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brentb
1st December 2011, 05:32 AM
How would you validate the process for micro-molded parts?

Keep on Molding!

brent

pjhall
1st December 2011, 09:19 PM
I think most of the "Scientific Molding" principles go out of the window especially if you are using some of the exotic medical resins that cost $2200 a lb!!! Good question though. I look forward to replies.

Suhas
5th December 2011, 02:09 PM
PJ is right with a minor correction. Most of the Scientific Molding principles are mostly valid but the procedures go out of the window. For example, there will be gate seal but we probably do not have the accuracy of say ..... steps of 0.1 seconds to measure the part weight variation of 0.0001 grams consistently. Consistently is the key word here. So it is a little difficult.
Why do we do a validation? - to make parts to spec consistently and to find the extent of the dimensional process windows. So to answer the Q about validation, I would first list the various factors that in your experience have made an impact on the quality of the part. Example - Mold , Machine, Molding parameters, etc. Then come up with your own procedure and DOE steps to perform a validation.
Going back to PJ's comment -
Step 1: Viscosity Study is out
Step 2: Cavity balance - Can be done
Step 3: Pressure drop is probably out
Step 4: Process Window - can be done
Step 5: Gate Seal is probably out
Step 6: Cooling study is also probably out (since I think cooling time probably does not have much of an impact)
Please correct me if I am wrong.

Suhas

pjhall
7th December 2011, 09:45 PM
Yes, I stand corrected. I did mean the procedures, especially when using really expensive material.

armold
30th January 2013, 07:24 AM
I am not sure but i guess there is a method of validating the process for micro molded parts. However, I have not done it yet.
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