# Ripping chain sharpening



## Pcbw69 (Feb 10, 2020)

Hi I have a woodland pro 42 inch ripping chain that needs sharpening. The bench grinder I have available doesn’t seem to tilt enough to get the angles I need, only goes up to 55 degrees. Am I looking at this wrong? PS, This will be my first time sharpening ANY chainsaw chain. Here is a pic of the box with the specs 
Mine is the 3/8 pitch 33rp

any help would be greatly appreciated


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## rarefish383 (Feb 10, 2020)

Welcome to the site. I use out of the box Stihl, yellow box, chain. I'm too lazy to swap chains back and forth between milling and cutting firewood. After others posted pics of slabs they milled with ripping chain, and my slabs were better, I never bothered trying it. Sorry I didn't answer your question. I hand file all of my chains. My biggest bar is 45" and I use full comp on all of them.


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## buzz sawyer (Feb 10, 2020)

I also use the same chain as firewood on my sp125c / 36". Finish is fine for me and it cuts well - about 5 mins on a 25" x 8' slab of Ash. Keep the chain tight and rpms up. I like to lead a little with the nose.


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## rarefish383 (Feb 10, 2020)

I'm with Buzz, but I'm jealous, I want an SP125. My biggest is a Homelite Super 1050.


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## Pcbw69 (Feb 10, 2020)

the ripping chain works beautifully when sharp but I hit a rock or nail that was embedded on my first pass and that pretty much ruined the day. After the second slab I had to put all of my body weight into the saw to make it through and kind of chewed it up. I’m just confused as to what I set the grinder angle at. The box says top plate cutting angle 60 degrees but is that the tilt of the blade or slide at the base. Also 80 degrees for the side plate angle?? 55 degrees is where the grinder maxes out in any direction. Just doesn’t seem right


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## jnance (Feb 10, 2020)

On my grinder tip the wheel/motor to 60* The vise turned to 10* then for the 80* my vise tips 10*. 


Sent from my iPad using Tapatalk.


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## Philbert (Feb 10, 2020)

Based on the angles printed on your box, for your chain:

The grinder head tilt should be set at 60°.

The grinder vise should be rotated to 10° Right and Left.

Set the depth gauges (after sharpening) to 0.022".

Use a 3/16" grinding wheel.

Some grinders do not adjust to theses angles, or have some angles fixed, or only accept one size wheel. What brand / model grinder are you using?

Philbert


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## Philbert (Feb 10, 2020)

Some general tips on using a grinder in this thread:
https://www.arboristsite.com/community/threads/511a-grinder-improvements-tweaks.197073/

- Take lots of small taps to avoid overheating the cutters.

- Dress the wheel frequently to expose fresh abrasive.

- Practice on some scrap chain first.

Philbert


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## Pcbw69 (Feb 11, 2020)

Thanks for the replies guys
I’m going to invest in an Oregon sharpener and give it a shot


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## Mad Professor (Feb 12, 2020)

I use a file.


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## BobL (Feb 13, 2020)

Philbert said:


> - Take lots of small taps to avoid overheating the cutters.
> - Dress the wheel frequently to expose fresh abrasive.
> - Practice on some scrap chain first.


Definitely agree with the last two, unsure about the first one.
Have chewed the fat over with a few guys about this many times

The theory is that on a chain the steel behind the hard chrome coating on a sharp cutter does virtually no cutting. 
The majority of the cutting is done by the hard chrome plate covering the cutter edges which is not affected by grinder heating and this also stays very hard even under red heat, a bit like like HSS
IN practice filing does not sharpen anything, all it does is remove enough supporting steel under the Cr to generate a new hard chrome edge.
When a saw goes blunt this means the chrome edges have started to peel off further exposing the raw cutter steel underneath, which rapidly rounds over and makes increasing amounts of what is called cutter edge "glint" , and of course much powder.
Efficient sharpening effectively removes just enough steel to remove the "cutter glint".
To maintain a "glint-less" cutter top and side plate requires frequent touch ups. 



