Chain angle of cut

[ditchrider]

I'm looking at the Timberline Sharpener to maintain my saw chain. Available sharpening angles are 25, 30 and 35 degrees. Does anyone have an answer, or opinion, as to what angle to grind and why? Thanks.

 

[MasterMech]

Most of the time your better off sticking with the OEM angle. 99% of the time that's 30 degrees. 25 will produce a more knife-like edge that wears (read:dulls) quicker and 35 will do the opposite, producing a thicker edge that wears slower but isn't as aggressive.

EDIT: Wow I must've been tired! I do have that last bit backwards!

I'm not an expert in ripping/milling chains but I believe most of them are using smaller angles to produce a better finish.

wkpoor might have some info as to how race chains are filed, that is if he's willing to share.

There is no definite "best" angle because it will depend on cutting conditions. If we're following the masses, they suggest 30 degrees works pretty well in most situations. In my opinion unless you are filing a race chain or have some other reason to deviate, follow what the chain mfg recommends. Dirty bark, wood species, moisture content, temperature, operator, etc all have a noticable effect on cutting performace/chain longevity.

 

[StihlHead]

Stihl recommends most chains be sharpened at 30 degrees. I think the above reply is inverted; 35 degrees is a sharper angle and cuts and dulls faster, 25 degrees is more blunt but stays sharper longer. The Stihl chains I use are factory ground to 35 degrees when new, and I file them to 30 with an Oregon bar mount hand file sharpening tool. I also use a zero offset (90 degree) on my chains. I have all 3/8 standard bars and chains on my large bar mount Stihl saws. I have picco 3/8 on my small (but very versitile) MS211 saw. I use both semi chisel and full chisel chains, full comp and full skip, and I file them all with a round file. I use full chisel in clean wood, semi chisel in dirty and cruddy wood. Full chisel is 10% faster cutting, but the chisel points dull faster, especially in grit and dirty wood. Full chisel square filed results in the sharpest and fastest cutting chains, but that is for racing or where you want about a 10% faster cutting chain than round filed full chisel chain.

 

[ditchrider]

use full chisel in clean wood, semi chisel in dirty and cruddy wood. Full chisel is 10% faster cutting, but the chisel points dull faster, especially in grit and dirty wood. Full chisel square filed results in the sharpest and fastest cutting chains, but that is for racing or where you want about a 10% faster cutting chain than round filed full chisel chain.

I never had good luck with the round chisel chains. The sharp didn't seem to last long and for some reason it's easy for me to get them out of balance. I've always had good maintenance life from the full chisel, even though as you say, most of my work is dirty work. The wood is normally okay, but I need to fell so close to the earth that there a guy really has to pay attention not to ding on a rock on the other side. And sometimes the trees grow around the rocks and you find one part way into the cut.
And maybe that would change once I get a timberline sharpener, taking the difference between left and right handed sharpening out of the picture. But I think I'll keep with the full chisel. Try to solve one problem at a time
I never liked my Husky 346 until I went to full chisel. OEM was the round one.

 

[smokinj]

cut them at 30 degrees 60 on the tilt now anything from 25-35 will work the closer you get to 35 the more aggressive it will be. If your saw has less horse power you want to be closer to the 25 degrees.

 

[wkpoor]

wkpoor might have some info as to how race chains are filed, that is if he's willing to share.

Race chains are square ground. Can be done by hand or with special grinder design for square grind. Silvey makes one. I use same angles as round ground for the most part but I'm sure that varies a little with different saw power levels. The biggest difference is how small the tooth is. A race chain tooth will only be a small triangle.Way past what you would consider totally wore out. Can only be used on soft woods. Like anything race its no good for anything but timed cuts in pine and aspen.
Race chain builders usually won't let other people see their work. A good chain might cost near a grand.
BTW square ground can be bought on the roll or any chisel tooth filled that way or vise versa. I have a roll of square. Nice smooth quick cut. If you don't want to resharpen the same they can be sharpened to round.
Here is a link for the nuts and bolts to square chain.
http://www.madsens1.com/bnc_chisel_qna.htm

 

[smokinj]

Real race chains are done with a goffy file....Not square ground. Not to metion the time it takes to do the ribets. (Proven race chain can cost you 1000's of dollar bills)

 

[wkpoor]

Real race chains are done with a goffy file....Not square ground. Not to metion the time it takes to do the ribets. (Proven race chain can cost you 1000's of dollar bills)

I use a square file for square chain but some use the goofy file. I had an Eric Copsey chain here for a few years and it was done with a square file. You can tell because the corner is nice and crisp. Here again not everyone does them exactly the same. I suspect no 2 race chains are alike. Only thing they share in common s the very small tooth.

