Re: [rp-ml] free STL Files and other (free) things we wish for in the new year

The volume (not the mass) of steel and polymer used annually in the world is roughly the same.
There are more metals and metal alloys than steel, of course. But there are also many more things
made out of neither (when you add the building industry in). So I think it's highly likely that, as
Marshal says, "Most products are not made from metal alloys."

As I look at the objects around me in my lab (which you'd expect to require more precision than
average) the only parts of any of them that need machining accuracy are bearing surfaces, and
locating holes and projections. The rest (the vast majority of their surface area) could be +/- 1mm
or more and still function just as well. So it certainly is the case that, "many parts of most
products do not need machined accuracy."

Best wishes

Adrian

Dr Adrian Bowyer
http://people.bath.ac.uk/ensab
http://reprap.org

G. Sachs wrote:
> Marshal Burns: "Most products are not made from metal alloys and many
> parts of most products do not need machined accuracy."
>
> Marshall, I was a big fan of yours in the early days of RP (and still
> have your book), but this just isn't right and I'm surprised that anyone
> involved with manufacturing (AM or otherwise) would make such a claim.
> More on this later however (as I have no time right now).
>
> G. Sachs
> Paradyme Systems
>
> ------------------------------------------------------------------------
> *From:* Marshall Burns <ListMail2@fabbers.com>
> *To:* RP-ML <rp-ml@rapid.lpt.fi>
> *Sent:* Fri, January 8, 2010 11:17:56 PM
> *Subject:* RE: [rp-ml] free STL Files and other (free) things we wish
> for in the new year
>
> Most products are not made from metal alloys and many parts of most
> products do not need machined accuracy.
>
>
>
>
>
>
>
>
>
> ------------------------------------------------------------------------
>
> *From:* owner-rp-ml@rapid.lpt.fi [mailto:owner-rp-ml@rapid.lpt.fi] *On
> Behalf Of *Tam
> *Sent:* Friday, January 08, 2010 18:06
> *To:* Elaine Hunt
> *Cc:* RP-ML
> *Subject:* Re: [rp-ml] free STL Files and other (free) things we wish
> for in the new year
>
>
>
> Elaine,
>
>
>
> Additive Rp has never attained the form (machined accuracy) or physical
> properties of industrial parts machined accurately from metal alloys.
>
>
>
> Happy New Year,
>
>
>
> Tom Richards, Metallurgist
>

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