Below shows an extreme example - it's a cutter from one of my full comp cross cutting chains after cutting a couple of hardwood slabs.
The what looks to be two top plate cutting angles is because this chain is mid conversion from 25º to 10º .
The lower part of the cutter edge with almost no glint has been filed several times at about 10º and the top part is the original angle that has been left at 25º 
Over successive sharpening the 10º segment gets longer while the 25º segment decreases in size until it disappears.
The 25º segment has severe "glint" because the chrome plate has been peeled right back exposing the cutter steel underneath.
The 10º segment has about the glint I expect after a cut or two in hardwoods I mill.

BTW This also suggests that converting a cross cutting chain in this way is not as efficient as converting it by degrees, ie 25 then 20 then 15 etc so that there is always no glint right across the cutter edge.
Talk about nerdy chain stuff eh! I better stop here. 




My mate who always uses a sharpener argues that overheating a cutter enables the Cr plating to peel off easier. Because I rarely use a sharpener I have not be able to assess his argument.


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## Bmac (Feb 13, 2020)

Awesome info and awesome post. I've often wondered the best way to convert a cross cutting chain into a ripping chain, I do it the way you are showing with the top plate slowly reshaping into a straight 10 degree edge. I've often wondered if this was the best way to convert a chain. How much do you think the unsharpened section on the top plate affects cutting efficiency?


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## Philbert (Feb 13, 2020)

BobL said:


> Definitely agree with the last two, unsure about the first one. . .
> The theory is that on a chain the steel behind the hard chrome coating on a sharp cutter does virtually no cutting.
> The majority of the cutting is done by the hard chrome plate covering the cutter edges which is not affected by grinder heating and this also stays very hard even under red heat, a bit like like HSS



A lot of stuff covered in your post Bob; as always I appreciate and respect the perspectives you bring. But I am sticking with '_avoid overheating the cutters_' as a general rule for grinding chains.

1. If you want to *intentionally* overheat and harden the cutting edges, for some reason, that might be something else. Certainly, the teeth on many inexpensive, hardware store saws are induction hardened (which makes them next-to-impossible to hand sharpen). And most laminated guide bars have induction hardened rails. But most chain manufacturers do not do this with their cutters. So, if you are over-heating and hardening cutter edges due to lack of skill or knowledge, that would be carelessness, not intent.

2. Cutter edges are very fine; a harder edge will be more brittle and more prone to chipping.

3. '_Grinder hardened_' edges are impossible to file, so not a good option if you file in the field and grind at home (like me), or if you are 'evening up' a chain for someone else who will be filing in-between machine sharpenings.

5. I have been told by chain engineers that the hard chrome plating on a cutter is just for protection against abrasion. That it cannot be 'sharpened' and does not contribute to the cutting. Some guys remove the chrome from their 'race chains' for this reason, when removing every gram of weight. The questions came up when discussing the Oregon 'MultiCut' / 'DuraCut' chains with the thicker chrome plating.
https://www.oregonproducts.com/en/p...racut-saw-chain-and-guide-bars/c/duracut-sc-p

6. I have seen the chrome curl up and flake off on grinder 'burned' cutters; so I you want to keep it on, overheating is not a good idea.

I like the idea of incrementally converting a cross cut chain to a ripping profile to get more usable life out of it.



BobL said:


> Talk about nerdy chain stuff eh!



That's what these forums are all about!

Philbert


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## BobL (Feb 14, 2020)

Some good points there especially about the hardened cutters being near impossible to file. Thanks


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## frank_ (Feb 15, 2020)

my understanding is that steel is hardened by heating it red hot then quenching.
then it can be tempered/softened by heating it blue and then leaving it to cool naturally.
so getting it blue hot by grinding it too aggressively will actually SOFTEN the tip


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## Philbert (Feb 15, 2020)

frank_ said:


> my understanding is that steel is hardened by heating it red hot then quenching.
> then it can be tempered/softened by heating it blue and then leaving it to cool naturally.
> so getting it blue hot by grinding it too aggressively will actually SOFTEN the tip


A common misunderstanding. What happens is that, unlike a large piece of steel which retains a large thermal mass, the very thin metal at the cutter edges cools very quickly; an engineer referred to this an '_air quench_'. https://www.sst.net/air-quenching-steel/

Theory aside, try filing a cutter that has been overheated by a grinder; even a new file slides over it like a knife on buttered glass. It is usually possible to grind through / past this hardened area, making the cutter edges fileable once more. It can be prevented by taking lots of small taps with the grinder, and dressing the grinding wheel frequently to maintain fresh abrasive that cuts/scrapes/abrades the steel, instead of rubbing dull abrasive against it, which causes friction.

