Tumbler Original Rolling Knife Sharpener review – Are diamonds a knife’s best friend?

REVIEW – The Tumbler Original Rolling Knife Sharpener is a safe and effective way to sharpen almost all knives, but does it grab your attention at its price point? I retained all 10 fingers during my testing and found the Tumbler easy to use and compact to store. Join us for a read and comment if you wish.

⬇︎ Jump to summary (pros/cons)
Price: $189.00
Where to buy: Tumbler

What is it?

The Tumbler Original Rolling Knife Sharpener is a cylindrical, diamond grit knife sharpener with a 20 and 15 degree edge guide and stropping bar.

What’s included?

• Tumbler sharpener
• Angle guide
• Leather stropping bar
• Instructions

Tech Specs

• D35 grit, diamond impregnated sharpening surface
• Stainless steel honing surface
• Suitable for all knives (except serrated)

Design and features

A quick search on Amazon revealed over 20 brands of sharpeners designed like the Tumbler. I won’t debate which came first, but it probably wasn’t Tumbler. I’m guessing the patent must have expired. But I’m here to review the Tumbler. I can say the system seems very well made, has a premium feel and works as advertised. Is it the best sharpening method ever? Well, I probably haven’t seen them all. It’s not the slowest way to sharpen, but it isn’t the fastest either, yet it works well.

To use the Tumbler sharpener, you choose a knife for sharpening, place it onto the magnetic edge guide at the 20 or 15 degree angle side, hold the edge guide steady, and roll the diamond grit side of the sharpener cylinder back and forth along the knife’s edge the same number of times on each side of the knife.

I had to make this video one-handed. The sharpening action should be along the entire edge surface all the way to the tip, and the angle guide should be held securely during sharpening. Or you could hold the knife handle during sharpening for extra safety.

You have to remove the knife and place it back on the edge guide to sharpen the alternate side of the blade. It probably seems obvious, but do the same number of sharpener swipes on both sides of the blade. I’d start with 20 swipes per side, then decrease to 15 each side, then 10, 5, then 3, 2, 1 each. Then I’d wipe off the blade with a damp cloth, use the stainless steel side of the cylinder to smooth the knife edge with several strokes per blade side, then make a few strokes on the strop bar. I’d next check to see if the knife edge still reflects dull dings and cuts the edge of paper. If necessary, I’d repeat the same procedure.

The strop bar is a wooden bar with a 5/16″ leather surface.

The blade should be swiped on the leather in the opposite direction you’d use for cutting, and at the same angle you used for sharpening. Stropping gives a final polish to the blade edge and helps even up the burr to a proper ‘straight up’ at the blade edge.

Assembly, Installation, Setup

I read the instructions completely and viewed the brief video the instructions recommended, because the Tumbler was a new sharpening method to me. It’s very simple. A caveman could do it. There’s nothing to set up beyond taking the sharpener, edge guide and stropping bar to where you want to sharpen your knives.

This is the proper knife position for sharpening. Note the back of the blade is resting on the table surface and the magnetic angle guide holds the knife in place.

Performance

The blades of our paring knives seem to get banged up between sharpenings, so much that I can look straight down on the knife’s edge with a bright light overhead and see edge flaws reflecting light.

A sharp knife edge should not reflect any light. Using the Tumbler on a knife in such a condition can take 10-15 minutes. If I service these knives more often it won’t take that long to refurbish the blades with the Tumbler.

I found that smaller kitchen and pocket knives slip down the magnetic edge guide holder during sharpening.

That got frustrating, so I’d just hold knives in my left hand at a 20-degree angle without using the edge guide and roll the Tumbler sharpener against the edge with my right hand. There would be no risk of accidental cuts as long as I grip the knife and sharpener firmly and be slow and deliberate with the motions. Maybe Tumbler could make a thinner edge guide for small knives, so the knife could rest on the counter or table during sharpening, as do larger knives.

The diamond grit retains some material from sharpening and it does not wipe off. Tumbler says this is normal. 

The formerly shiny, honing side of the sharpener began to show a cool design after sharpening 8-10 knives.  This too is normal and the honing worked well. 

Moderate pressure of the sharpener cylinder against the knife blade seemed to produce the best results. Too little pressure and you’d have to take longer on the process. Too much pressure would seem to be too aggressive to the knife’s edge.

Tumbler points out at their website product page that this system is not intended for serrated knives or scissors. One side of the blades of our serrated knives have a flat, non serrated side to their edge. I had success using the Tumbler at the 15 degree angle on that flat side of a couple of my serrated knives.

By brain-jury is out on the cost of the Tumbler system vs. how it performs. It really works but would I spend $190 on this particular sharpening system? And would you? The Original Tumbler without the stropping bar is $129 if you have an old belt around to use for stropping.

I find stone knife sharpening to be a slow process. The Tumbler was faster for sure.

Final thoughts

The Tumbler Original Rolling Knife Sharpener is an effective sharpening system for almost all knives, and is simple to use and store. If you like the price, it should give many years of service.

What I like about the Tumbler Original Rolling Knife Sharpener

• Simple to use and is a reliable sharpening method
• Sharpens faster than traditional stone sharpening
• Easy to store

What needs to be improved?

• Smaller knives slip down the edge guide during sharpening
• Seems expensive

Price: $189.00
Where to buy: Tumbler
Source: The sample of this product was provided for free by Tumbler and the company did not have a final say on the review and did not preview the review before it was published.

Check out these other reviews!

• TSPROF Kadet Expert+ Knife Sharpener Kit review
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