How to design parts with Molded-In inserts?
How to design parts with Molded-In inserts?
(OP)
Hi,
I want to incorporate a Molded-In Insert to one of the products I'm working on, but this is my first go at it so I'm not sure how to design the area of the part where the insert will be embedded.
For the ultrasonic assembly inserts there are hole size recommendations from the manufacturer but for the molded-in i can't find anything specific, the only thing i managed to find is that the material outer diameter around the insert should be at least 1.5D (where D is the outer diameter of the insert) but not sure how accurate this info is.
And another thing is how to make the correct annotation for molded-in insert in a drawing.
Thanks.
I want to incorporate a Molded-In Insert to one of the products I'm working on, but this is my first go at it so I'm not sure how to design the area of the part where the insert will be embedded.
For the ultrasonic assembly inserts there are hole size recommendations from the manufacturer but for the molded-in i can't find anything specific, the only thing i managed to find is that the material outer diameter around the insert should be at least 1.5D (where D is the outer diameter of the insert) but not sure how accurate this info is.
And another thing is how to make the correct annotation for molded-in insert in a drawing.
Thanks.






RE: How to design parts with Molded-In inserts?
Andy Du
Supply Plastic Molds&Molding
Zhejiang IMF Plastic Solutions Co.,Ltd
http://www.injectionmoldfactory.com/
RE: How to design parts with Molded-In inserts?
RE: How to design parts with Molded-In inserts?
BUT, before you do anything else, call your molder and have a chat.
Using molded in inserts requires the operator to reach into the mold cavity, itself a violation of reasonable safety practices in many places, and individually place the inserts on some sort of pin to hold the insert, and be careful not to brush against the other dozen inserts already placed, so that an insert doesn't accidentally drop and lodge in the wrong place, causing expensive damage to the mold.
The time required to do all this manual labor in an awkward and dangerous location also adds random seconds to the mold's open time, which will affect part quality, because molds don't reach thermal equilibrium until a few cold cycles (and scrap parts) have been made.
I.e., chances are that your molder won't like using molded in inserts at all, so don't waste the time considering them.
Mike Halloran
Pembroke Pines, FL, USA
RE: How to design parts with Molded-In inserts?
One thing you need to do from a design stand point is either make sure the mold will close off tightly on the insert to prevent flash or make the parting line in a position where flash is not important. Worst case you hand trim flash, a very undesirable condition.
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RE: How to design parts with Molded-In inserts?
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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RE: How to design parts with Molded-In inserts?
Dan - Owner
http://www.Hi-TecDesigns.com
RE: How to design parts with Molded-In inserts?
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: How to design parts with Molded-In inserts?
http://www.stanleyengineeredfastening.com/brands/s...
RE: How to design parts with Molded-In inserts?
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: How to design parts with Molded-In inserts?
Mike Halloran
Pembroke Pines, FL, USA
RE: How to design parts with Molded-In inserts?
But i still cant find any reference on how to specify on a drawing the insert, because from the CAD point of view this is an assembly but theoretically the area without the insert will be a solid body without any holes as the polymer flow will fill the space that the insert would have occupied completely.
@Mike the final product will be a Mil. Spec. so no shortcuts
RE: How to design parts with Molded-In inserts?
... not _no_ hole.
For a molded-in insert, you specify the location of the thread in the insert, which will usually have a blind threaded hole within it, and you make sure the boss around the insert has wall thickness in accord with the manufacturer's recommendations, etc.
I haven't done a molded MIL-spec part; do they even allow non-replaceable inserts?
Mike Halloran
Pembroke Pines, FL, USA
RE: How to design parts with Molded-In inserts?
Btw when you said that i need to mark the location of the thread of the insert, you mean that i mark the center axis of the thread using center mark, dimensions and just annotate the thread using the standard ISO (for example) annotation?
RE: How to design parts with Molded-In inserts?
You also should annotate the callout or otherwise make the insert's presence clear, and show the insert's envelope as hidden lines in the drawing.
Mike Halloran
Pembroke Pines, FL, USA
RE: How to design parts with Molded-In inserts?
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.