Solid Model files for Prusa Mendel

Hi All,
Ive been following the builds for a couple of years now.
I believe that I am ready to begin a Prusa Mendel.
I would like to first build a sloid model of the entire assembly. Is there one available for download?
If not are there individual parts that I can download to then create the assembly.
I'm using Solid Edge which is a program very simiar to Solid Works
Thanks for any help,
Peter

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Pedro B
Maine USA

[reprap.org]

there are four stl files there with all the printed parts. you may have to go through the build instructions to put this together in solid edge and grab the standard parts(rods, screws, bushings) from the web as you go.

Note those parts are an older version, I recommend you use the updated model files from here: [github.com]

You can find an excellent assembled sketchup model of the old version here: [github.com] (in the scr/models directory)

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-Nudel
Blog with RepRap Comic

If you're planning on building the latest version of the Prusa (v2) then I created a set of Google Sketchup parts from the STL's a little while back: [sketchup.google.com]

They will have changed in the meantime, so of course your best bet is to get the STLs from the github project and import them in some way.

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garyhodgson.com/reprap | reprap.development-tracker.info | thingtracker.net

Not sure how to get to the .stl files on github. Can someone provide a link.
The .stl will import directly into solid edge?
Thanks for any help...

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Pedro B
Maine USA

The metric STL files...
[github.com]


A rudimentary google seems to indicate that Solid Edge can only import STL files via a non-free plugin, as is the Google Sketchup (.skp) importer.

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garyhodgson.com/reprap | reprap.development-tracker.info | thingtracker.net

The STEP directory in my repository for my fork of the Prusa has STEP models converted from .stl files I took just after Prusa 2 was announced. If you want more current models, and can import STEP files, then you can use FreeCAD as an intermediary to make STEP from current stl files.

OK I'm really showing my inexperiance with navigating the file system at github.
If i click on a file i get a view of many lines of text.
if I click on the file icon i'm prompted to save the file to the clipboard.
where is the clipboard and how the heck do i get an .stl or any other file type to download so that i can open it up with solid edge?

If you just want the files, click on download and fetch the entire branch in a zip or tar file.

That said, it's very much worth it to learn the basics of git.

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-Nudel
Blog with RepRap Comic

The wiki page for Prusa Mendel [reprap.org] has solid works files at [rusa_Mendel_Solidworks_2007_Assembly.zip" target="_blank" rel="nofollow">reprap.org]

Not sure how upto date the file are says created March 2011

Stl files might be okay for printing and maybe even construction, but not so useful if you want
to do any 3D Cad work on them. STL is really just a mesh output format. But unfortunately the
community does not use 3D cad files. I wish more people would use FreeCad and distribute 3D cad files,
like STEP.

Converting STL to STEP does not really help much.

Edited 1 time(s). Last edit at 02/27/2012 10:14AM by KeithSloan.

The reprap community has adopted openscad and git for its DNA. It has the massive advantage that it can be handled by software source control and you can branch and merge 3D designs.

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[www.hydraraptor.blogspot.com]

OpenSCAD is fine if you like programming. Some of us do NOT and would prefer to use 3D cad software

Fine, but anything moved out of openscad into 3D cad will never get merged back in, so will become a dead end branch.

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[www.hydraraptor.blogspot.com]

Sorry duplicate, cos I got a spam warning message that my post had been block.

Edited 1 time(s). Last edit at 02/27/2012 12:56PM by KeithSloan.

Trouble is OpenSCAD only exports to STL and not to any recognized 3D Cad format. So not easy to modify via 3D cad software.

Nophead you might like to check out this thread in the FreeCad forum [sourceforge.net]

FreeCad also has programming like OpenSCAD as well as creating things via GUI. Some claim the language is more powerful than OpenSCAD. They have more or less created MendelMax via FreeCad programming.

They are still missing assembly of parts, but that is apparently happening.

FreeCAD would seem to have the benefits of either programming or GUI and also the ability to output files to STEP et al.

Yes but would parts designed in the GUI be represented by code that could be subsequently edited as code?

I think Openscad not exporting to STEP is a good thing. It stops people taking Reprap designs and moving them into a locked CAD system. People would hack on the parts with their favourite CAD system and then they could never be converted back to code and differenced and merged with the originals. Openscad and git promote collaboration and evolution of designs.

Openscad is a purely declarative language, which is why it doesn't have true variables. A lot of people don't seem to "get" that but if makes perfect sense when you are describing what form something has rather than how to do something. I didn't miss having variables when I did the Mendel90 design.

Edited 1 time(s). Last edit at 02/27/2012 05:29PM by nophead.

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[www.hydraraptor.blogspot.com]

This conversation is kind of funny. No disrespect to any parties at all. Its just that I had recently posted some files on thingiverse and got the beat down for not using openscad. People couldn't use my stl's and thought that I was wrong for not using the adopted format.

