File Formats, Compatibility, and Open Source

Hello,

Before I begin, please bear in mind that I have no CAD experience so maybe the problem is me. However, I have a reasonable amount of experience with open-source software so I have an appreciation of the challenge.

Recently, I was directed to some RepRap-related .dxf files that I was interested in looking at. I downloaded no less than 4 different programs that claimed to be able to read these formats. None of them would read these files. After doing a little research, I found that .dxf is an AutoCad format and it is subject to change.

While I understand and fully appreciate that people should be able to use the tools that they have available to them to support an open-source project, I have to question the compatibility issues. For example, a lot of open-source software is written in C or C++. This source code is readable by anything from a simple text editor (i.e. Notepad) to a $500 (or more) integrated development environment. Then, it can usually be compiled with a variety of compilers ranging from Microsoft's Visual Studio to the open-source and zero cost gcc. (Over the last few years, Microsoft has even made a version of it's compiler available for free.)

Why do I need to buy a $4,000 CAD program to read "open-source" RepRap related blueprints?

Regards,

Brian

Good points. This is one of the reasons why great projects like OpenSCAD parameterized mendel is started.

Though so far I've been able to look at the official designs with the supplied .stl files through Wings3D or OpenSCAD. Not optimal as the triangulation process makes the models hard to modify, but it is often sufficient if all you want is a closer look.

---

--
-Nudel
Blog with RepRap Comic

Quote

Why do I need to buy a $4,000 CAD program to read "open-source" RepRap related blueprints?

You don't. You can always ask the creator or a friend to do the conversion for you. 3D-DXF isn't, and probably never was, state of the art. AutoDesk's 3D product is Inventor (with yet another proprietary format). Ask for STL or (better) STEP files.

The problem with mechanics is, there is no bash and no gcc equivalent. Open source CAD is currently about 20 years behind the commercial competition. Some well working applications like Blender exist, but they're meant for rendering, and inferior for technical stuff. Other's, like BRL-CAD, OpenSCAD, FreeCAD, HeeksCAD, and a few more exist, but they're very very young.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Hello,

Actually, your argument helps to make my point.

I need to be able to contact the creator in order to get the file converted to more easily read file format. But, the creator may not respond, be on vacation, or could have gotten hit by the proverbial bus. I also have the option asking a friend, with access to the $4,000 CAD program, to convert the file for me. (Don't we all have a friend with access to a $4,000 CAD program?) Or, I can just write a check for $4,000 and buy the CAD program so I can read the files. (Assuming that I have the money and would part with it for this purpose.)

In another analogy, making a .dxf file available is similar to me giving you a file stored on an 8 inch floppy disk. If you don't have an 8 inch floppy drive, just ask a friend to copy it to a USB drive for you.

I understand that there is no equivalent to AutoCAD as there is gcc to MS Visual Studio. But, there are .jpg, .pdf, .png, etc. files that can be read by almost anything. In addition, most software to read these formats is free. A simple saved screen shot of each view, with dimensions, would suffice. If AutoCAD has the capability to save the files in other formats, that would be even better.

In my opinion, a proprietary file format, such as a .dxf file, has more in common with a compiled program than it does with source code. In order to read a compiled program I need an expensive disassembler and in order to read a .dxf file I need an expensive application. (Though, in all fairness, the "source code" generated by the disassembler isn't as good as having the original source code.)

Please also consider that in many parts of the world $4,000 is more than a yearly wage. On one hand, RepRap is advertised as being "Wealth Without Money" and on the other hand you need $4,000 in order to obtain information on how to create "Wealth Without Money."

Regards,

Brian



Traumflug Wrote:
-------------------------------------------------------
> Why do I need to buy a $4,000 CAD program to read
> "open-source" RepRap related blueprints?
>
> You don't. You can always ask the creator or a
> friend to do the conversion for you. 3D-DXF isn't,
> and probably never was, state of the art.
> AutoDesk's 3D product is Inventor (with yet
> another proprietary format). Ask for STL or
> (better) STEP files.
>
> The problem with mechanics is, there is no bash
> and no gcc equivalent. Open source CAD is
> currently about 20 years behind the commercial
> competition. Some well working applications like
> Blender exist, but they're meant for rendering,
> and inferior for technical stuff. Other's, like
> BRL-CAD, OpenSCAD, FreeCAD, HeeksCAD, and a few
> more exist, but they're very very young.

