Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Thursday 04 June 2020 19:49:36 Chris Albertson wrote:

> That is such a good idea!
>
> It eliminates all the overhang.  I took this idea and combined it with
> what I do and made a hybrid.   One half of this in made on a lathe out
> of steel or aluminum and the other half is printed.The "hybrd"
> pulley would last for years.
>
> This turns an intermediate skill level print job into two
> beginner-level jobs one on a lathe and one on the printer.   Join the
> two with epoxy or CA glue.   Some of this group could do this lathe
> work before the printer is half done.
>
> Here is a 3D view of this https://a360.co/3eUpZE6
> 
>
> Just in case the above link fails here is a render in 2D.   I might
> actually do this.  Of course, this applies to things like helical
> gears and so on.
>
>
> [image: HybridPulley.jpeg]
>
Neat as can be.  Lemme see what I can cobble up out of the parametric 
sprocket kit. I think I've some 1.75" dia alu to make the hubs from.

Looking at this one, 80% done, it looks like the teeth are twisted at a 
high angle, like 75 or more degrees?  Crazy... 
>
>
> On Thu, Jun 4, 2020 at 3:48 PM Gregg Eshelman via Emc-users <
>
> emc-users@lists.sourceforge.net> wrote:
> > For a toothed pulley with a flange on both sides I'd modify the 3D
> > model to make one flange a separate part, with features on it and
> > the body of the pulley to align it so that when glued on it will be
> > concentric.
> >
> > To glue PLA, cyanoacrylate (super glue) works well. So does
> > tetrahydrofuran, which is in some types of PVC pipe cleaner/primer.
> > The PVC cleaners without THF won't bond PLA.
> > The ridged surfaces of FDM prints can be used to make parts that fit
> > together like they're snap fit. Sizing part fits just right then
> > adjusting extrusion can make the same models easily drop together, a
> > light press fit that holds but is separable, or a press fit that's
> > not tight enough to distort but is never coming apart without
> > something breaking.
> >
> > On Thursday, June 4, 2020, 3:14:31 PM MDT, Chris Albertson <
> > albertson.ch...@gmail.com> wrote:
> >  If you have not enabled supports and are printing an object like a
> > pulley you WILL have a total mess.3D printer need a surface and
> > an part of the part that overhangs with just air onder it will not
> > print well as the hot plastic will just fall out the nozzle.
> >
> > But that cross hatch pattern looks like support base so it must be
> > enabled. You can enable support either "from the baseplate up" or
> > "everywhere" and you need "everywhere" as at to support the top
> > flange.
> >
> > Yes, removing support is a PIA because on a pulley the teeth will be
> > completely 100% inside a ring of support material.
> >
> > For a beginner you picked a hard project.  Most people would start
> > by printing a one-inch cube or a 1/2 inch flat washer.  Pulleys have
> > need of support and have printed threads for the set screw.  Both as
> > "intermediate level" skills.Horizontal threads always have
> > support inside that needs pin punch (hex key) to remove
> >
> > I had to modify the pulley design so it could print with minimal
> > support. Take all the ridges off the outside, make the flange
> > thicker and radius the inside of the flange
> >
> > It is also possible to control the support density and pattern.
> >
> > Getting all this right nly tak seconds if you know to do it.  I
> > start in Fusion and vew thepart from al sides to see if it can be
> > better designed to reduce the need for support.  Then in Cura I try
> > a few suport techniques and use preview to see where it is going to
> > go.  If it looks bad, then back to Fusion to change an angle or
> > whatever.This is why engineers like really fast workstatins as
> > design is iterative.
> >
> > I'll look at a file if you can e-mail it.
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Thursday 04 June 2020 19:34:03 Gregg Eshelman via Emc-users wrote:

> What format is the original model? To convert to STL the model has to
> be solid or "water tight". No missing faces and all one piece. A bunch
> of solid parts 'glued together' can cause problems like what you're
> experiencing, especially if the parts intersect. Other issues that can
> crop up with 3D CAD files are disconnected vertexes and edges that
> look like they're connected. Doubled lines, vertexes, and faces.
> Backwards normals (what's supposed to be the outside of a face
> specified as the inside) and various other screwed up stuff. I dread
> having to work with stuff people have designed in Sketchup. The
> software may as well be called screwup because of how easily people
> can create bad geometry with it.
>
> Try this parametric pulley customizer to get a model that should be 3D
> printing sympatico. https://www.thingiverse.com/thing:16627

Thats what I am using Gregg.  I think from a previous post of yours.
Thanks.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Fwd: missing feature of openscad

[Gregg Eshelman via Emc-users]

What format is the original model? To convert to STL the model has to be solid 
or "water tight". No missing faces and all one piece. A bunch of solid parts 
'glued together' can cause problems like what you're experiencing, especially 
if the parts intersect. Other issues that can crop up with 3D CAD files are 
disconnected vertexes and edges that look like they're connected. Doubled 
lines, vertexes, and faces. Backwards normals (what's supposed to be the 
outside of a face specified as the inside) and various other screwed up stuff. 
I dread having to work with stuff people have designed in Sketchup. The 
software may as well be called screwup because of how easily people can create 
bad geometry with it.

