Need Tumbler help

[KeithSS]

Hi,

I have been making hooks ,and it takes as long to wire wheel them and wax them as it does to forge them. So

I made this 5 gal.bucket as my tumbler.  My question is now, how do I use it?

What type of media should I use to descale?

Should the bucket be 1/2 full or 3/4 full of media?

Also, should I put some thin cuts in the bucket to let the dust out?

 Thanks for any help you can give me.

Keith

 

[Alan Evans]

I used to pickle in Phosphoric acid which speeded up the wire bushing time but then you had to make sure the alkaline and rinse was dried out. But I did try other systems for the same reason as you.

I have only ever used wet tumbling or rumbling systems. Certainly I would be looking to contain any dust rather than releasing it to your lungs.

I made a plastic pot tumbler when I was silver smithing and jewellery making and that is similar-ish to yours. The axis was tilted off vertical rather than horizontal like yours though. I mounted that on an old record player turntable which was tilted at about 33˚ and rotated at 33rpm! It was also about 33% full. The media I used was snippets of silver and a splash of washing up liquid in tap water.

If you have got enough odds and sods of steel offcuts I would just use those.

Probably the simplest tumbler for metal finishing is a concrete mixer. Horribly noisy unless you can rubber line it...the best I could do was spray the out side with motor car stone chip stuff...slightly rubbery with a smooth dimpled surface which helped soften the rattle no end.

I did have a commercial rumbler at one time which was a huge rubber lined pig trough on springs with an eccentric weight on the attached electric motor shaft. The whole thing weighed almost two tonnes. I used granite chippings and stainless and mild steel scrap again with water and detergent. I did eventually try the proper (commercial) ceramic media and tumbling soaps. They did not make the metal look any better, but the granite chippings broke down and formed a slurry quite quickly.

The efficiency of the process depends on the tumbling action of the media and workpieces obviously. You might find that your horizontally mounted unit will rotate with the media just sitting in the bottom and not tumbling...it is why concrete mixers have fins inside and why the commercial brass finishing tumblers were wooden octagonal vessels. Before you put in ribs try tilting it at various angles to see at what point friction takes over from gravity. 

One other advantage to tilting it off vertical is that the lid is then just needed to prevent splashes rather than being under pressure all the time, and you do have the option to look in while it is rotating and add or remove stuff with ease.

Horizontally it is going to be a bit difficult to load. The big horizontal hexagon drum version I got part way through making had an access hatch on one of the sides...I gave up when I could not get the drive slow enough and bought the rumbler.

I should add that having gone through all the experimentation I found that the wet tumbling was a pain...you had to rinse off any media gunk and with mild steel dry it effectively before waxing...almost as labour intensive.

My preferred finishing system for domestic steel work is now shot blast with Chilled Steel Grit or Aluminium Oxide, rotary wire brushing/burnishing and Renaissance wax.

Alan

[Kozzy]

What A. Evans said about sliding is a large concern.  It is important to make sure the speed and % loading are adequate to keep the mix tumbling and not sliding or you woll not only develop flat spots but wear out the bucket quickly.  Getting the right speed can be tough with a very slippery container and you might need enough to almost throw the product up the sides to roll it.  Same problem occurs in rock polishing tumblers which is why it's recommend to never run a load less than "full":  Small loads tend to slide.

As to the media, it is going to be a balance between descaling and taking a little too much off.  In my vibrator, I use both a very coarse stone that looks exactly like a Hershey's kiss chocolate and ceramic triangles, depending on what I am trying to do.  In general, even with the heavier abrasive quality of the "kisses", I have found that part wear is minimal and edges still stay reasonably square.

In terms of shot media, what you want are called "ballcones".  The shape of those has one pointed end and a ring which concentrates the concussion over a smaller area and can better break scale free.  They also reach better into corners and small places than just round shot.  Kind of expensive, though.

[Glenn]

I have used a 55 gallon drum in the horizontal position with 3 each 2x4s placed equidistant on the inside to keep things stirred up and not sliding. Media was 1-2 inch nails, small metal scraps, etc. Lots of noise and not much dust as there was little rust on the metal.

A blacksmith from Texas suggested that I add some course sand and some boiled linseed oil to the mix to both reduce any dust, give a finer surface, and give the metal a slight oil finish. Worked very well here. RPM was just enough to keep everything stirred up and the variable was the time in the tumbler for the type of finished desired.

There was a tumbler on loan for a while that was hexagon in shape, welded up and heavy beyond belief. Horizontal in layout, pulley driven from a motor. It worked well but angle iron was added to stir the mix and keep it from sliding. Heavy beast but got the job done. Tumblers are also a good way to check your welds on the projects, and your ability to undo any tumbler puzzles as the projects can become interlocked. Many of my projects from that time period had a *hammered and oil finish* to the metal (grin)

There was one blacksmith that used a truck tire as a tumbler. Metal parts and media on the inside.

Like many projects, it is not how the project is made, or used, but the end results that actually matters.

 

[KeithSS]

Just read the replies, thanks. 

After getting a vibrator, and buying different media I wasn't satisfied. So built the 5 gal.bucket tumbler. I did put in two 1by2 boards to drop the media when it reaches the top. i don't  think I have enough media in it. I will try some nails that I have . The ballcones sure are pricy.  The noise is really loud. I only run it at night because I don't want to hear all day.  These tumblers have to be set up just right from what your saying.

I bought this disk for my 4 1/2" grinder and it is taking the scale off very fast and it looks like it was just lightly sanded. It is a woven material so it should be used with a mask. Until I get the tumbler stars all aligned . I'm gonna just use this disk and a slow wire wheel.

Yep, it doesn't matter how good of work you do, if you don't Finnish it nicely.

Type 27 Grinding Wheel, 4 1/2, 7/8 NORTON Zoro #: G4415381

 

[John Ditt]

Since I have been away from IForgeIron, this is a late reply. My prototype tumbler is large, quiet, low cost and easy to build.

First step is to pickle for 12 to 24 hours in food grade citric acid and neutralize in baking soda solution. The tumbling serves to remove the dust that the scale has become from the pickling. 

The cylindrical interior of the 55 gallon barrel and its two ends are lined with a rubber mat.

For now, I have used 'drainage rock' from Lowe's for the media. It's a fair action on removing the scale dust.

IMG_0068_2.m4v

This photo shows the interior.