Problems Printing Case for Portable Raspberry Pi

Hey guys,

This is my first post so sorry if it's in the wrong section. I am trying to create a portable Raspberry Pi as part of my senior project in college and am taking a stab at 3D printing a case for it. I designed a case in Google SketchUp and exported it as a .stl file. I do not personally have a 3D printer but our IT department on campus does. I submitted the design to them so they could try printing it and apparently all the sections that are supposed to be hollow are printing as a solid block. I was also told that the design takes a very long time to compile. I believe they are using a MakerBot printer but I don't know the specific model. I'll post my designs below (both the SketchUp file and .stl) and hopefully someone can tell me what is wrong with them. This is my first attempt at designing something to be 3D printed so I'm not sure exactly what to look for. Any help would be greatly appreciated!

https://www.dropbox.com/s/eey3h9unm9...ablePiCase.zip

When I get the chance I'll download the stl and take a look at it, see if there's a problem with the geometry or the slicing software your university is using.

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Originally Posted by Eric052492

Hey guys,

This is my first post so sorry if it's in the wrong section. I am trying to create a portable Raspberry Pi as part of my senior project in college and am taking a stab at 3D printing a case for it. I designed a case in Google SketchUp and exported it as a .stl file. I do not personally have a 3D printer but our IT department on campus does. I submitted the design to them so they could try printing it and apparently all the sections that are supposed to be hollow are printing as a solid block. I was also told that the design takes a very long time to compile. I believe they are using a MakerBot printer but I don't know the specific model. I'll post my designs below (both the SketchUp file and .stl) and hopefully someone can tell me what is wrong with them. This is my first attempt at designing something to be 3D printed so I'm not sure exactly what to look for. Any help would be greatly appreciated!

https://www.dropbox.com/s/eey3h9unm9...ablePiCase.zip

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Give Netfabb Cloud a try, it's designed specifically to fix issues like that. I use without fail everytime before I print a new mesh I've made, avoid wasted prints.

https://netfabb.azurewebsites.net/

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Originally Posted by Eric052492

Hey guys,

This is my first post so sorry if it's in the wrong section. I am trying to create a portable Raspberry Pi as part of my senior project in college and am taking a stab at 3D printing a case for it. I designed a case in Google SketchUp and exported it as a .stl file. I do not personally have a 3D printer but our IT department on campus does. I submitted the design to them so they could try printing it and apparently all the sections that are supposed to be hollow are printing as a solid block. I was also told that the design takes a very long time to compile. I believe they are using a MakerBot printer but I don't know the specific model. I'll post my designs below (both the SketchUp file and .stl) and hopefully someone can tell me what is wrong with them. This is my first attempt at designing something to be 3D printed so I'm not sure exactly what to look for. Any help would be greatly appreciated!

https://www.dropbox.com/s/eey3h9unm9...ablePiCase.zip

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Give Netfabb Cloud a try, it's designed specifically to fix issues like that. I use without fail everytime before I print a new mesh I've made, avoid wasted prints.

https://netfabb.azurewebsites.net/

Also I just sliced your model and it isnt set as hollow and your faces are the wrong way on some vertices (or normals as they are called) they all need to be facing outward. I use blender, makes that stuff easy.

(P.S I did edit my previous post, but Vbulletin decided to create a second post... very odd)

http://www.devogeninteractive.com/pi...A_5345CAFA&jpg

There are a few faces in the sketchup files that need reversing - they're internal rather than external. The default colour scheme makes it a little difficult to pick them out, but you can change the settings to make it easer.

Load up the files in Sketchup and go to Window - Styles. Click on the Select tab (should already be selected) and choose Color Sets in the combo box. Click on one of the colour sets that has a good level of contrasting colour that makes internal and external faces easy to distinguish. The list will show a number of graphics with different options. The larger object in each graphic illustrates the external face colour and the smaller the internal face. Choose the one you like best.

You should then be able to readily distinguish internal and external faces in your objects. Protip: you should not be able to see an internal face, as each of these should be facing inside a solid object. Right-click on each one and select "Reverse Faces." Once you've done each one you can see (there aren't many), export to STL and you should be hot to trot, although I'd recommend using the netfabb cloud service to make sure.

Sorry if this is over-explaining it but it's difficult to pitch to the right level.

Thanks for the responses guys! I need to get a little bit of work out of the way but I will around with your suggestions later tonight. I'll post back afterwards.

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Originally Posted by 3dkarma

There are a few faces in the sketchup files that need reversing - they're internal rather than external. The default colour scheme makes it a little difficult to pick them out, but you can change the settings to make it easer.

Load up the files in Sketchup and go to Window - Styles. Click on the Select tab (should already be selected) and choose Color Sets in the combo box. Click on one of the colour sets that has a good level of contrasting colour that makes internal and external faces easy to distinguish. The list will show a number of graphics with different options. The larger object in each graphic illustrates the external face colour and the smaller the internal face. Choose the one you like best.

You should then be able to readily distinguish internal and external faces in your objects. Protip: you should not be able to see an internal face, as each of these should be facing inside a solid object. Right-click on each one and select "Reverse Faces." Once you've done each one you can see (there aren't many), export to STL and you should be hot to trot, although I'd recommend using the netfabb cloud service to make sure.

Sorry if this is over-explaining it but it's difficult to pitch to the right level.

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Sounds alot easier in Blender IMO.

Select all faces, press Recalculate and presto, you're done.

Alright. I checked all the faces in SketchUp and reversed the ones that were backwards. I also tried Netfabb as per your suggestions. I'm going to post the revised model below and I'd appreciate any possible feedback before submitting it again to be printed. Thanks!

https://www.dropbox.com/s/nppc4sfxce...raft_fixed.stl

Love this board, tons of awesome people :)

My apologies, work has me busy :(

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Originally Posted by Eric052492

Alright. I checked all the faces in SketchUp and reversed the ones that were backwards. I also tried Netfabb as per your suggestions. I'm going to post the revised model below and I'd appreciate any possible feedback before submitting it again to be printed. Thanks!

https://www.dropbox.com/s/nppc4sfxce...raft_fixed.stl

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Your scale is off on that one, you will need to rescale it to 1.0 (or in Repg I think it's like scale x 1000%

Other than that, print away! your new slice looks much better

http://www.devogeninteractive.com/pi...F_5345F698&jpg

I agree! I am overwhelmed by the amount of responses I have received already! As for the scale being off on my model, I'm not sure why this happens. It seems any model I export from SketchUp to a .stl is always very small.

The oversize scaling seems to be a sketchup thing. I find that if I export the stl from sketchup, run through netfabb for repair and 're-export, then import the stl back into sketchup, it's hugely over scaled. So I work strictly one way...SU to netfab to slic3r.

Great tip on setting the contrasting face colours though...learn something new every day.

Cheers.

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Originally Posted by ShaneH

The oversize scaling seems to be a sketchup thing. I find that if I export the stl from sketchup, run through netfabb for repair and 're-export, then import the stl back into sketchup, it's hugely over scaled. So I work strictly one way...SU to netfab to slic3r.

Great tip on setting the contrasting face colours though...learn something new every day.

Cheers.

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I find just importing the STL into blender and making sure your Metrics are setup before you export also solves this issue.

There are a few encounters in the sketch information that need treating - they're inner rather than exterior. The standard plan creates it a little challenging to choose them out, but you can modify the configurations to create it easer.