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D2nc software announcement

Graham Hollis
 

Earlier this week I launched a new software product for CNC enthusiasts on
the Mach3 group. For those that don't subscribe there or may have missed it
here are the details.

I created a utility which runs from within Mach3, or as a standalone
program, for generating gcode in the shop. While I don't classify it as a
cad/cam program, it performs the same function for simple shapes. In that
regard, it is more like the Mach3 wizards but without the limitation of
pre-defined shapes.

Shapes are described using a Shape Description Language and then converted
to gcode. More information can be found on my web site at www.d2nc.com along
with the fully functional program. After 30 days it requires a license key
to generate gcode.

Thanks,
Graham Hollis
www.d2nc.com
Re: Open (i think) design for a parallel robot (reprap may be interested)

Carl Mikkelsen
 

Mike,

I've had pictures up for a long time. Most of the pics are of the
first machine. You've probably looked at it -- I saw my URL go past
as part of this thread. Here is a place to start:


There are some pictures of components of the second machine, but not
much of the whole thing. Maybe this weekend I'll take some more.

Constructing the second machine was greatly slowed by a lack of time,
and a general need to live life. The second machine is operating now, though.

First machine was "bluemonster", since it was painted blue. At my
wife's suggestion, the new machine is called "newmonster".

After I started the second machine, I got a lathe which offered many
kinds of distraction. Unfortunately, I got the lathe after I had
done all the work for which a lathe was suited.

I'm adding a "seventh" axis now, in the form of a rotary table and
tailstock. This will let me make cylindrical parts. Although I
really good hexapod might be able to machine all surfaces of a
vertical cylinder, I dont' end up with a large enough working volume
to do everything I'd like when the pitch and roll axes are set to large angles.

-- Carl

At 03:07 PM 9/1/2006, Mike Pogue wrote:

Cool! Could you post some pics somewhere?

Mike

Carl Mikkelsen wrote:
Someone in this thread suggested that a hexapod would be difficult
for homebrew construction. I built my hexapod (two now) because it
was easier to homebrew.

Why is it easier?

For me, it was easier because:

1) no large cast parts are required
2) no precision flat surfaces. No scraping required.
3) there is much similarity between parts. You need six legs --
all the same.
4) it is not necessary to home-manufacture any precision parts that
move against each other. No matter if you use threaded rod or ball
screws, the only parts that slide against each other are the screws
and matching nuts.
5) the emphasis is on the control system (software and electronics),
rather then the mechanical implementation. I have better tools for
compiling code and making PC boards than I do for making metal parts
(which is part of why I want a machine in the first place).

-- Carl

At 12:42 PM 9/1/2006, Ron Yost wrote:


Be careful about dismissing something as a toy, history is
littered with the
remains of those who made that mistake, from steam shovel makers about
hydraulic diggers, to mainframe computer makers about personal computers.
Tony
Too true! I apologize if I came off that way. It was not my intention to
be dismissive. I worded it very badly, it seems. And I'm sorry.

Thank You all for your indulgence and thoughtful responses! Education
is always a good thing. Even one at a time. :)

Best of luck in your endeavors!!! And, thank you again!

Ron Yost
Re: nice servos from plotter

 

No, HERE's the link:

Time for a weekend of woodworking and barbequed dead things, I think. Later.

On 9/1/06, Dennis Schmitz <denschmitz@...> wrote:
Normally, I just go to the manufacturer's website. Unless the motors
are truly ancient, they usually have a manual online. The one I had
trouble with was manufactured by Oriental Motors under an OEM contract
and they refused to tell me any of the specs (the only reason I could
think of was that the OEM wanted to lock out end users from repairing
their own machines.)

Here's a link to a guide about how to figure out a stepper wires.

