Hand to Hand Combat with Support Material

Prologue

My blog has been largely 3D Printing for over two years now and for the past months it has been 3D Printing as pertains to tanks.  My primary interest is in the 3D Printing but tanks are a fun proxy for more boring calibration prints!  Much if not all of what I write, however, should be applicable to printing in general...it does not have to be for tanks.

Introduction

So what about support material?   There are some models that absolutely require it and tanks are one of those things.  When I started printing tanks it was on a Makerbot clone and I was printing in ABS.  Once I got my Ultimaker I started to print in PLA and that is where some frustration started to manifest itself.   PLA supports are more challenging to remove than ABS supports...at least with the default settings in Simplify3D.   I presume that this is because of their different thermal properties.  Hot PLA laying down on top of warm PLA causes more fusing than the same thing happening with ABS...?

Battles with ABS and the Ultimaker

In any case I decided that the solution was to print ABS on my Ultimaker 2.  How hard can it be?  Well I have spent a lot of time trying, to the extent of even designing a special cooling system, and I just can not get as good a result with ABS as I can with PLA.  Don't get me wrong, the Ultimaker 2 can print really nice models in ABS, just not at the high resolution and high detail level that I want for tanks!

Simple Solution

I am not sure why it took me so long to figure this out...but...default settings are not always the way to go!  I use Simplify3D as my slicer and while there are a number of things about it that drive me mad it is a good product with one of its strengths being support material.  So I happily accepted default settings.  Not optimum!  So here are the changes that I made:

Default Settings

My Settings

Note that the above profile is for a 100 micron resolution print so adjustments might be different for other resolutions.  First, infill percentage for the support material from 30% to 12%. Second, an additional layer of separation top and bottom.  Third, inflation distance from 0 to as much as a millimeter.  This extra distance takes time to print but makes it easier to pull the support material off the model.  Another note...I will assume that you are already printing at the lowest possible temperature at which that you can till extrude?!?!

High Tech (and Expensive) Frosting on the Cake

The above makes for PLA prints that can be cleaned up pretty easily.  Much improved over the previous state.  So what could be even better?  How about a specialty filament that is supposed to combine the best aspects of both PLA and ABS but without some of the downsides of either?

Enter a reel of Colorfabb Ngen which is "produced with with Amphora™ AM3300 polymer and uses specific colorFabb developed color concentrates for good opaque quality and highest possible brightness. Eastman Amphora™ AM3300 3D polymer is a low-odor, styrene-free material uniquely suited for 3D printing enthusiasts, particularly those who need the flexibility to print within a wide processing temperature range."

It better be good as it costs 40 euros for a 750g reel!   That is twice what I am paying for an already upgraded filament.  While I am not prepared to comment yet on its performance other than for support removal...it is brilliant in that ball park!  It pulls off the model easily and leaves little if any scarring.  I am really impressed.  It is still work to remove the support but the product is really sharp.

Tools Needed for Support Removal

Here are my essential tools for support removal.  Small pair of pliers.  In the case of this pair I have actually used a dremel to file down the pointed end so it is even more narrow!   Xacto knife with a new blade being a help.  Some dentist tools.  Not sure what they are really called but that is what they remind me of.  Some files and sandpaper are good for final detailing but the below is what is needed to get the major cleanup done.

Adjusting Support Placement

Last but not least there are a couple things to be aware of when running your slicer.  Below is a screenshot from Cura.  Note the fill amount...that is where I got the idea to lower the S3D default. "Distance Z" is what I mentioned and what I used was two layers so it would be 0.2.   The other adjustment on this form is the "Overhang Angle" which can be adjusted if parts of your tank are not being supported when they should be.  Use the layers view as you change this value.

If you have sprung for a copy of Simplify3D then I would always check support layout using the manual support tool.  There are many vehicles that can benefit from some manual placement or from changing the support resolution setting.  Here is an example:

As Generated

With a Manual Support Added