[bob1112]

We are really trying to answer this question for our small production Al parts. We need to bring them off the VMC and hopefully run through a couple stages of tumbling to acheive a nice polish or near polish. Are the cam type box shakers better or faster or are the bowl types better? I think the bowls are quieter but what about the job they do?

Brandon

[Crash]

I like the bowl type better. We use rotating barrels and a vibratory bowl type. For a nice polished surface on aluminum, you will need to rough and finish tumble it. We use a plastic type of media for the rough tumbling. It leaves a soft, matte surface. It's a good surface to anodize. For a bright polished finish, ball burnishing is the best. We send a number of parts out for this process. There are some hard, ceramic media types that will put a nice finish on aluminum, but not as good as ball burnishing does. It approaches a hand buffed finish.

Good luck

[bob1112]

When you say ball burnishing, what type of ball are you talking about? The stainless balls? what size? Can walnut shell do it but take longer? I know the ball media is expensive so I would need to be sure of my purchase for sure. Thanks for the reply.

[Kevin Taylor]

Tub type I use work's great Noise is an issue but if it dosen't make noise it isn't going to doo anything for you plastic media leaves a good finish but if you have rough cut's ceramic first then fowellowed with plastic might be more to your licking Good Luck Kevin

[Crash]

Ball burnishing media is a small very hard, steel media. It lasts almost forever, but is very heavy. That's why we send our products out for this process. You would need a heavy duty machine for ball burnishing. You would also need to have a machine with a continuous flow of fresh soap and water to keep the parts clean. I think a vibratory bowl type would be best for this.

http://www.vibratoryfinishing.com/media.htm

[KOS]

for my anodizing I use a vibratory tumbler with the 1/4" plastic triangles to remove machine marks (i use the green ones), it will leave a matte finish. From here I then run it in walnut shells with rouge for about 36 hours. It brings the part to a very high shine. Since I want my anodized parts to look almost translucent I need to have a high polish before they go into the tanks...

[Stepper Monkey]

The plastic media is good, but for ball burnishing to a mirror polish shine I use ceramic balls. They have to be run wet (water with a couple drops of a special soaplike solution) to keep the black crap from clogging up thier microsurfaces but they work like nothing else.
I like the bowl systems for the pyramid plastic and the ceramic cutting media, as it is much fatser than tumbling. However, the ceramic balls are the opposite. I run three bowls in a row with descending order of cutting grits, followed by a rotary tumbler with the ceramic balls for a final mirror shine.

Only two caveats; The balls need to be broken in first - easy to do, just run them with some scrap for an afternoon. Second, the surface needs to be pretty smooth before the balls will shine them up - the balls don't actually remove much material, they just remove the matte finish, so make sure they are well vibro'ed down to a fine grit cutting media first.

[KOS]

hey stepper do the ceramic ball get in small areas? how big are they? The reason I go with the walnut shells is that they get in every nook and cranny.

thanks!

[Stepper Monkey]

The balls are 2mm for the smallest, so nearly everywhere anyway. They do like to get in every little slot and invariably on every piece a few want to stay wedged in a narrow slit or hole, so a dental pick to knock them out is always by the tumbler! Don't know if wlnut shell does the same.

[mxtras]

Can we get some folks to post some pics of the before/after, please? .

Include info on what media and what type of equipment and maybe some pics of the equipment and media, too.

Thanks!

Scott

[KOS]

they can get stuck in some very tight spots, just depending on how tight the area is...usually they dont get stuck at all...here is a sample shot no the best pick but you will get a good idea of what it can do.

please note that the middle pic says bead blasting although this one was put through the tumbler with the 1/4" green pyramids...

[KOS]

Hey Scott
Sorry I will have to take some pics of my set up and media for you, I only have an old shot of that part to post for now.... that is done with the set up i mentioned before...

[mxtras]

I would like to see the set up. Thanks for posting the pic.

Is there a way to get into this kind of set up on the cheap? Did you build or buy?

Scott

[KOS]

well I think it is a fairly reasonable price to get one set up... here is a link to the tumbler I have
http://www.eastwoodco.com/jump.jsp?i...emType=PRODUCT
here is the media I use, 1/4" green pyramids and walnut shell WITH rouge..
http://www.shorinternational.com/TumblingMedia.htm

I think most vibratory tumblers will work it will just depend on the size that you need for your parts....harbor frieght also sells an inexpensive one too, but I would reccomend getting the largest your budget can afford as you will enjoy throwing anything in there to get it cleaned up. Recently I took off the heat shields on my spark plugs for my car and polished them up too...

