Aha, My memory was right here is the information i new was out there.
http://rapid.lpt.fi/rp-ml-1997/3010.html
Doug Groh
proy@chennai.tcs.co.in wrote:
> For all those folks who were interested :
>
> Motorola patent number : 5818005
> According to my (sadly neglected) notes, this patent is for making
> electrodes through isostatic pressing of graphite.
>
> I'll add a caveat from personal experience: its harder than it looks and
> getting the right binders is a pain(conductivity, viscosity.... its a
> minefield). Also, you'll have issues with modeling geometry.
>
> Before my research group dissolved, we were doing some wear analysis on
> these tools as well as on electrodes produced from electroplated copper
> shells. The copper shells behave far more predictably than compacted
> graphite. I could send along my research notes and comparisons for those
> who would like to continue down that path.
>
> I would consider Dr. Brent Stucker of the University of Rhode Island to be
> an authority on the subject of graphite-based EDM tooling. He has authored
> some fascinating work, including a study of relative tool wear ratios for
> different materials. Their "Zrykon" based solution looks most promising,
> although it is really not the "mouldable" solution that Rick was looking
> for when he started this thread.
>
> Adios!
>
> Peter
>
>
> Phil Dickens
> <pdickens@dmu To: proy@chennai.tcs.co.in, rp-ml@rapid.lpt.fi
> .ac.uk> cc:
> Subject: RE: Graphite powder
> 09/12/01
> 02:39 PM
>
>
>
> Rick,
> Sorry for late reply. I did get some verbal information on a mouldable
> electrode material around 1991. I eventually tracked it down to a company
> called Erodex here in the UK. http://www.erodex.com/main.htm
>
> However, by the time I had contacted them around 1994 they said that they
> no
> longer did the material and it was very difficult to get hard information.
> I
> believe the guy that used to run the company was most knowledgeable. If you
> have any luck I would be very interested.
>
> Regards
>
> Phill
>
> Prof. P. M. Dickens
> Dept. of Engineering & Technology
> De Montfort University
> The Gateway
> Leicester
> England LE1 9BH
>
> Tel: +44 (0)116 257 7689
> Fax: +44 (0)116 257 7025
> Mobile: +44 (0)7768 827039
> Email: pdickens@dmu.ac.uk
> www.rmg.dmu.ac.uk
>
> -----Original Message-----
> From: proy@chennai.tcs.co.in [mailto:proy@chennai.tcs.co.in]
> Sent: 12 September 2001 04:44
> To: rp-ml@rapid.lpt.fi
> Subject: Re: Graphite powder
>
> Rick,
>
> My research team worked on rapid tooling EDM electrodes for over a year.
> We tried compaction methods for creating EDM tools from graphite powder,
> with a little bit of polyvinyl alcohol thrown in as binder. Motorola does
> hold a patent for a similar process (I'll send you the patent number if I
> can lay my hands on it...).
>
> Adios!
>
> Peter
>
> <snip>
> Dear List,
> Is it possible to mix graphite powder with any electric
> conductive bonding material ? So that we can cast any shape out of this
> powder and use it as an EDM electrode just an idea to get your views.
>
> Regards,
> Rick
> <snip>
>
> For more information about the rp-ml, see http://rapid.lpt.fi/rp-ml/
>
> For more information about the rp-ml, see http://rapid.lpt.fi/rp-ml/
For more information about the rp-ml, see http://rapid.lpt.fi/rp-ml/
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