Somewhat new to media blasting, question about throughput

[Justin8888]

I make small delrin parts (2"x3") that I blast with glass abrasive then bead to a matte finish. Im currently working with the smallest cabinet that redline makes. It pulls like 5cfm through I believe a 4mm fixed nozzle.

The problem is, the process is really slow, and I have a lot of parts to blast. I bought a cheap vib tumbler from HF thinking I would give that a shot and see if I can replicate the finish (will be here this week), but Im not confident that it will work.

I have only worked with this tiny blast cabinet. My question is, If I upgrade to a larger cabinet with a 7mm nozzle, that pulls 10-15cfm, would I see a massive increase in throughput? To put in simple terms, how im imagining it, could I basically just sweep the blast gun 1-2 passes along each side and be done? Right now, I blasting in basically 0.5-1" strips which takes forever even on small parts.

The upgrade would be costly as I would have to upgrade my compressor as well, so I would probably just deal with what I have if I wouldnt see a marked decrease in the time per part.

Just looking for general answers here from guys who have moved from a small cabinet to a large.

 

[senlow]

It's all about the amount of media volume that you can move. If you want to blast more efficiently, you need to move more volume of media. In most cases this means that you need to move a greater volume of air - cfm is King.

I have minimal experience media blasting plastics. But, it seems to me that glass beads would not be best for the application. You may want to experiment with different medias to optimize your results.

Vibratory tumbling may be a good alternative. It may take longer, but it will work while you are doing something else. The HF tumbler is awfully small for the size of parts you are working with. It may work, but a larger tumbler will work better. You may want to look into subbing out the tumbling operation. Many manufacturers and machine shops that have tumblers have extra capacity. The place where I work has two tumblers. One works about 15 hours per week, and the other hasn't run for more than 40 hours in the last year.

 

[LXCam]

Like he said ^^^. You need air, lots of air. The cabinet and nozzle is the simple part. Now you could consider just adding capacity too. Even a small pump will fill a couple of vessels. If you could get your hands on a couple tanks and plumb them in that would help. It would just take a while to fill.

 

[astroracer]

I just picked up another pressure blaster at a swap meet. This one:
http://www.northerntool.com/shop/tools/product_7959_7959
For 85 bucks...
I am going to see if I can adapt it to my blasting cabinet. Has anyone done this? Sure would make for a killer set-up.
Mark

 

[Justin8888]

It's all about the amount of media volume that you can move. If you want to blast more efficiently, you need to move more volume of media. In most cases this means that you need to move a greater volume of air - cfm is King.

I have minimal experience media blasting plastics. But, it seems to me that glass beads would not be best for the application. You may want to experiment with different medias to optimize your results.

Vibratory tumbling may be a good alternative. It may take longer, but it will work while you are doing something else. The HF tumbler is awfully small for the size of parts you are working with. It may work, but a larger tumbler will work better. You may want to look into subbing out the tumbling operation. Many manufacturers and machine shops that have tumblers have extra capacity. The place where I work has two tumblers. One works about 15 hours per week, and the other hasn't run for more than 40 hours in the last year.

Thanks

Yea I already know the HF tumbler is too small, I figured it was a cheap way to test the finish. If it works well, I'll either upgrade or outsource.

It looks like plastic abrasive media (pyramids/cones) might work well. Most people have the same reaction when I tell them I bead blast plastic, but you can actually get a pretty amazing finish on it. I start with 150 grit glass abrasive and move down to 220 bead, then wash and do a light coat of vegetable oil and it yields a really nice feeling surface finish. It's just so labor intensive