On 9/1/06, Andy Wander <awander@...> wrote:

Did you have any problems deciphering the wiring to the encoders and the
motors?(I assume the motors are just 2 wires, and the encoders are....?)
Re: nice servos from plotter

 

Normally, I just go to the manufacturer's website. Unless the motors
are truly ancient, they usually have a manual online. The one I had
trouble with was manufactured by Oriental Motors under an OEM contract
and they refused to tell me any of the specs (the only reason I could
think of was that the OEM wanted to lock out end users from repairing
their own machines.)

Here's a link to a guide about how to figure out a stepper wires.

On 9/1/06, Andy Wander <awander@...> wrote:

Did you have any problems deciphering the wiring to the encoders and the
motors?(I assume the motors are just 2 wires, and the encoders are....?)
Re: nice servos from plotter

Andy Wander
 

It's a D-size plotter.

I am wondering what to do with it, but it is too cool not to use for
something.

________________________________________
Andy Wander

-----Original Message-----
From: CAD_CAM_EDM_DRO@...
[mailto:CAD_CAM_EDM_DRO@...] On Behalf Of skykotech
Sent: Friday, September 01, 2006 3:03 PM
To: CAD_CAM_EDM_DRO@...
Subject: [CAD_CAM_EDM_DRO] Re: nice servos from plotter

No, I didn't have any problems with the encoder wiring. The ground
pin was easy to find as it was connected to the ground plane and
thus all the mounting screws. I guessed that power would be +5
volts, and since there was a pin with a larger trace which was
routed to several chips, I assumed that to be power. I guessed on
channel A and channel B, and of course got them wrong :-) but that
hurts nothing..just swap them.

The motor is DC and only has 2 power wires, red and black. Bog
simple!

What does the 4699A look like? Is it a A size or one of the large D
or E size?



This communication including any attachments, are intended
for the exclusive use of the addressee(s) and contains
confidential or copyrighted materials. Duplication,
distribution or reproduction is strictly prohibited by law
without written permission of Verrex
Re: Open (i think) design for a parallel robot (reprap may be interested)

Mike Pogue
 

Cool! Could you post some pics somewhere?

Mike

Carl Mikkelsen wrote:

Someone in this thread suggested that a hexapod would be difficult for homebrew construction. I built my hexapod (two now) because it was easier to homebrew.
Why is it easier?
For me, it was easier because:
1) no large cast parts are required
2) no precision flat surfaces. No scraping required.
3) there is much similarity between parts. You need six legs -- all the same.
4) it is not necessary to home-manufacture any precision parts that move against each other. No matter if you use threaded rod or ball screws, the only parts that slide against each other are the screws and matching nuts.
5) the emphasis is on the control system (software and electronics), rather then the mechanical implementation. I have better tools for compiling code and making PC boards than I do for making metal parts (which is part of why I want a machine in the first place).
-- Carl
At 12:42 PM 9/1/2006, Ron Yost wrote:

Be careful about dismissing something as a toy, history is littered with the
remains of those who made that mistake, from steam shovel makers about
hydraulic diggers, to mainframe computer makers about personal computers.
Tony
Too true! I apologize if I came off that way. It was not my intention to
be dismissive. I worded it very badly, it seems. And I'm sorry.

Thank You all for your indulgence and thoughtful responses! Education
is always a good thing. Even one at a time. :)

Best of luck in your endeavors!!! And, thank you again!

Ron Yost
Re: nice servos from plotter

 

No, I didn't have any problems with the encoder wiring. The ground
pin was easy to find as it was connected to the ground plane and
thus all the mounting screws. I guessed that power would be +5
volts, and since there was a pin with a larger trace which was
routed to several chips, I assumed that to be power. I guessed on
channel A and channel B, and of course got them wrong :-) but that
hurts nothing..just swap them.

The motor is DC and only has 2 power wires, red and black. Bog
simple!

What does the 4699A look like? Is it a A size or one of the large D
or E size?



Rick:

I have a 4699A hp plotter that doesn't work, that somebody trash-
picked
and gave to me. I want to start fooling around with it and see if
I can
make something useful out of it.

