Critique this ugly chain please

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JeffRH

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This chain needs sharpened. I use a Granberg jig to do it myself, but this season (my second with this jig) I was really disappointed in the results because it seemed like after 5 minutes of cutting it was like I might as well have not sharpened at all.

This is the chain that is on the saw right now and it basically doesn't cut a single thing. I'm 100% sure it's something related to what I'm either doing or not doing while sharpening. I know I've got the angle right, but I think it's the height I have the jig set at that's the problem. There's no curve under the tooth.... the tutorial the jig's directions referenced online says that 1/4 to 1/5 of the file should be above the top of the tooth, which is approximately what I'm doing, but I still don't think it's right.

My typical routine is 10 strokes (one direction) per tooth, which seems to be way more than what most people say you should have to do. This chain has not had the rakers done yet either... I have others where I've taken the rakers down but they still don't seem to work as well as I would expect right after doing that, so I'm sure it's something to do with my sharpening technique.

This is one chain of several, so how would you go about fixing it and bringing it back to something respectable?

Critique away!

IMG_20181019_190955790.jpg
 
File more into the cutter the top cutting edge needs more overhang a husky roller filing guide with the correct size file should get heading in the right direction
 
Thst tooth does not look like it has been sharpened at all. Looks very dull and your file is not low enough.

Set your jig back up and take one or two strokes then look at the underside of the tooth. You should see the new shiny metal where it was filed. You need to make sure that when you file the whole cutting edge of the tooth becomes shiny, all the from the tip to the other side of the tooth.

What angles is your jig set at? I run 25 or 30 degrees for your filing angle, I do not use the side title angle, 0 degrees is fine for most every chain, and make sure the file is low enough and the whole cutting face is getting filed. Then adjust the rakers!!!!!!!! I cannot stress that enough. You should be amazed when done properly.
 
Here is a new tooth from a 3/8 pitch chain. See the hook on the tooth? That's what you are trying to replicate.
20181020_103656.jpg
20181020_104021.jpg
 
I agree with Marshy! I don't do much with files on my chains,--mostly just when away from home.--I use a grinder to lightly touch up the cutters. I can do a quick light touch up quicker than hand file. Also keeps the angles more accurate. thanks; sonny580
 
File more into the cutter the top cutting edge needs more overhang a husky roller filing guide with the correct size file should get heading in the right direction
That's what I thought too - I looked it up on a Stihl file guide and I'm using the right size file for that chain (4.8mm). I got a new one out today and put it in the jig, but it still seems like it's cutting the groove too flat to not allow any hook. It's down as far as it will go, to the point where the file is hitting all the way from the tip of the tooth to the bottom of the curve. I did notice that one one side it's really grinding in there like it's doing some serious filing, but when I switch to the other side it seems like it's gliding more smoothly, so I don't know if each side is being filed the same....

Thst tooth does not look like it has been sharpened at all. Looks very dull and your file is not low enough.

Set your jig back up and take one or two strokes then look at the underside of the tooth. You should see the new shiny metal where it was filed. You need to make sure that when you file the whole cutting edge of the tooth becomes shiny, all the from the tip to the other side of the tooth.

What angles is your jig set at? I run 25 or 30 degrees for your filing angle, I do not use the side title angle, 0 degrees is fine for most every chain, and make sure the file is low enough and the whole cutting face is getting filed. Then adjust the rakers!!!!!!!! I cannot stress that enough. You should be amazed when done properly.

File is as low on the tooth as it can possibly go, and it's the size recommended by Stihl's file guide. Do you think I should choose a smaller one? Depth gauge number is a 2, which corresponds to a 4.88mm file on Stihl's chart. Jig is set for 35 degrees but 0 degrees for the side tilt angle. Should I try 25 or 30 maybe? Checked the rakers today with the guide and they're still low enough, but I have some other chains that will need them taken down. I want to figure out this one first and then I'll get to work on the others once I have a plan that I know works.

I agree with Marshy! I don't do much with files on my chains,--mostly just when away from home.--I use a grinder to lightly touch up the cutters. I can do a quick light touch up quicker than hand file. Also keeps the angles more accurate. thanks; sonny580

Can you (or anyone else) recommend a grinder that won't break the bank? That's what I'd rather do when I'm in the garage, but I don't have one yet.
 
Please show another picture of your cutter. Try to replicate the one I took.

What pitch is your chain?

35 degrees is too steep on my opinion, use 30 degrees.
 
Exactly what was thinking. Maybe .325 pitch chain and using a file for 3/8 pitch chain.

