Chain Saw Sharpening

[charlz]

I have been using the harbor freight sharpener for a couple of years and love it for sharpening the teeth. Unfortunately it is not so handy for setting the depth. I started tinkering and found that the depth is every bit as important. That got me thinking.

I live in a pine forest and pine or aspen is all that I ever cut. Could I get away with dropping the depth deeper then the manufacture recommends since I am only cutting soft wood? I am tempted to just try it on my old mcculloch, but I figured I would put the question out there first.

Not sure what you mean by setting the depth? As you sharpen the chain you actually make the cutting teeth shorter (height and length). You adjust for the change in height by taking a flat file to the rakers, which are the teeth right in front of the cutting teeth. If you get these too low the cutting teeth can take too large a bite/feed too fast which will cause your saw to bog and possibly the chain to hang a lot.

 

[2manyrocks]

File sharpening works fine for me. I use a guide as was posted earlier.

 

[Bedlam]

I think by depth they mean the raker height?

 

[Raw Dodge]

I have the northern tool grinder.I have 4 chain saws,and a pole saw,dad has 3 saws.I keep them all sharp and ready with the grinder.I got it for 89.95,as a xmas gift,also got better grinding wheels from baileys,this thing works great.Its one of the best gifts my better half has gotten me.

 

[Colorado Michael]

That is correct. I am referring to the raker height. I think I will be able to cut pine faster by taking a little more off the raker.

Arrow and Charlz, thank you for the feedback. I will try with a couple of different chains with modified raker heights and see if the saw is slowing down too much.

 

[rus_geek]

I think Michael would be fine to take his rakers down "lower than spec" when only cutting soft wood. I've actually used a chain with no rakers. Easy to overload the saw on hardwood, but flies through the soft stuff. It actually made strips in willow rather than the usual chips.

-r-

 

[Bedlam]

May I ask what tool people use for the rakers. I carefully use the angle grinder on mine but its sort of a rough job.

 

[turnkey4099]

May I ask what tool people use for the rakers. I carefully use the angle grinder on mine but its sort of a rough job.

There are very cheap raker file guides available at any shop sellign saws. A buck or two. You lay it on the teeth, the raker sticks through a slot and you file with 'safe edge' flat file until it won't bite any more. They come in various depths.

Standard depth is .025, soft wood will take a .030 (I use that even on hardwood). Next time I am at a shop I will be looking to see if they have an .035.

I am playing with my Harbor Freight grinder to do the rakers. Works fine but is a bit of a 'fiddle around' to get it set the proper depth.

Harry K

 

[Youare]

I have been sharpening my saw chains for 30+ years and lately most of the time I can get them to cut pretty good. Not so when I first tried and for quite a while after.

The top angle is the most critical issue other than getting all the dull out of the tooth. Most of the time attention is focused on the point of the tooth and not the other side, or open side, of the top of the tooth.

Look closely at the tooth profile of a new chain and try to keep the top angle and side profiles the same. There are two angles to the top on the tooth, one you see looking down at the top of the guide bar the other is what you see when looking at the side of the guide bar.

When looking at the top of the guide bar the alternating angles of the top of the teeth can range from 25 to 35 degrees. an angle of 30 degrees is fairly standard some chains will have a line scribed on the top of the tooth near the back that matches the angle the cutter was originally sharpened to. (The manufacturer says this mark is to tell you when the chain has reached the end of life.) Keeping this top angle consistent will help keep the saw cutting straight.

The top of the tooth angle looking at the side of the guide bar wants to be fairly blunt, more vertical than horizontal. The more horizontial this angle the thinner and longer the cutting edge is and will dull quicker.

The profile of the side of the tooth will have a slight hook to it, try to keep this profile. More hook affects the angle of the top of the tooth.

The raker in front of the tooth controls the depth of cut and is very important. As the tooth is filed the relationship between the raker and the top of the tooth changes, the tooth becomes lower than the raker. Usually a height difference of .025 ( 25 thousands of an inch) is standard. Those who have what is called a safety chain or low kick-back chain will have another piece in the chain that sits in between the raker and the back of the tooth in front of it. I have filed those down also to make the chain cut right.

The height of the raker will greatly affect how the saw cuts. When the raker is too high it will feel like you have to push the saw through the wood and the saw dust will be little short pieces like dust. When the rakers are too low the chain will grab, bounce, and bog the saw down. The saw dust will be thicker and chunky but still shorter. When the rakes are near the proper height the saw will cut smooth and slightly pull itself into the wood without bouncing. The saw dust will be longer curls.

When trying to "plunge" or bore with a chain saw start with the bottom of the nose of bar and feed the bar in until the round of the nose can not be seen. At this point you can begin to rotate the bar to plunge straighter in, BUT REMEMBER TO KEEP MORE PRESSURE ON THE BOTTOM OF THE BAR. Once you have either come out the other side or have burried the bar at least 3/4 of the way in don't think of cutting with the top of the bar.

If your raker height is too low and you are trying to make a plunge cut it will be uncomfortable and dangerous no matter what you do.

Be safe.

Randy