Try this parametric pulley customizer to get a model that should be 3D printing 
sympatico. https://www.thingiverse.com/thing:16627

On Thursday, June 4, 2020, 10:24:43 AM MDT, Gene Heskett 
 wrote:  
 
 On Thursday 04 June 2020 08:13:53 andy pugh wrote:

> On Thu, 4 Jun 2020 at 12:20, Gene Heskett 
> wrote:
>
> Preview has a camera view angle that takes the image off the bottom of
>
> > the screen, long before the magnification has reached a usefull
> > level.
>
> Shift-drag, Ctrl-drag and Alt-Drag all do different things to the
> preview.

Crazy. But the build in progress is totally screwed, theres a post of 50% 
infill where the shaft hole s/b, and the wall around the shaft is 
missing! Taking the raft off took most of the infill with it because 
there was no solid bottom or top to a 12mm tall hub that measures 12.5mm 
tall now.  The only conclusion I can reach is that I've done something 
to the src file, which I've been doing a save-as to the modified code 
before handing it off to the slicer each time.  So go back to the 
original src and start all over.

Which I did, but stopped that build when it was obvious it was going to 
do the same miss-build again.

1. no bottom hub wall
2. no wall around shaft or nut pocket
3. nut pocket 100% infilled
4. middle of whats supposed to be an 8mm shaft infilled
5. Scan attached for the experts perusal, whats fubared in cura?

 But I think I'll go get the tooth count I need to put the 2nd motor on 
the Sheldon's Z, and see if I can find an alu sprocket for that.

Cheers, Gene Heskett  
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Re: [Emc-users] Fwd: missing feature of openscad

[Gregg Eshelman via Emc-users]

For a toothed pulley with a flange on both sides I'd modify the 3D model to 
make one flange a separate part, with features on it and the body of the pulley 
to align it so that when glued on it will be concentric. 

To glue PLA, cyanoacrylate (super glue) works well. So does tetrahydrofuran, 
which is in some types of PVC pipe cleaner/primer. The PVC cleaners without THF 
won't bond PLA.
The ridged surfaces of FDM prints can be used to make parts that fit together 
like they're snap fit. Sizing part fits just right then adjusting extrusion can 
make the same models easily drop together, a light press fit that holds but is 
separable, or a press fit that's not tight enough to distort but is never 
coming apart without something breaking.

On Thursday, June 4, 2020, 3:14:31 PM MDT, Chris Albertson 
 wrote:  
 If you have not enabled supports and are printing an object like a pulley
you WILL have a total mess.    3D printer need a surface and an part of the
part that overhangs with just air onder it will not print well as the hot
plastic will just fall out the nozzle.

But that cross hatch pattern looks like support base so it must be enabled.
    You can enable support either "from the baseplate up" or "everywhere"
and you need "everywhere" as at to support the top flange.

Yes, removing support is a PIA because on a pulley the teeth will be
completely 100% inside a ring of support material.

For a beginner you picked a hard project.  Most people would start by
printing a one-inch cube or a 1/2 inch flat washer.  Pulleys have need of
support and have printed threads for the set screw.  Both as
"intermediate level" skills.    Horizontal threads always have
support inside that needs pin punch (hex key) to remove

I had to modify the pulley design so it could print with minimal support.
Take all the ridges off the outside, make the flange thicker and radius the
inside of the flange

It is also possible to control the support density and pattern.

Getting all this right nly tak seconds if you know to do it.  I start in
Fusion and vew thepart from al sides to see if it can be better designed to
reduce the need for support.  Then in Cura I try a few suport techniques
and use preview to see where it is going to go.  If it looks bad, then
back to Fusion to change an angle or whatever.    This is why engineers
like really fast workstatins as design is iterative.

I'll look at a file if you can e-mail it.  
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Re: [Emc-users] Fwd: missing feature of openscad

[Chris Albertson]

It sounds like you checked the "print a mold" box.  Cura can do this.  The
part is then made of air surrounded by plastic.   (People do this so they
can fill the void space with resin or maybe wax to make a candle.   It is a
REALLY good way to make a shoft rubber over-molded part.Let's say you
made a hammer handle in steel on a lathe. Place it inside a printed mold
and pour in the rubber and get finger grips over a steel shaft.   It's
useful but not now.)

If you didn't evidently click "mold" then there is something wrong with the
STL file.  The file SHOULD specify which side is the inside and which is
the outside.   This can be messed up.   Without knowing the history of the
STL file, I can't say.Send the files, The STL, and the *.3mf files you
get when you do File->Save in Cura. (.3mf has all your settings)

Are you making the file in openscad?  f so it is easy to make an
unprintable model.  It is a topological thing where what you actually made
is the inside of a pulley.  I guessing blind here.



