Stonewash Media

flatgrinder

flatgrinder

Joined
Dec 20, 2005
Messages
2,045
Anyone know what would produce a "stonewash finish" (similar to CRK's Sebenza) in a vibratory machine?

Thanks! :thumbup:
 
im also interested in hearing about techniques for this finish... i have heard of guys actually putting knives in concrete mixers...
-Lou
 
vibe1.jpg


vibe2.jpg


vibe3.jpg
 
NATHAN, Great pictures and sure it works. Could you post any information on using this type of media. Type of equipment needed etc. Wet or dry? How big should it be do say 10 inch knives. You made me curious. I am sure the shape is a big key but, we have lots these ceramic beads and cylinders from catalyst (yes some were originally platinum coated)and I have been thinking for some time about tumbling or vibrating them. Jim
 
Also will the this take out grinding marks at all or do they still need to be completely gone first. Speak Nathan.
 
It is really difficult to take a picture of a steel finish, I guess in part because so much of your perception of a finish is how it looks as it is turned in different light and how it reflects. The stone wash finish is nothing like a bead blast finish, but it would be difficult to tell the difference looking at a pict. I mention this because going back and looking at the pict I took this morning, it is hard to read what it looks like.

Jim,

I know nothing about vibratory tumbler design. I do know the vibrations produce a swirling motion in the media, so the contents rotate probably 10 times a minute in addition to being shaken like mad. This tumbler has a very high amplitude vibration compared to a brass polisher, which would effect the type of finish you'd get (probably rougher). If the lid comes unclamped while it is running it makes an ungodly racket. As it is, I keep it in the back corner of a workshop in the back of my property nowhere near my shop or studio because of the racket and mess. It is 230 volt three phase and it shakes the mess out of stuff. (can be used to mix paint BTW)

I would guess a ten inch knife would fit in a 12" long, 8" dia cylinder and you could do five at a time. How to shake it? I don't know...

It is run wet for the same reason wet stones are run wet. I use old coolant from mill sump change outs. Contains a cutting aid and rust preventative, but rust preventive detergents work too.

I run a bolt through a hole in the tang to prevent them from sticking together.

I would not recommend tumbling stainless behind carbon steel.

Nathan
 
Bruce Bump said:
Also will the this take out grinding marks at all or do they still need to be completely gone first. Speak Nathan.
Click to expand...


It will take them out completely unless they are deep. These were taken to 400 grit and the grind marks are gone after tumbling over night. I will actually put the grind marks back after HT, but I'll use a scotchbrite belt.
 
My last post makes no sense out of context, why tumble the grind marks out just to put them back on?

These blades are from my WIP last week. I'm tumbling them to deburr them because they're fresh off the mill. The tumbling leaves a fine edge break and brings out the engraved sig. I'll leave the tumbled finish on the flats (grind marks still visible too) and put a scotchbrite finish on the bevels. It is a cool appearance I've done before. It gives it some contrasting texture, but it is still fairly bright, which helps D2's corrosion resistance.
 
This blade was hand rubbed to 400 grit before I tumbled it. This after 20 minutes in my tumbler. I'm still playing.

Bladetumbled-2.jpg
 
Thanks for the information. I have plenty of projects going right now but, it does interest me. I can see how it could be a good tool to have around even if around is the far far corner. LOL
 
Thanks Nathan,
I dont mind spending the hundred bucks for the ceramic. I wonder if it will work dry in one of those old rock tumblers you see at yard sales sometimes. I kinda like the look. Even an elcheapo mortor mixer may do the job.
 
I can tell you that crushed rock does not work.

BB's mixed with abrasive powder does not work.

Sand does not work.

Anything you can think of, that doesn't cost $100, does not work.

This is a heavy aluminum oxide (still a ceramic I guess). I also use a light ceramic cylinder that is much less aggressive. After HT, the effects are much less aggressive too. Then there is loaded polymer or loaded walnut shell. Taken in that order, and given a few days you can achieve a mirror polish. A mold maker I know uses this approach to polish molds such as tail light reflectors which are hard to polish by hand. I tend to stay away from mirror polishes because they accentuate my sins. If I were Bruce Bump, a holy pious grinding machine who commits not grinding sins, I would use this approach for mirror finishing if I had a bunch of blades to do. Which I think he does...