The issue with jpg and png it that they're pixel based, the issue with pdf is that it's a typesetting and lyout format. So, they are not a suitable format for this use. However I see on reason not to use svg. Its an open standard, it's supported by all modern browsers and image editors and whatnot. That's what I am using for distribtung my midified mounting plate design on thingiverse for the tech zone electronics.

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----------------------------------------------------
Build Progress Blog

reifsnyderb Wrote:

> Actually, your argument helps to make my point.

Actually, you're barking up the wrong tree. It isn't me who offers files in DXF format, neither is DXF the RepRap recommended format.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Hello,

That is a very good point. Maybe I should have posted this to the MakerBot forum. I just double-checked and the files, in question, are located here: [svn.makerbot.com]

I also found the list of RepRap software does not contain AutoCad: [www.reprap.org]

My primary issue is that if there is some sort of compatibility problem with reading "open-source" files, then are they really "open-source"? Is it really "open-source" if I need a $4,000 program to look at it? If I need to spend that sort of money to view the source then isn't this similar to paying some company in order to view the source code to their software? Is the question an issue of money? Is it ok to use a $20.00 program to view the source code; but not ok to use a $4,000 program? Where is the "line" drawn?

In the software world, open-source software source code can be viewed with other open-source software.

Regards,

Brian



Traumflug Wrote:
-------------------------------------------------------
> reifsnyderb Wrote:
>
> > Actually, your argument helps to make my point.
>
> Actually, you're barking up the wrong tree. It
> isn't me who offers files in DXF format, neither
> is DXF the RepRap recommended format.

Brian,

Adrian and Ed originally did up Darwin in Solid Edge (payware) and then immediately ported it to Art of Illusion (GPL).
Art of Illusion, which is GPL.

Likewise with Mendel: http://reprap.org/wiki/Mendel/Files has the Solid Edge, AOI, and .stl files you are looking for.

There are some .blend files of Mendel around, but those aren't in the wiki because the developer who did them up didn't put them in the wiki.

In the software world, open-source software source code can be viewed with other open-source software.
We know. We care about this too.

Along those lines, I was wondering, do you feel up to writing up any of your nozzles in the wiki, which would instantly make them Official RepRap Documentation(™)? Please let me and the other library gnomes know if you need any help with that.

Edited 1 time(s). Last edit at 06/23/2010 07:23PM by SebastienBailard.

---

-Sebastien, RepRap.org library gnome.

---

Remember, you're all RepRap developers (once you've joined the super-secret developer mailing list), and the wiki, RepRap.org, [reprap.org] is for everyone and everything!

Hello,

Thanks for the explanation.

But, I think MakerBot is supposed to be an "open source" company and that doesn't explain why those files are in the .dxf format.

Since I have my blueprints scrawed in a notebook, I'll get my nozzles, thermal barrier designs, idler pulley, etc. drawn up nicely and scan them in into a standard format. (Probably .jpg or .pdf) Can I send them to you for posting?

You've got me on this one. I'd look like quite the hypocrite if I didn't post the designs somewhere.
(Though, I have provided information upon request.)

Regards,

Brian



SebastienBailard Wrote:
-------------------------------------------------------
> Brian,
>
> Adrian and Ed originally did up Darwin in Solid
> Edge (payware) and then immediately ported it to
> Art of Illusion (GPL).
> Art of Illusion, which is GPL.
>
> Likewise with Mendel:
> [reprap.org] has the Solid
> Edge, AOI, and .stl files you are looking for.
>
> There are some .blend files of Mendel around, but
> those aren't in the wiki because the developer who
> did them up didn't put them in the wiki.
>
> In the software world, open-source software source
> code can be viewed with other open-source
> software.
> We know. We care about this too.
>
> Along those lines, I was wondering, do you feel up
> to writing up any of your nozzles in the wiki,
> which would instantly make them Official RepRap
> Documentation(™)? Please let me and the other
> library gnomes know if you need any help with
> that.

You've got me on this one. I'd look like quite the hypocrite if I didn't post the designs somewhere.
Nah, I think that makes you a RepRap developer. We're occasionally silly, often "too busy to document", and always quixotic, but we're never hypocrites.

