impossible to mold?
impossible to mold?
(OP)
I designed this part for a toy.

It snaps into a wooden panel and has a cross hole through which you can attach a bell.
I know this would be complicated to mold but is it impossible? That is the opinion of one of my suppliers.
Thanks.

It snaps into a wooden panel and has a cross hole through which you can attach a bell.
I know this would be complicated to mold but is it impossible? That is the opinion of one of my suppliers.
Thanks.






RE: impossible to mold?
The two side pulls limit you to a single cavity, which might keep the unit price too high for a high volume toy. Maybe that's what your supplier meant.
It will have flash problems, and be expensive to deburr.
Mike Halloran
Pembroke Pines, FL, USA
RE: impossible to mold?
From the drawing it looks difficult, but definitely doable.
I see four side cores with the current design, but that could easily be reduced to two if the slots are modified slightly to match line of draw of the side cores for the holes.
The tooling will be expensive.
Multiple cavities are possible, but will be very expensive.
Draft angles are not specified. Parallel pins for some long holes may be impossible.
Regards
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RE: impossible to mold?
RE: impossible to mold?
You need to talk to your supplier about your functional needs in the part and how your design can be changed to make it more manufacturable. Since this part looks like it is noncosmetic, I'm sure you can get the same function without the tooling headaches.
-b
RE: impossible to mold?
Could you mold the part without the cross holes and add them via a secondary drilling operation?
RE: impossible to mold?
Although it is not entirely clear, I see the bell pivot hole with the big boss as having the big diameter on the outside, so the side core can be extracted.
The slots can be done vertically.
The undercuts for the snap fits can be done vertically from the opposite side to the slots.
It will require a very good fit and good blank offs to prevent flash. It will be difficult to eject and will require good draft angles and line of draw polishing and stripper plate or at least sleeve ejectors to get it off the pins.
I would tend to think that the core should be the fixed half, and the cavity should consist of two blocks that split to pull the side cores and release the part from the cavity.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: impossible to mold?
Not only do you know a lot but you share your knowledge as well. You have been a big help.
Thanks,
DD
RE: impossible to mold?
Pat,
Take a look at the 3D view in the top right corner, and you can see that the small hole is near the surface. Either you've got thick walls or a difficult core out.
-b
RE: impossible to mold?
As everything else looks good from section thickness point of view, I do wonder why the section is so thick there.
There is no view that shows that boss from the inside, so we are guessing.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: impossible to mold?
Many of the posters make valid points but your part is very mold-able. It's just a matter of how much you want to spend on your mold. If you take the time to work with your reputable mold maker or mold designer before you are under the gun, they can recommend some minor improvements to save on your tooling.
RE: impossible to mold?
The PL will be stepped of course with 2 side slides that would be below the PL(buried).
RE: impossible to mold?
Work with your mould maker to define the parting line and do the drafting in your model to ensure design functionality.
Mauricio Benavides
Injecnet Solution Inc
www.injecneering.com
RE: impossible to mold?
Mauricio Benavides
Injecnet Solution Inc
www.injecneering.com