hand filing

[Stumper]

Can we come up with an optimal set of angles on our cutter?
Is there an optimal height for our raker?
Do both those angles/measurements change as the cutter is filed back along it's length?

Art Martin maintains that the raker setting should be deeper as the tooth is filed back. Since Art seems to know a lot about making chains cut and because the explanation he offered about how the teeth porpoise through the cut made sense I began setting my depth gauges to a greater gap after getting halfway through the tooth. Performance seems to be enhanced slightly. As far as topplate and sideplate angles go-I outlined my round filing method in the old thread linked previously. One thing that I regret about my lousy picture of a finished tooth in that thread is that the pic appears to show a lot of hook. It wasn't really representative of the actual tooth I shot and I have cut down on the actual hook since then. I still elevate the file handle but keeping the file higher on the tooth results in a sharp corner but a straighter outside sideplate angle. I come very close to the profile of the index marks on Stihl chain-just s l i g h t l y straighter. I suspect that those indices are a pretty good compromise for general use.

 

[Tree Machine]

I have to say I always file parallel to the index marks. I've been wondering if this is actually the ideal. I know dipping the tip of the file downward a bit causes the file to eat more of the top plate nearest you. To compensate, you shift your filing <i>slightly clockwise</i> to stay parallel to the index laser line on the back of the tooth.

Is this sorta what you mean, Stumper, by filing just slightly straighter than the profile of the index marks, or does the line across the top plate that you create actually vary from the index?

I have the equipment to shoot and edit video. It's been an area of study for tha last couple years. However, I'm not so sure I'm the guy, even if it were only presented for free on a private website, not for monetary profit. I'm questioning my own expertise.

 

[Locoweed]

Just have a gorgeous babe in a bikini pointing out the high lights and everyone will rave about your video expertise. <G>

 

[Crofter]

Stumper can you clarify how exactly your file axis is off from the plane of the top cutter and what your theory is about the change in angles effected by that as opposed to having the file axis on the same plane. I am thinking about the confusion that exists in relation to this.

 

[Kneejerk Bombas]

Any single shift in file postion changes all four angles.

 

[Kneejerk Bombas]

I know dipping the tip of the file downward a bit causes the file to eat more of the top plate nearest you. To compensate, you shift your filing <i>slightly clockwise</i> to stay parallel to the index laser line on the back of the tooth.

When you dip the file handle end down, you make a sharper inside top-plate angle. Making the inside top-plate angle sharper will improve cutting speed very slightly, but the you will lose some "stay-sharp" of the top-plate cutting edge. This particular angle does very little actual fiber cutting, so it really has little to no effect.

The bigger change comes when you rotate the file back to compensate for lowering the handle. This makes the inside side-plate angle sharper. As I said, the side plate is important, it cuts most of the wood. A sharper angle will cut faster, but lose "stay-sharp".

 

[Crofter]

Tree machine is talking about dipping the tip but the described results sound like dipping the handle. I am not sure if Stumper is promoting the same thing.

 

[Tree Machine]

Thanks, Crofter. My quote refers to a downward dip of the file tip, a la Stumper. His followup refers to a downward dip of the handle, which no one has referenced as yet. So far, handle is either level or slightly upward. However, the way he describes dipping the handle end downward <i>would</i> create the result he explains.

Either way, to imagine this at the micro level, I'm having to (in my mind) exaggerate these adjustments and look at what the effect would be on that critical side plate angle.

Admittedly, I have always focussed on the angle of the top plate in keeping it parallel with the index mark. I mean, I knew the top plate itself had little to do with cutting as it slopes slightly downward from the point of the tooth inward toward the chain center (at least on full chisel chain).

I figured if that top line I'm filing comes straight and parallel with the index mark, and the point comes to an <i>absolute point</i>, then the side plate angle pretty much falls in line and takes care of itself. From there, the focus has been on the correctness of the file size (dependent on how new or old the chain is in its useful life) and how high up toward the top plate or how low toward the tie straps you are filing. After that, raker height.

I thought I had it pretty well in hand, that I had my sharpening method all tweaked in. Maybe I do. But then again, maybe I don't.

 

[Kneejerk Bombas]

Tree machine is talking about dipping the tip but the described results sound like dipping the handle. I am not sure if Stumper is promoting the same thing.

Ok, that would have the opposite effect, make a blunter inside top-plate angle, and a blunter inside side-plate angle. Slower cutting, better stay-sharp.

 

[Stumper]

Frank, Yes. Raising the handle/dipping the tip. I think that Jim is correct about there being a slight clockwise rotation of the file in relation to the target angle-I really haven't paid attention because I simply file for the desired outside topplate angle.

