Signs That Your Chain Is Sharp (Or Dull)?

[SteveSr]

Steve Great question - I would like to hear suggestions on this too!!!

Around here we have dead dry trees that fall on trails. They are rotten and cutting produces fine chips and powder. Where as a green tree poops out nice chips with a sharp chain while the chip size reduces as chain dulls. Sharp chain feeds better with little effort and as your example the user needed to push on it to cut. Great to have a second chainsaw with sharp chain that the user could use to see and feel the difference.

I feel for you for training users. Over time one will experience sharp versus dull, knowledge of the behavior and feel for it while cutting. That comes with time with the chainsaw.

I guess most won't pick this up by textbooks and talking to them. Having them use a dull and sharp chain to see and feel the difference might be the only way for some to learn.

Going extreme have them start cutting with a sharp chain and stop them and throw a little fine dirt in the kerf dulling the chain to quickly experience the difference. Then teach sharping that chain in the field and start cutting again.

Most classes don't spend much time on this or at all, so how does your new users learn?

I'm not sure a quick teaching method reaches all the students. Some students can watch a video and get it but some will be needing to actually experience it in person. Some will nod their heads but really not understanding what you are saying. In a group training who wants to be that person to be embarrassed asking questions.

Patrick

Yesterday we were working on a 20" green red oak blow down. I had a second saw, a Husky 345 (45cc) and both had 16" B&C. At the end of the session I handed him the Husky and asked him to make the last cut.

Obviously this was bar buried from one side. After he finished I asked him if he noticed any difference. He said that the chain seemed "grabbier" and suggested "different" sharpening than the chain on his saw. I said that the difference was that the chain on the Husky was sharp and his wasn't. I also pointed out the HP difference between the two saws. In retrospect we should have had a contest between the two saws.

 

[SteveSr]

A sharp chain will pull itself thru the wood. Leaning on it is a way to compensate.

I think that this is a better metric. We may do a demo at the next class in December.

 

[SteveSr]

Have examples of a sharp chain and a dull chain- and provide a magnifying glass.

Magnifying glass is a key point since a lot of our sawyers are older retirees.

Here is what I use:
https://doneganoptical.com/product/optivisor/

 

[SteveSr]

It's all good to be able to tell sharp from dull, now how do you convince someone who knows that he is cutting with a dull chain to stop trying to force it and sharpen the damn thing.

Good point. Fortunately or unfortunately a chainsaw has a motor which can be used to compensate for a non-optimally sharpened chain.

A user with a cross cut or hand saw would know right away. This is likely how the old cross cut saws got the nickname "misery whips" as it took special skills and equipment to sharpen them which most users didn't possess.

 

[J D]

For demonstration purposes you could get a few sections of harvester chain & file it to suit the examples you want. Being larger it will be easier to see without additional viewing aids

 

[Okie]

Lay into some dead blackjack limbs with a sharp chain right at dark and notice the results. You can see sparks coming off the chain like it's hitting rocks or a pieces of metal.

Sometimes a dead elm will do the same but Dead Black jacks will really dull a chain fast.
Some things about getting and keeping a chain sharp comes from experience in the woods and will more likely be remembered when the OP of the saw experiences such.
Some things are just not in THE CHAINSAW HOW TO BOOK.

 

[Captain Bruce]

Steve Great question - I would like to hear suggestions on this too!!!

Around here we have dead dry trees that fall on trails. They are rotten and cutting produces fine chips and powder. Where as a green tree poops out nice chips with a sharp chain while the chip size reduces as chain dulls. Sharp chain feeds better with little effort and as your example the user needed to push on it to cut. Great to have a second chainsaw with sharp chain that the user could use to see and feel the difference.

I feel for you for training users. Over time one will experience sharp versus dull, knowledge of the behavior and feel for it while cutting. That comes with time with the chainsaw.

I guess most won't pick this up by textbooks and talking to them. Having them use a dull and sharp chain to see and feel the difference might be the only way for some to learn.

Going extreme have them start cutting with a sharp chain and stop them and throw a little fine dirt in the kerf dulling the chain to quickly experience the difference. Then teach sharping that chain in the field and start cutting again.

Most classes don't spend much time on this or at all, so how does your new users learn?

I'm not sure a quick teaching method reaches all the students. Some students can watch a video and get it but some will be needing to actually experience it in person. Some will nod their heads but really not understanding what you are saying. In a group training who wants to be that person to be embarrassed asking questions.

Patrick

Wise words from Patrick. EVERY woodsman, farmer, pro arborist, and land mgmt. tech, Hot Spotters to be sure........understand that the chain is what does the work. When the bar wears, the chain wears. When the chain wear from a used up bar, affects the cutting, its time for the tailgate, and tool kit. Thats 101.

Laying into dead pulp fluff yields dust, looking for the air filter, oiler, and chain. Save those worn out chains with missing teeth. Never know when a hedgerow with old wire will come along..............

 

[HansFranz]

A bar/chain that smokes and catches on fire is a good clue that the "blade" needs a "touch up."

 

[Philbert]

Great question. I also teach volunteers, and have a number of comments. I’ll start with my ‘winner’:



A strong, directional light will highlight dull edges. The student has to know what to look for, so it helps to show this along an explanation is how a cutter works (what the top plate does; what the side plate does; etc.).

This is also important when teaching sharpening. Regardless of the method (file, grinder, etc.) the person has to know when they are ‘done’; what a sharp cutter looks like.