(Though, I have provided information upon request.)
Then you're in compliance with the GPL. Just like Foton:
[forums.reprap.org]


Since I have my blueprints scrawed in a notebook, I'll get my nozzles, thermal barrier designs, idler pulley, etc. drawn up nicely and scan them in into a standard format. (Probably .jpg or .pdf) Can I send them to you for posting?
Sure. Until we have Big_Fat_Upload_Button technology up and running, that will work.

Still, you may want to try creating a new page, by clicking and editing this page
http://reprap.org/wiki/Mister_Nozzle
or
http://reprap.org/wiki/My_Nozzle_Name

as per the instructions here:
http://reprap.org/wiki/Development
http://reprap.org/wiki/Example
and when you run into trouble, ping me and the other library gnomes and we'll help. Or email me the files at penguin at supermeta dot com if you can't get the wiki to work. I think jpgs will be more useful than pdfs, in our case.

But, I think MakerBot is supposed to be an "open source" company and that doesn't explain why those files are in the .dxf format.
I think that's my cue to launch into a long essay about the realpolitick of open source hardware development and how it relates to ethics, web-technology and the power of marketing and names. I'll spare you, because it will be a derail.

I will point out that all the cool kids are building WolfStraps and LaserCut Mendels now.

That said, we have some documentation and files here http://reprap.org/wiki/CupCakeStrap that should be helpful.

But I'd suggest building a WolfStrap.

Edited 1 time(s). Last edit at 06/23/2010 09:33PM by SebastienBailard.

---

-Sebastien, RepRap.org library gnome.

---

Remember, you're all RepRap developers (once you've joined the super-secret developer mailing list), and the wiki, RepRap.org, [reprap.org] is for everyone and everything!

You could give edrawings a shot: [www.edrawingsviewer.com]

It might be able to open and view your .dxf files.

In general, there is no standard for CAD the way there is for computer code. So while you can open a C++ project in Eclipse, Microsoft Visual Studio, devC++, notepad++, or notepad, and have it all be essentially identical, that's not the case for a 3D CAD file.

DXF is an industry standard 2-dimensional vector format, so almost any vector image program should be able to open it. 3D-DXF is not, however.

Of course, 3D models are much more complicated than text-based computer code, so there's a reason you can't open a 3D model in notepad...

"reifsnyderb"

"Recently, I was directed to some RepRap-related .dxf files that I was interested in looking at. I downloaded no less than 4 different programs that claimed to be able to read these formats. None of them would read these files. After doing a little research, I found that .dxf is an AutoCad format and it is subject to change. "

So did you try to read the DXF files with FreeCad? How about Inkscape using the DXF plugin?

DXF is a 2D Cad exchange format and whilst there are variations it should be possible to exchange files.
Maybe there is a problem with the original DXF files.

Most of the applications claiming to import DXF do 2D CAD. This is of no use for 3D models.

---

Generation 7 Electronics	Teacup Firmware	RepRap DIY

... for 2D-DXF exporting-importing issues you have to check the aimed ACAD-version compatibility - i have best experiences with ACAD14/ACAD2000, but even then you have some incompatibilities with curves ... either splines or beziers or polygons

3D-DXF is even more version-dependant ...

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

reifsnyderb: The MakerBot DXF files are 2D only and captured using QCad - [www.qcad.org]. It's dual-licensed for both commercial (aka closed-source API access) and GPL compiling+forking, as is the underlying "dxflib" API itself that reads and writes the DXF: [www.qcad.org]

Thanks, but I tried edrawings...it didn't work.

Regards,

Brian


jbayless Wrote:
-------------------------------------------------------
> You could give edrawings a shot:
> [www.edrawingsviewer.com]
>
> It might be able to open and view your .dxf
> files.
>
> In general, there is no standard for CAD the way
> there is for computer code. So while you can open
> a C++ project in Eclipse, Microsoft Visual Studio,
> devC++, notepad++, or notepad, and have it all be
> essentially identical, that's not the case for a
> 3D CAD file.
>
> DXF is an industry standard 2-dimensional vector
> format, so almost any vector image program should
> be able to open it. 3D-DXF is not, however.
>
> Of course, 3D models are much more complicated
> than text-based computer code, so there's a reason
> you can't open a 3D model in notepad...

