Stumped on a part of the Cyborg Beast hand.

I am actually trying to help a little girl with a new prosthetic, I have done a practice run of the robohand and that turned out fine, now I'm starting the cyborg beast project.
However the palm design only has one tiny part of the thumb bracket that touches the bed and 99.9% of the part just hovers in the air. (see the picture) No good angle to lay it flat.
Working with slic3r if I try to enforce support for the first X layers, nothing happens. Ive tried 10,30,50 nothing. Ive tried full support which of course fills all the holes and just overkills it all around.

I had slightly better luck with cura but it still has it's issues as well with missing a couple key parts and leaving the bottom looking like a saggy mess.

My question is either how to enforce support for the first layers in slic3r? I don't understand why it wont let me. I have tried different setting profiles with the same result.
Or how to force it to lay flat and just cut off that little part of the bracket holding it up? Sketchup won't let me import it either to just try to edit it out so I am open to other options...


This one is confusing me.

 

I don't have my printer yet, so I can't help with the slic3r question but I can provide some alternative solutions...

Do you have access to modeling software? I'm no doctor, but I don't see why the thumb part has to be offset and not in plane with everything else. You could just move it back to be level with the palm.

If I'm totally wrong, you could just try modeling in some "pegs/columns" under the palm for support. I assume you will be using a stronger filament that could then bridge between the columns. You'd then have to sand the columns off.

 

You could try to place small flat peaces (other models) just below the area that hangs to act as support (just make sure the gap is smaller then you layer tolerance.) I have never tried anything like that so not sure how it would work...

Looks like it would be easiest to edit the model. Why wont sketch up load it? Do you need a converter or is it too big?

 

I would love to just sheer it flat but I guess I'm not sure how to do it. sketchup seems to import some STL files and not others for me. This is one of the no-go cases.

 

Try converting it to another format and back to stl then try to import it.

 

Or better yet... Try editing the g-code. Copy the first part of the code (the start up parts where it defines all the coordinates) and then find out what layer on which everything becomes flat remove the code before it and stitch it back to the start up code. Your printer will start out printing in the air but then you can pause it and manually lower your extruder via turning the z axis rods by hand.

I had a few prints fail due to filament stripping and software crashes so I had to use this method to restart them where they left off. You can use the g-code editor to find out what layer where everything gets flat by looking at your model layer by layer.

Sounds kind of complex but I cant think of anything in Repetier host that edits the model.

 

Interesting trick with the gcode and I will definately keep that in mind, Thanks.
Printed Solid actually pointed out to me that in Cura's advance settings there is a "cutoff object bottom" setting that is used for situations just like this. It litterally lowers the object down flat however mm or .mm you enter. Perfect.
Thank you you guys!!

 

Thanks again guys. This is a half scale test print in low quality but the beauty for me is it printed with ZERO support, raft or brim, so good test. I only had to drop it down in cura 1.2mm. Made it a world of difference. The finished one will be cleaner with support and finer layers. But Success!!