Can anyone fill in on the do's and dont's in mold making to ensure surefire success, especially in the area where parts dimensions are affected by factors other than shrinkage such as deflection or uneven wall thickness or flexing due to geometry.I would also like everyone to focus on do's and dont's for parts with very close tolerances and how to achieve them.

Hi Jitendra glad to introduce my self, I am sanjv Owning a SSI Unit in Coimbatore, like this discussion, we had exprienced short filling in Thin wall Container's, Being Mould Found ok in alingment we observed low wall thicknees at on side.
Do's- Provide a rigid Taper lock-(Core Holder with Core, Core With Cavity)
Do's- Provide male radius slightly bigger than Female.
Do's- Provide Sufficient airvents
Do's- Allow Pillar and Bush To Guide First

Dont's- Never let Air ejection to project more than 0.05mm, from the matching surface

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Hello Jitendra, It is not necessary to follow Do's and Don'ts for such things. Flexing , uneven wall thickness can be due to many reasons. It is necessary to study individual case than generalizing.The automotive battery box moulds are a good example. In case of achieving critical dimensions on plastics I would suggest that you keep the mould cavity or core dimension on a correctable so that without discarding the insert or die you can bring it to the mid tolerance of the component.

Hi Godfrey,
The mantra then is , stay steel safe and correct after first trials.I think the more the experience the closer one gets to the final size.I remember a plastic part somewhat like a small push fitting with two wings with a control dimension on wingtips at 16mm +/- 0.05. The tips would collapse a good 1mm after injection moulding and took us over four iterations to achieve the tolerance required.The do's would be to keep correctable inserts and be able to predict collapse.
This is the sort of part that I would like to come closer to in the first attempt.