Did you have any problems deciphering the wiring to the encoders
and the
motors?(I assume the motors are just 2 wires, and the encoders
are....?)
Re: Open (i think) design for a parallel robot (reprap may be interested)

Carl Mikkelsen
 

Someone in this thread suggested that a hexapod would be difficult
for homebrew construction. I built my hexapod (two now) because it
was easier to homebrew.

Why is it easier?

For me, it was easier because:

1) no large cast parts are required
2) no precision flat surfaces. No scraping required.
3) there is much similarity between parts. You need six legs -- all the same.
4) it is not necessary to home-manufacture any precision parts that
move against each other. No matter if you use threaded rod or ball
screws, the only parts that slide against each other are the screws
and matching nuts.
5) the emphasis is on the control system (software and electronics),
rather then the mechanical implementation. I have better tools for
compiling code and making PC boards than I do for making metal parts
(which is part of why I want a machine in the first place).

-- Carl

At 12:42 PM 9/1/2006, Ron Yost wrote:

Be careful about dismissing something as a toy, history is littered with the
remains of those who made that mistake, from steam shovel makers about
hydraulic diggers, to mainframe computer makers about personal computers.
Tony
Too true! I apologize if I came off that way. It was not my intention to
be dismissive. I worded it very badly, it seems. And I'm sorry.

Thank You all for your indulgence and thoughtful responses! Education
is always a good thing. Even one at a time. :)

Best of luck in your endeavors!!! And, thank you again!

Ron Yost
Now for a change of pace: PlasmaCAM

 

All of this talk of water jet cutters and occasionally lasers led me
to this website.



Apparently you're supposed to buy your own plasma torch, but in any
case, it's a very spartan design of an xy table with a little bit of
z. They claim accuracy of 0.0005 in the xy, making me curious how they
built the actuators and bearings. Getting both ends to move together
on the first axis seems an issue -- maybe a rod with rack and pinion
at both ends would work if you could get rid of the backlash.

Notice that almost all the structural elements are bent sheet metal
and the cable holder saves a bunch of expense from using a flexible
wiring channel.

A small handheld plasma torch is a bit expensive at $1500, but it's
way cheaper than a laser.
Re: nice servos from plotter

Andy Wander
 

Rick:

I have a 4699A hp plotter that doesn't work, that somebody trash-picked
and gave to me. I want to start fooling around with it and see if I can
make something useful out of it.

Did you have any problems deciphering the wiring to the encoders and the
motors?(I assume the motors are just 2 wires, and the encoders are....?)

________________________________________
Andy Wander

-----Original Message-----
From: CAD_CAM_EDM_DRO@...
[mailto:CAD_CAM_EDM_DRO@...] On Behalf Of skykotech
Sent: Thursday, August 31, 2006 10:10 PM
To: CAD_CAM_EDM_DRO@...
Subject: [CAD_CAM_EDM_DRO] nice servos from plotter

Hi guys,

Haven't posted in awhile...been busy this summer with other
projects. I just disassembled a HP7550A pen plotter and cut down
the carriage to make a lightweight Y axis for a laser engraver. The
plotter was all of $15 purchased locally, and includes two very nice
pittman servos with encoders. They are pretty small, but actually
have quite a bit of power. Of course there are little forces with a
flying lens laser engraver, but perhaps they could be used to move a
camera for a 3D digitizer or something similar. I am driving them
with a Pixie P100 step/dir to analog converter (www.skyko.com)
hooked to an Advanced Motion Controls 12A8 brush amplifier (a bit
overkill).

Here is a quick video of the carriage moving at 2640IPM running on
Mach3. The carriage actually takes 4000 steps to move 1 inch, but I
have set the step multiply in the Pixie P100 to 4x. With Mach3
outputting a max of around 45khz, this gives me 1000dpi resolution
and the 2640IPM travel speed (fairly fast, no?)



