacturers stick's
- A 10 cavity 2.5" caw mold (Basstackle). Its the only other craw mold I have.

None of these molds have problems as the Mud Bug does.

 

Thanks Bassducer.
I have recently asked Basstackle for a 10 cavity 5" stick.
They said they have no time right now for any custom work.
I suppose I will look at other manufacturers craws and if I find one I like I will give them a call.

[DaveMc1]

 

Thanks hpssports.

I do not have a camera (or cell phone) handy.

If you shoot laminates with the mold and have no problems then I have no idea what is going on.

To clarify (Without photo):

1.) Shoot the mold with white bottom black top.

2.) Lay the bait flat with the head pointing away from you.

3.) The pincer and legs on the right hand side are black.

4.) The pincer and legs on the left hand side are white.

I would think it is my Jacobs Pro machine but in the same session I shoot plenty of other molds

as laminates and they have no such problems:

- 5" 16 cavity Wutz-Its.

- 4" 4 cavity Wutz-Its.

- 3.5" and 4.5" Do-It swim shads (both thin and normal tails).

- Plenty of different manufacturers stick's

- A 10 cavity 2.5" caw mold (Basstackle). Its the only other craw mold I have.

None of these molds have problems as the Mud Bug does.

 

Thanks Bassducer.

I have recently asked Basstackle for a 10 cavity 5" stick.

They said they have no time right now for any custom work.

I suppose I will look at other manufacturers craws and if I find one I like I will give them a call.

 

 

It honestly sounds like you are orienting the mold under the press in the wrong direction. try spinning it 90* and see what happens. Without a picture that would be my only guess. 

 

 

 

*edit* if the body is laminated properly then you will have to play with your temperatures to get the laminate to come out right. 

Edited October 28, 2016 by DaveMc1

[hpssports]

Does it happen with both molds or just one? It sounds like the mold may not be petfectly straight when injecting. When you have small legs & slightly thicker claws like the mud bug it has to be perfectly straight when injecting. I may get one out of 50 come out similar to what you are describing but usually just a slightly thinner color on one side.

[Bassinfool]

As others have said, make sure the mold is oriented as perfectly as can be underneath the press before you shoot it. Another thing you may want to check is the temps of your plastics. They need to be within a few degrees of one another, the closer the better. Some molds can be tricky to laminate. I have a craw from Bob'a that is an absolute pain in the ass to the point I hand pour a belly and then inject.

[RSullivan]

Thanks Guys.

It happens on both molds.

I line the olds up with the injector with a carpenter square, so I am positive they are square to the nozzle.

 

I have looked closely at the molds and now and realized it is in fact the molds, specifically the hinges Do-It uses

on their molds.

The hinges where put on in a very sloppy manner. When closes and clamped the mold halves where not lined up correctly.

 

I removed the hinges and carefully lined the two halves up and clamped.

Though not perfect I can now shoot a satisfactory laminate.

 

Thanks for all the help.

[Frank]

How does a misaligned mold cause that type of problem with a laminate? If the colors are not 50-50 it's not the mold. Laminating is a flow/hydraulic process and viscosity of each color will make or break you. Lowering the heat will make it less likely to mix/swirl. How are you getting temp on your machine? And are they close to each other?

[RSullivan]

Thanks Frank.

I am not sure how the mold misalignment causes the laminating problem (I am not a hydrolic engineer).

But the fact is that the misalignment is causing the issue.

1.) I have two molds.

2.) With the hinges on they are both mis-alogned somewhere between 1/32nd and 1/16th.

3.) I have taken the hinges off of one of the molds.

4.) I align (carefully) and clamp the hingless molds. It is aligned.

5.) I close the hinged mold and clamp, it is not aligned.

6.) I have a jacobs Pro machine & two digital thermometers with probes. One on each tank.

7.) The temprature varies by 4 degrees.

8.) I shoot the molds.

9.) The molds without the hinge shoots well (a good laminate).

10.) The 'hinged' mold (which will not align correctly due to the 'bad' placement of the hinge) does not shoot the laminate well. It exibits the original problem I reported.

11.) I then took te hinge off of the 'bad' mold.

12.) Aligned carefully, clamped and shot it.

13.) This mold now shoots well (a good laminate).

 

With the hinges on the molds the 'bottom' of the molds where slightly (1/32nd - 1/16th) forward along the

horizontal plane than the 'Tops' of the molds. This meant that the 'sprue hole' in the mold was not a circle, but rather

two halves of a circle with one half being slightly offset (ahead of) from the other half.

 

I am pretty sure the mis-alignment was causing cavitation (i.e. 'swirl') in the mold.

 

 

This data of course is all imperical!

 

Thanks.

[Frank]

Ok well then the temps are within four degrees but what are they? A number value. Cause if they are 350 then a hair will make them mix. But if they are 300 it will take much more to make it mix. On the do it mold is there not a pin on the Sprue side? Of which would make it easy to see a misalignment that is that large? Without pictures it's real hard to tell.