Restoring with a Tumbler

There are a number of ways to get a good finish on a restored blade. From hand sanding to buffing. Each has detractions and benefits. The use of a tumbler is a fantastic middle ground between cost and time and has a few benefits on top of that. Tumbling does not work well for removal of pitting, but is fantastic for cleaning and polishing. They are useful in that they require no personal time while they are working, take little space and are much cleaner to use. Tumblers are also your best option for keeping etching intact on a blade.

Best results come from razors that are sanded to about 600 grit before tumbling. Any rougher and you might have scratch patterns too deep to get polished.

Getting started

The Tumbler

There are two basic tumbler styles available; Vibratory Tumblers and Rotary Tumblers. As the names would imply Vibratory Tumblers essentially shake the tumbling media around in a bucket while Rotary Tumblers work more like a dryer and spin.

For our use a Vibratory Tumbler, such as you would use for cleaning brass to reload ammunition, is ideal. There are a number of manufacturers out there making good products. Midway is a good option and they stand behind their products. Additionally you can usually find tumblers at gun and hunting stores like Cabela's or Sportsman's Warehouse or likely at local gun stores.

Tumbling Media

There is still a bunch of experimentation going on with respect to media and the various results. For Starters though the two basics of Walnut (use first) and Corn Cob (for final polish) are fantastic. Harbor Freight carries small plastic pyramid tumbling media that works well for an initial clean up before the walnut and could be used in place of it with extra time in corn cob and leaves a very interesting satin finish that I can only describe as "starburst".

Additives

Metal polish will increase the effectiveness of your tumbler media. Good options include Turtle Wax Rubbing Compound, Blue Magic and other similar products. Liquid additives will load much easier than paste styles.

Other additives are limited only to imagination. Try using diamond paste (20 grit seems to be a great option for speeding up the initial cleaning stage and actually works well with blades sanded to lower grits) or Chromium Oxide powder (.5 microns in your final polish media for example).

The Process

Tumbling, while a great option for many reasons, is not a quick process. It will likely take a the majority of a week of tumbling in Walnut followed by Corn Cob medias to reach a clean mirror shine.

To Start you want to load your media into the tumbler bowl (follow the directions on your specific tumbler for the load amounts) and if you are using any additives mix them in. Run the tumbler free of razors to mix in your additives until the mix is clean and evenly dispersed.

Loading Blue magic polish into corn cob media

At this point you may start to add in your razors. People have had varying success with different amounts of razors in the tumbler at any given time. The consensus seems to be no more than 3 razors in a 5 pound tumbler. Too many razors and they tend to group up in the tumbler which does not allow for media flow-through and slows up the whole process. As a note it is a good idea to demagnetize any razors you hand sanded on a magnetic jig prior to tumbling as the slight charge can lead to grouping as well.It is best to remove the blade from the scales as they will limit movement and tend to clog up with media.

While you will likely be tempted to check more often you will probably want to keep constant tumbling in your first media for 48-72 hours. Once you reach a nice uniform finish you will want to switch out your media to the finer Corn Cob. Follow the same loading process and repeat tumbling until you get that mirror shine you are looking for.

You can keep your medias for re-use. A little more additive each time is advised , but your loading time will be much shorter generally. Multiple bowls for your tumbler are handy for keeping your medias ready to go.

Tips and Tricks

• Buy a spare tumbler bin. Swapping this media out is annoying.

• I loaded my media with Flitz. It's about the consistency of toothpaste, and after emptying the corncob I saw that two of the globs I dropped in (out of 5) had just stuck to the bottom of the tumbler. So for the walnut, which I also Flitz'd, I mixed the polish by hand into a bowl of some of the media so it wouldn't stick to the tumbler. This is only an issue with thicker polishes.

• A roughly 50/50 mixture of walnut and plastic pyramids with a bit of rubbing compound helps the pyramids move around and cuts down on the noise they create. I have been able to clear up 320 grit scratches quite well with this mixture.

Other Uses

• The tumbler is a versatile machine and uses are only limited to your time and creativity.

• You can add a nice polish to acrylic scales (possibly horn I need to test that though) or smooth out the final levels of your CA finish.

• The Tumbling process.
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  Razor before tumbling

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  Razor before tumbling

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  Let's get started

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  12 hours tumbling in walnut

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  24 hours tumbling in walnut

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  24 hours tumbling in walnut

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  36 hours tumbling in walnut

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  24 hours polishing in corn cob

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  24 hours polishing in corn cob