Media should be cleaned after use. The process generates "mud".

The process releases toxic metals locked up in some alloys, such as the lead found in a lot of brass, or beryllium in some hard copper alloys. I always treat the mud and dust with some respect.
 
Good post - I was gonna ask the same thing.

Nathan
So the pointy points are small enough to penetrate your signature too ?

Is your tumbler a commercial model? if so what?

Could you take some pics of the mechanism?
to give me an ideas of the range and direction of motion...

I think the type of vibe movement is directly related to the finish and just a rotary drum tumbler would give a different result ???

Is the bucket of the tumbler round bottomed?
I get the impression that it is a rectangular tray

http://www.kramerindustriesonline.com/vibratory-finishing-systems.htm
 
Last edited:
Steven Penner said:
Good post - I was gonna ask the same thing.

Nathan
So the pointy points are small enough to penetrate your signature too ?

Is your tumbler a commercial model? if so what?

Could you take some pics of the mechanism?
to give me an ideas of the range and direction of motion...

I think the type of vibe movement is directly related to the finish and just a rotary drum tumbler would give a different result ???

Is the bucket of the tumbler round bottomed?
I get the impression that it is a rectangular tray

http://www.kramerindustriesonline.com/vibratory-finishing-systems.htm
Click to expand...



Sorry to be slow getting back to you. Today is HT day, keeps me hopping...

"Nathan
So the pointy points are small enough to penetrate your signature too ?
"

No, the points are not able to reach into the bottom of the engraving. But the sharp edge of the engraving gets smoothed out and rounded and reflects highlights, which makes it stand out better. Also, some polishing mechanism may be taking place from the slurry, because the heat colors in the bottom of the sig are removed after HT. Here is a pict from a previous batch:

21.jpg


"Is your tumbler a commercial model? if so what?"

Yes it is a small commercial model, Boniardi. It is a two chamber design, which I like because I can run one media or set of parts in one chamber, while another set in the other. I got it used on Ebay many years ago. It wasn't expensive. Some larger units have mechanisms for separating small parts from the media and for continuous water flush.

"Could you take some pics of the mechanism?
to give me an ideas of the range and direction of motion..."

All of this is inside the unit. The range of motion is probably 1/16". I don't know what the direction of motion is.

"I think the type of vibe movement is directly related to the finish and just a rotary drum tumbler would give a different result ???"

I suspect that is probably true.

"Is the bucket of the tumbler round bottomed?
I get the impression that it is a rectangular tray"

Yes, it is round bottomed an about 7" deep.
 
Thanks for all the replies! :thumbup:

Nathan, Bobby: what grit do you use? On something like hardened D2, I'd expect it to be pretty rough? 50 or 80 grit media?

By the way, do you really run it overnight? -Seems like a long time, but if it works, it works! :)
 
flatgrinder said:
Thanks for all the replies! :thumbup:

Nathan, Bobby: what grit do you use? On something like hardened D2, I'd expect it to be pretty rough? 50 or 80 grit media?

By the way, do you really run it overnight? -Seems like a long time, but if it works, it works! :)
Click to expand...



It isn't a particular grit that I know of. I'm sure it is something, but it isn't given.

The effect of stuff like this is very non-linear. Yeah, I ran it over night, but it probably didn't look much different in the morning than it did at five hours. A couple hours usually does the trick.
 
Man i love that signature, gotta put CNC on the shoppin list :)


Raytech
3/8 “ ceramic Polyhedron
Order # 41328
20 pounds is $100

www.mscdirect.com
MSC order number
09117508
 
Last edited:
I experimented with tumbling blades to get that "stonewashed" satin finish. Like Nathan I got ceramic media from a lapidary supply store. The ceramic that I purchased had no abrasives in it. I got no better results using abrasive powder. Wet definately works better than dry, I used simple green straight out of the bottle. Just enough to keep things wet. My problem is that I was using my reloading tumbler, it is round, so I could only fit shorty blades like a paring, or bird and trout to get effective results. Too big would not tumble freely. I will post a pic later when I get home.

I plan on purchasing one if these and modding it. I do not have all the logistics figured out yet but before teh end of the year I will have one in the garage for surgery. Rotary tumbling is the ticket for doing big blades, as large vibratory tumblers for big stuff are crazy expensive.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=2528
 
You must log in or register to reply here.
Back
Top