-- 

Chris Albertson
Redondo Beach, California

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Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Thursday 04 June 2020 17:11:49 Chris Albertson wrote:

> If you have not enabled supports and are printing an object like a
> pulley you WILL have a total mess.3D printer need a surface and an
> part of the part that overhangs with just air onder it will not print
> well as the hot plastic will just fall out the nozzle.
>
> But that cross hatch pattern looks like support base so it must be
> enabled. You can enable support either "from the baseplate up" or
> "everywhere" and you need "everywhere" as at to support the top
> flange.
>
> Yes, removing support is a PIA because on a pulley the teeth will be
> completely 100% inside a ring of support material.
>
> For a beginner you picked a hard project.   Most people would start by
> printing a one-inch cube or a 1/2 inch flat washer.   Pulleys have
> need of support and have printed threads for the set screw.  Both as
> "intermediate level" skills.Horizontal threads always have
> support inside that needs pin punch (hex key) to remove
>
> I had to modify the pulley design so it could print with minimal
> support. Take all the ridges off the outside, make the flange thicker
> and radius the inside of the flange
>
> It is also possible to control the support density and pattern.
>
> Getting all this right nly tak seconds if you know to do it.  I start
> in Fusion and vew thepart from al sides to see if it can be better
> designed to reduce the need for support.   Then in Cura I try a few
> suport techniques and use preview to see where it is going to go.   If
> it looks bad, then back to Fusion to change an angle or whatever.
> This is why engineers like really fast workstatins as design is
> iterative.
>
> I'll look at a file if you can e-mail it.
>
Which file, the gcode that was copied to the printer? or ??


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Fwd: missing feature of openscad

[Chris Albertson]

If you have not enabled supports and are printing an object like a pulley
you WILL have a total mess.3D printer need a surface and an part of the
part that overhangs with just air onder it will not print well as the hot
plastic will just fall out the nozzle.

But that cross hatch pattern looks like support base so it must be enabled.
You can enable support either "from the baseplate up" or "everywhere"
and you need "everywhere" as at to support the top flange.

Yes, removing support is a PIA because on a pulley the teeth will be
completely 100% inside a ring of support material.

For a beginner you picked a hard project.   Most people would start by
printing a one-inch cube or a 1/2 inch flat washer.   Pulleys have need of
support and have printed threads for the set screw.  Both as
"intermediate level" skills.Horizontal threads always have
support inside that needs pin punch (hex key) to remove

I had to modify the pulley design so it could print with minimal support.
Take all the ridges off the outside, make the flange thicker and radius the
inside of the flange

It is also possible to control the support density and pattern.

Getting all this right nly tak seconds if you know to do it.  I start in
Fusion and vew thepart from al sides to see if it can be better designed to
reduce the need for support.   Then in Cura I try a few suport techniques
and use preview to see where it is going to go.   If it looks bad, then
back to Fusion to change an angle or whatever. This is why engineers
like really fast workstatins as design is iterative.

I'll look at a file if you can e-mail it.



On Thu, Jun 4, 2020 at 1:36 PM Gene Heskett  wrote:

> On Thursday 04 June 2020 13:09:10 Chris Albertson wrote:
>
> > Can you save
>
> > 1) the STL file
> yes, I have that, created by openscad
> > 2) the gcode file
> yes, I have that, the .stl file as  sliced by cura
> > 3) Then in Cura to File-> and it will save the project file
> Where is this menu? The only write capability I can find in cura is a
> save gcode to file, only after the .stl has been sliced.
>
> > which has
> > all the settings including how you positioned the model on the build
> > plate.
> >
> > I'd look at these fies.
> >
> > But my guess is this is a data error.  The gcode file is
> > gettig corrupted or read wrong by the printer.   This is rare if using
> > an SD card but if you are feeding the printer via the USB that it is
> > understandable.  It looks like data is being dropped, missing g-codes
> > make a mess of the print.
>
> I've pulled up a chair and a cuppa, watching how it makes the 2nd pass at
> a 30 tooth pulley, XL belt style, with one 5mm grub screw and an 8mm
> shaft hole in a 24mm hub OD.
>
> 7mm into the build, its looking like its extending support at about a 50%
> fill (its turned off) coming out of the base of the hub at a 45 degree
> angle outward. Starting at the base.
>
> The grub screw location, and its nut is a 100% fill, the reverse of what
> I could see in openscad or cura, and is extended to a point about 1mm
> past the center of the hub.
>
> Supposed to have an 8mm shaft hole, surrounded by 5mm walls, the central
> hole is 24 or 25mm in diameter, full of air.  Except for the post of
> plastic where the grub screw and its nut belongs. I just took a look at
> that, but I expect to see the peak of the hex nut laid up in plastic,
> but at 8.39mm off the bed, it hasn't gotten there yet.
>
> This may be my mistake, it looks good even in cura, including the 8mm
> shaft hole.
>
> TBH the last time I saw this many bugs I was standing over a 10 day old
> road killed deer in mid-August.  The only thing missing is the odor.
>
> I'm going to let it finish just to see where else it fscks up, but thats
> the first 24% and 8.39mm off the hot plate.  Haven't gotten anywhere
> near the sprocket yet.  FWIW, the calibrate with paper sucks, I have it
> gently touching the plate, which isn't that flat, and adhesion is good,
> but dragging a sheet of 22lb thru it is hairball high, no stick at all.
>
> I suspect its doing exactly what the gcode is telling it to.  Is there a
> place to send pix to the cura people to look at and tell me I'm an
> ID10T?
>
> >
> > One more thing,  It could be that Cura is generating supports inside
> > the screw holes. It might not be infill but rather a support
> >
> > Is the pulley dead-flat?  and you are printing it hub extension up.
> > If the model is not in full contact with the plate because perhaps
> > there is a ridge or bump that holds some surface off the plat that
> > this cross hatching is the base of some support materials.   Cura uses
> > a cross hatch as the first layer of support material.
> >
> > If is best if the base of everything you print is a flat plane.   I
> > can't tell without a look at the files.
> >
> > One more thing, for objects like this try "Gyroid" infill type.  It
> > makes a 3D patterns like open-cell foam using intersecting sine waves.
> >  About 25% is enough for this 

Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Thursday 04 June 2020 13:09:10 Chris Albertson wrote:

> Can you save

> 1) the STL file
yes, I have that, created by openscad
> 2) the gcode file
yes, I have that, the .stl file as  sliced by cura
> 3) Then in Cura to File-> and it will save the project file
Where is this menu? The only write capability I can find in cura is a 
save gcode to file, only after the .stl has been sliced.