Philbert


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## frank_ (Feb 15, 2020)

that link ^ describes compressed air being "forced over the piece to cool it down " tho
my experience of burning out drills by getting them too hot always makes the tip of the drill go soft
and you have to grind loads off the end of the drill to get back down to the hard part


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## Philbert (Feb 15, 2020)

frank_ said:


> that link ^ describes compressed air being "forced over the piece to cool it down " tho
> my experience of burning out drills by getting them too hot always makes the tip of the drill go soft
> and you have to grind loads off the end of the drill to get back down to the hard part


Again, I was trying to explain the theory, as explained to me by a saw chain engineer, since it seemed contradictory to me too.

But try it. Heat a saw chain cutter blue or black with a dull grinding wheel and then try to file it. It will 'speak for itself'.

Perhaps the alloys used, or the mass of the drill bit, cause it to act differently when overheated in a drilling operation, versus the thin saw cutter edge in a grinding operation. My friends who are metallurgists always talk about the 'art' as well as the 'science' of metal.

Philbert


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## sweepleader (Feb 16, 2020)

Philbert, you are right on as usual, even if you are not certain this time. 

The alloys used for cutting tools, whether for saw chains or drill bits or excavator teeth, are wildly different. They each require their own heat treatments to obtain the best results. 

Air hardening tool steels are common along with oil and water hardening types. The mass and geometry are critical to proper results and tool failures can often be traced to the wrong alloy or heat treat. 

Saw chain cutters have several conflicting requirements for good service. They need to retain a very fragile cutting edge while withstanding impacts and temperature changes as well as abrasive conditions. Material selection and processing steps for this use is not for the faint of heart.


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## rarefish383 (Feb 17, 2020)

Philbert said:


> Some general tips on using a grinder in this thread:
> https://www.arboristsite.com/community/threads/511a-grinder-improvements-tweaks.197073/
> 
> - Take lots of small taps to avoid overheating the cutters.
> ...



A couple years ago a friend, and daughter of one of my Dad's competitors, gave me 7-8 of her dad's old saws, and an old chain grinder. It was top of the line for the time. I tried to find new discs for it and couldn't, but I didn't look all that hard. I tried it out on an old chain on my bench. I tried to take a very small bite and still turned a few teeth purple/blue. When you say take lots of small taps, do you mean take like 1/10 of the bite, then 2/10, 3/10, until you have the full stroke completed? You DO NOT mean take a very shallow, but, full stroke, do you? I was going to sell the grinder at my spring Man Cave Yard Sale. But I may hold on to it and try to learn how to use it properly.


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## rarefish383 (Feb 17, 2020)

I just went and checked and the grinder is a Nielsen model 50. I'm going to do a search and see what I can find out about it.


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## Philbert (Feb 17, 2020)

rarefish383 said:


> When you say take lots of small taps, do you mean take like 1/10 of the bite, then 2/10, 3/10, until you have the full stroke completed? You DO NOT mean take a very shallow, but, full stroke, do you?



Sharpening with a grinder requires a bit of knowledge, skill, and experience (KSE), which is why I encourage people to practice on 'scrap' chain first; intentionally make 'mistakes' (like 'bluing' cutters); then working backwards to find out how far they can go without doing that. Experiment. 'Play'. Take a 'good' chain that you really like, and try to 'copy' those grinder settings (with the motor off): the scales on a grinder might not match up to the angles that you think that you want.

