sand blasting 3d Prints

Those California Air Tools compressors are great and really quiet - but sand blasting with one is asking a lot of it! My blasting cabinet keeps my 5HP 3PH  screw compressor pretty busy....

I ran one of those CAT compressors into the ground. It was running about 50% duty cycle for about a month in a peculiar application. I had talked to them about this and they said, well, maybe, try it, they are normally good for about 3000 hours in light duty cycle use. Eventually a downstream hose blew and it ran for several days non-stop, then started making funny noises (that's when it was noticed). CAT sent me replacement seals and cylinders free under warrantee even after I had explained what I did to it. One of the teflon piston seals was melted. It takes about 20 minutes to rebuild the whole thing, now it runs like new again.

Hi Julia,

You're correct if you don't provide the sufficient CFM for the sand blaster you will not have enough volume of air to push out the media and your results will most likely be poor or clog the nozzle. The noise is what kills me as well with the big air compressors that push out that amount of volume of air. Unless you use a rotary screw compressor but those are very very pricey.

Thanks, Antony. I have a big piston-type compressor from Sears that's not too loud to use occasionally in the office, but it does take up valuable space so I took it home last year when the air cylinder-actuated project I was working on ended. I can't stand the noise of big diaphragm compressors.

Hello Julia,

I hope you do not find my repeated questioning annoying, but since I am trying to decide for myself if the sandblasting option is worth high investment, you are my only hope for enlightenment. 

May I ask how you are doing with your sandblaster? Would you recommend it? Do you have any new pictures you might share? I would be especially interested in how the blaster is able to remove the lines and create a homogeneous surface. Do you think that small features like e.g. 1,2 mm thick window frames would be able to withstand the sandblasting?

thank you for your feedback

best regards

Andreas 

Hi Andreas,

I know you're anxious for an update from Julia but from someone who has done this with a less abrasive blaster (soda blaster) and have seen results of full on sand blasting it's not quite going to be as nice as you may think but it does blend the layers a bit better by adding a softer edge between each ridge of the layer but you have to take in mind layers have very small gaps and sand blasting is not going to remove just the high spots of the ridge it's going to remove everything all at once but it does blend them together softer and gives you a generally nicer appearance . If you want great professional results you can't beat sanding and filler primer followed by more sanding. 

Here's a follow who tried sand blasting on vapor bath parts to get a matte finish

http://www.soliforum.com/topic/448/diy-smoothing-station-ii/

Thanks techbuilder, I have been doing the paint and sanding thing on different models, for some it works OK but often I have to deal with engraved structures in surfaces, very delicate structures like window frames or small cavities like rooms enclosed by walls wich are very hard or even impossible to sand (and of course very, very time consuming. …).

So I had( and still have at least a little) the hope that sand blasting could be the magic bulle, but maybe you are right and it is not as great as I initially thought. …

Best

Andreas

Thanks techbuilder, I have been doing the paint and sanding thing on different models, for some it works OK but often I have to deal with engraved structures in surfaces, very delicate structures like window frames or small cavities like rooms enclosed by walls wich are very hard or even impossible to sand (and of course very, very time consuming. ..).

So I had( and still have at least a little) the hope that sand blasting could be the magic bulle, but maybe you are right and it is not as great as I initially thought. …

Best

Andreas

It may work out for you or at least reduce sanding time but it's not quite magic yet. Do you have a powder coating place near by you? You could ask them if they could sand blast that part for you as an experiment and they might do it for free or a small amount

I've tried sandblasting once:

[url=https://flic.kr/p/sfmkSP]17227676015_d34dd36cf8_z.jpg[/url]

not too bad but nothing you cant do with sandpaper.

Kleiner Tipp am Rande: "Spirtzspachtel" (gibts auch bei Obi)

@techbuilder:you’re right, think I will try to find someone around here to try a few typical pieces.

@ Eed: Danke für den Tipp ☺…

Andreas, sorry for the late reply and lack of info. I have not had time or the pressing need to haul my big compressor to the shop to pursue this further (new technologies and machines are on an as-needed-only basis for me :) ).

I am too lazy to use sandpaper to get into every nook and cranny of a detailed model, and it's probably not even possible with some prints - that was my motivation in getting the setup. Since it's basically the same principle as sandpaper, I expect it to work as well, but perhaps faster and with less effort and with a greater variety of available media. I'm sure others are correct about it not being a magic bullet for total removal of layer lines, but it can certainly be used after fillers, just like sandpaper, but again with perhaps less effort and a greater ability to get into small spaces.

In addition to smoothing, sandblasting also results in a very matte finish which is attractive/desirable in some situations.

Thanks Julia,

I will wait patiently😊

Best

Andreas

Hello during another search for this topic yesterday, I found an interesting company who sells special cabinets and blasting units, sounds very promising…

http://www.logiblast.at/

Stratasys recommends plastic blast media over sand.

"An ideal PMB is Polyplus, which has a Mohs hardness of 3.5 and a 20/30 U.S. standard sieve size (0.84/0.58 mm)"

What type of sandblasting media do you use