How much material does an edge grinder remove?

[Dave Marshak]

I sharpen my edges maybe 20 or 30 times a year with a Swix Evo Pro edge grinder and I became curious about how many times I could grind before I went through the edge. I relaized I could measure the depth of cut with a test indicator on this jig I made several years ago to measure spoke tension in bicycle wheels:

First, I ground the edge to 88d with the medium wheel, then I ground a 40mm length of the edge 10 times with the medium wheel, and another section with the fine wheel:

. The depth of the fine cut was .002:

The medium was more than .003, almost double:

I made several measurements and they were all mostly consistent, with a few outliers due to operator error. It looks like the fine wheel takes about 0.0002 with each pass, the medium a little less than 0.0004. A new edge is about .06 inches wide, so I should be able to grind it 300 times with the fine stone, or 150 times with the medium. Based on that. I'm gonna mostly use the fine wheel every 2 or 3 days, and the medium only when the edges get too dull or when I expect very hard conditions.

dm

 

[Jacques]

Is that a base in the second photo?

 

[oldschoolskier]

Good idea, but without seeing your contact points both for measurement and grinding (I'm guessing), though I suspect you are giving yourself a poor test and inaccurate result. Short grind length and reference point of the same edge is the cause.

For a better result, grind the entire length and measure edge to edge at one point. I suspect your answer will bigger.

 

[James]

Is that a base in the second photo?

Yes. Painful to look at. Presumably it’s a trashed ski.

 

[Dave Marshak]

Good idea, but without seeing your contact points both for measurement and grinding (I'm guessing), though I suspect you are giving yourself a poor test and inaccurate result. Short grind length and reference point of the same edge is the cause.

For a better result, grind the entire length and measure edge to edge at one point. I suspect your answer will bigger.

I have no way to measure across the full width of the ski. My method is accurate enough to assure me I can grind as often as I want.

dm

 

[Dave Marshak]

Presumably it’s a trashed ski.

It’s a future Adirondack chair.

dm

 

[crgildart]

Be it a file or a grinder, any time you change the angle you are going to grind down metal thinner than it was before Edges used to be thicker..Just don't be this guy..

 

[SlideWright]

I sharpen my edges maybe 20 or 30 times a year with a Swix Evo Pro edge grinder and I became curious about how many times I could grind before I went through the edge. I realized I could measure the depth of cut with a test indicator on this jig I made several years ago to measure spoke tension in bicycle wheels:


I made several measurements and they were all mostly consistent, with a few outliers due to operator error. It looks like the fine wheel takes about 0.0002 with each pass, the medium a little less than 0.0004. A new edge is about .06 inches wide, so I should be able to grind it 300 times with the fine stone, or 150 times with the medium. Based on that. I'm gonna mostly use the fine wheel every 2 or 3 days, and the medium only when the edges get too dull or when I expect very hard conditions.

dm

Interesting. This sheds light on what I've been wondering with these tuners. How long will the stones last?

 

[Dwight]

I sharpen my edges maybe 20 or 30 times a year with a Swix Evo Pro edge grinder and I became curious about how many times I could grind before I went through the edge. I relaized I could measure the depth of cut with a test indicator on this jig I made several years ago to measure spoke tension in bicycle wheels:


View attachment 229468


First, I ground the edge to 88d with the medium wheel, then I ground a 40mm length of the edge 10 times with the medium wheel, and another section with the fine wheel:

View attachment 229476


. The depth of the fine cut was .002:

View attachment 229477

The medium was more than .003, almost double:

View attachment 229478

I made several measurements and they were all mostly consistent, with a few outliers due to operator error. It looks like the fine wheel takes about 0.0002 with each pass, the medium a little less than 0.0004. A new edge is about .06 inches wide, so I should be able to grind it 300 times with the fine stone, or 150 times with the medium. Based on that. I'm gonna mostly use the fine wheel every 2 or 3 days, and the medium only when the edges get too dull or when I expect very hard conditions.

dm

Pretty neat testing.

So is it .002 or .0002? Either one is good.

 

[oldschoolskier]

I have no way to measure across the full width of the ski. My method is accurate enough to assure me I can grind as often as I want.

dm

Don't measure the full length, grind the full length, measure the same spot left edge to right edge, this gives you the change in width or simply translated the amount of material removed, better measurable results grind both sides and measure as it doubles the measurement size making it easier to see.

I would mark with a scribe in the edge to get the closest identical location(s) for measurements even a few "thou" difference will effect the results.

I feel since you got the tools what you're doing is important to confirm actual cut amounts.

PM me privately and we can talk to setup the best easiest test.

 

[Sibhusky]

Pretty neat testing.

So is it .002 or .0002? Either one is good.

I thought he made ten passes mentioned in some post so I think that's how we changed decimal places.

 

[Tom K.]

My method is accurate enough to assure me I can grind as often as I want.

Yup, I think you've shown that clearly. Thanks!

No need to drill any deeper on this topic.

Or grind any further.

 

[KingGrump]

Interesting. This sheds light on what I've been wondering with these tuners. How long will the stones last?

I bought my Razor-Tune in Nov 2017. Used mostly the medium wheel. Used the coarse wheel to reset angle only. Probably do about a hundred grinds per season for friends and family.

The original medium wheel is still holding up fine. Minimal wear exhibited so far. I do have a new medium wheel as back up.

 

[SlideWright]

Thanks. Any idea on the Swix Evo/Toko Edge Tuner WC cutting wheels lifespan as a comparison?

 

[Dave Marshak]

Thanks. Any idea on the Swix Evo/Toko Edge Tuner WC cutting wheels lifespan as a comparison?

I have no idea. I bought an second fine stone after the first one worked down about half after about 20 grinds, or maybe a lot fewer. I never counted and I haven't been careful about which stone I use or how often,

dm

 

[Dave Marshak]

Pretty neat testing.

So is it .002 or .0002? Either one is good.

THe cut was 0.002 deep, but it was 10 passes so each pass was 0.0002. I should have made that more clear.

dm

 

[Tom K.]

THe cut was 0.002 deep, but it was 10 passes so each pass was 0.0002. I should have made that more clear.

dm

jayne nothin from nothin clip - Google Search

Damn you @KingGrump, there goes my tool budget!

Question: Does using the Razor Tune or Swix version also take care of the sidewall interference issue all in one step? I know how to plane a sidewall, but, for me, it's another annoying step that sometimes means I put off tuning for longer than I should.

 

[Schussboelie]

IIRC I saw in one of the Toko promo clips that sidewall planing is still required.
Which also makes sense, the sidewall dust would fill up the grinding stone in a heartbeat.

 

[KingGrump]

Question: Does using the Razor Tune or Swix version also take care of the sidewall interference issue all in one step? I know how to plane a sidewall, but, for me, it's another annoying step that sometimes means I put off tuning for longer than I should.

Usually I will rip the side wall with a cutter at the start of the season. Detail that out with a panzer in a 7° guide. Paying attention especially to the tips and tails. The panzer works better with the tight metal sandwiches at those locations.

For the rest of the season, I'll make couple quick passes with the panzer in a 7° guide prior to using the grinder and file. Not much of a hassle at all.

 

[Dave Marshak]

Question: Does using the Razor Tune or Swix version also take care of the sidewall interference issue all in one step? I know how to plane a sidewall, but, for me, it's another annoying step that sometimes means I put off tuning for longer than I should.

A high side wall will stop an EVO in its tracks. An RT has a heavier wheel that might power through but it’s still a good idea to scrape the side wall back. Plastic in an abrasive is never good and it might prevent an accurate cut.

dm