As far as 'small taps' it could be either of what you describe, but I usually do the first for normal sharpening. If a cutter is heavily 'rocked' (damaged), a lot of people will grind the cutter back incrementally, as in your second description. Whatever works for you. Just do not try to hog off a large amount, like with a chop saw.

If you have ever learned Morse code, I describe it as all 'dots' and no 'dashes'. A series of light, gentle taps, until you have reached your intended depth of cut. Experimenting will let you know how long a tap can be, with a specific chain. Smaller chains (1/4", 'Picco', etc.) will heat up faster due to smaller mass.

Dressing the wheel frequently is so important, in my experience, so that you constantly have fresh, sharp abrasive cutting/scraping/abrading the steel, instead of dull abrasive rubbing against it, causing friction.

More, collected tips in this thread:
https://www.arboristsite.com/community/threads/511a-grinder-improvements-tweaks.197073/

I have never used that particular grinder, but several A.S. threads reference it, and several Internet ads pop up when Googling it. Some photos have been lost, but you might be able to contact individual members (_or start a new thread on it!_). 

Philbert


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## rarefish383 (Feb 17, 2020)

Philbert said:


> Sharpening with a grinder requires a bit of knowledge, skill, and experience (KSE), which is why I encourage people to practice on 'scrap' chain first; intentionally make 'mistakes' (like 'bluing' cutters); then working backwards to find out how far they can go without doing that. Experiment. 'Play'. Take a 'good' chain that you really like, and try to 'copy' those grinder settings (with the motor off): the scales on a grinder might not match up to the angles that you think that you want.
> 
> As far as 'small taps' it could be either of what you describe, but I usually do the first for normal sharpening. If a cutter is heavily 'rocked' (damaged), a lot of people will grind the cutter back incrementally, as in your second description. Whatever works for you. Just do not try to hog off a large amount, like with a chop saw.
> 
> ...


When I did a search, of course, the first thing that came up were old AS threads. I like hand filing. I usually hang dull chains on nails for each saw, and with 50 saws, and trying to keep at least 10 running, that's a lot of nails and chains. It would be nice to take a rainy day and knock out a bunch of them.


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## Philbert (Feb 17, 2020)

rarefish383 said:


> I just went and checked and the grinder is a Nielsen model 50. I'm going to do a search and see what I can find out about it.


I started a separate thread on this grinder.

https://www.arboristsite.com/community/threads/bell-nielson-k50-chain-grinder.340222/

Philbert


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## JOEY JENKINS (Mar 23, 2020)

I have milled all kinds of wood from white pine and spruce to red oak, white oak, English and black walnut, maple, hickory and pecan. I have milled with full comp chains and ripping chains. The type chain I used and the sharpening profiles varied. At first because of experiment, then I used my experience to select what worked best for me. On the soft woods like spruce and pine I the ripping chains I used had the rakers filed down to .050" on a 32" or 36" bar with a 066 or 661 powerhead and they worked great. Cleaner teeth were sharpened at 0° across the top plate and slicer teeth at 20° left and right. Almost always with a file. The harder wood I didn't take the rakers down so deep, only .035" or less because they were too aggressive and I spent the whole time holding the saw back to keep it from stalling the chain. The really hard wood like the pecan I didn't see any gain at all with a ripping chain and therefore used a full comp or skip tooth at normal angles. The only thing I usually did different on all my chains is when it's less than half worn out I use a larger size file. On a ⅜ chain I sharpen it with a 7/32" file until half of the top plate is gone then I use a 3/16" file on the last half of the tooth. The hook angle can make a big difference but what works best depends on hardness of the wood, width of the cut, chain length and powerhead size. Milling with a chainsaw isn't easy on the saw or the Sawyer. If what you are doing isn't working well, make drastic changes. If it's going ok but you think there is room for improvement, try subtle changes and keep track of the changes made and the results.
I milled this pecan using a 661, 36" bar and full comp chisel chain. 28" width 10' long and took roughly 3 minutes per cut, stopping at least twice to insert wedges.


