# Specific 3D Printers, Scanners, & Hardware > Other 3D Printers / Scanners / Hardware >  File Conversion Solution from STL (3D) to CSV (series of layered bitmap)

## pasecaille

Hello, I have acces to a Voxeljet sand/binder 2.5D printer. Its custom interface only reads bitonal bitmap images, one at a time. For more complex forms, it can optionally read a CSV (excel-type table) of ordered layers of PBM (bitmaps). On Rhino one can export as STL for a number of printing solutions. However, to my knowledge, it cannot export more than one image file and unfortunately only as jpg (not as PBM or bmp). I've automated contours at successive heights of thickness, but I don't know how to export as a series of bitmap PBM into a CSV file. Does anyone know a single program solution? It would be great to script this through Grasshopper. Any ideas would be appreciated. Thanks in advance for your thoughts.

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## curious aardvark

Umm, doesn't the machine use a slicer of any kind ? 

usually the slicer reads the stl file and then converts it into the layer file that the printer then uses to make the object. 

Hmm, not much comes up on a web search - except the fact that you've asked the same question on about 10 different fourms ;-) 

Surely the machine must come with software of some description that lets you print things.

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## pasecaille

Hello curious aardvark, thanks for responding.  
This was apparently a prototype sand/binder printer.  It's software is based on Rapix3D which only reads PBM (bitmaps) individually, or a series of PBM files representing each layer organised in a CSV (excel-type file).  It has no way of identifying a STL file.  Unfortunately there are no "slicer" functions....

The 2.5D printer spreads out a layer of sand, prints the bitmap with a binding fluid, then recoats the next layer over it to print the next layer image. The unprinted sand is removed and remains the printed "3d model".

I'm awaiting response from the creator of this machine, but I feel as though they are avoiding this issue.  So I thought of taking matters into my own inexperienced hands. 

I haven't found anything via google to answer this need which explains the proliferation among forums (or is it _fora_?)  So it appears I may have to "hack it". 

It needs to be automated to an extent, since I will produce several elements (roughly 25), each with around 100 layers.  As of now, I can export a single layer onto Illustrator, fill it, then, save as a single bitmap. But I don't know how to make a CSV from an existing PBM (bitmap) and add on to it 99 other bitmaps....

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## curious aardvark

there will be software for it. The developers would not have buggered about with bitmap files.

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## cbernhardt

Interesting printer!  Could you post a picture of one of your project prints?
Just out of curiosity (because I used to be an AutoCad developer writing contouring software for land development), in what format is your original contour data?

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## pasecaille

The designer confirmed that they have no other software for this model of printer.  
Unfortunately the software for this model reads only PBM (bitonal bitmap b&w) images individually or a series of bitmaps in a CSV file (spreadsheet).

So I'll have to find a way to convert the 3D model (vector -based) into a series of bitmap (raster-based) and organize them into a CSV file.

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## cbernhardt

In what format is the original 3D model?

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## pasecaille

> In what format is the original 3D model?


It's an OBJ, but I could export as an STL...

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## cbernhardt

OK, extracting the data from an OBJ or STL file and converting to a PBM should not be a great problem, but I am not sure how the PBM data should be arranged in a CSV file.  The data in a PBM file is basically a representation of a monochrome raster image arranged in rows and columns of ones and zeros.  I can guess how you could place the data for one layer in a CSV, but I would think that there must also be some elevation data added for multiple layers.  Do you have an example of the CSV file that would be required to print multiple layers?

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## pasecaille

> OK, extracting the data from an OBJ or STL file and converting to a PBM should not be a great problem, but I am not sure how the PBM data should be arranged in a CSV file.  The data in a PBM file is basically a representation of a monochrome raster image arranged in rows and columns of ones and zeros.  I can guess how you could place the data for one layer in a CSV, but I would think that there must also be some elevation data added for multiple layers.  Do you have an example of the CSV file that would be required to print multiple layers?


cbernhardt, thanks for your answer.  The below example is the disposition of data in the CSV file  "Anzahl" is number of times the printer passes, "Schicht Hoehe" is the layer height.  I'm not sure yet if the offset is in y- or x-axis…

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## cbernhardt

I do not see the file.  Could you email me the CSV file and the corresponding OBJ file?
email: charlie@carols62.com

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## pasecaille



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## cbernhardt

Still not seeing the link to the CSV file in your post.
In my email notification of your post there is this link but the address is invalid: 
http://3dprintboard.com/webkit-fake-...715/image.tiff

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