Large chunk of model not showing up when uploaded on Shapeways

After finishing up modelling and tweaking one of my mech designs, I uploaded onto here. To my surprise, I noticed a large chunk of my mech missing (detailed in the picture below).

I honestly do not know why this happens; my Sketchup model (pictured below) seems to be fine along with the .stl file. The mesh/model is watertight and seems to be fine as well.

This isn't the first time this has happened to me as it has happened before with my past models.
I'm extremely frustrated as I had to remodel many of my designs to make it printable, only to find out another piece, such as a wing, leg, etc, is now missing. It's come to the point of trial and error as I've spent countless hours removing this piece and adding another piece in hopes of retaining my original design and in hopes that the entire model is 'picked up' by Shapeways.

I don't know if it's something on my end or Shapeway's. Nonetheless, this is severely hindering my progress as I can use my time to create and upload new models instead of spending hours tweaking an existing in hopes that it won't get screwed up.

I've attached images to detail my predicament.

At this point I would like some light to be shed on this matter and answers as to why this is happening. Any help would be greatly appreciated.


A large chunk missing as denoted by the red circle.



The model as is in Sketchup.



The .stl as is in Accutrans 3D.

How are you checking the model to see if it's manifold? From your Sketchup screenshot, it looks like the model isn't manifold. In the attached image, I drew arrows pointing to intersecting planes that do not have 'hard' edges - this is a sure sign of a non-manifold Sketchup model.

I have never needed Accutrans for Sketchup models - just a combination of Solid Inspector to check for manifold issues, and the STL exporter to convert for 3D printing. Do you have those plugins?

If you want, PM me your model and I'll take a look at it.

Thank you for your response!

I took your advice and installed Solid Inspector. It works wonders! I was able to fix a lot of things.
I usually used Accutrans to check an object's manifold. Apparently it wasn't enough.

As for plugins, I already had the STL exporter. I installed Solid Inspector as you advised and it's wonderful. I foresee myself using it a lot!

I sent you a PM regarding a smaller problem with my model with its Sketchup file.

Again, thanks for your response!

Awesome! Glad that worked I got your PM, replying here for the benefit of others.

For cleaning up stray lines, get the Cleanup plugin - its amazingly fast. You can also use the eraser tool for cleaning up single lines.

Modeling as separate components like you did is a good practice because it allows for easier editing of the different parts of the model. Do you know about the Outer Shell tool to combine all the parts just before exporting?

I already had the Cleanup plugin like you mentioned; however I never ticked in the box for the 'clean up stray lines' portion. Well, now I do and it works like a charm!

As for the Outer Shell tool, I didn't know about that in fact. After finding it (under Tools for anyone curious) and using it, it made everything so much easier. I can now stop using Explode to have all the pieces become one giant one.

As of now my Mech is complete with a few needed tweaks, thanks to your help! I appreciated a lot!
I just realized how much I've learned from a couple of posts regarding how to make Sketchup models more suited and more efficient for 3D printing, all thanks to you!