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Material compensation

The moulding company that I worked for is currently experiencing some problems. Moulded parts were rejected by the customer as black dots were found embedded in the part. The black dot will not cause any functional problems, only visual. The material manufacturer was informed, and they sent their engineer down to the plant. He checked the material and discovered black articles were mixed with the resin,thus causing contamination. The whole production was thus flawed. My company have since requested the manufacturer to compensate the material cost but have yet to receive a reply. The amount involved is rather hefty. since we do not have any experiences in handling matters of this kind, we would appreciate if anyone could shed some light on this and provide advice. Thank You.

Reply to
mowhoong
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What material is being molded? Regrind or virgin? Are all parts affected or just a percentage?

It is a common problem with some clear resins like polycarbonate, referred to as "black specs". Some material gets trapped within the mechanism inside the barrel where it stays for a long period of time; the material degrades and eventually chars. If it gets free, and mixes with the rest of the melt and enters the mold.

One of my customers once ask why my parts didn't have black specs like parts from their other suppliers. I replied that I sometimes did get black specs, but I didn't ship them. They are rejects.

Reply to
Billy Hiebert

your customer's rejection of the product is grounds for the resin supplier to compensate your company since their own engineer identified that the specks were in the supplied material. An easy case for a lawyer (should it come to that) if the situation is really as described.

John

Reply to
jriegle

It depends. Do you specify anything other than the manufacturer's standard grade? If a standard grade, is there a portion of their specification or other nomenclature that spells out the allowable contamination? Gels? Is this a new resin or vendor? How much historical leverage do you have with them? You could always go to a competitive grade (unless it's a medical application, then you are SOL as it's work with the vendor or lose your customer, for the most part.).

Reply to
L Alpert

Thank you all,

What is black spec? It is a common practice over here in Asia that the customer reserve the right to specifiy and select,

1) the type, 2) colour, 3) grade, 4) and price of the material from the supplier. The material supplier's dealings with the moulding company is isolated. The customer is not involved thereafter.

In this case, we used PC Virgin, colour: translucent green. Rejection rate: 45% We do not want to put this matter into a law case as it will affect relations between my moulding company and the material supplier itself.

Any advice?

Reply to
mowhoong

Black spots in the molded part...

that is normal, even in Europe if you are an "parts producer" it may be a bit other if you are an specialist...

even that is not strange...

The main problem if you will go the way trough the courts will be that:

The black spots was in the granuled material the engeneer of your supplier checked: was there a possibility that the material could be contaminated in your company? Second point: you have to check the material if it is the material you ordered...

if you juste compared the certificates and youz accepted this material then it will be hard to find a proof that this is not normal for that material... I had to learn that a diol could have an other functionality than two...

I asume that your company is a normal parts producer, are you supplied from the manufacturrer or from the dealer?

may be it will be worth to contact the manufacurer... from my experiance it is easier to solve such problems with the manufacturer than to work with the dealer... For some of my materials i have strange constellations: the quality is directly granted by he manufacturer, but i get it from several traders..

Michael I am not a bug I am a undocumented feature

Reply to
Michael Erwerle

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