> which has 
> all the settings including how you positioned the model on the build
> plate.
>
> I'd look at these fies.
>
> But my guess is this is a data error.  The gcode file is
> gettig corrupted or read wrong by the printer.   This is rare if using
> an SD card but if you are feeding the printer via the USB that it is
> understandable.  It looks like data is being dropped, missing g-codes
> make a mess of the print.

I've pulled up a chair and a cuppa, watching how it makes the 2nd pass at 
a 30 tooth pulley, XL belt style, with one 5mm grub screw and an 8mm 
shaft hole in a 24mm hub OD.

7mm into the build, its looking like its extending support at about a 50% 
fill (its turned off) coming out of the base of the hub at a 45 degree 
angle outward. Starting at the base.

The grub screw location, and its nut is a 100% fill, the reverse of what 
I could see in openscad or cura, and is extended to a point about 1mm 
past the center of the hub.

Supposed to have an 8mm shaft hole, surrounded by 5mm walls, the central 
hole is 24 or 25mm in diameter, full of air.  Except for the post of 
plastic where the grub screw and its nut belongs. I just took a look at 
that, but I expect to see the peak of the hex nut laid up in plastic, 
but at 8.39mm off the bed, it hasn't gotten there yet.

This may be my mistake, it looks good even in cura, including the 8mm 
shaft hole.

TBH the last time I saw this many bugs I was standing over a 10 day old 
road killed deer in mid-August.  The only thing missing is the odor.

I'm going to let it finish just to see where else it fscks up, but thats 
the first 24% and 8.39mm off the hot plate.  Haven't gotten anywhere 
near the sprocket yet.  FWIW, the calibrate with paper sucks, I have it 
gently touching the plate, which isn't that flat, and adhesion is good, 
but dragging a sheet of 22lb thru it is hairball high, no stick at all.

I suspect its doing exactly what the gcode is telling it to.  Is there a 
place to send pix to the cura people to look at and tell me I'm an 
ID10T?

>
> One more thing,  It could be that Cura is generating supports inside
> the screw holes. It might not be infill but rather a support
>
> Is the pulley dead-flat?  and you are printing it hub extension up.   
> If the model is not in full contact with the plate because perhaps
> there is a ridge or bump that holds some surface off the plat that
> this cross hatching is the base of some support materials.   Cura uses
> a cross hatch as the first layer of support material.
>
> If is best if the base of everything you print is a flat plane.   I
> can't tell without a look at the files.
>
> One more thing, for objects like this try "Gyroid" infill type.  It
> makes a 3D patterns like open-cell foam using intersecting sine waves.
>  About 25% is enough for this part.
>
> My guess is "data error" is this is done via USB or if there is a
> ridge on the pulley it might be suport but suort is printed in X and Y
> direction not at 45 degrees.  But I don't know the camera angle.
>
> On Thu, Jun 4, 2020 at 9:24 AM Gene Heskett  
wrote:
> > On Thursday 04 June 2020 08:13:53 andy pugh wrote:
> > > On Thu, 4 Jun 2020 at 12:20, Gene Heskett 
> > > wrote:
> > >
> > > Preview has a camera view angle that takes the image off the
> > > bottom of
> > >
> > > > the screen, long before the magnification has reached a usefull
> > > > level.
> > >
> > > Shift-drag, Ctrl-drag and Alt-Drag all do different things to the
> > > preview.
> >
> > Crazy. But the build in progress is totally screwed, theres a post
> > of 50% infill where the shaft hole s/b, and the wall around the
> > shaft is missing! Taking the raft off took most of the infill with
> > it because there was no solid bottom or top to a 12mm tall hub that
> > measures 12.5mm tall now.  The only conclusion I can reach is that
> > I've done something to the src file, which I've been doing a save-as
> > to the modified code before handing it off to the slicer each time. 
> > So go back to the original src and start all over.
> >
> > Which I did, but stopped that build when it was obvious it was going
> > to do the same miss-build again.
> >
> > 1. no bottom hub wall
> > 2. no wall around shaft or nut pocket
> > 3. nut pocket 100% infilled
> > 4. middle of whats supposed to be an 8mm shaft infilled
> > 5. Scan attached for the experts perusal, whats fubared in cura?
> >
> >  But I think I'll go get the tooth count I need to put the 2nd motor
> > on the Sheldon's Z, and see if I can find an alu sprocket for that.
> >
> > Cheers, Gene Heskett
> > --
> > "There are four boxes to be used 

Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Thursday 04 June 2020 13:09:10 Chris Albertson wrote:

> Can you save
> 1) the STL file
> 2) the gcode file
> 3) Then in Cura to File-> and it will save the project file  which has
> all the settings including how you positioned the model on the build
> plate.
>
> I'd look at these fies.