Hello,

I started uploading. Right now, I'll do one or two as I get the time. So far, I have uploaded a standard PTFE or PEEK thermal barrier and a PEEK groove-mount thermal barrier. I'll do the hybrid designs next.

I made a page just for all of my thermal barrier designs: [reprap.org] For the most part, they are just improvements on the current design.

I drew them up with MS Paint and converted them to .jpg images with GIMP.

Regards,

Brian



SebastienBailard Wrote:
-------------------------------------------------------
> You've got me on this one. I'd look like quite the
> hypocrite if I didn't post the designs somewhere.
> Nah, I think that makes you a RepRap developer.
> We're occasionally silly, often "too busy to
> document", and always quixotic, but we're never
> hypocrites.
>
> (Though, I have provided information upon
> request.)
> Then you're in compliance with the GPL. Just like
> Foton:
> [forums.reprap.org]
> g-49643
>
>
> Since I have my blueprints scrawed in a notebook,
> I'll get my nozzles, thermal barrier designs,
> idler pulley, etc. drawn up nicely and scan them
> in into a standard format. (Probably .jpg or .pdf)
> Can I send them to you for posting?
> Sure. Until we have Big_Fat_Upload_Button
> technology up and running, that will work.
>
> Still, you may want to try creating a new page, by
> clicking and editing this page
> [reprap.org]
> or
> [reprap.org]
>
> as per the instructions here:
> [reprap.org]
> [reprap.org]
> and when you run into trouble, ping me and the
> other library gnomes and we'll help. Or email me
> the files at penguin at supermeta dot com if you
> can't get the wiki to work. I think jpgs will be
> more useful than pdfs, in our case.
>
> But, I think MakerBot is supposed to be an "open
> source" company and that doesn't explain why those
> files are in the .dxf format.
> I think that's my cue to launch into a long essay
> about the realpolitick of open source hardware
> development and how it relates to ethics,
> web-technology and the power of marketing and
> names. I'll spare you, because it will be a
> derail.
>
> I will point out that all the cool kids are
> building WolfStraps and LaserCut Mendels now.
>
> That said, we have some documentation and files
> here [reprap.org] that
> should be helpful.
>
> But I'd suggest building a WolfStrap.

Hello,

I didn't try those packages. I'll try them when I get some more time.

Regards,

Brian


KeithSloan Wrote:
-------------------------------------------------------
> "reifsnyderb"
>
> "Recently, I was directed to some RepRap-related
> .dxf files that I was interested in looking at. I
> downloaded no less than 4 different programs that
> claimed to be able to read these formats. None of
> them would read these files. After doing a little
> research, I found that .dxf is an AutoCad format
> and it is subject to change. "
>
> So did you try to read the DXF files with FreeCad?
> How about Inkscape using the DXF plugin?
>
> DXF is a 2D Cad exchange format and whilst there
> are variations it should be possible to exchange
> files.
> Maybe there is a problem with the original DXF
> files.

I wonder if this is the problem. Maybe the .dxf is 3d?



Traumflug Wrote:
-------------------------------------------------------
> Most of the applications claiming to import DXF do
> 2D CAD. This is of no use for 3D models.

I'll try that one...maybe it is QCad.

Thanks,

Brian


clothbot Wrote:
-------------------------------------------------------
> reifsnyderb: The MakerBot DXF files are 2D only
> and captured using QCad - [www.qcad.org].
> It's dual-licensed for both commercial (aka
> closed-source API access) and GPL
> compiling+forking, as is the underlying "dxflib"
> API itself that reads and writes the DXF:
> [www.qcad.org]

I started uploading. Right now, I'll do one or two as I get the time. So far, I have uploaded a standard PTFE or PEEK thermal barrier and a PEEK groove-mount thermal barrier. I'll do the hybrid designs next.

I made a page just for all of my thermal barrier designs: [reprap.org] For the most part, they are just improvements on the current design.

Wonderful, thank you!

I drew them up with MS Paint and converted them to .jpg images with GIMP.

Your workflow obviously works, but you may find qcad handy for drafting nozzles.

I've been meaning to get into Free Cad myself. Has anyone tried their 2D drafting functions?

Edited 1 time(s). Last edit at 06/24/2010 05:08PM by SebastienBailard.