-Rick


This communication including any attachments, are intended
for the exclusive use of the addressee(s) and contains
confidential or copyrighted materials. Duplication,
distribution or reproduction is strictly prohibited by law
without written permission of Verrex
Re: Open (i think) design for a parallel robot (reprap may be interested)

 

Ron Yost wrote:

Is it just me, or are there others wondering what these machines are
intended for?

How can the apparent goal of self-replication (of a largely metalic
machine) be accomplished by squirting layers of hot-melt plastics? Or carving foam??

They're fascinating to watch .. but other than rapid-prototyping (making
plastic
models of things), and/or as a conceptual challenge, of what utility are they
for getting -real work- done???
For some, it may be an intellectual challenge, only. For modelmakers and RC airplane
folks, small lightweight parts may be perfecly usable as is. And, for people with the
ability to do lost-wax casting, these parts may be the mold patterns for either sand,
lost wax or investment casting.

Things have to be really beefy to do heavy, yet precise, work in steel, and I don't see how eliminating mass is going to work at all for us home-
shop types doing metal. Plastic bearings wouldn't last long at all, either.

Yes, and it is with constant dismay that I see yet another newbie coming in and
saying he's going to build a machine with 1/2" Thompson shafting that will mill steel
blocks a foot on a side.

Yes, I know a tripod is a very strong structure. And I do get the concept of the things. But, there has to be mass somewhere, doesn't there?? How can
a decent spindle holding real milling cutters hang off spindly legs?? Or
is there a 'scale' thing here I'm not getting?

Well, mostly. Mass is a cop-out when sufficient stiffness can't be obtained.
Really, stiffness is the first goal. But, looking at a Bridgeport machine, for instance,
it should be pretty obvious that spindly struts can't maintain the stiffness required
unless things are quite overconstrained. That's why the 6 legs of the Stewart platform
help, when the adjacent struts are loaded against each other. Secondly, it is rarely
necessary to use 1" diameter end mills (and larger) on smaller parts. The only real
requirement for them is when reaching DEEP into a cavity. A smaller cutting tool
spinning much faster requires much less stiffness of the machine.
But, if you want smooth cut surfaces on hard materials, spindly legs are not likely
to help achieve that goal.

Jon
Re: Open (i think) design for a parallel robot (reprap may be interested)

 

Be careful about dismissing something as a toy, history is littered with the
remains of those who made that mistake, from steam shovel makers about
hydraulic diggers, to mainframe computer makers about personal computers.
Tony
Too true! I apologize if I came off that way. It was not my intention to
be dismissive. I worded it very badly, it seems. And I'm sorry.

Thank You all for your indulgence and thoughtful responses! Education
is always a good thing. Even one at a time. :)

Best of luck in your endeavors!!! And, thank you again!

Ron Yost
Re: water jet cam

Les Newell
 

Hi John,

Unfortunately SheetCam can't do that. There is a text wizard available for Mach that does pretty much what you want. Alternatively have a look at DesignCad Express from <>. It has built in single-line fonts. You can then use SheetCam or Lazycam to convert the drawings to g-code.

Les


John Dammeyer wrote:

Hi Les,
So my question is, can SheetCAM create letters from a DXF file where the
tool is an engraving bit and the tool path is the centre of the letter. I
need speed here. I currently use a hand held vibratory engraver and can
whip out 12 sets of two digit serial #s very quickly and the numbers are
quite legible. I don't want the G-Code to follow the outline of a letter. Does this make sense?
John Dammeyer
Re: water jet cam

 

Hi Les,

Thanks for the info. I have a little project that requires MACH2/3 to
engrave a serial # onto a PCB board. The system will work as follows:

MACH moves table to the first circuit board on a panel and asserts an output
and then waits for one of a couple of inputs. The output triggers the
programmer to program the PIC micro-controller.

If programming was successful, the OK line is asserted and MACH moves the Z
axis down and up to have a rod push the button on the board for testing. It
then again waits for the OK line or NOTOK line.

