Grinding chain loops and the difference between left and right hand cutters..

[James Sawyer]

Well, some of that regarding hand filing/sharpening is probably true with some loggers never a professional. I see young people these days that don't want work, can't even use a tape. I guess I'm too old school. My Dad ran a cutting company prior to retiring and he was pretty tough to work for. Things were change back in late 90's and early 2000, cutters were getting paid by the day instead by the Board Foot on the ground. But I know if you didn't get the timber down, he got someone else...too many good people out work... I couldn't count how many times I heard him say that! You better not break timber or screw up the lay. Plus, if you buck crooked and the logger got docked at the Mill you were hosed. Working for him... you were one min. late to work ...you when home without pay, if you made it to work on time the next day.... you had a job or he couldn't use ya! Seen that a few times too! So, if you didn't know how keep a sharp chain well you wouldn't work out to well working for my dad. He hand filed or changed out chains, which is what I do. Dad had a Silvey' but I never saw him use it that much. I lived in some of he's log camps as kid, and I guess I never experienced fallers that didn't care about how sharp their chains where. Now days they don't have as many guys falling on the ground... it all machines. But large timber they still have cut the butts off that first log in the landing because the processor can't handle it. I don't see how not knowing how to take care of your saw unless it was a new guy on landing, I'm pretty sure they learn pretty quick. I've never known a logger that load out day didn't matter.

 

[rtrsam]

Regarding the original question: does it matter if the cutters are the same length on one side or the other? In my experience, sort of. If you're using a long bar (think 48" or longer) cutting big timber, then the minor difference in cutting aggression by having all the perfectly sharp teeth on one side of the chain a little longer than the perfectly sharp teeth on the other side, might make the saw cut a little crooked. Especially if the chain hit something that required all the teeth on one side to be ground a lot more than on the other side. But a good cutter would notice this in big timber and likely be able to compensate for it somewhat by steering the saw a little. And then he or she would try to figure out what's wrong and see the cutter lengths are different and get it dealt with.

Chains are expensive, but when you add up the actual cost per hour of being on a jobsite, they're pretty cheap considering your entire ability to be productive is dependent on a sharp chain. If you're cutting for scale you can bet you'll have nothing but perfectly sharpened razor sharp chains.

Generally when someone starts to gripe about a saw cutting crooked, they start with "the bar's bent!" then progress to "the rakers are too high!" and the true sophisticates say " the bar rails are uneven!" In fact, most of the time it's just a dull chain, as in the teeth are not sharp.

If left and right side teeth are sharp, and the rakers somewhat consistent and within reasonable proximity to factory spec, the chain will cut straight and quickly, especially on shorter bar length saws.

 

[bwalker]

If you look at many hand filed changes the right and left cutters not only do not match angle wise they are often all different lengths. Assuming the the angles are all close(most often they aren't) uneven cutters cause more drag as some of the side plates drag and others don't cut at all. When look at a cut log this is readily apparent as you can see the drag marks where some cutters are more aggressive than others.

 

[cumminstinkerer]

@bwalker I agree, the 084av I put back together a few weeks ago and did a quick dress on the chain shows it badly, plus it veers in the cut, I need to get more time and sit down and grind the chain correctly and see if it cures all of the above, the bar could be bent or worn uneven, it came to me as kit, lol, need some time to play around but got a lot of projects! Thank you all for the replies, I was able to learn a few things throughout the thread!

 

[Sidecarflip]

well... IF you plan on charging money, then the teeth should be even from side to side, and preferably all the way around the loop, the depth gauges(rakers) should be .02-.035 BELOW the top if the cutting edge (depth is dependent on cutting conditions, tooth count hp etc etc .030 is fairly standard) The entire point of paying someone to grind chains is to "true them up" and keep the hand filing from going wildly astray. Yes you could simply grind until sharp and make the depth gauges match each tooth, which is a compromise and just fine for your own uses, not something a self described machinist would ever charge money for though.

as for your grinder not repeating side to side, all of them are a little less then accurate, some are adjustable, some are not, Oregon products are no better then harbor freight, they just cost more, even the old Silvey grinders which are arguably the top of the line skookum choochers still need to be adjusted to get consistency left to right, the Simmingtons too for that matter. Its almost like someone claiming to be a machinist would just ass-u-me that the head on a bridgeport mill is dialed in and ready to work, without checking it first

One would think a card carrying "journeyman" tool and die maker would already know most of this.

