RE: Much (nice) talk about the Z-stuff, BUT ......

From: Tom Clay (
Date: Fri Jan 14 2000 - 16:56:49 EET

Alex and friends-

Just a point of clarification to add to this discussion...

Z Corporation has learned from our customers that many users recycle zp11
(starch) and zp100 (plaster) powder systems with excellent results. We
encourage their efforts. As Alex points out, most users can retain and
reuse nearly all of the powder left over after the part is produced. Our
testing does suggest, however, that part quality will be affected if powder
is recycled indefinitely, and we recommend introducing fresh powder

If our users recycle the powder as we recommend, our material costs become
less than $0.40 per cubic inch of finished part in zp11 powder and less than
$1 per cubic inch of finished part in zp100 powder, which we believe
presents unrivaled value to our customers.


Tom Clay
Z Corporation

> -----Original Message-----
> From: Alex Salvi [SMTP:ASalvi@MMCCINC.COM]
> Sent: Friday, January 14, 2000 8:35 AM
> To: Rapid Prototyping Mailing List (E-mail)
> Subject: RE: Much (nice) talk about the Z-stuff, BUT ......
> Have you noticed how regular deskjet printer manufacturers make their
> money? Say for example Canon. They will sell a printer for $80. You know
> that the work they put into it is not worth $80. So how do they make all
> the money? Answer: Supplies. They sell you an ink cartridge for $35.
> Similarly zcorp sells you a comparatively cheap machine and then charges
> premium on the supplies. In fact they tell you that you should not reuse
> the powder at all... Personally I reused almost all of the ZP11 material
> succesfully, I only threw away about .25" of powder that was around the
> printed parts (if you have read my previous emails you will have noticed
> that we print ceramics now, but it's the same story with reusing the
> powder). 
> In any case, wether you reuse your powder or not, you might want to take a
> look at the nasa rp site, they did a nice study on six machines and
> evaluated all the costs of operating the machines, including materials.
> You can download this study at http ://
> <>  
> I don't know much about all the various rapid prototyping machines. The
> Z402 is probably not the best out there today and the materials are not
> the cheapest, but it does what I need it to do for now. The only problem I
> have is that my customers always want a part that is at least 1/2" larger
> than the print bed.
> By the way does anyone know what rp has the largest print bed?
> Alex
> -----Original Message-----
> From: Jorn Berends []
> Sent: Friday, January 14, 2000 3:38 AM
> To: RP mailinglist
> Subject: Much (nice) talk about the Z-stuff, BUT ......
> Much talk about the Z-stuff, interesting also, but ....
> I was told that a maximum of 50% 'used-powder' can be mixed to new
> powder in order to get a reasonable quality product. When you have to
> build a small part of let's say 1x1x1", a lot of powder is spread needless
> in the part-volumebox. For as a general productvolume will never exceed a
> volume of let's say more than 25% of the total buildbox-volume of the
> Z-machine, a lot of material will be lost, or not be re-useable. Ain't
> this a big disadvantage of this system. The Z-machine is supposed to make
> 3d-parts cost-effycient (cheap in other words). For building such a small
> part the materialcost of the lost powder weighs heavy on the part-price.
> Am I wrong (?), or are there other methods used to save
> build-materials? (what does the material cost?) To build price-effective
> parts, we bought a Genisys machine some time ago; I think that this
> material-item is a big advantage of this G-FDM system. (But I have an open
> mind for someone who can convince me that I'm wrong!)
> Concerning speed, I have never had a customer who had a problem with
> a deliverytime of 24 hours, so speed is a minor aspect (or are you going
> out of your bed three times a night to take out parts and restart the
> machine) ....
> Thank your future reply on above, kind regards,
> Jorn Berends
> JB Ventures BV
> Bedrijvenpark Twente 165c
> NL - 7602 KE  Almelo  (the Netherlands)

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