When OK happens it calls a subroutine file that has been created by the
programmer code. This is a concatenation of G-Code files each containing
one letter or number. (0..9, A..F). The programmer just creates the serial
# file which is read in by MACH which knows where on the board to engrave
the serial #s.

Now for everything except the engraving I could have written a simple
program to just do the positioning and programming. MACH is kind of
overkill for this application. But engraving letters by sending G-Codes
seemed to be the easy way.

So my question is, can SheetCAM create letters from a DXF file where the
tool is an engraving bit and the tool path is the centre of the letter. I
need speed here. I currently use a hand held vibratory engraver and can
whip out 12 sets of two digit serial #s very quickly and the numbers are
quite legible. I don't want the G-Code to follow the outline of a letter.

Does this make sense?

John Dammeyer



Wireless CAN with the CANRF module now available.

Automation Artisans Inc.
Ph. 1 250 544 4950

-----Original Message-----
From: CAD_CAM_EDM_DRO@...
[mailto:CAD_CAM_EDM_DRO@...] On Behalf Of Les Newell
Sent: Friday, September 01, 2006 8:34 AM
To: CAD_CAM_EDM_DRO@...
Subject: Re: [CAD_CAM_EDM_DRO] Re: water jet cam


Hi John,

SheetCam is a CAM package so it takes your drawing, works out the
toolpaths, cut order etc then generates G-code for Mach to cut.

For instance say you draw a 1" square. You could load that
drawing into
Mach and cut it but Mach would follow the lines exactly so the part
would come out undersized by the cutter diameter. SheetCam
knows about
this so it would increase the size of the square to allow for
the cutter
diameter. Your part would now come out exactly to size.

Les


John Dammeyer wrote:
I See from the web site that the registration tab can
include MACH2. So why
would someone need sheetcam if they have MACH2/3?

John Dammeyer

Subject: Re: [CAD_CAM_EDM_DRO] Re: water jet cam


SheetCam <www.sheetcam.com> can do this at a much lower
price. I can
write a post processor for you that will slow down to a preset
percentage of the normal feed rate on arcs. The post could even be
configured to slow down more for tighter arcs.

Les

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If you wish to post on unlimited OT subjects goto:
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I consider
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Re: water jet cam

Les Newell
 

Hi John,

SheetCam is a CAM package so it takes your drawing, works out the toolpaths, cut order etc then generates G-code for Mach to cut.

For instance say you draw a 1" square. You could load that drawing into Mach and cut it but Mach would follow the lines exactly so the part would come out undersized by the cutter diameter. SheetCam knows about this so it would increase the size of the square to allow for the cutter diameter. Your part would now come out exactly to size.

Les


John Dammeyer wrote:

I See from the web site that the registration tab can include MACH2. So why
would someone need sheetcam if they have MACH2/3?
John Dammeyer

Subject: Re: [CAD_CAM_EDM_DRO] Re: water jet cam


SheetCam <www.sheetcam.com> can do this at a much lower price. I can write a post processor for you that will slow down to a preset percentage of the normal feed rate on arcs. The post could even be configured to slow down more for tighter arcs.

Les
Re: water jet cam

 

I See from the web site that the registration tab can include MACH2. So why
would someone need sheetcam if they have MACH2/3?

John Dammeyer

Subject: Re: [CAD_CAM_EDM_DRO] Re: water jet cam


SheetCam <www.sheetcam.com> can do this at a much lower price. I can
write a post processor for you that will slow down to a preset
percentage of the normal feed rate on arcs. The post could even be
configured to slow down more for tighter arcs.

Les




afogassa wrote:

Hi Peter,
I do have deskcnc and it's good enough for this, but water jets
needs a good cam that can look way ahead and predicts what
is going
to happen and than starts to adjust the feed rate before
it gets to
a corner or radius to compensate for Jet lag doing that manualy
would be a pain if not impossible.
Got a quote from PEPs and it runs at 10K US$ (ouch !!)
I've being thinking about getting a working G code, than work this
out on excel to adjust the feed rate.