As for your CBN wheels, it may be fine for you, however if you do heat the tooth up red hot, it will air quench and harden, so when your paying customer attempts to file it back to true... he's going to tear up a couple files quick fast in a hurry, again, this is something a "machinist" should already know. (the carborundom wheels are supposed to cut, rather then abrade and shouldn't make much heat, but they can, and the diamond wheels can and will create as much or more heat then the traditional stone wheels, again things a "machinist" should already know.) What generally happens when some ignoramus overheats a tooth is, they take it to a shop that does in fact know what they are talking about, they then spend a considerable amount of time hand grinding the hardened spots out of the teeth, then cutting all the remaining teeth back to that depth, so that when the customer does use the chain, it cuts straight, fast and true. A tool and die maker would already know all this though.

I do charge, always and I seem to get more chains each time from different customers as well. I'm going to delegate the sharpening to one of my employees shortly, I have a big aluminum job coming in that needs to be run on the CNC plasma table, then fitted up and TIG welded for a sub assembly for a Stellantis sub contractor. Just waiting for the aluminum sheet to arrive. I always check the depth gages but that depends entirely on what saw they are running the loops on. If it's say an in tree saw (small loop), I don't cut the rakers if they are protruding above the dept gage slightly because in tree saws (small loops) would eat too much power and most likely chatter. The big loops are all checked and if the are proud I grind them on a separate grinder.

Don't insult my intelligence, I know EXACTLY what I'm doing and that includes not only grinding chain, sharpening chipper knives and running (and owning) a short run job and fabrication shop and we are (at least I am AWS certified in MIG, TIG welding and I'm about to get my Nuclear certification as well)

Again, if the chains are rocked, I'll grind them until the worst tooth is whole again, but on chains that aren't, I don't. Considering how expensive saw chain loops have gotten ( at least quality ones and my customers don't run the Hipa chains or at least I've never seen one come through the shop yet).. Why take most of the cutting life out of a tooth (teeth) when it's not necessary anyway?

Every loop I get it is ultrasonically cleaned before grinding, then inspected for corrosion and if the drive links are badly corroded, they go in a different pile to be returned to the customer or scrapped as the situation deems. They they get dressed and then re-oiled and sequestered in identical length loops and zip tied together. Never had ONE customer complain either.

I'm even getting inquires for grinding chipper knives and anvils not local customers but I've been declining that because shipping is so expensive today. It does keep my big Kent auto feed grinder busy however, Most of the surface grinding is done on sensitive feed toolroom grinders.

Chains and knives and anvils are but a value added part of my business and we had a banner year, in fact I'm declining work presently. Got too much on my plate as it is and no, not hiring anyone else. I vet my employees carefully. One, they have to be well versed in all aspects of machine work because we do lots of different things, two, they have to get along with me and that can be difficult at times and three, I pay very well. I have to as I'm a terrible boss.

No I don't go looking for work, it comes to me and it's 99% word of mouth. I do have to quote commercial work however and today that takes a very sharp pencil.

 

[Sidecarflip]

Says the guy who threatened to leave the site, but was back for more hrs later.

Hazelnut coffee creamer blows. Tastes like stale, wet pencil shavings smell...so what... I come here when I need a diversion from being bored late at night or in the morning before it's time to go to work...

I prefer 'Sweet and Creamy Coffee Mate myself 'cause I reflects my personality... sweet and creamy, just ask my wife....

next?

 

[Sidecarflip]

Even for the guys that have no bias on their cuts, that makes the left & right side cutters equally dull. I've also run a small engine repair facility

Once I started replacing tired engines with HF Preds, I quit repairing them. Now I landfill them and go buy a new cheap Chinese engine.... Much easier and keeps my hands cleaner too...lol

 

[farmhard]

Most of the destroyed junk that come my way have vise marks all over the bars and I attribute it to how the vise is mounted on the bench and a person continually using more pressure and longer strokes continually on one side. Imagine a wall in the way and not being able to get a powerhead mounted on 1 side. For some reason Poulans are "notorious" for this phenomenon.

 

[Sidecarflip]

With my grinder, the Left cutters tend to come out a hair shorter than the Right.

I can always take a little more off the Right, if too long, but hard to put more back on.

Just important to find something that works for you.


CBN wheels can overheat a chain.

It was one of the first things I tried when I bought a pair, several years ago. Also, did not like the finish they produced. Went back to conventional wheels.

