Chainsaw "Square ground cutter" sharpening?

[Bill]

Question: How do you properly sharpen a saw chain with a "square ground cutter"? (This is flat filed as opposed to round filed.)

The chain with these square ground cutters is Stihl RSLFK, RSLK, or RSLHK. (

)

Do you just use a flat file and free-hand (without any guide)?

I found some information on this at the Oregon saw-chain web site. It says; "Only use files specially designed for square-ground chisel cutters, available from your chainsaw dealer." [Double-Bevel, Hexagon, and "Goofy".] This was on the last page of the following link...

know where to buy these files online? Or which type of file is best to use?

Comments/Opinions on saw chain which is "square ground" -vs- "round ground"?

[Mike Marlow]

Just based on your questions, it appears you're not terribly experienced with chainsaws. If I've read too much into your questions then I guess you can ignore everything else I have to say and accept my apologies. If however, you are as unfamiliar with chainsaws as your questions make it appear, then my immediate advice is for you not to screw around with square ground cutters.

Sharpening any chain requires a certain amount of practice in order to get a good cutting profile. It's certainly more than just hitting the cutters a few licks to sharpen them up. It's not rocket science by any means, and anybody can certainly develop the skill to do it, but it does require an attention to what you're doing, and understanding of what you want to do and of course the most important part - a practice at achieving that desired goal. Square cutters are a lot harder to cut properly and offer nothing to the fellow who isn't cutting very large diameter trees with huge saws. You just can't get into wood cutting enough on a casual basis to warrant going to a square chain. They rely on a critical angle between the top of the cutter and the side and slight variations - which are easy to end up with, will really screw up the cut.

Do yourself a favor and just stay with the chain your saw came with.

[Harry K]

Don't bother unless you are a professional. I wound up with a square chisel chain by accident once. Loved the way it cut. Could not file it by hand, dealer had no way of sharpening it. We converted it to round file - just use a round file and the usual angles.

I hang out in a professional arborist/logging forum. Even the professionals have a very hard time learning to file square cutters. Angles, pressures etc. are critical.

Harry K

[Neon John]

Not quite answering your question directly, but you might want to take a look at the carbide tipped chain. I didn't realize they still made that chain. I used to use that type on a bow bar with an 80cc McCoulloch SuperPro when I was doing high volume firewood harvesting. The carbide chain takes a lot of horsepower but even with dirty trees and the occasional rock strike, stays sharp all season.

If I were doing any wood cutting at all nowadays, I'd have another bow bar:

one I use is somewhat wider and more squared off than this one.

The difference in fatigue at the end of the day after using a bow vs a regular bar is remarkable. When felling a tree with a bow, one stands behind and to the side of the tree and simply pushes the saw in. For delimbing and bucking, one can remain fully upright and let the weight of the saw do the work. And because the bar is so narrow, it rarely gets pinched and wedging is rarely necessary except when felling to direct the fall.

I see in googling that the usual panty-wetting types scream about safety. I can't see any difference. Any chainsaw is dangerous in the hands of an incompetent.

John

[Martin H. Eastburn]

Thanks for the site - haven't looked - but have now - have a 192-T Pico chain. Just found out tonight on the page - under the model page - there is a recall. Safety item. Really nice 6.6# saw for high and light work.

Have a 20" for the big stuff. :-) Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

Bill wrote:

[Bill]

The chain the saw came with *does* come (from Stihl) with square ground cutters. It is a Stihl "RSLFK" (full skip) chain for a Stihl MS-460 and a 32 inch bar. This chainsaw will *only* be used for bucking large diameter logs. (I have a smaller chainsaw with round filed cutters which I use for the smaller stuff.)

I do have experience with the round filed chains, but not with the square ground chains.

I have read on the internet that a square ground chain has a bit of additional cutting speed, and that is important to me as the logs I am cutting are quite large in diameter. So worth the investment in learning how to sharpen the chain for square ground if it is worth it - cutting speed wise.

Although the chain came with square ground cutters, I do have the option of filing them with a round file and no longer having square ground cutters.

I have a friend who has been a logger for 15 years and he says he prefers round filed, although other loggers prefer square ground he says.

I told him I wanted to try the square ground for awhile, then file them with a round file and see which I prefer. (And I should learn something in the process.)

Just wanted some additional feedback on which is better and tips on sharpening. Also where to get the special files online if possible.

[Stormin Mormon]

Years ago, I read about the difference between "chisel" and "chipper" and "Semichisel" chain.

Chisel had square teeth, and chipper had rounded corners on the teeth. From the end, chisel chain looked like a 7, and chipper chain teeth looked more like a ?.

The chisel chain was supposed to be faster cut.

[Bill]

The cutters on my chain look like "7's". Following are all the different variations of saw chain you can get from Stihl...

Pitch

1 = 1/4" 2 = .325" 3 = 3/8" 4 = .404" 6 = PICCO (3/8" Extended)

Gauge (on drive link)

1 = .043" (1.1 mm) 3 = .050" (1.3 mm) 5 = .058" (1.5 mm) 6 = .063" (1.6 mm) 0 = .080" (2.0 mm) (Harvester Chain Only)

Cutter Type P = PICCO R = RAPID

Cutter Shape C = Comfort (Low Vibe Version) D = Duro (Carbide Tip) DS= Duro Special (Carbide Tip) M = Micro (Semi-Chisel) S = Super (Full Chisel)

Special

1 = Triple-Humped Tie Strap 2 = Triple-Humped Tie Strap 3 = Single-Humped Drive Link F = Full Skip H = Semi Skip L = Square Ground K = Classic Cutter design N = Narrow S = Special

Number of Drive Links in Reels Type 100'

1/4" 2400 3/8" PMN 1640 3/8" P 1640 .325" 1840 3/8" 1640 .404" 1480

Various Stihl Cutter Types...

Saw Chain Identification...

[Bill]

Here are the different Oregon (brand) saw chains available...

Low-Kickback Chains...

.325" Pitch Chains... 3/8" Pitch Chains... .404" Pitch Chains... Kerf Chains... Chains...

[Harry K]

Go to arborist.lawnsite.com

That is a professional and semi professional forum although anyone is welcome. Search the "chainsaw" forum for filing info. You will find more than you really want but will find what you need. It will also give you on-line sources for chainsaws/tools/etc.

Baileys.com (I think that's right) is one off the top of my head.

Harry K

[Bill]

Q: Is a square ground chisel chain really better than a round ground chisel chain? A: Yes, if cutting performance and efficiency are what you are after. Square ground chisel chains perform 10% to 15% better. If maximum stay sharp ability and ease of filing are your objective, the answer is: no.

[Harry K]

Yeah, that's it. Sorry about that.

The Arborist site is one awesome resource. I hope you sign up and join in some of the discussions. Asbestos pants might be required in some of them. You would probably enjoy looking through some of the archives.

Harry K