[mxtras]

I am interested for the same reason this thread was started - to debur smallish parts from a milling operation. More interest for deburring than for polishing or surface finish.

Would you suggest the vibrating bowl or a tumbler for deburing operations?

Scott

[KOS]

well some people say small parts and mean much larger stuff than what I make...so I just wanted to make sure...

I have both a rotary tumbler and a vibratory one. I dont like the rotarty one for multiple parts as the parts tend to bang into each other causing marks. The vibratory one just slowly moves them around in a circle. Although I will run both at the same time if I need the extra space, or sometimes on the rotatry if I am too lazy to change out the media and clean it out.

My personal preference is the vibratory over all...that may be though that I have just been more successful using it compared to the rotary. You can pick up are real cheap rotary one from Harbor frieght and test it out as well. I plan on adding a larger tumbler as well in the near future and it will be a vibratory as well.

For deburring parts they will work like a dream and you could get away with either of them, when I have used the vibratory for deburing it only needs to sit in there for a coulple of hours...not like the polish I showed in the pics that is a much more lengthy process to get done...

So since I have good success with my vibratory as you can see from my pics my reccomendation is the vibratory one..

[mxtras]

well some people say small parts and mean much larger stuff than what I make...so I just wanted to make sure...

The parts I am discussing are made from 6061 aluminum and are:

1/2" wide by 1" long, 1/4" thick
3/4" wide by 4" long, 1/4" thick
2" wide by 4" long, 1/4" thick

I am looking to deburr and produce a somewhat uniform finish. They do not have any burrs - just sharp edges.

I have a few hundred of the smaller parts and am working to make a few hundred of the larger parts, too. At this time, I am pulling them from the machine, knocking the holding taps off on a belt sander and stock-piling the parts in hopes that I will either obtain a vibratory finisher (and all of the required knowledge) or hook up with someone that has the capacity that is close to me to save shipping costs. At this point, I will pay - at least until I get a set-up of my own. I will likely end up taking them to a local machine shop that used to make these parts for me.

Keep the info and the pics coming, please!

Scott

[KOS]

with that type of volume you will def need to look at that largest bowl possible your wallet can afford. Otherwise you will only be doing a handful at a time.

The other option is to build one yourself. I think if you look on the net you can find some plans, I remember coming across some plans before but decided to just purchase my set up.

Basically you just put a motor underneath the bowl, and attach an offset weight to the shaft of the motor. So when it spins it makes the motor wobble and with the bowl sitting on some springs you will acheive a vibration.

Or simply build a couple decent size ones and you should be able to knock off those burrs.

I would say I could help you out but it doesnt look like I am close enough to you based on your post above.

BTW those MX holders are pretty trick!

[Crash]

Some things to keep in mind about larger operations of this type ... You will be producing a waste stream, which will have to be dealt with somehow. It can't be dumped in the sewer system untreated. We have a large vibratory bowl plus two large banks of rotary barrel tumblers. All the waste water/metal sludge goes into an underground 1500 gallon 3 stage clarifier (replaced last year at a cost of 30K), then the outflow goes into the sanitary sewer system. I'm required to submit self monitoring reports twice yearly to the regulating agency. They can and do come out anytime they like to inspect and pull samples for their own lab. We have to watch the amount of chrome and nickel we get, because we tumble and deburr lots of 17-4 and other alloys. The tank has to be pumped every 2 years, at a cost of 6-10k. It's a hazardous waste. You might get away with doing it on a small scale for awhile, but even one small one will produce some amount of waste. Another consideration- the larger machine you get, the louder it is. Ours is about 6' across, maybe 3 or 4 cf capacity. It's uncomfortable to be in the same room with it. We have it out with the punch presses, in a separate room away from the main shop. If you are just polishing aluminum, and not removing much material, your waste problems will not be as bad.

Good luck

[KOS]

I have always wanted to try out a wet system, however I have only ever tried the dry ones. I have read the wet lasts longer than dry does. Not sure on the difference of finishes though