Sharpening question - Photos included

[kdxken]

Hello,

I need some help with sharpening, the specifics are listed below and I included photos. Whenever I sharpen a chain it works O.K (not like new) using the bottom of the bar, pitifully using the top. The result seems to be pretty much the same whether I use a bench grinder or hand file.

Anything in the photos indicate what I am doing wrong? Other than poor sharpening, the only thing I can think of is I haven't changed the rim sprocket in a very long time. Any help would be greatly appreciated, it's driving me nuts...


The chain : WoodlandPro 20NK-78 325 pitch, .050 gauge, semi-chisel

Saw:346xp

Sharpener : Northern Tool bench grinder

settings : top plate cutting angle 60, top plate filing angle 35 degrees.

First time sharpened, did not file rakers.

Before filing photo,After filing photo,New chain photo,

After sharpening -Chips from small maple.

View attachment 312801View attachment 312802View attachment 312804View attachment 312805
Video - cutting extremely dry black locust.

00107 - YouTube

 

[mdavlee]

You need more hook on the cutter like the new chain. Then drop the rakers a little bit with a flat file and you should get better results.

 

[kdxken]

You need more hook on the cutter like the new chain. Then drop the rakers a little bit with a flat file and you should get better results.

Thanks for the reply. Would laying the grinding wheel at a more horizontal angle(less steep) work or would I be better off using a hand file?

 

[mdavlee]

I use a file on round chain. Laying the wheel down more should put more hook on it. What angles are you using?

 

[kdxken]

I use a file on round chain. Laying the wheel down more should put more hook on it. What angles are you using?

60=top plate angle 35=vise angle

 

[Trx250r180]

try 25-30 instead of the 35 setting ,also how is your grinding wheel dressed ? it should be half round like shape of a file

 

[mdavlee]

That's about normal. Try to get more hook with the grinder like when filing. You should have 20% of the file above the top plate and 80% under.

 

[kdxken]

try 25-30 instead of the 35 setting ,also how is your grinding wheel dressed ? it should be half round like shape of a file

I pretty much just took the edge of both sides, I'll try re-dressing the wheel. Thanks for the tip...

 

[kdxken]

That's about normal. Try to get more hook with the grinder like when filing. You should have 20% of the file above the top plate and 80% under.

Makes sense, I'll try that as well. I don't think the wheel hit much of the top plate at all..

 

[kdxken]

Another quick question: I have a few other chains with bumpers, when the rakers get filed down to the bumpers is it O.K to file the bumpers as well?

 

[mdavlee]

Yeah knock the bumpers on down so the chain can get a bite.

 

[1270d]

Yes its OK. If your not real experienced at filing, it wouldnt hurt to get a raker gauge to help keep them tailored to the cutters. This will help keep everything smooth

 

[rwoods]

try 25-30 instead of the 35 setting ,also how is your grinding wheel dressed ? it should be half round like shape of a file

After you get the wheel dressed, then make sure your depth is not too deep - don't grind past the curvature of the wheel or you'll just flatten the tooth out again. Probably oblivious but it wasn't to me at first. Ron

 

[Philbert]

It is always hard to judge based on a photo, but I agree with the post above: it looks like you are driving the wheel down into the gullet, instead of sharpening the top plate edge (see the attached sketch - round file held with 1/5 or 20% above the top plate, and half round profile of grinding wheel in same position).

Photo 3 looks more like full chisel chain (pointy, leading corner)? Are these the same chain?

- I recommend using a 30 degree vise angle, unless you are cutting into really hard wood or frozen wood.
- I recommend a 55 or 60 degree grinder head tilt.
- If you are using full chisel chain, you can tilt your vise +10/-10 degrees (if the NT allows it), otherwise 0 degrees for semi-chisel.

- Dress the edge of your grinding wheel half round, and don't take it deeper than the sketch shows (set the stop screw). Are both the top and side plate cutting edges getting cleanly ground? Are they sharp? Keep checking back at your piece of new chain: do the ones you just ground look like these? If not, try to figure out why.

- Afterwards, you can move the stop on the chain positioning vise back 1/2 a turn, and lower the grinding head another 1/2 a turn or so, and go back and clean out your gullets without touching the two cutting edges.

Philbert

 

[kdxken]

It is always hard to judge based on a photo, but I agree with the post above: it looks like you are driving the wheel down into the gullet, instead of sharpening the top plate edge (see the attached sketch - round file held with 1/5 or 20% above the top plate, and half round profile of grinding wheel in same position).

Photo 3 looks more like full chisel chain (pointy, leading corner)? Are these the same chain?

- I recommend using a 30 degree vise angle, unless you are cutting into really hard wood or frozen wood.
- I recommend a 55 or 60 degree grinder head tilt.
- If you are using full chisel chain, you can tilt your vise +10/-10 degrees (if the NT allows it), otherwise 0 degrees for semi-chisel.

- Dress the edge of your grinding wheel half round, and don't take it deeper than the sketch shows (set the stop screw). Are both the top and side plate cutting edges getting cleanly ground? Are they sharp? Keep checking back at your piece of new chain: do the ones you just ground look like these? If not, try to figure out why.

- Afterwards, you can move the stop on the chain positioning vise back 1/2 a turn, and lower the grinding head another 1/2 a turn or so, and go back and clean out your gullets without touching the two cutting edges.

Philbert

Awesome...much appreciated

 

[kdxken]

Phibert,

Same model chain, could be my photography. Reading your description I'm sure I wasn't high enough, I would guess I hardly touched the top plate edge. Thanks again for the diagram, very helpful...

 

[madhatte]

Remember that each chain is different, and these adjustments will need to be made on each one. Also, note the downward slope from the front of the cutter to the rear -- the raker will need to come down proportional to that slope through the chain's life. One fixed depth gauge will not cover this change. You'll want to use a progressive gauge like the Carlton File-O-Plate to cover the lifetime of the chain.

 

[JakeG]

Remember that each chain is different, and these adjustments will need to be made on each one. Also, note the downward slope from the front of the cutter to the rear -- the raker will need to come down proportional to that slope through the chain's life. One fixed depth gauge will not cover this change. You'll want to use a progressive gauge like the Carlton File-O-Plate to cover the lifetime of the chain.

kdxken, the file-o-plate is a simple, useful product... check out their youtube video for it: CARLTON® File-O-Plate - YouTube

 

[TheJollyLogger]

For the best, consistent results....

Chainsaw sharpening with an angle grinder - YouTube

 

[Red Amor]

be very mindful of the depth and shape you set the rackers at
If your too deep it can make a saw jump n buck about in the cut particularly in dry hard wood
the saw more likely to kick back
and a powerful saw will be hard to hang onto and ever more dangerous
all this will also streeeech the chain and in the extreem continued use cause breakage




mind how ya go mate