Do you want to see them?
>
> But my guess is this is a data error.  The gcode file is
> gettig corrupted or read wrong by the printer.   This is rare if using
> an SD card but if you are feeding the printer via the USB that it is
> understandable.  It looks like data is being dropped, missing g-codes
> make a mess of the print.
>
>
> One more thing,  It could be that Cura is generating supports inside
> the screw holes. It might not be infill but rather a support
>
No supports enabled that I know of.
> Is the pulley dead-flat?  and you are printing it hub extension up.

No, what you saw was hub face down, so after the raft, should have been 
the bottom, 4mm thick layer, and its not being laid down at all. Twice 
in a row.
> 
> If the model is not in full contact with the plate because perhaps
> there is a ridge or bump that holds some surface off the plat that
> this cross hatching is the base of some support materials.   Cura uses
> a cross hatch as the first layer of support material.
>
yes, thats what you are looking at, I just put it, top side down, raft 
and all, in the scanner.

> If is best if the base of everything you print is a flat plane.   I
> can't tell without a look at the files.
>
> One more thing, for objects like this try "Gyroid" infill type.  It
> makes a 3D patterns like open-cell foam using intersecting sine waves.
>  About 25% is enough for this part.

that is whats selected.
>
> My guess is "data error" is this is done via USB or if there is a
> ridge on the pulley it might be suport but suort is printed in X and Y
> direction not at 45 degrees.  But I don't know the camera angle.
>
> On Thu, Jun 4, 2020 at 9:24 AM Gene Heskett  
wrote:
> > On Thursday 04 June 2020 08:13:53 andy pugh wrote:
> > > On Thu, 4 Jun 2020 at 12:20, Gene Heskett 
> > > wrote:
> > >
> > > Preview has a camera view angle that takes the image off the
> > > bottom of
> > >
> > > > the screen, long before the magnification has reached a usefull
> > > > level.
> > >
> > > Shift-drag, Ctrl-drag and Alt-Drag all do different things to the
> > > preview.
> >
> > Crazy. But the build in progress is totally screwed, theres a post
> > of 50% infill where the shaft hole s/b, and the wall around the
> > shaft is missing! Taking the raft off took most of the infill with
> > it because there was no solid bottom or top to a 12mm tall hub that
> > measures 12.5mm tall now.  The only conclusion I can reach is that
> > I've done something to the src file, which I've been doing a save-as
> > to the modified code before handing it off to the slicer each time. 
> > So go back to the original src and start all over.
> >
> > Which I did, but stopped that build when it was obvious it was going
> > to do the same miss-build again.
> >
> > 1. no bottom hub wall
> > 2. no wall around shaft or nut pocket
> > 3. nut pocket 100% infilled
> > 4. middle of whats supposed to be an 8mm shaft infilled
> > 5. Scan attached for the experts perusal, whats fubared in cura?
> >
Being sliced, saved as gcode to the local nc_files, then chowned to root 
and then cp'd to the 8G sd card that came with the printer, after 
mounting it as a vfat partition.

> >  But I think I'll go get the tooth count I need to put the 2nd motor
> > on the Sheldon's Z, and see if I can find an alu sprocket for that.

Ordered, s/b here in a couple weeks.

Thanks Chris.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Fwd: missing feature of openscad

[Chris Albertson]

Can you save
1) the STL file
2) the gcode file
3) Then in Cura to File-> and it will save the project file  which has all
the settings including how you positioned the model on the build plate.

I'd look at these fies.

But my guess is this is a data error.  The gcode file is
gettig corrupted or read wrong by the printer.   This is rare if using an
SD card but if you are feeding the printer via the USB that it is
understandable.  It looks like data is being dropped, missing g-codes make
a mess of the print.


One more thing,  It could be that Cura is generating supports inside the
screw holes. It might not be infill but rather a support

Is the pulley dead-flat?  and you are printing it hub extension up.If
the model is not in full contact with the plate because perhaps there is a
ridge or bump that holds some surface off the plat that this cross hatching
is the base of some support materials.   Cura uses a cross hatch as the
first layer of support material.

If is best if the base of everything you print is a flat plane.   I can't
tell without a look at the files.

One more thing, for objects like this try "Gyroid" infill type.  It makes a
3D patterns like open-cell foam using intersecting sine waves.  About 25%
is enough for this part.

My guess is "data error" is this is done via USB or if there is a ridge on
the pulley it might be suport but suort is printed in X and Y direction not
at 45 degrees.  But I don't know the camera angle.