 

[smokinj]

I use a square file for square chain but some use the goofy file. I had an Eric Copsey chain here for a few years and it was done with a square file. You can tell because the corner is nice and crisp. Here again not everyone does them exactly the same. I suspect no 2 race chains are alike. Only thing they share in common s the very small tooth.

Like I said a proven race chain is worth 1000's. Can be worth more than the saw its self. The rest is just a good work chain.

 

[wkpoor]

Like I said a proven race chain is worth 1000's. Can be worth more than the saw its self. The rest is just a good work chain.

I meant I had an Eric Copsey race chain, not work chain and it was square filed.

 

[DexterDay]

I'm looking at the Timberline Sharpener to maintain my saw chain. Available sharpening angles are 25, 30 and 35 degrees. Does anyone have an answer, or opinion, as to what angle to grind and why? Thanks.

For the $10 extra dollars. You get the 25° and 35°… So the Hearth Discount basically pays for them. Its only 2 extra pieces, but depending on the way you install them, dictates whether its a 25° or 35°…

I got them just to experiment. Not being great with a hand file, I will admit. So the Timberline is a life saver (chain saver).

Again, for the investment of over a $100, I would buy the extra angles. IMHO

 

[StihlHead]

I never had good luck with the round chisel chains. The sharp didn't seem to last long and for some reason it's easy for me to get them out of balance. I've always had good maintenance life from the full chisel, even though as you say, most of my work is dirty work. The wood is normally okay, but I need to fell so close to the earth that there a guy really has to pay attention not to ding on a rock on the other side. And sometimes the trees grow around the rocks and you find one part way into the cut.
And maybe that would change once I get a timberline sharpener, taking the difference between left and right handed sharpening out of the picture. But I think I'll keep with the full chisel. Try to solve one problem at a time
I never liked my Husky 346 until I went to full chisel. OEM was the round one.

Madsen's has a good essay on the difference in cutting of the different profile cutters, and all kinds of stuff on sharpening chains here:

http://www.madsens1.com/bnc_teeth_types.htm

I use Stihl RM semi chisel in the crud. Its non-safety semi-chisel and it stays sharp a lot longer than full chisel does in crappy cutting conditions and is far easier to re-sharpen than full chisel. I had a loop of square filed full chisel once and I cannot sharpen that stuff to save my life. If you rock a full chisel it really takes a lot of file them back. I started using semi chisel when I had some new RM2 loops (Stihl semi-chisel with the safety rakers) that came on some Stihl saws that I bought. I used them for stump cutting when I managed a 100+ acre tree stand in the central coast of Oregon. I found that they do not rock as easy and they lasted a lot longer in the woods and when cutting firewood from slash piles. RM is hard to find, and I only found it at one store in Cottage Grove. RM2 is not made by Stihl any more.

So if I am cutting clean wood, I use round filed full chisel RS or RSF (skip). If I am cutting in crud, I use semi chisel RM. If I am likely to rock a chain I use one of my near gone chains, or RM2 with the safety rakers.

 

[StihlHead]

From Madsen's:​

Our Advice​

1. If you are a professional timber faller working in the Pacific Northwest or Alaska, use square ground chisel chain.
2. If you use square ground chisel chain, buy a chisel grinder or become friends with someone who owns one. Filing square ground chisel chain is very difficult. Few people do it well. Of those who can file it, most would do an even better job if they had a grinder.
3. If you cut cedar, salvage, or work in dirty conditions, use round chain. It is easier to sharpen and will hold its edge better for you.
4. If you are working in clean wood and want the best cutting performance, but can't afford a square grinder, use round ground chisel chain. This chain performs well, is fairly easy to sharpen with a file, and will out-cut poorly filed square chisel chain every time.

 

[amateur cutter]

Round filed 3/8 full chisel here, except for the 192, it runs Picco. 30 degrees seems to be the "happy" medium for me. A C