Jim, What I was talking about was being slightly straighter than the curved index mark on the outside sideplate. As Mike is pointing out-whatever is done with the file changes everyangle on the tooth. Trying to create a sharp, Square corner(Outside) with a round file is problematical. Round ground chain can't do that and in reality round filing can't either BUT, by tipping the file and raising the file into the topplate so that the cutting is taking place slightly nearer the centerline of the round file, then going back to finish the side plate and inside topplate CORNER with a different file setting it is possible to have a corner with good stay sharp, limited beaking and a minimal hook in the sideplate itself. Having said that-the method I use raises questions-the angle on the sideplate below the corner seems wrong-yet the chain cuts better. Chipflow was discussed years ago and may be a factor. I think what this really points to though is Mike's point that the angles at the corner are most important. Sharpness at the trailing edge of the top plate and at the bottom of the sideplate seem to matter little so long as the gullets are opened to accomodate chips.

 

[daddieslilgirl]

well im not exactly sure what rakers are, i assume they are the high points on a chain. ive been dooing it for years (yeah i know i dont know the tech terms i just did it) i do 3 slashes with the file and then the next then after half the chain is done i turn the saw and do the same until all the teeth are done i dont know how i know where i started but i just do. i filed hubbies climbing saw and he was amazed, thought i put a new chain on. nope 3 and 3 and it works everytime. i dont know how to explain it id have to do it so you could see what i mean. lol sorry but thats one thing im really good at, and yes im ????ed proud of it lol

 

[Tree Machine]

Hi Daddieslilgirl. What a great treat to have another female here on site, welcome. Also, not a bad question. Here we are talkin about rakers, but we're all assuming we all know what we're all talkin about. Shame on us.

The 'rakers' are the metal nubs in between the cutting teeth. The cutting teeth, as you know, alternate left / right. in between each of these is a 'raker', also known as a depth guide. The function of these buggers are to prevent the cutting teeth from digging too deeply into the wood and causing the chain to come to a most immediate stop.

When a cutter hits and pulls out a chip of wood, the raker right behind then glides ON the wood, keeping that tooth from being able to further dig in.

If you look at your bar and chain, at eye-level, you will notice that the cutting teeth slope downhill, from the tip of the tooth, going back. As you file the chain, over the course of time, the teeth get shorter, front-to-back, of course, but also, <i>vertically</i>. There is a point where the vertical height of the tooth (the point or cutter tip) will be the same height as the raker in between the teeth. At that point the rakers will not allow the cutting teeth to cut, or the cutting will be very minimal. When this happens, you can have your teeth razor sharp to perfection, but the chain will be cutting agonizingly slow, and spitting out powdery dust at best. This is when you take a flat file and 'knock down the rakers', or file them down shorter so the teeth can again get a bite into the wood.

Stumper said something earlier, that if you take a small <b>flat file</b> (bastard file), turn it on it's side, lay it on the very points of two adjacent cutting teeth and look at the place in between them (the raker). Look at the air space between the top of that raker, and the bottom side of the file. This tiny little gap is what determines how deep that cutting tooth is gonna dig in.

Did that clarify things? Thank you for asking the question.

 

[daddieslilgirl]

well forget that ive never used a flat file in my life! lol my brother or my dad does it but thanks for the info

 

[ROLLACOSTA]

Well im exceedingly wealthy ! i just throw dull chains away .

 

[Tree Machine]

Did you get exceedingly wealthy being a tree guy? That would be a neat trick.

 

[Ax-man]

Did Mike abandon the thread??? I thought he was going to discuss more angles as the tooth is being filed back to nothing.

Larry

 

[Tree Machine]

Mike has a business to run, and a life outside of this site. It's Spring. He's busy. I think he's put a generous amount of time and effort into spearheading chain class. We young grasshoppas must...learn.....patience, give Great Chainmaster time to prepare next lesson. Grasshoppa Axe-man cut Chainmasta some slack. :jester:

 

[ROLLACOSTA]

Did you get exceedingly wealthy being a tree guy? That would be a neat trick.

no i made my fortune selling dull chains to the third world..

 

[Tree Machine]

I believe you, Rolla, because I made my fortune selling them old used bars.

Hey, since the title of this thread is 'Hand-filing' and you sharpen even <u>square-ground</u> by hand, eventually this thread might reference any square-ground, hand-filing references we have active or archived.

I asked a few questions over in 'Chainsaw' and I believe I may begin running square-ground. My entire life of chainsaw working has been in using round-ground chain. I've never run square-ground; had never even <i>considered</i> doing it. Now, in a moments instant, I feel the need to shift, to stir a little change into a lifelong assumption that round-ground chain was the only way to go.

I thought square chisel chain came that way from the factory, and it was some rare, specialty-use chain for racing saws. Apparently, you start with round-ground chain and <i>convert it</i> by using a different shaped file and learning a litlle different filing approach.

Huh.

Never made the connection.


But for now, let's hang with the round-filing discussion.

 

[Crofter]

Tree Machine. It is the same chain. Just a different grind on it. It can also be converted back and forth either way. Get some factory square, use it, try it, and if you can't square file it or find someone with a grinder, just round file it and never miss a beat.