Addresses:
FAQ:
FILES:
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Subscribe: CAD_CAM_EDM_DRO-subscribe@...
Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@...
List owner: CAD_CAM_EDM_DRO-owner@...,
wanliker@..., timg@...
Moderator: pentam@... indigo_red@...
davemucha@... [Moderators]
URL to this group:

OFF Topic POSTS: General Machining
If you wish to post on unlimited OT subjects goto:
aol://5863:126/rec.crafts.metalworking or go thru Google.com
to reach it if you have trouble.


I consider
this to be a sister site to the CCED group, as many of the
same members are there, for OT subjects, that are not allowed
on the CCED list.

NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY
POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO
EXCEPTIONS........
bill
List Mom
List Owner


Yahoo! Groups Links
Re: nice servos from plotter

 

Hi Rick,
I'm thinking about laser engraving plastic labels and possibly
lasercutting steel at a later stage as i'm currently paying for
both
these services.
Can you tell me what types of laser I would need and where I could
buy
them at a reasonable price? I'm in Australia.
Thanks,
Glen.
That is such a huge difference in applications. Engraving plastic
labels is a 10 to 20 watt job, Cutting steel is a 200+ watt job.

10 to 20 watt lasers can be found new for under $3000 US. 200+ watt
lasers are going to be around $20000 to $30000 US.

Ebay can be a decent place for laser deals if you know what you are
doing. It is also quite easy to buy a rather heavy paperweight on
ebay.
Re: water jet cam

Les Newell
 

SheetCam <www.sheetcam.com> can do this at a much lower price. I can write a post processor for you that will slow down to a preset percentage of the normal feed rate on arcs. The post could even be configured to slow down more for tighter arcs.

Les

afogassa wrote:

Hi Peter,
I do have deskcnc and it's good enough for this, but water jets needs a good cam that can look way ahead and predicts what is going to happen and than starts to adjust the feed rate before it gets to a corner or radius to compensate for Jet lag doing that manualy would be a pain if not impossible.
Got a quote from PEPs and it runs at 10K US$ (ouch !!)
I've being thinking about getting a working G code, than work this out on excel to adjust the feed rate.
Re: nice servos from plotter

roboticscnc
 

--- In CAD_CAM_EDM_DRO@..., "skykotech" <rick@...> wrote:

Hi guys,

Haven't posted in awhile...been busy this summer with other
projects. I just disassembled a HP7550A pen plotter and cut down
the carriage to make a lightweight Y axis for a laser engraver. The
plotter was all of $15 purchased locally, and includes two very nice
pittman servos with encoders. They are pretty small, but actually
have quite a bit of power. Of course there are little forces with a
flying lens laser engraver, but perhaps they could be used to move a
camera for a 3D digitizer or something similar. I am driving them
with a Pixie P100 step/dir to analog converter (www.skyko.com)
hooked to an Advanced Motion Controls 12A8 brush amplifier (a bit
overkill).

Here is a quick video of the carriage moving at 2640IPM running on
Mach3. The carriage actually takes 4000 steps to move 1 inch, but I
have set the step multiply in the Pixie P100 to 4x. With Mach3
outputting a max of around 45khz, this gives me 1000dpi resolution
and the 2640IPM travel speed (fairly fast, no?)



-Rick
Hi Rick,
I'm thinking about laser engraving plastic labels and possibly
lasercutting steel at a later stage as i'm currently paying for both
these services.
Can you tell me what types of laser I would need and where I could buy
them at a reasonable price? I'm in Australia.
Thanks,
Glen.
Re: Open (i think) design for a parallel robot (reprap may be interested)

 

"Dennis Schmitz":
Speaking of which. I think the reprap machine could make strong structural
elements out of that plastic if they laminated it with some glass fabric.
With a 90deg rotary table they could make fiberglass tubing.
Hmm... That is a thought, like the new carbon fiber fuselage barrels on the
Boeing_787, (or conventional fiber tubing, I just think the new planes are
cool).




