Sharpening, Oregon 410 - Getting to Proper Guide Depth?

[FlyFishn]

4 hours ago, Stere said:

A progressive raker gauge files rakers lower as, as the chain teeth wear back the rakers need to be lower apparently.

 

http://gepkolcsonzo.eu/wp-content/uploads/2012/01/complete-book.pdf

 

 

Explained here.

 

 

 

Excellent post. Thanks.

 

Though doable, this makes the task a lot more complicated on the numbers. That might also explain the low cutting on the last 2 chains, but again - I didn't put any science in to the guide depths before. I can tell you the one I didn't use measured .044" and one of the ones I did use (after using) measured .043" - that was the one of the two I ran that time that cut best, but not great.

 

That would seem to align with the progressive cutting you mention. However, without a way to measure it (is there a triangular formula of some kind that takes in to account the width of the distance between the cutter and guide?) it is a "cut to test then regrind" process - and somewhat defeats the purpose of shop sharpening.

[bmp01]

5 hours ago, Stubby said:

It does it automatically if you use the cheap pressed steel gauges as they sit on the top plate  of the cutter . As the cutter lowers as you sharpen back so does the gauge . Simples

Are you talking about one of these steel gauges Stubby ? Might as well try to get something useful out of this thread, clearly the other numbers are gibberish.

[Stubby]

4 minutes ago, bmp01 said:

Are you talking about one of these steel gauges Stubby ? Might as well try to get something useful out of this thread, clearly the other numbers are gibberish.

Not quite . The one I am on about has a step in it and is narrower and fits over the cutters .

[Stere]

I didn't think the oregon type one was as good the last one. It files raker at a more of a slope also than the oregon does

 

 

 

 

Edited January 5, 2022 by Stere

[Stubby]

3 minutes ago, Stere said:

I didn't think the oregon type one was as good the last one files raker at a more of a slope also.

 

 

 

 

Thats the one . The lower one in the pic . Don't do what some bloke did and file with it still on there ! Just use it to test how much ( ie 3 stroke or 4 strokes ) per raker then just file all the others with the same number of strokes . If you want to be persnickety you can put a radius on the leading edge but to honest its not  the exact science you are making it out to be .  I am like the others , every 3rd sharpen I might put 2 strokes over the rakers . You kinda get to know whats needed .

[Stere]

 

 

The angled rakers from using the prog raker gauge one did seem to made a noticable difference after previously just doing then more flat

 

Seemed to make it cut smoother & also and less grabby

 

Was skeptical before I tried it.

 

 

Could just do the same freehand though, but before I tried the gauge I  never thought to angle the rakers as  much...

 

 

 

 

[bmp01]

31 minutes ago, Stubby said:

Thats the one . The lower one in the pic . Don't do what some bloke did and file with it still on there ! Just use it to test how much ( ie 3 stroke or 4 strokes ) per raker then just file all the others with the same number of strokes . If you want to be persnickety you can put a radius on the leading edge but to honest its not  the exact science you are making it out to be .  I am like the others , every 3rd sharpen I might put 2 strokes over the rakers . You kinda get to know whats needed .

That's exactly what I do (and expect what 99% of folk who use a gauge / experience do)..... But that ain't the progressive gauge thingee that Stere is refering to: where the depth gauge is (progressively) reduced a lot further as the tooth length reduces. Well,  that's if I've understood Stere correctly ???

[Stere]

Quote

But that ain't the progressive gauge thingee that Stere is refering to: where the depth gauge is (progressively) reduced a lot further as the tooth length reduces. Well,  that's if I've understood Stere correctly ???

Yes thats right

 

 

[bmp01]

Thank you.  Got a couple of the progressive gauges a while back, I'll have to find time and a candidate chain (1/2 to 2/3 used) for a test.

 

[Dan Maynard]

A progressive raker gauge files rakers lower as, as the chain teeth wear back the rakers need to be lower apparently.
 
http://gepkolcsonzo.eu/wp-content/uploads/2012/01/complete-book.pdf
 
 
Explained here.
 

 
 

I'm still bothered by this.

If it's true that the depth gauge should be at 0.045 when the cutter is worn, then my chains which I file with a constant 0.025 should be cutting almost nothing. That is not my experience, they seem to cut just fine all the way to the end of the chain.

I also don't buy the argument about the contact point tipping over the back rivet, most of the force in the chain is tension and reaction force in the opposite direction to that from the cutters. The implication here is that the tooth will be rotating so that the raker lifts up off the bar, to reduce the cutter engagement. Can't see that happening.

Smells a bit of marketing and how things have always been done rather than proper explanation of forces and actions.