On Thu, Jun 4, 2020 at 9:24 AM Gene Heskett  wrote:

> On Thursday 04 June 2020 08:13:53 andy pugh wrote:
>
> > On Thu, 4 Jun 2020 at 12:20, Gene Heskett 
> > wrote:
> >
> > Preview has a camera view angle that takes the image off the bottom of
> >
> > > the screen, long before the magnification has reached a usefull
> > > level.
> >
> > Shift-drag, Ctrl-drag and Alt-Drag all do different things to the
> > preview.
>
> Crazy. But the build in progress is totally screwed, theres a post of 50%
> infill where the shaft hole s/b, and the wall around the shaft is
> missing! Taking the raft off took most of the infill with it because
> there was no solid bottom or top to a 12mm tall hub that measures 12.5mm
> tall now.  The only conclusion I can reach is that I've done something
> to the src file, which I've been doing a save-as to the modified code
> before handing it off to the slicer each time.  So go back to the
> original src and start all over.
>
> Which I did, but stopped that build when it was obvious it was going to
> do the same miss-build again.
>
> 1. no bottom hub wall
> 2. no wall around shaft or nut pocket
> 3. nut pocket 100% infilled
> 4. middle of whats supposed to be an 8mm shaft infilled
> 5. Scan attached for the experts perusal, whats fubared in cura?
>
>  But I think I'll go get the tooth count I need to put the 2nd motor on
> the Sheldon's Z, and see if I can find an alu sprocket for that.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>


-- 

Chris Albertson
Redondo Beach, California

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Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Thursday 04 June 2020 08:13:53 andy pugh wrote:

> On Thu, 4 Jun 2020 at 12:20, Gene Heskett 
> wrote:
>
> Preview has a camera view angle that takes the image off the bottom of
>
> > the screen, long before the magnification has reached a usefull
> > level.
>
> Shift-drag, Ctrl-drag and Alt-Drag all do different things to the
> preview.

Crazy. But the build in progress is totally screwed, theres a post of 50% 
infill where the shaft hole s/b, and the wall around the shaft is 
missing! Taking the raft off took most of the infill with it because 
there was no solid bottom or top to a 12mm tall hub that measures 12.5mm 
tall now.  The only conclusion I can reach is that I've done something 
to the src file, which I've been doing a save-as to the modified code 
before handing it off to the slicer each time.  So go back to the 
original src and start all over.

Which I did, but stopped that build when it was obvious it was going to 
do the same miss-build again.

1. no bottom hub wall
2. no wall around shaft or nut pocket
3. nut pocket 100% infilled
4. middle of whats supposed to be an 8mm shaft infilled
5. Scan attached for the experts perusal, whats fubared in cura?

 But I think I'll go get the tooth count I need to put the 2nd motor on 
the Sheldon's Z, and see if I can find an alu sprocket for that.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 
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Re: [Emc-users] Fwd: missing feature of openscad

[andy pugh]

On Thu, 4 Jun 2020 at 12:20, Gene Heskett  wrote:

Preview has a camera view angle that takes the image off the bottom of
> the screen, long before the magnification has reached a usefull level.


Shift-drag, Ctrl-drag and Alt-Drag all do different things to the preview.

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is designed
for the especial use of mechanical geniuses, daredevils and lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1912

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Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Wednesday 03 June 2020 23:05:12 Chris Albertson wrote:

> On Wed, Jun 3, 2020 at 7:33 PM Gene Heskett  
wrote:
> > On Wednesday 03 June 2020 19:17:14 Chris Albertson wrote:
> > > You are going to have to post a photo.  First off, I hope you are
> > > printing these pulleys flat,  With rotational axis vertical.  I
> > > hate to ask but with no photos we don't even know this.
> > >
> > > Assuming you are, the teeth are called "walls" and only if bubbles
> > > are in the plastic would you get voids.Print slower or maybe
> > > cooler. The outer wall layers should run at maybe 30 mm / second.
> > >
> > > Here is a cell-phone shot of a 30T GT2 profile pulley that has
> > > been sitting around on my desk for a couple weeks.  It is dirty
> > > and the flanges need to be cleaned up with a small nail file.
> > > The walls are made in the direction of motion and are smooth
> > > enough.  It is a 3mm tooth pitch by 9mm wide.I think this one
> > > was printed on "draft mode" with 0.2mm layer height.   This is
> > > from an Anet A6 printer with default settings in Cura. A steel hub
> > > goes in the 20mm hole.  THe gear was downloaded from SPD/SI
> > > website than modified in Fusion 360
> > >
> > > [image: IMG_0542.jpg]
> >
> > Thats a heck of a lot nicer looking, and 10x smoother than what I
> > have in my hand from this afternoons run.  That said, an XL belt
> > fits it nicely. So this one is usable for a test fit mock up except
> > the slot for the nut is about a 20% infill.  One might be able to
> > epoxy it to the motor shaft with JBWeld. But despite 2mm walls
> > around the hub, I can feel the elasticity and that bothers me.  And
> > while I can sort of see the solid walls around the nut pocket, I
> > have serious doubts of ever getting a decent grip because it will
> > open up from the outward pressure the nut would exert.
>
> Yes, That is why I make pulleys with a 20 or 24 mm hole.  They get
> epoxied to a steel hub.   Steel hubs are easy to make on a lathe by
> hand.  I use two set scres at 90 degrees.  I could epoxy to the motor
> shaft but then I might want to use the motor later with a different
> pulley.
>
> One thing that does work for a while,  If the motor has a "D" shaft or
> a keyway you can print a D or keyway in the pulley.  D-holes don't
> spin but the loose concentric over time.
>
> There is one more technique I want to try.  Brass thread inserts.  You
> heat these on a solder iron tht press them into a hole. When the
> plastic cools they stick
> amazon.com/Uxcell-a16041800ux0824-Knurled-Thread
> ent/dp/B01IYWTCWW/ref=pd_sbs_60_2/140-9661733-2175833?_encoding=UTF8
>_rd_i=B01IYWTCWW_rd_r=adfaa131-87de-4bc3-9678-232764f895cb_rd_w=U
>5P0Q_rd_wg=rKlV4_rd_p=d9804894-61b7-40b3-ba58-197116cffd9d_rd_
>r=X28MD5MCYFYFCWH10C9X=1=X28MD5MCYFYFCWH10C9X>
>
> If you have access to the backside you can press-fit normal hex nuts
> and embed them into the plastic but these knured nuts press in from
> the front side and might work for gears.   That would be quicker them
> making a steel hub.  Kind of a compromise.   6 cents each.
>
> Finally if you print threads, the wall and skin thrickness setting
> applies to the  plastic around all holes, threaded of not
>
> Use "preview" in Cura to see exactly how each layer will stack up

