Any experiences with glass bead or plastic bead blasting of PLA?

[foehnsturm 970]

I'm tempted to try as almost all other post-processing possibilities for PLA show considerable disadvantages (already tried THF, Ethyl acetate, vibratory tumbling, surface remelting, ...). Not looking for the time consuming hand polishing approach. On their website, Stratasys claims "bead blasting with plastic media is an ideal solution"

[neotko 1,417]

I only have experience with sodablasting. My next test (when I get time) will be using Garnet. I have plans to test this in a month or so but to buy it you need to get it in packs of 25kilos. I will try garnet because it's quite soft and it doesn't kill the user (like sand can). And it last 5-7 cicles. My compresor its a bit short but it works.

I also tryed the rotator can thingy to polish prints, but it takes way too much time and it's way too noisy.

Btw if you plan to polish a lot of pieces, or big stuff, you might need a 800€ (Big horse power) compresor plus the cabinet, air pistol, cables, etc.

I got a 100€ cabinet really nice and a 200€ low noise compresor + airblaster pistol and modded the nozzle and intake. It works, but for small objects (sodablasting basically removes the glow of pla and makes them matte).

Edited March 6, 2016 by Guest

[foehnsturm 970]

I might start with visiting a local blasting job shopper where you can do blasting by yourself as well. Do you think with the proper media it will even out the layering structure on the surface?

[neotko 1,417]

I suppose so. Specially if you have access to the good stuff (bigmama compressors). The only I would check it's if they have a very small nozzle airpistol, and you will need to play with the airpreassure because the faster it blows the more it erodes the print. My experience it's only with soda atm, but if you over do it you get uneven result, so you need to 'paint' the sand, and you need to get the hang of it to make it even. For soda even if you do it over and over there's no way to remove the layer lines, but one of the up sides it's that since it's air, you can't over heat it, if I get the nozzle too close it cold downs quite fast.

The only tests I found on internet about pla and sandblasting look nice, there's a guy that did some tests with pla and sand and seems ok. Anyhow I stay away from any sand, I don't like silicosis

So, yes give it a try! There's a lot of sanding materials! (but not many ecofriendly or health-risk-free).

[JohnFox 25]

I tried vibratory tumbling - too slow.

However I had great success with a similar method - centrifugal disk finishing. Similar to vibro finishing but a lot more energy goes into it and it is a lot faster, typically 45minutes for a smooth surface.

The machines are quite expensive, >£2000 for a starter machine.

[foehnsturm 970]

Ah yeah, saw this somewhere. Would certainly be tempting as a DIY project. But the material of the bowl and rotating disc could be a problem.

Did you use wet or dry polishing?

[JohnFox 25]

This was wet polishing on a machine similar to the one below:-

http://www.sharmic.co.uk/index.php?option=com_content&view=category&layout=blog&id=25&Itemid=45

I did try and build one from a polythene bucket and a plaster paddle, running off an electric drill.

http://www.powertoolsdirect.com/vitrex-mixing-paddle-65-x-410mm?utm_source=google&kwd=&utm_medium=merchant_pla&gclid=CjwKEAjwuPi3BRClk8TyyMLloxgSJAAC0XsjCQJ5KMY2kjIE-GRQC2vVg_KTET3JXJX6LCJ60Z1jORoC89nw_wcB

The drill was too fast, I needed something like a 300rpm motor.

 

Ah yeah, saw this somewhere. Would certainly be tempting as a DIY project. But the material of the bowl and rotating disc could be a problem.

Did you use wet or dry polishing?