It seems very complicated, but worth considering after getting the thing to
work.

"Ron Yost":
On Friday 01 September 2006 00:28, Ron Yost wrote:
Is it just me, or are there others wondering what these machines are
intended for?

How can the apparent goal of self-replication (of a largely metalic
machine) be
accomplished by squirting layers of hot-melt plastics? Or carving foam??
If you look at the pictures of the extrusion head and Ed's ARNIE.


I admit, there's an awful lot of metal there. We'll eventually eliminate more
and more of it, but we'll never get rid of that little brass nozzle at the
end, because that's going to be at or above the melting point for the
plastic.

Right now, the point isn't to make a perfect Von Neuman machine. It's to make
a practical one. And that means it's ok to include off-the-shelf items like
stepper motors or drill rod.

That's plastic's really damn tough stuff, by the way. I wouldn't feel
uncomfortable using a tool box made out of it.

They're fascinating to watch .. but other than rapid-prototyping (making
plastic
models of things), and/or as a conceptual challenge, of what utility are
they for getting -real work- done??? Or is that not the point?? Is it all
really academic for you folks? Engineering student toys, in other words.
That's how it sounds to me, so far. Maybe it's enough to get it built and
moving, with little thought as to what can actually be -done- with the
thing?? A useless robot, in other words. But utility may not be the
point. In which case, why is the whole thing relevant here?
The point is not making models. The point is making anything you've got
laying about that's made out of plastic. Like your laser printer needs a new
plastic gear, or you need some new drippers for your irrigation line. Or a
bunch of sewing machine parts.

You can use it to make other tools, too. Like a wire EDM machine,
hypothetically. We've shelved the "Slap a wire EDM head on the RepRap" idea
for now. But, for example, Graham's going to put his work up online, and I
will hope we'll be able to make most of the parts of plastic.

Things have to be really beefy to do heavy, yet precise, work in steel,
and I don't see how eliminating mass is going to work at all for us home-
shop types doing metal. Plastic bearings wouldn't last long at all,
either.
We aren't planning on using the RepRap to do subtractive fabrication work in
steel. It's not for throwing chips. It's for additive fabrication.

Here I think your note starts to segue into a discussion of the general merits
of hexapods for conventional machining. I'll leave that to the experts. I
don't know if you can use the stiffness of the tripod/hexapod to make up for
the lower mass, or what the mechanics are there..

There is one thing to keep in mind. We're hoping to have a slurry deposition
head working soonish. That will be able to deposit titanium nitride, other
ceramics, aluminum powder. We'll do it layer by layer, or slip-cast into a
plastic mold, but pop that in a furnace/kiln to sinter the particles, and
you've got a hard finished piece. Which should impress the folk who aren't
impressed with plastic. (

Yes, I know a tripod is a very strong structure. And I do get the concept
of the things. But, there has to be mass somewhere, doesn't there?? How
can a decent spindle holding real milling cutters hang off spindly legs??
Or is there a 'scale' thing here I'm not getting?

I DO admire those who think out-of-the-box, tho. And I sure hope you
smart folks can come up with a revolutionary home-built, -useful- for
everyday work, machine.

Ron Yost .. looks at his quaint mill and lathe and ponders the universe.
Right now, we're looking at making a machine that will make whatever you want
out of plastic, given the constraints that it's going to be made from .5 mm
filaments and will have to fit in an initial working volume of about 30 cm on
a side. But the project lead used his conventional RP to make a peristaltic
pump for the slurry head, along with a slurry-filed-syringe-squeezing device,
and if every group member had a working RP, we'd be a lot further ahead.

I wish I had a bigger mill and a bigger lathe, and I think there will always
be a place for them. (I only hope I'll be able to convice my wife of that.)
But for stuff on the 30cm scale, we're going to find rapid prototypers really
useful. And kids will discover the things, and start working with their
hands again, which should be interesting.

Regards,
Sebastien Bailard
10821 - 10840 of 99862