Preview has a camera view angle that takes the image off the bottom of 
the screen, long before the magnification has reached a usefull level.
Changing its view style does not allow the image to remain on screen in 
either mode.  Its aimed at a point about 160mm above the bed. It needs 
to scroll vertically and doesn't. xray view is blank. But I finally got 
that, but still can't blow it up enough to see. So I increased the wall 
thickness, and reduced the nut height half a mill and fired off another 
make. Sped it up to 100mm too.

> > So I'll probably use this as the motor pulley while I am mocking up
> > the real drive, the next stage being a hubless, larger model, which
> > will be epoxied to a smallish possibly herringboned gear, driving a
> > much higher tooth count matching gear on the worm shaft. The
> > herringbone may get lost in the translation to metal for the final
> > parts though.
> >
> > I set up a "raft" for this one, and made it 15mm bigger than the
> > hub, and it was 30 minutes just laying the raft. 4 layers.  Bed
> > cold, I wiggled the putty knife under it, popped it off, then the
> > raft separated nicely just like cura said it would. I upped the
> > speed to 60mm/sec but I don't think it ever moved that fast. But I
> > think a 5mm skirt would be ok and 20 minutes faster.
> >
> > Now I need to make some parallels so I can lay it down on the mill
> > table without taking out all the lock levers etc, and drill and tap
> > for the axle the intermediate stuff will turn on.  Then make the
> > shaft out of some .500" A2, figuring on some 8mm ID bearings if
> > torrington makes their needle 

Re: [Emc-users] Fwd: missing feature of openscad

[Chris Albertson]

On Wed, Jun 3, 2020 at 7:33 PM Gene Heskett  wrote:

> On Wednesday 03 June 2020 19:17:14 Chris Albertson wrote:
>
> > You are going to have to post a photo.  First off, I hope you are
> > printing these pulleys flat,  With rotational axis vertical.  I hate
> > to ask but with no photos we don't even know this.
> >
> > Assuming you are, the teeth are called "walls" and only if bubbles are
> > in the plastic would you get voids.Print slower or maybe cooler.
> > The outer wall layers should run at maybe 30 mm / second.
> >
> > Here is a cell-phone shot of a 30T GT2 profile pulley that has been
> > sitting around on my desk for a couple weeks.  It is dirty and the
> > flanges need to be cleaned up with a small nail file. The walls
> > are made in the direction of motion and are smooth enough.  It is a
> > 3mm tooth pitch by 9mm wide.I think this one was printed on "draft
> > mode" with 0.2mm layer height.   This is from an Anet A6 printer with
> > default settings in Cura. A steel hub goes in the 20mm hole.  THe gear
> > was downloaded from SPD/SI website than modified in Fusion 360
> >
> > [image: IMG_0542.jpg]
> Thats a heck of a lot nicer looking, and 10x smoother than what I have in
> my hand from this afternoons run.  That said, an XL belt fits it nicely.
> So this one is usable for a test fit mock up except the slot for the nut
> is about a 20% infill.  One might be able to epoxy it to the motor shaft
> with JBWeld. But despite 2mm walls around the hub, I can feel the
> elasticity and that bothers me.  And while I can sort of see the solid
> walls around the nut pocket, I have serious doubts of ever getting a
> decent grip because it will open up from the outward pressure the nut
> would exert.
>

Yes, That is why I make pulleys with a 20 or 24 mm hole.  They get epoxied
to a steel hub.   Steel hubs are easy to make on a lathe by hand.  I use
two set scres at 90 degrees.  I could epoxy to the motor shaft but then I
might want to use the motor later with a different pulley.

One thing that does work for a while,  If the motor has a "D" shaft or a
keyway you can print a D or keyway in the pulley.  D-holes don't spin but
the loose concentric over time.

There is one more technique I want to try.  Brass thread inserts.  You heat
these on a solder iron tht press them into a hole. When the plastic cools
they stick
amazon.com/Uxcell-a16041800ux0824-Knurled-Thread


If you have access to the backside you can press-fit normal hex nuts and
embed them into the plastic but these knured nuts press in from the front
side and might work for gears.   That would be quicker them making a steel
hub.  Kind of a compromise.   6 cents each.

