newbie - sharpening angle

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faciette

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I try to file a dolmar 486 chain (33SL I think). The sharpening angle is supposed to be 25 degrees horizontal and 10 degrees vertical. However, when I put the guide on a new chain, the angle looks like 30 degrees. I don't understand. Is is normal to wear the chain under the file ? I use the right file (11/64").
 
I usually grind to 30 degrees also. It's a little slow on a new chain that is at 25 or 35, but trying to keep up with all the different angles is maddening and makes very little difference in my experience.
 
LOL!!!

I have filed on Stihl chains so much that all of 'em end up 30 degrees regardless of who made them, or if I try not to.
Carlton/Bailys chain cuts great at 30 degrees BTW.;)

Oregon chain with the 10 degree drop is a PITA when ya forget.

Just run it 30 and try to remember the drop angle...mostly.

Stay safe!
Dingeryote
 
Keep in mind that the 10 degree drop angle of the file will slightly change the top plate angle relative to the horizontal angle of the file. Dropping the file at the heel of the top plate lets the edge of the top plate extend over the top of the file more at the heel than at the point, which also produces the 45 degree top edge slant at the heel and the 15 degree slant at the point.
 
Keep in mind that the 10 degree drop angle of the file will slightly change the top plate angle relative to the horizontal angle of the file. Dropping the file at the heel of the top plate lets the edge of the top plate extend over the top of the file more at the heel than at the point, which also produces the 45 degree top edge slant at the heel and the 15 degree slant at the point.

You've lost me and I sell and sharpen lots of chains?

You'll find very little difference if you sharpen at 10° or not. I've done comparisons between 0° and 10° and there is only a very slight difference in cutting speed but not worth the pain of trying to get every tooth the same angle with a file. Stick with 0° if in doubt as the human eye handles that angle easily.
 
Keep in mind that the 10 degree drop angle of the file will slightly change the top plate angle relative to the horizontal angle of the file. Dropping the file at the heel of the top plate lets the edge of the top plate extend over the top of the file more at the heel than at the point, which also produces the 45 degree top edge slant at the heel and the 15 degree slant at the point.

+ 1

Yes, the 10 deg. file up angle is supposed to match the top plate tilt angle to get a consistent cutting edge thickness across the whole of the top plate. Carlton is flat topped while a lot of others dip. The difference is small though and likely not noticeable unless you were putting a stop watch to it. Filing on the bar is a bit like shooting moving targets and you dont hit where you aim anyway!
 
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It will help if we all use the same language.

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When using a file guide angle (as per diagram) on a flat topped cutter, the outside edge will have more top plate cutting angle (NB that is different to Top plate filing angle) or hook (and will cut more) but go blunt quicker, whereas the inside edge just above the link will have less hook and cut less but last longer.

If you use a zero file guide angle on a sloped top cutter the reverse happen.

Ideally you want to maximize your cutting ability across the whole cutter so zero degrees on a flat top cutter gives an consistent top plate cutting angle across the cutter, and 10º is typically used on sloping cutters. If you don't do this the chain is not cutting optimally and you either push end up pushing saw unnecessarily, or sharpen more often than you need to because you are really (eg 10º) only using half the cutter.
 
It will help if we all use the same language.

attachment.php


When using a file guide angle (as per diagram) on a flat topped cutter, the outside edge will have more top plate cutting angle (NB that is different to Top plate filing angle) or hook (and will cut more) but go blunt quicker, whereas the inside edge just above the link will have less hook and cut less but last longer.

If you use a zero file guide angle on a sloped top cutter the reverse happen.

Ideally you want to maximize your cutting ability across the whole cutter so zero degrees on a flat top cutter gives an consistent top plate cutting angle across the cutter, and 10º is typically used on sloping cutters. If you don't do this the chain is not cutting optimally and you either push end up pushing saw unnecessarily, or sharpen more often than you need to because you are really (eg 10º) only using half the cutter.

+1 :agree2:

....and if you look closely at what you are doing, you don't have to think about the up angle (vs none), you will see when the relation between the file and the top-plate is right.
 
Or you buy a decent grinder :) Problem solved.

To file a chain properly is a bit of an art that I haven't, never will, and don't have the time to master! Touching up a chain is fine but I just swap blunt chains out and sharpen them when I get home.
 
It will help if we all use the same language.

attachment.php


When using a file guide angle (as per diagram) on a flat topped cutter, the outside edge will have more top plate cutting angle (NB that is different to Top plate filing angle) or hook (and will cut more) but go blunt quicker, whereas the inside edge just above the link will have less hook and cut less but last longer.

If you use a zero file guide angle on a sloped top cutter the reverse happen.

Ideally you want to maximize your cutting ability across the whole cutter so zero degrees on a flat top cutter gives an consistent top plate cutting angle across the cutter, and 10º is typically used on sloping cutters. If you don't do this the chain is not cutting optimally and you either push end up pushing saw unnecessarily, or sharpen more often than you need to because you are really (eg 10º) only using half the cutter.

Read the instructions carefully and they tell you that if your using a 'fits on the file' file guide on Oregon chain to forget the 10° angle and file it flat!

Or just buy Stihl chain and file it flat all the time:cheers:
 
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