Yep - it's a .325 pitch chain. Depending on what you all think of these just-sharpened pictures from last night I might get a smaller file tomorrow. I thought it seemed big too, but it's the size recommended by the Stihl file guide.
snip1.JPG snip2.JPG
 
Exactly what was thinking. Maybe .325 pitch chain and using a file for 3/8 pitch chain.

Actually I misread this quote here. This is the chart I've been using, so maybe I'm misunderstanding it... It's a .325 chain (depth gauge code 2), and the file used in the above photos was a brand new 4.8mm file fresh from the package. Is that incorrect?
snip3.JPG
 
The very tip of the cutter does most of the work along with the top plate. The side of the tooth just shears the wood chip out. What you need to do is find a file height that brings the new sharp edge all the way along the top plate, you want it to look like a chisel and be sharp like one with a nice sharp corner. The angle you file that at will also set the bevel on the side plate, changing the height of the file changes the angle of the bevel on the top plate and the hook. You want enough hook to make a sharp top plate but too much will make a weak cutting edge on the top plate and your chain will go dull very quickly. Factory specs are just a starting point, you can modify them to suit the wood you are cutting, little less hook for very hard or abrasive wood, little more for soft clean wood. Same with raker height, it sets the size of the bite the cutter takes. Little lower for soft wood, little higher for hard wood.
 
How's this look? Too big of a file? This is the 4.88mm one. I have a smaller 5/32 file that's old, but I tried something out on another chain tonight. The teeth on the other one were REAL bad and filing with the larger one just seemed to make it even duller, so I hit it with the 5/32 to get the general hook shape, and then passed over it about half a dozen times with the larger file to finish up. It seems to have helped a lot with the second chain. Going to be using them a lot this weekend, so I"m curious to see how they go.

IMG_20181023_205034702.jpg
 
3/16 is the file size I always used for .325 chain it's roughly the same as 4.8mm but they're sold as 3/16. The last close up pic you have looks like the tip of the cutter is bent or dinged pretty bad, the very tip (or working corner) is the most important part of the cutter. It does almost all the work and it needs to be as sharp as possible, think of trying to square up a mortise in a piece of furniture with a chisel that has dull and or dinged corners. Won't work, the chisel just won't cut even though the rest of the chisel is sharp the corners just make it want to plow wood and pop out of the cut.

Second thing is to set the rakers properly, Husqvarna makes a very nice little file guide that progressively lowers the rakers in relation to the length of the cutter. Makes for a consistently cutting chain through the whole life of the chain, in fact their roller guide kit is actually pretty nice. They sell them for each different chain size and they come with the correct file, file guides, and a raker file. I bought one just for the raker height gauge.
 
How's this look? Too big of a file? This is the 4.88mm one. I have a smaller 5/32 file that's old, but I tried something out on another chain tonight. The teeth on the other one were REAL bad and filing with the larger one just seemed to make it even duller, so I hit it with the 5/32 to get the general hook shape, and then passed over it about half a dozen times with the larger file to finish up. It seems to have helped a lot with the second chain. Going to be using them a lot this weekend, so I"m curious to see how they go.

View attachment 681322
Too large or not set low enough. Only about 10% of the file should be above the tooth. Use the 5/32 file and show us how it looks after sharpening.
 
How's this look? Too big of a file? This is the 4.88mm one. I have a smaller 5/32 file that's old, but I tried something out on another chain tonight. The teeth on the other one were REAL bad and filing with the larger one just seemed to make it even duller, so I hit it with the 5/32 to get the general hook shape, and then passed over it about half a dozen times with the larger file to finish up. It seems to have helped a lot with the second chain. Going to be using them a lot this weekend, so I"m curious to see how they go.

View attachment 681322
That tooth will not be any good till it is filed back past that taper on the corner
 
Can’t really tell from the pics, but some of tops of those teeth almost look like they’ve been rocked ie: gotten into the ground and boogered up.
If that’s the case, the chain will never cut correctly until it’s filed back enough to remove boogered up area.
Also, in some of the pics it looks like you’re filing too high not taking enough of the throat area (gullet) but in some of the pics it looks like you’re filing way too deep (too much gullet)
It’s just hard to really tell from the pics.
 
That cutter will need about 40 percent removed to get behind the worst of the damage. Roughly above where the colors ( in this photo) first looks to change from pink to brown.

I tried to mark and repost the image, but keep getting an error message.
Sorry but Not going to allow scripts to run willy-nilly from any site, just to try getting an image uploaded.
 

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