Home Brewed vibratory finisher

[JavaDog]

Wow! That came out looking great! Once you get it all dialed in, looks like you will have yourself a nice little machine there!

[Zipdrive]

That is really cool!!. So, if I understand correctly, the aluminum weights are drilled eccentrically and cause the vibartion, yes? How much weight did you use and what are the off sets? Are you going to change the weights and experiment more?

cheers.

[Mcgyver]

Fellow I met a long time ago had a de-burring tumbler he made by turning an old farm tractor tire inside out, running it on two rollers one being powered up from a small electric motor. Took up very little shop space as it is verticle, cost next to nothing to make and last a life time. Be sure to use tractor tires with directional tread, not turf savers or backhoe.

holy crap - turning a tractor tire inside out! does he rip phone books in half to!

the idea got me seaching and i found this http://www.acc.umu.se/~widmark/bigtumbler.pdf
but its more of a tumbler i'd guess than a vibration action.

nice job Unibiker. even with the springs it still walks all over? hmm, still, wouldn't mind making a mini version for the home shop.

SC thanks for the info, are all vibratory polishers used with a slurry or are some dry?

[sc7500]

[QUOTE=SC thanks for the info, are all vibratory polishers used with a slurry or are some dry?[/QUOTE]

Hey there. You are most certainly welcome - I'll help if I can !

Interesting question Re: wet Vs Dry ~ Sorta depends on the materials being deburred / burnished, and the end result required.

Everyone here has likely seen a cartridge case polisher used by home reloarders, yes ? That system uses materials like dry ceramic bead, ground corn cob and even crumbled cork to shine up spent carts... the guys who advertise microfinishing and "ultrapolish" services for trannie gears and such are using a dry ultrafine abrasive with a "burnisher carrier" like corncob or cork too...

The nice thing about using a wet media with soap for polishing is the carry off effect - especially with aluminum. As the surface burnishes, it is continually washed by the soapy polishing media. End result ? A mirror finish on everything from 3003 to 6061 T6.

Something I forgot to mention earlier; cleaning the polishing media. Now that everyone is gonna go and build one of these noismakers, better remember that it will need celaning eventually.

The best system we found for ceramic bead cleaning was a combination of water, laundry detergent [dry OR liquid, any brand you can stand the smell of] and Cascade dish washing soap.

I learned this method by trial and error, but it really keeps the bead surfaces ready for action... AND removes any oils or grease residue that might kill the soaping action and dull the surface !

Hope this help, y'all

Best
SC

[mpictor]

To guide the barrel, have you considered using parallel linkage rather than something for it to hit against?

I suspect that the barrel is losing contact with the springs when it is up as high as it can go... this will increase vibration and noise. Increasing the weight in the barrel would help, or use springs that are longer or less stiff.

I agree that it would be good to run a bolt or wire through the springs. If nothing else, this will contain the pieces if the spring snaps. Ever been around a large spring that broke? You don't want to be!

And one last item. I assume that the barrel is constrained so it can go up and down only - Have you considered shaking the barrel horizontally instead of vertically? I wonder if that would work better.

You have a great looking piece of equipment there. Hope it helps cut your time down.

Mark

[ckrantz]

I'm very impressed by the way this came out.. I was wondering if there was any advantage to vibratory polishing/deburring than tumbling. Its my understanding that tumbling takes a little longer than vibratory polishing.. About how much did you invest into your project?

[foxbay3]

A welder that had welded some large parts for me claimed that he had used a cement mixer with some alterations to deburr small parts of steel and aluminum. I think he said he used a differant media, but I'm not sure.

Good Luck to all...

[Unabiker]

I was able to spend a little time on the project yesterday.
Welded some feet to the frame and installed some concrete anchors. That made a big diff. At least I can run it without chasing it around the shop.

Bolting it down helped with the noise. It's still louder than my air compressor, though. Improving the guides should help with this. I'm pretty sure most of the racket is coming from the cradle whacking the guides from the side. I get about 1/4" of up and down movement when it's running. The springs have about 3/4" of preload. Losing contact with the springs at the top of the stroke doesn't appear to be an issue.

Using not much water mixed with some Simple Green, I was getting a reasonable finish in about 30 minutes. Still not quite there yet, though. I need to slow the action down a bit. My parts tend to "float" to the top of the media instead of staying down inside it. I think getting some more media will help this as well. Gotta get some of the liquid burnishiung compound too. I don'l like the crud that the Simple Green/water mix leaves on the parts.

