Post Processing: Step 1 - Obtain Test Items

The more I research the various ways people are post-processng their 3D prints in ways other than vapor treating ABS, the more I realize that getting it right is going to take some serious repetition and experimentation.  After all, for the most part, we are using equipment and smoothing material that are designed for rocks and metal parts.  So, to some extent we are in uncharted territory.

So, I am going in three different directions... epoxy coating, rotary tumbling and vibratory tumbling.

Smooth-on XTC 3D Print Epoxy Coating

I've ordered the Smooth-on XTC.  It should arrive in a day or two.  The total cost, with shipping was around $38.00.  I also called Smooth-on to try to establish some contacts that could give me quick help if I run into difficulty.  I don't want to be unfair to a product due to my own inexperience.  I managed to get through to technical support right away which was encouraging.  So, it seems we are off to a good start with XTC.  But, I will need to purchase a better mask before working with it.

Smooth-on XTC 3D Print Coating

Harbor Freight Rotary Tumbler

If tumbling works, it's probably a good idea to purchase a more robust rotary tumbler.  But, for now, the Harbor Freight dual tumbler is on sale for under $55.  The double tumbler should allow me to test two different media at the same time for the same time, allowing for better comparison.

Harbor Freight Double Rotary Tumbler

Harbor Freight Vibratory Tumbler

Harbor Freight offers both a 5lb version and an 18lb version.  I have purchased the 5ib version at under $55.  Shapeways uses a professional vibratory tumbler for smoothing nylon parts.  While I'm not sure that trying to use a tiny tumbler will perform anywhere close to the monster they use, it was certainly worth exploring.

Harbor Freight Vibratory Tumbler

Starting Materials Selection

Since I'm starting this process from a completely ignorant position... my usual starting place for such adventures, I've simply picked up the most easily available materials for the first tests.

• Medium Ceramic Abrasive Polishing Tumbler Media

• Rust-Cutting Resin Abrasive Tumbler Media

• Rock Polishing Abrasive Set

• Ground Glass Abrasive

• Petco Mini White Aquarium Gravel

We'll discuss each material type as we test them. 

I will start the first preliminary tests today.  But, I don't expect to report anything until I know that I am using the right proportions for each tumbling method.  For instance, rotary tumbling usually involves water.  But, how much is not so easily determined by searching the web. The vibratory tumbler that I purchased is NOT intended for using with water.  But, is it still advisable to put the pieces into the tumbler in a wet state?  Again, it's not clear from the little research I have done.  So, I don't expect great results any time soon.  All we can promise is that we're going to give it a good try.

But, it would be VERY helpful if you have any experience at all to share it.  :) 

An Additional Test Item

I should also mention an additional product that I will be testing with Infinity Supports.  Frankly, I'm still not comfortable with washing off the supports directly in any of my sinks where chunks of support might be washed down the drain.  I am more comfortable with ensuring that the Infinity Supports have been thoroughly dissolved first,  I've been using a bucket for this purpose.

But, at the same time that I picked up the vibratory tumbler, I picked up a  portable parts washing station at Harbor freight.  

 It's not at all clear if this is a good solution or not.  But, at under $50, it is certainly worth exploring if it helps us avoid unintended and unexpected issues down the road..