I use solidworks on a daily basis for a living. I actually own my own seat. Not a big deal, but it keeps me using it (payed good money for it, right?). I won't walk away from that investment, much like I wouldn't ask others to buy solidworks.

Funny thing is, all of my files were stl's off of git and in order for me to be able to use them I had to recreate the parts by tracing the geometry and building solid models.

Sure, it was a bit of work, but I didn't browbeat anybody for not providing igs files or .sldprt for my benefit. I just traced, cleaned up the geo and made parametric files that I could use/modify.

I'm not saying that I won't someday try to fit in and learn the language. Just that I already am profficient in a different one and am busy catching up on the other aspects of reprap.

I don't know solidworks, but using a mesh modeller like wings3D with a few tricks up its sleeve, it's really quite trivial - depending on the model - to clean up stl outputs from openscad so it's easier to modify them with other cad tools.

To be honest, I love openscad, but due to its nature the stl output can be just horrible. Not worse than sketchup perhaps, but still enough for it to be visible on the print if the slicing software get in trouble.

Not saying everyone should have to learn to use a mesh modeller and make triangle-perfect stl files, but sometimes the files on thingiverse is so bloated and messed up it's not worth the time to try and print them if you get errors.

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-Nudel
Blog with RepRap Comic

KeithSloan Wrote:
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> OpenSCAD is fine if you like programming. Some of
> us do NOT and would prefer to use 3D cad software

So true. That being said, FreeCAD can turn an .stl part into a CAD solid. Import the .stl, and select it in the file tree, go to the part menu and select "create shape from mesh". This'll bring up a tolerance dialogue, which shouldn't really matter if the .stl is watertight. Then select the shape that's appeared in the file tree, go back to the part menu and check the "convert to solid" item, and the resultant solid will appear in the part list. That entity can be edited as a solid in FreeCAD, or exported as a .stp part to be imported into other apps. The only thing that's mildly annoying is that the .stl face definitions remain. Some commercial CAD apps consolidate coplanar triangles into a single face, which looks prettier. The other thing to bear in mind is that holes in an .stl, or a solid that's been made from it, are faceted approximations, and the important thing is clearance. The diameter of the holes has to be derived from a cylinder that fits within the polygonal hole definition, ie from the mid-points of the hole exit's edges.
Other mesh formats like 3DS, dxf or obj can be turned into solids in the same way, but only if they're manifold, watertight, objects. .3DS, .dxf and .obj can be surface meshes, which won't convert to solids.

Edited 2 time(s). Last edit at 02/28/2012 07:55AM by murrayd.

The hole diameter is where the vertices are, not the midpoint of the lines.

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[www.hydraraptor.blogspot.com]

That's not right. A 3mm screw won't fit through a polygon that's circumscribed by a 3mm circle. The clearance circle is circumscribed by the polygon, not the other way round.

Yes but never the less that is what CAD systems do when they make STL files, try it.

That is one of the many reasons holes come out too small.

Edited 2 time(s). Last edit at 02/28/2012 10:30AM by nophead.

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[www.hydraraptor.blogspot.com]

I capitulate! I was describing reversing an .stl back to CAD solid, but I can agree that hole clearance is a trap.

It's one of the reasons I like OpenScad. All my vertical holes in plastic parts are polyholes, so I control the number of facets and where the vertices are.

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[www.hydraraptor.blogspot.com]

Pretty much any CAD system can, GUI or not. I've no nostalgic affection for command lines and syntax rules, retracing (drafting pun warning) that ground is unappealing.

Lets face facts. You wouldn't use OpenSCAD if a proper CAD system was on the market for an affordable price.

I haven't yet downloaded a .stl model from thingiverse that wasn't awful and had surface errors. They are all incorrectly scaled (usually 25.4 x bigger due to imperial / metric conflicts). The .stl file is also massive when imported to another CAD system which can cause issues. As a further problem they seems to be an ascii/binary format problem.

In order to pull these to CATIA V5 which I use I have to take them into blender to overcome the ascii/binary problem, export them, convert them to iges using a dos converter, then pull them into CATIA, then scale them down and remodel the surfaces. A real pain.

To store your designs in .stl format has the only advantage that they are directly printable. A better format would be .iges which although old is very good for most CAD systems and relatively simple to code. An alternative would be .step files which is rapidly becoming an industry prefered standard.

Quote

Lets face facts. You wouldn't use OpenSCAD if a proper CAD system was on the market for an affordable price.

It would have to be multi-platform and open source.

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[www.hydraraptor.blogspot.com]

I still would use it, but maybe that's because I'm (payed for pretending to be) a programmer.

Also on the learning curve side, any cad system, even proper, would take me a lot of time to learn using, while I was able to immediately start using openscad efficiently as soon I installed it.

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Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.

I used CoCreate first and that was very easy to learn but I haven't used it since I learn't OpenScad. Perhaps its because I am a programmer, but I think doing 3D with scripts is far more powerful than using a GUI. It takes longer initially but then it pays back as you reuse it and modify things.

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[www.hydraraptor.blogspot.com]