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How is a mold grained?? 3

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Rostam

Automotive
Dec 25, 2002
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Dear all,

I want to know how a mold is grained, especially when the texture is complex like what we have on Peogeot 206 door panels,

Does anyone know any site or source who have any kind of information concerning the process of graining?

thanks
 
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Etching techniques can be used, and I do not know the details, but electro deposition can also be used. It produces extremely accurate replicas of the original pattern.
I have seen mould cavities from material deposited directly onto a pice of leather, with perfect reproduction of the leather surface.
I would have to look up some old literature to see who does it Regards
pat
 
Dear rostam
hi
I suggest that u visit mold-tech.com that have several branch in the world.
the method is simple @difficult.if u need more information let me know.

I have the experience on these type of the texture like that u need.because this type of texture is multi step.

be glad.
khoda hafez
 
Hello,

I have been directed to this forum by one of our customers. Our company's name is Akron Metal Etching located in Akron, Ohio USA. We specialize in mold texturing for industries of all types, but mainly the plastics industries. We have been texturing or graining molds since 1944. Generally,Akron Metal Etching does not do texturing for the automotive industry at this time, but our associates do.

The question you ask is quite complicated if you are asking for specific processing information that is generally considered proprietary. Many of the automotive grains are multiple levels of grains and require different combinations of patterns.

If you are trying to locate a source for a mold to be grained I believe I can be of assistance. What country are you located? Please feel free to visit our website, we are members of a group of texturing companies located in the U.S., Europe, South America named the Surface Etching Cooperation (SEC) with a website of with links to the members. If you have any problems contacting any one on the list, please feel free to contact me.
I believe our French member does work with Peugeot. Our European associates do a great deal of automotive graining.
I hope this is helpful to you.
Thanks,
Lee Eisinger
President
Akron Metal Etching Co.
463 Locust St.
Akron, OH 44307
 
I am not sure what detail you got on the actual process from the websites, but how they actually do it is to etch with acid.

The texture exist as standard negatives (as in photo negatives), these are positioned onto the mould serface and the acid is aplied. Time determines the depth of etch.

Obviously this is a very skilled and precise job, the peparation itself is very tedious and takes hours or days.

Texture repair is also an art.

Respect to those who can.
 
Wisconsin Engraving Company / UNITEX, located in New Berlin, Wisconsin does automotive texturing. We are also members of the SEC (Surface Etching Cooperation. We have the abilities of not only applying texture to molds with he acid ethc process, but also with many other techniques others do not use. We have been in business since 1925. Also, nobody's website will go into detail excatly how the process is done. Everybody has theer own technique and no one way is best. Every texture house has perfected their own way to suit the customer base they have. we serve not only the auot industry, but the the medical, aerospace, home goods, office products, military and many more.
 
We have a lot of molds which require surface structuring. We found the best method for our application is photochemical etching. A company specializing in this method is called "Hohenloher Formstruktur, Max-Eyth-Strasse 2, 74629 Pfedelbach, Germany". I don't know if they have a Website, but you can contact them at this address.
 
Dear Sir,

Check out
We are making tooling for several industries including auotmotive and plastic building materials, such as plastic siding. We have a unique patent process where we produce our tooling in a foundry with a ceramic cast-to-size technology. Our process is capable of achieving details that CANNOT be achieved through machining and etching.

Regards,
John Mandala
 
thanks to Chaving that I got the idea how surface texture is formed.
He says that "the texture exist as standard negatives (as in photo negatives), these are positioned onto the mould surface and the acid is aplied"

I would like to know how this photo negatives are positioned on to the mould surface.[\color]

The original texture on the photo negatives extends in x-y or z ? Are there some limitations on the curvature of the mould to be textured to avoid texture shape deformation- if the shape of the texture is subject to deformation as I think?[\color]

 
My info is way out of date and for a different application, but there used to be a technique of coating a surface with a photo sensitive coating, selectivly exposing to light. The light effected areas will harden and stick, but the shaded areas will wash off. The acid then has more access to the areas where the coating washed off.

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
 
quote "but there used to be a technique of coating a surface with a photo sensitive coating, selectivly exposing to light."

Pat, we have molds textured all the time, you are right. The process is nearly identical to the way printed circuit boards, silk screens for t-shirts, etc are made. As far as surfaces that can be textured, I haven't seen many that couldn't. The only time we have had trouble is on dis-similar materials, ie amp940 inserts vs aluminum core, or welded areas in aluminum, but most texture houses we deal with work around that and do a fine job. Typically we have found that max depth of texture is around .008".

We build a lot of blow mold tooling, one area that we keep the texture away from is the pinch edge, as it can undermine the integrity of the pinch edge.

Sincerely,



Jay Rogers
American Tool & Engineering, Inc.

Visit our website at:
 
Dear all

Since every mold texturing expert is here. I would like to ask if any one know where I can get some information regarding the texture patterns, in micro scale level. Some SEM pictures would be handy. I need to know the size of the pours and the pitch of the pours that are obtained by mold texturing.

Thank you
 
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