Philbert

 

[Philbert]

Don't know if this will help, but I use a toothpick when sharpening or checking for sharp - you should be able to shave the toothpick with the cutters very smoothly and produce nice shavings without any resistance.

I will also lightly draw my thumb up, across an edge to judge the sharpness, but some groups do not allow sawyers to touch a chain without gloves.

Similar to @anynameyouwish , above, I will teach them to pick a small, green, twig in the woods, and draw it across the edge. Shave the green bark off: sharp edge. Slides over the edge without grabbing: smooth / dull edge.

Philbert

 

[Philbert]

As noted in several posts, the ‘proof’ is how the chain cuts in the wood. I also like to have students cut with a dull chain and a sharp chain in the exact same log to appreciate the difference.

I teach them to pick up a handful of chips afterwards. Although, you can be deceived by a punky log, I tell them to look for chips that resemble ‘cole slaw’ more than ‘corn meal’. If anyone has better, common things to use for comparison, I am open to suggestions!

Philbert

 

[wardog]

If you cant figure out if a chain is sharp or dull you shouldn't be cutting wood. Steve

Does that same mindset hold for using a kitchen knife to cut meat? Beings I had always hunted as well as fished and processed many, many animals, I got a very good lesson on WHAT a sharp knife was AFTER having to use one day in and day out for 8 to 10 hours per day as a federal USDA meat and poultry inspector, trying to keep up with the high-speed slaughter lines. What I thought was sharp wasn't even close and the process of sharpening one was quite a difficult task to learn exactly what was going with doing so. It took me quite a long time to get the hang of it and that steeling a knife is NOT sharpening it. I spent an entire 30+ year career in that profession and witnessed numerous inspectors as well as butchers that never did learn how to sharpen their knives. Many of the big corporate processors have an entire knife sharpening department that sharpens ALL the knives used in the plant on machines because so many do not know a sharp one from a dull one neither do they have the skill to sharpen their own. As inspectors we had to learn to do so with a sharpening stone and keep our own equipment sharp. It doesn't take long to know the difference in sharp and dull when the animals are coming at you nonstop. Therein lies the difference in what one needs to figure out when using a piece of equipment sporadically or for a living. Even a hand knife can and will harm you badly. I have seen very few housewives using knives in the kitchen actually know a sharp one from a dull one, so I guess they shouldn't be cutting meat. I taught my wife how to steel the knives so as to help keep a straight edge and she at least knows how that helps but I have not taught her how to actually sharpen one on a stone as that is a process that takes time.

 

[lone wolf]

Holy crap it aint rocket science if it throws larger chips its sharp if it throws powder its dull .

 

[LuDookie]

If you think chainsaw work is loathsome, like most people that own them, then you aren’t keeping your chain sharp. Those who have figured it out and are good at sharpening are usually looking for stuff to cut.

 

[Maintenance supervisor]

I use a giant Oregon tooth for display and instruction also.
Just to be absolutely clear, I like for everyone to have the same style of chain also. This is to ensure that the angles don't get confusing for beginners. As a very round semi-chisel is better filled with a 30° degree angle to the top plate and 90° to the bar.

 

[HarleyT]

I bought the countertop Display from Oregon that is a large model of a full chisel, and can show them what they should be trying to achieve.

 

[SteveSr]

I will also lightly draw my thumb up, across an edge to judge the sharpness, but some groups do not allow sawyers to touch a chain without gloves.

Similar to @anynameyouwish , above, I will teach them to pick a small, green, twig in the woods, and draw it across the edge. Shave the green bark off: sharp edge. Slides over the edge without grabbing: smooth / dull edge.

Philbert

What about a freshly filed chain that still has the burr on it? It may pass this test because of the burr and not because the cutter is really sharp.

 

[SteveSr]

Great question. I also teach volunteers, and have a number of comments. I’ll start with my ‘winner’:

View attachment 1023184

A strong, directional light will highlight dull edges. The student has to know what to look for, so it helps to show this along an explanation is how a cutter works (what the top plate does; what the side plate does; etc.).

This is also important when teaching sharpening. Regardless of the method (file, grinder, etc.) the person has to know when they are ‘done’; what a sharp cutter looks like.

Philbert

I agree that this is a good indicator but a lot of our sawyers, including myself, are in what my ophthalmologist calls "optical purgatory". Since I worked in electronics I had already gotten used to using extra magnification unlike most of our students (who may still be in denial).

 

[Lionsfan]

Holy crap it aint rocket science if it throws larger chips its sharp if it throws powder its dull .

You betcha'!!!

 

[Philbert]

What about a freshly filed chain that still has the burr on it? It may pass this test because of the burr and not because the cutter is really sharp.

I agree that this is a good indicator but a lot of our sawyers, including myself, are in what my ophthalmologist calls "optical purgatory".

These are just ‘signs’. Something to give new folks as indicators while they are developing knowledge, skill, and experience.

Any indicator can yield a false positive or negative. It’s helpful to have something to go by before they put away all the sharpening gear and try cutting again.

Over time, they will get better at using certain indicators. Maybe some will use a magnifying glass: I once made the mistake of assuming my prescription safety glasses did not need the same progressive bifocal correction as my regular glasses (never did that again). Some may carry a highly directional flashlight. The burr is something else that they will learn.

You are just pointing them in the right direction: some things take time to learn. Start with ‘good enough’, and let the motivated guys continuously improve.

Philbert