Chain sharpening Performance Tweaker

[lastradicaldude]

Mike it would really help if you would read the original post again. I am not talking about tweaking square ground chain but rather round chisel. :bang: Now maybe you expect all of us reading this post to extrapolate the facts from information that, however enlightening, fails in relevancy. If you have some info from Madsens on round ground chisel then by all means post it. I am certainly open to education.

 

[Kneejerk Bombas]

The point of the madsen's site link was to help us talk the same language. There are four cutter angles that we adjust when we file, round or square. Even though a round file leaves a rounded angle, it is industry standard to talk about the angle as an average of the curves.
Think of it like this, when you push more down on your round file, and only 10% of it is above the top plate, you have lowered the outside side plate angle. You have increased the hook.
If you lift on your file and 30% of the file is above the top plate, you have increased the outside side plate angle. You have decreased the hook.
Even though you are filing round, all the same mechanics are in play.
There is no magic in using a smaller file. All you're doing is decreasing the outside side plate angle, what we call increasing the hook, and making it grab more, unfortunately, not cut faster.
Here's an example of the angle we're talking about. It's a straight angle, but on a round ground chain. My point here is there is nothing irrelevant about the Madsen's link.
http://www.arboristsite.com/attachment.php?attachmentid=22335&d=1112157197

 

[Stumper]

I just want to go on record in support of Mike. The Maashole is known far and wide as a real fart smeller.

 

[lastradicaldude]

Phewww!

Do you have to be a real fart smeller to get people on this site to join forces? Think I'll pass!

 

[Kneejerk Bombas]

Dang it Sumper! I'm a smart feller!

 

[lastradicaldude]

Question?

Mike, by your continued oposition to my suggested methods, am I to conclude that you believe it inadvisable to reduce the diameter of the sharpening file as the tooth is worn shorter on round ground pro chisel chain?

 

[Cut4fun]

Take some pics and post your cutters for us. Then take a stock chain with a digital stop watch and make some cuts for time. Just do one cut then you dont have operator error in the cut times on change overs.
I tested some of my faster chains yesterday in some dry scyamore for 3 CUTS. I trust my change overs for timing.
Found my chain hand filed by me with 8T was slower then a good machine sharpened chain on the same saw running 7T. YES, I need to run the test with a 8T and the machine sharp chain. But couldnt get it together and lost patience so I ran the 7T. My hand chain in 3 cuts ran 3.59 and the machine chain ran 3.47. That 1 tenth and 2 hundreds of a second means something to me, because that means I just lost the race at the gtg. But by watching the cut and chip size flying off chains you wouldnt think one was faster then the other. But 4 cut times by each chain showed the one was faster everytime.
I thank this is all people are asking of you. Show us comparisons of your chain and a stock chain. So we can see if it does cut faster.
Chip size means nothing in fast cuts. I have a chain with almost no raker to speak of, BIG chips, slow times, slower cutting.

 

[Cut4fun]

update on chain test

I put the good chain on today with 8T and ran 2.78 - 2.97 in 3 cuts 7x7 dry sycamore.

2.78 - 2.97 8T machine sq
3.47 - 3.50 7T machine sq
3.59 - 3.81 8T hand filed sq

This is what people like to see. Proof that something is faster and not making it slower by trying new things.

 

[Kneejerk Bombas]

Mike, by your continued oposition to my suggested methods, am I to conclude that you believe it inadvisable to reduce the diameter of the sharpening file as the tooth is worn shorter on round ground pro chisel chain?

lastradicaldude, I don't worry about cutting into the tie straps with my file, and I believe the biger the diameter the round file you use, the straighter the out side side plate angle is. The straighter the out side side plate angle is, the faster it will cut.
You want that outside side plate angle to be such that it hits the wood fibers at exactly 90 degrees as you cut. The problem is, the cutter rocks back and forth as it bounces through the wood (unless you are ripping). So you need to move the angle down to the average angle the side plate hits the fibers, about 87 degrees give or take a degree or two.


Good post Cut for fun, that's my point, the feel or chip size has nothing to do with how fast a chain cuts.
I like to set up a log and make a cut, while the timer shouts out the time, then make another cut, listen to the time, repeat five or six times real fast.
You're right, the cross overs can mess up the time if you're trying to determine how fast a chain is.

 

[Cut4fun]

Partner 5000 +

Just for giggles today. I broke out the STOCK Partner 5000 + and put on a 3/8 rim 7T and 16" bar with a fresh loop of stihl RS full round chisel factory sharp. Not touched yet. Hot start over wood 3 cuts, same 7" round sycamore, ran a 7.15 for a stock year 1983 49cc saw. The other test above were run with my woods ported 066.