Philbert

I agree 100%. You reef on the wheel when grinding it's gonna heat the cutter and destroy the temper and harden it, don't matter if you use a vitreous wheel it a CBN wheel is, you don't have to radius dress it at all. Just clean it with a soft white stone every few loops.

When grinding with a vitreous stone wheel and it gets loaded up, it will heat a cutter much faster. That also applies to surface grinder wheels (I have 3 surface grinders in the shop and the wheels must be dressed regularly as the load up and once they do, they will burn whatever you are grinding plus they will leave 'chatter marks' on the part. Also why they makes wheels in different grits and various grinding materials. I have a rack on the wall with various grades of wheels in various compositions for different materials.

You can roast any cutter with very little effort. Just reef on the grinder handle.

I run the CBN wheels just because I don't have to fiddle with them as much and the run very true with no vibration (unless the motor spindle isn't running true) and I can leave the side guards off entirely (which are a PITA anyway) because they won't come apart unexpectedly. Seems as though all these grinders make the side guards a Chinese Puzzle today.

I will say the Vevor Chinese grinder I bought for 100 bucks (delivered from Amazonian), the arbor hole was tad bigger than the arbor hole in the CBN cutter so, I had to chuck it up in one of my toolroom lathes and skim cut the bore to fit. Typical Chinese machining. Other than that, it was a dead wringer for the Oregon / Tecomec and the grind depth stop on the Vervor is light years better than either of my Oregon / Tecomec ones.

 

[Sidecarflip]

Most of the destroyed junk that come my way have vise marks all over the bars and I attribute it to how the vise is mounted on the bench and a person continually using more pressure and longer strokes continually on one side. Imagine a wall in the way and not being able to get a powerhead mounted on 1 side. For some reason Poulans are "notorious" for this phenomenon.

What soft jaws in a bench vise are for. I use aluminum or brass myself when I do, do that which is rare. Gave my 'stump vise' and hand files away after I got the grinders and I just carry a a spare loop when I'm out cutting anyway. Soon as I start to see pitch building up on the backside of a cutter, I change out the loop. In reality don't matter is it's a Chinses saw or a European saw, dull chains don't cut well, rob power and just keep making sawdust.

 

[farmhard]

Subtle sarcasm on my part. I should clarify the filing is done more in one direction. Usually if it's a Poulan or HD Homelite UT I just turn the chain upside down and end for end.
There wash a stupid number of them being returned where homeowners couldn't mount bars or chains properly.

 

[Sidecarflip]

I see that in the shop where I fiddle part time. Amazing how when you put the loop on backwards how it won't cut anything or the old, I cannot get the bar on now...duh. Finally, the floppy chain loop that derails and then they have to pay for non warranty repairs.

One thing I've learned over the time I've worked at the dealership and that is people today cannot follow simple instructions or ever bother to read owners manuals. One thing i do when I deliver a new Kubota tractor to a customer, I tell them to read the owners manuals and I make them sign a hold harmless agreement that they will follow it, especially when it comes to the new T4 final ECM controlled tractors as any deviation from the outlined regen procedures plainly spelled out in the owners manual will result in warranty and non warranty repairs. People spend BIG BUCKS on a new unit and then don't have the grey matter to read the manual...amazing.

 

[pdqdl]

With my grinder, the Left cutters tend to come out a hair shorter than the Right.

I can always take a little more off the Right, if too long, but hard to put more back on.

Just important to find something that works for you.

There is an easy fix for that, you know.

If your cutters are coming out with different lengths but you aren't changing your grind position between sides, then your rails clamping the chain are almost certainly not centered in the middle of the wheel for that gauge of chain. There will be small adjustments available to move the "fixed" rail closest to the motor in or out to adjust the "center point". Then you will need to change your clamping tightness accordingly to match the chain gauge you are grinding.
A well worn rail can cause that inaccuracy, too.

If you were really technical about your grinding, you would reset the center-line for each chain gauge that you happen to grind or have a different machine set up for each gauge. If you think that isn't a factor, find some .043 pico chain, sharpen it with no adjustments, and then do a .063 chain and compare closely.
You'll see it then.

 

[pdqdl]

That is when dropping trees. Most firewood cutters, spend >90% of their cutting with a tree on the ground, where the left/right cutting will have no bias on the chain.

That wasn't quite my point. That bias cutting is mostly seen when guys are cutting underbrush to get to the tree they are dropping. Or just clearing out around the fencelines, or whatever else they are cutting underbrush.

