Choosing a Chinese Mold builder 2

[mwalters]

Does anyone know of a decent checklist for qualifying a mold builder to fabricate molds for me? I am looking to get the same information from multiple shops in China to compare and try to choose a few good ones based on that information.

 

[patprimmer]

Do you know a good mould when you see it.

If so a trip to their facilities would be a good idea. Also talk to existing customers in developed countries.

The obvious things are

Grade and quality of steel.
Surface finish in important areas.
Quality and direction of polish re effect on ejection.
Position and number of ejector pin.
Position and number of cooling channels.
Size and placement of support pillars.
Size of back plate vs your pattern.
Is ejection compatible with your machine.
Parting line tolerance.
Allowance for shrinkage and ability to correct critical areas if need be.
Position of gates.
Size of runners and gates.
Design of runners and gates.
Position of vents.
Do vents have a small land then very big clear passages to atmosphere.
If there are side cores how do they blank of, is it adjustable and are the mechanisms robust.
If it has hot runners, how are they controlled. Where are the thermostats and elements.
Can he precisely reproduce the drawing in all areas. To what precision.

Regards

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[mwalters]

Thanks Pat, I appreciate the input. I am a former toolmaker and am not concerned with the specifics of a mold build per se. I am more interested in the procedures involved in building the mold. Ans was looking for a checklist or questionaire that encompassed items like this. For example:
Methods of
Indicating in a block
picking up electrodes for the EDM
Conveying information to the different departments
In process checking
As well as:
Where they purchase their tool steel
Where they heattreat their tool steel
Ability to plate or coat finished blocks


Again thanks for the input, and if anyone has knowledge of a checklist like this.

 

[53211]

I'm in mold polishing and texturizing business. I'm getting a lot of offers from china to make a molds for me, so I can give all this contacts to you. They use all steels available worldwide, but they can use their own steel if you do not clearly ask the steel from your preferable manufacturer. I saw some samples of molds where they "forgot" water line. You have to pay uppon reception of 50 samples. That quantity you can make without the water cooling of mold. Be carefull of mould counterfit.

 

[mwalters]

Thanks Pat,

I was a toolmaker for many years, so I do know a quality mold when I see one. I am looing more for a checklist of procedures and checks/balances that Asain suppliers might use to ensure consistancy in the quality of their work. Something I can rate them on against each other. I just returned from a week in China visiting tool building shops and had a makeshift checklist that I created. It worked OK, I was just looking for some input while I was creating it. If you are interested I have attached it here.

Matt

 

[jerrymould]

I am a plastic mold programm engineer in a mold company, I think you can find some documents such as TVR,3B,CPK to audit the company, you can check their ability in buliding the molds.