Finally if you print threads, the wall and skin thrickness setting applies
to the  plastic around all holes, threaded of not

Use "preview" in Cura to see exactly how each layer will stack up



> So I'll probably use this as the motor pulley while I am mocking up the
> real drive, the next stage being a hubless, larger model, which will be
> epoxied to a smallish possibly herringboned gear, driving a much higher
> tooth count matching gear on the worm shaft. The herringbone may get
> lost in the translation to metal for the final parts though.
>
> I set up a "raft" for this one, and made it 15mm bigger than the hub, and
> it was 30 minutes just laying the raft. 4 layers.  Bed cold, I wiggled
> the putty knife under it, popped it off, then the raft separated nicely
> just like cura said it would. I upped the speed to 60mm/sec but I don't
> think it ever moved that fast. But I think a 5mm skirt would be ok and
> 20 minutes faster.
>
> Now I need to make some parallels so I can lay it down on the mill table
> without taking out all the lock levers etc, and drill and tap for the
> axle the intermediate stuff will turn on.  Then make the shaft out of
> some .500" A2, figuring on some 8mm ID bearings if torrington makes
> their needle cartridges that small, I haven't checked yet.  Need the
> smallest to make room for the relay gear to the bigger gear on the worm
> shaft.
>
> I got the motor adapter yesterday, a 34 to a 23, and I'll need to get
> another alu pulley with an 8mm bore to drive the Sheldons Z with the
> other motor.  Same tooth count, should move the Sheldon ok and 60 db
> quieter that the 1600 oz/in doing it now.  If I ever get a knee mill, it
> would make a good knee motor.  Better yet, somebody should make me an
> offer for it. 14mm shaft.
>
> Thanks Chris.
>
> > On Wed, Jun 3, 2020 at 1:37 PM Gene Heskett 
> wrote:
> > > On Wednesday 03 June 2020 14:54:31 Chris Albertson wrote:
> > >
> > >
> > > The pulley teeth are very low density, mostly air with a 

Re: [Emc-users] Fwd: missing feature of openscad

[Gene Heskett]

On Wednesday 03 June 2020 19:17:14 Chris Albertson wrote:

> You are going to have to post a photo.  First off, I hope you are
> printing these pulleys flat,  With rotational axis vertical.  I hate
> to ask but with no photos we don't even know this.
>
> Assuming you are, the teeth are called "walls" and only if bubbles are
> in the plastic would you get voids.Print slower or maybe cooler. 
> The outer wall layers should run at maybe 30 mm / second.
>
> Here is a cell-phone shot of a 30T GT2 profile pulley that has been
> sitting around on my desk for a couple weeks.  It is dirty and the
> flanges need to be cleaned up with a small nail file. The walls
> are made in the direction of motion and are smooth enough.  It is a
> 3mm tooth pitch by 9mm wide.I think this one was printed on "draft
> mode" with 0.2mm layer height.   This is from an Anet A6 printer with
> default settings in Cura. A steel hub goes in the 20mm hole.  THe gear
> was downloaded from SPD/SI website than modified in Fusion 360
>
> [image: IMG_0542.jpg]
Thats a heck of a lot nicer looking, and 10x smoother than what I have in 
my hand from this afternoons run.  That said, an XL belt fits it nicely.  
So this one is usable for a test fit mock up except the slot for the nut 
is about a 20% infill.  One might be able to epoxy it to the motor shaft 
with JBWeld. But despite 2mm walls around the hub, I can feel the 
elasticity and that bothers me.  And while I can sort of see the solid 
walls around the nut pocket, I have serious doubts of ever getting a 
decent grip because it will open up from the outward pressure the nut 
would exert.

So I'll probably use this as the motor pulley while I am mocking up the 
real drive, the next stage being a hubless, larger model, which will be 
epoxied to a smallish possibly herringboned gear, driving a much higher 
tooth count matching gear on the worm shaft. The herringbone may get 
lost in the translation to metal for the final parts though.

I set up a "raft" for this one, and made it 15mm bigger than the hub, and 
it was 30 minutes just laying the raft. 4 layers.  Bed cold, I wiggled 
the putty knife under it, popped it off, then the raft separated nicely 
just like cura said it would. I upped the speed to 60mm/sec but I don't 
think it ever moved that fast. But I think a 5mm skirt would be ok and 
20 minutes faster.

Now I need to make some parallels so I can lay it down on the mill table 
without taking out all the lock levers etc, and drill and tap for the 
axle the intermediate stuff will turn on.  Then make the shaft out of 
some .500" A2, figuring on some 8mm ID bearings if torrington makes 
their needle cartridges that small, I haven't checked yet.  Need the 
smallest to make room for the relay gear to the bigger gear on the worm 
shaft.

I got the motor adapter yesterday, a 34 to a 23, and I'll need to get 
another alu pulley with an 8mm bore to drive the Sheldons Z with the 
other motor.  Same tooth count, should move the Sheldon ok and 60 db 
quieter that the 1600 oz/in doing it now.  If I ever get a knee mill, it 
would make a good knee motor.  Better yet, somebody should make me an 
offer for it. 14mm shaft.

Thanks Chris.

> On Wed, Jun 3, 2020 at 1:37 PM Gene Heskett  
wrote:
> > On Wednesday 03 June 2020 14:54:31 Chris Albertson wrote:
> >
> >
> > The pulley teeth are very low density, mostly air with a filament
> > bridge at a 45 degree angle.  How do solidify the teeth? What I'm
> > getting would cut up an XL belt in an hours work, its that sharp.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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