And yes, cleaning up stumps close to the ground generally hits the right side cutters in the dirt more than the left side.

 

[pdqdl]

Agreed. I am very right handed and havn't ever found a way to cut the right teeth with the right hand. You just practice and force your left hand to do the job, pay attention to the teeth and rakers. A new file is always easier to get good results with and doesn't chatter as much. Putting the saw upside down in the vice can help get the engine out of the way.

I just turn the saw around and push the file towards the engine. Or turn the file around and sharpen with a pull stroke instead of a push stroke.

I've even played around with sharpening push strokes with the left hand, but that isn't my favorite method.

 

[Philbert]

There is an easy fix for that, you know.

If your cutters are coming out with different lengths but you aren't changing your grind position between sides, then your rails clamping the chain are almost certainly not centered in the middle of the wheel for that gauge of chain. There will be small adjustments available to move the "fixed" rail closest to the motor in or out to adjust the "center point". Then you will need to change your clamping tightness accordingly to match the chain gauge you are grinding.
A well worn rail can cause that inaccuracy, too.

If you were really technical about your grinding, you would reset the center-line for each chain gauge that you happen to grind or have a different machine set up for each gauge. If you think that isn't a factor, find some .043 pico chain, sharpen it with no adjustments, and then do a .063 chain and compare closely.
You'll see it then.

I’ve done the vise centering thing.

But you also have to do it with each wheel, and as they wear, because it changes with wheel diameter.

Oregon 520-120 has a nice, sliding base on their vise, to make this wheel wear adjustment little easier.

It also has to do with the way that the grinding wheel pivots into the chain, versus dropping vertically straight down: different parts of the wheels hit the R and L cutters, at different angles.

When I was taught to use some older, surveying equipment, I was instructed to accept inaccuracies and wear, but to work in ways that canceled the errors out.

So, I center my grinders as best as I can, but assume and expect ‘errors’. Then, I use work methods which ‘cancel those out’, as best as I reasonably can, as well.

Philbert

 

[Philbert]

One thing I've learned over the time I've worked at the dealership and that is people today cannot follow simple instructions or ever bother to read owners manuals.

Is that the ‘magazine’, with all those pictures, that came with my new thing? The one I threw out with the packaging materials?

I always encourage people to read the manuals that come with their saws, etc., and to download a copy if needed.

In fairness, some appear to have been written by product liability lawyers (e.g. starting with 3 pages on proper extension cord use, for any electrical appliance), and are unreadable by an ‘average’ person.

Some, like the joke about old, software manuals, are ‘written by people who don’t need them, for people who can’t read them’.

The manuals for many chainsaw grinders fit the above. Many are unintelligible in many languages by using pictographs that are clear only to the author.

The Oregon 511A is one of the best chain grinder manuals, but I did not understand it until after I had figured out a lot of things on my own .

*But afterwards, I still went back and read it again, and I learned stuff! *

So, I encourage people to go back, snd read the manuals, for things they already have.

Philbert

 

[JD Guy]

So, after reading and re-reading this thread I have what’s likely a very dumb question. On my Oregon 520-120 should I recenter the grinding wheel when I change from right to left (or visa versa) cutters on every chain to maintain left/right cutter length’s accuracy?
Thanks Much!

Oh, while I’m showing my ignorance, I have been recentering my chain stop behind the cutter when changing from one side to the other. Is that also a proper procedure?

 

[Philbert]

On my Oregon 520-120 should I recenter the grinding wheel when I change from right to left (or visa versa) cutters on every chain to maintain left/right cutter length’s accuracy?

No.

Center the wheel when changing between different size (diameter) grinding wheels, or to compensate for wear.

But do check, and make minor adjustments, as noted, when changing sides.

Oh, while I’m showing my ignorance, I have been recentering my chain stop behind the cutter when changing from one side to the other.

Yes.

Do this, or you may hit it with the grinding wheel, especially, with shorter cutters.

Philbert

 

[JD Guy]

No.

Center the wheel when changing between different size (diameter) grinding wheels, or to compensate for wear.

But do check, and make minor adjustments, as noted, when changing sides.



Yes.

Do this, or you may hit it with the grinding wheel, especially, with shorter cutters.

Philbert

Great, thanks much for the advice Philbert!! So, if I understand correctly when changing from right side cutters to left side I should not have to make any adjustments? You mention “minor” potential adjustments. What might those be?

I’m trying to get better with my grinding methods and results so once again I do apologize for my relative lack of experience