Grinding Stihl RM chain

[Tommy Collins]

It seems that there is much confusion about setting the grinder angle for Stihl RM chain and many chains have been ruined.
First let me make this point...when file sharpening RS or RM chain, we use the same file, file guide and filing angles, therefore they are sharpened the same.
Here's the confusion...Stihl shows us the side plate angles, and on RS chain the side plate extends all the way up to the top corner of the cutter and is 60 degrees at that point and happens to be the angle that the grinder should be set.
But...on RM chain there is no corner and the rounded portion of the semi chisel cutter is not considered part of the side plate, therefore the top of the side plate is actually located further down in the rounded gullet.
Stihl states that if you use the correct diameter file, held at the proper depth and angle, the side plate angle, which I know of no way to check on RM cutter will automatically be correct.
The side plate angle shown by Stihl for an RM chain is NOT an angle setting for your grinder, it is useless information.
Set your grinder angle the same as you would for RS chain,use a properly shaped wheel of the correct thickness, grind to the proper depth and the side plate angle at the point where Stihl considers it to be, will automatically be correct.
Let me know if this clears up any confusion as it did for me
And also if you find fault with it.
Tom.

 

[ChoppyChoppy]

55* and 30* is what I grind pretty much all chainsaw chains at. Harvester chain I do 55* and 35*.

I run semi chisel on my main saw, I sharpen it the same as if it were full chisel.

We get just about every brand in the shop, those settings seem to work fine. Granted often get chains that are so dull they'd cut better if put on backward so I suppose any amount of being sharp is an improvement!

 

[HarleyT]

59.33 and 30.68 here.....

 

[HarleyT]

I consider the side of a grinder stone as the angle result. A file, being round, will leave a different angle, unless you do the work with your eyes open. Which is why declaring a certain diameter file is silly. Also one must keep the depth of the file in mind, as most folks tend to force the file downward.
One must watch the angles that he is creating, and know what angles he is going for.

A grinder is consistant, as the side of the wheel is the angle that will be left on the cutter.

 

[Stihl 041S]

59.33 and 30.68 here.....

Enabler.......

 

[HarleyT]

It's all in the wrist, baby.......

 

[Stihl 041S]

I consider the side of a grinder stone as the angle result. A file, being round, will leave a different angle, unless you do the work with your eyes open. Which is why declaring a certain diameter file is silly. Also one must keep the depth of the file in mind, as most folks tend to force the file downward.
One must watch the angles that he is creating, and know what angles he is going for.

A grinder is consistant, as the side of the wheel is the angle that will be left on the cutter.

And now you are bring a lot of facts into the discussion.

HAVE YOU NO SHAME???!!!!!!?????

 

[HarleyT]

I have been pulling to the right since puberty....

 

[Stihl 041S]

It's all in the wrist, baby.......

Can we get back to saws!!!

 

[Stihl 041S]

I have been pulling to the right since puberty....

I learned to read with one hand.

 

[HarleyT]

Had I had the internet, my early life would have been entirely different.....

I would have had little or no skin pigment, and would have a hell of a handshake....

 

[Stihl 041S]

Popeyes must of had the Internet.

 

[Tommy Collins]

Many of us use angles that suit us best.
The purpose of this post is to inform those ,like myself , who mistakingly assume that the side plate angle of 75-85 degrees, shown by Stihl ,for RM chain , is NOT intended to be used as a grinder setting and ,if used , will result in a cutter that is far too blunt and will bear no resemblance to a new cutter.
I am suggesting that they use the same grinder setting as for RS chain .
We are all free to modify our grinding angles as we see fit.
Bottom line is that the side plate angle shown by Stihl for RM chain is worse that useless, it's misleading and confusing and if you use it as a grinder setting, you will ruin your chain.

 

[Stihl 041S]

Many of us use angles that suit us best.
The purpose of this post is to inform those ,like myself , who mistakingly assume that the side plate angle of 75-85 degrees, shown by Stihl ,for RM chain , is NOT intended to be used as a grinder setting and ,if used , will result in a cutter that is far too blunt and will bear no resemblance to a new cutter.
I am suggesting that they use the same grinder setting as for RS chain .
We are all free to modify our grinding angles as we see fit.
Bottom line is that the side plate angle shown by Stihl for RM chain is worse that useless, it's misleading and confusing and if you use it as a grinder setting, you will ruin your chain.

Thanks. I would have tried to get those numbers.
. I just use 30-60 and then stick them in the dirt. Lol

 

[J.Walker]

For hand filing Stihl RM should it be filed from the inside out or outside in?

 

[lambs]

Thanks to the OP for pointing this out. I tend to use 58 / 30 / 0 on both RS and RM chain.

But I was never sure why Stihl decided we no longer needed to tilt the chain vise or add 10 degrees of up angle when filing by hand. It seems to not make much difference though, so I stopped doing it. I guess that may be the reason?

 

[Cody]

Thanks to the OP for pointing this out. I tend to use 58 / 30 / 0 on both RS and RM chain.

But I was never sure why Stihl decided we no longer needed to tilt the chain vise or add 10 degrees of up angle when filing by hand. It seems to not make much difference though, so I stopped doing it. I guess that may be the reason?

I file both at 30/60, but I still do the 10 degree tilt on chisel, I enjoy sharpening semi chisel more so maybe someday I'll stop tilting the base. As long as I can cut wood with a sharp chain, I'm happy, not going to complain about a few seconds here or there.

 

[Stihl 041S]

I file both at 30/60, but I still do the 10 degree tilt on chisel, I enjoy sharpening semi chisel more so maybe someday I'll stop tilting the base. As long as I can cut wood with a sharp chain, I'm happy, not going to complain about a few seconds here or there.

Exactly..........I use chipper chain in dirty wood so I can keep cutting.

 

[Tommy Collins]

For hand filing Stihl RM should it be filed from the inside out or outside in?

I read that Inside out was recommended and the file chatters less in that direction for me.

 

[lambs]

I think you're only supposed to file inside out on both the cutters and the depth gauges.

Of course most grinders cannot do that.