There were a couple reasons I went the vibratory route instead of the tumbler route. The biggest reason being cycle time. I don't think it is unreasonable to eventualy get my cycle time down to 15-20 minutes. From what I've read, getting the same finish on the same parts would require several hours in a tumbler. I was also worried about my parts bonking into each other and causing unwanted marks with a tumbler.

At this stage, I've got well under $500 in the project....not counting time. There is about $100 worth of steel. 50lbs of media was $135. The 4 pillow block bearings were about $50. Springs and misc. nuts and bolts were another $50. The barrel was free. The motor was scavanged from my bone pile. I spent 4.99 on a Harbor Freight pump that doesn't work. I figure I've got another $50 worth of stuff to get the sprayer system sorted out. Probably going to spend another $300-$400 on a big-ass load of media here soon too. I imagine there is another $50 worth of foam insulation and lumber to make a sound-resistant booth to go around it.

Time wise, I have been working on this project for about 2 months as time allows. If I were to guess, I'd say I've got about 40-50 hours in it. I haven't really been keeping track, as this project has been a bit of play time for me.

All in all, it is a very small price to pay to gain 20- 30 hours a week.

[l u k e]

You did a great job on the fabrication and a great design. I've designed a few but never got around to making one. I guess I was hoping some parts would drop in my lap so I would have to buy them.

Just a thought, you might consider mounting your weights to the ends of the shaft. A simple plate with a slot across the middle would allow you to adjust the offset to control the vibration. It would be an easy way to tune the machine without having to make new weights.

[lerman]

As I understand it, the eccentric weights causes the whole thing to shake.

Why can't the motor drive an eccentric connected to the barrel to cause it to move directly? What am I missing?

Ken

[Kool Parts]

Actually you want the parts to go top to bottom. In a rotating fashion. You have a big tub, you will need (want) a lot of media. Here are a couple of places that I have got media and compounds from in the past. Very knowledgeable in all aspects of mass finishing.
Gary

http://www.vibratoryfinishing.com/

http://www.candmtopline.com/frames.html

[Unabiker]

Thanks for the sources of media. I'll give both places a call Monday.

I ran it a bit more yesterday. Definately need more media. It does have a nice top to bottom circulation going on. With this amount of media, it takes about a minute to turn completely over in the tub.

The finish isn't quite there yet. It's alright after 30 minutes. 2 or 3 swipes with a scotch brite pad cleans it up. I think with a bit more aggressive media and the propper compound, I'll be there.

I let all the water that had previuosly been in the tub drain into a bucket overnight. From 2 gallons of water, I got about a 1/4" of aluminum clay in the bottom of the bucket. I dumped the water into a large tub and put a fan in front of it to see how long it would take to evaporate.

This has me thinking that I will incorporate a setteling tank and filter into the sprayer system. I'm thinking that I'll park the pump up high in a 5 gallon bucket so that the crud can accumulate at the bottom. If I lined the bucket with a plastic bag, I could just let the goo build up to a certain point. Once it was "full", I could dump the water into the shaker tub with the drain closed and just change out the bag.

Ken,
You are correct in that the weights cause the whole thing to shake. The were a couple reasons why I chose not to just mount a weight on the motor. From the outset, I figured that different materials may need different frequencies to be adequately finished. This would mean that I needed an easy way of changing the speed that the weights spin. Using different sized pulleys to vary the alxe rpms seemed like the easiest, and most economical route.
The other reason is that I did not want to have all that weight swinging directly on the motor's shaft. The amount of force necessary to lift 300lbs of media and 100 pounds of frame, tub and parts 1000 times a minute would probably make short work of the bearings inside of a 25year old air compressor motor. With the setup I'm using, the force of the swinging weights goes through 4 1" ball bearings mounted in pillow blocks, which are all bolted to the cradle assembly. The motor still gets some side loads from the frame hopping up and down, varying the tension on the belt. But those loads are much less in size and harshness than they would be swinging the weight on the motor.


I considered the weights on the end of the axle shaft, but I am worried about something coming loose and ricochetting around the shop. My "weights" are 2 6" lengths of 3.5" aluminum tube, with a 1/2" wall. The axle goes through the tubes, and the tubes are bolted to the axle. If the weight mounting bolts were to break, the weight would just spin on the alxe. They would have to go through one of the bearing assemblies or the .5" wall tubing would have to come apart for anything to fly off of the axle. The largest piece that could come off the assembly is a bolt head.

To add weight, I figure I could use stick-on lead wheel weights. To remove weight, I will have to take them off and run them through the band saw.