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## andy at clover (Mar 23, 2020)

JOEY JENKINS said:


> I have milled all kinds of wood from white pine and spruce to red oak, white oak, English and black walnut, maple, hickory and pecan. I have milled with full comp chains and ripping chains. The type chain I used and the sharpening profiles varied. At first because of experiment, then I used my experience to select what worked best for me. On the soft woods like spruce and pine I the ripping chains I used had the rakers filed down to .050" on a 32" or 36" bar with a 066 or 661 powerhead and they worked great. Cleaner teeth were sharpened at 0° across the top plate and slicer teeth at 20° left and right. Almost always with a file. The harder wood I didn't take the rakers down so deep, only .035" or less because they were too aggressive and I spent the whole time holding the saw back to keep it from stalling the chain. The really hard wood like the pecan I didn't see any gain at all with a ripping chain and therefore used a full comp or skip tooth at normal angles. The only thing I usually did different on all my chains is when it's less than half worn out I use a larger size file. On a ⅜ chain I sharpen it with a 7/32" file until half of the top plate is gone then I use a 3/16" file on the last half of the tooth. The hook angle can make a big difference but what works best depends on hardness of the wood, width of the cut, chain length and powerhead size. Milling with a chainsaw isn't easy on the saw or the Sawyer. If what you are doing isn't working well, make drastic changes. If it's going ok but you think there is room for improvement, try subtle changes and keep track of the changes made and the results.
> I milled this pecan using a 661, 36" bar and full comp chisel chain. 28" width 10' long and took roughly 3 minutes per cut, stopping at least twice to insert wedges.


Interesting 
Since you’ve used both on some truly hard hardwoods... what would you say the advantage if any milling chain provides and at what trade-off. 
I’ve read plenty about milling chain. Many try it and move on back ....curious your experience.
Thx!


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## JOEY JENKINS (Mar 23, 2020)

andy at clover said:


> Interesting
> Since you’ve used both on some truly hard hardwoods... what would you say the advantage if any milling chain provides and at what trade-off.
> I’ve read plenty about milling chain. Many try it and move on back ....curious your experience.
> Thx!


You have to weigh it out. Is it worth the time and extra effort that filing that much chain for the amount of improvement you will achieve, does the smoother cut or faster cut justify it or are you going to plane it afterwards anyway making the smoothness not matter so much? If I am milling soft woods and don't want to waste as much with a rougher cut and will have faster cut times that are easier on my saw then probably worth it. Time is money and just about the only thing in this world that you can not replace. It takes a long time to file long chains with so many different angles. I'm not a spring chicken anymore and my hands can't handle hours of filing after working all day to sharpen a few chains for tomorrow. For me personally, I don't use ripping chains much anymore, mostly because of how difficult it is for me personally to file them. I can grind several chains in half the time it takes to file one long one. Another factor is that I have other options for milling logs that I can move from where they hit the ground and logs that I don't want or need a live edge on. The time you spend researching what's best could have been spent finding out for yourself, which is ultimately what you are probably going to have to do. Just remember that nothing you read anywhere is going to make milling with a chainsaw fast or easy. The basics is what matters most. Larger powerhead is better than one that's too small, only use as long of a bar as needed to reach thru the logs you are milling and shorter chains are easier to pull and keep oiled. Don't over work yourself or your saw, take breaks and cool both you and your saw and both will last longer. Try different things and see what works best for you. Buy the best oil you can for your fuel and lots of chains. If you are serious about milling with a chainsaw, you are going to need them. If you want to make money doing it keep accurate records and pay very close attention. Watch out for screws, nails, spikes and any other metal in the logs. If you see blue or black streaks in the wood there is most likely metal in the log and usually within arms reach from the ground. A drywall screw can nearly destroy a brand new chain in less than a second. Enjoy yourself and the outdoors while creating something you can be proud of.


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## buttercup (Apr 7, 2020)

I'd like to say thanks to Philbert on this topic, though no doubt there are other capacities as well. I Have to do some reading!
Stay safe these days good fellas.


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## Krazo (Apr 9, 2020)

Great thread! Thanks to all for sharing your knowledge. Seriously looking forward to working with my new super jolly grinder. Junk chains first of course


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