Really bad chatter and CSM won't cut UNLESS I seesaw

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Running Granberg Alaskan/3120XP/56" bar/aux oiler/and freshly sharpened chain done with Oregon bench grinder. 10 deg top plate and .025 raker depth.

On wider logs (36+) the saw will not cut unless I seesaw it back and forth. If I try to maintain a constant angle with the mill, it acts as if the chain isn't even touching the wood as it rotates. If I didn't know better, I'd think the bar was shaped like a banana and only the chain nearest and furthest from the powerhead was making contact with the wood as it cuts.

I saw a video posted in the Tips and Tricks thread of a guy casually milling a log, using a hand winch, and the saw is just smoothly going along with little or no effort from him. Saw another pict of a guy sitting in his chair while the saw cut by itself. I don't need mine to work quite that well, but it sure would be nice to not be exhausted after 2 cuts.

I've tried new chains, flipping the bar, getting pissed, being patient, swearing and not swearing, and nothing seems to fix this problem. I'd appreciate any help or input.
 
H
Running Granberg Alaskan/3120XP/56" bar/aux oiler/and freshly sharpened chain done with Oregon bench grinder. 10 deg top plate and .025 raker depth.

On wider logs (36+) the saw will not cut unless I seesaw it back and forth. If I try to maintain a constant angle with the mill, it acts as if the chain isn't even touching the wood as it rotates. If I didn't know better, I'd think the bar was shaped like a banana and only the chain nearest and furthest from the powerhead was making contact with the wood as it cuts.

I saw a video posted in the Tips and Tricks thread of a guy casually milling a log, using a hand winch, and the saw is just smoothly going along with little or no effort from him. Saw another pict of a guy sitting in his chair while the saw cut by itself. I don't need mine to work quite that well, but it sure would be nice to not be exhausted after 2 cuts.

I've tried new chains, flipping the bar, getting pissed, being patient, swearing and not swearing, and nothing seems to fix this problem. I'd appreciate any help or input.
How do the bar rails look? Could have a bur somewhere or the rales could be uneven. I would start there
 
yeah, you should finite not have to seesaw - in fact you should never seesaw if you want a good finish,
lets see the bar rails - are they even, have they got burs,
The lets closeup side on view of a couple of chain cutters.
 
I haven't taken the picts of the bar and chain yet but I did take a video from Saturday. My hope is that just seeing how the saw reacts will help you guys perhaps diagnose my issues.
It's a freshly sharpened chain. One caveat here is that even though I'm making a cross cut, I'm using a ripping chain. I don't own 168DL cross cut chain. It makes no difference for the problem I'm having because this happens whether ripping or cross cutting.

The saw will not cut when holding a steady angle while at the same time trying to cut the entire width of the log. It doesn't matter how hard I push on the mill. It will not cut like this. The thing that really frustrates me is that the middle of the bar is about 1/2" wider than the two ends, but the bar acts like its 1/2" narrower in the middle; if that makes any sense. I inspected the bar and there seems to be minimal wear.

Everything on the CSM is square and tight. The bar is parallel with the guide rails. I'm running a Forester bar and ripping chain if that matters.
 
The video shows classic behaviour of the rakers being too high so we need to see those side on pics of a couple of your cutters, especially the rakers
The rakers are the backstop that prevents the chain becoming too "grabby" but the rakers also penetrate slightly into the wood during the cutting process and is part of efficient cutter acton.
When you see-saw the saw there's reduced contact with the wood so a fewer rakers are in contact with the wood so they can penetrate enough into the wood so teh chain can cut.
When you fully load up the chain straight across the log the high rakers prevent the cutters from taking a bite
I doesn't matter how much much you sharpen the cutters if the rakers are too high.
 
Definitely looks like the depth gauges aren't set correctly. Your chips look awfully small. I had the same problem with a chain that I had sharpened by an online chain sharpening shop that I tried. MS660 with a 32" bar and I had to rock it to cut a piece of willow which should've cut easily.
Good luck!
 
I’ve been setting them to .025 using a feeler gauge, but just received the DAF in the mail today so I’m going to go back and review the threads that show how to sharpen based on angle (progressive something or other?).
B9A7E618-C6D3-49C7-AD6C-66C43E4B5EBA.jpeg
 

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If I can get this saw cutting like it should , I’ll end up dancing in the streets (or woods)!
 
Those rakers and cutter don't look that bad to me.
They work to have a raker angle of about 6º , which is fair enough.
That makes the horizontal length of the pink box about 10x the height of the box (or depth of the rakers)
The 6º is the darker red line relative to the top of the box.
The only thing I would suggest is to clean out your gullets.
Cutter.jpg
One thing that I don't get is the chatter. Unless the rakers are super low then that's not rakers.
Is the bar parallel top the mill rails all the way along.
Also is the bar coplanar to the rails ie front of bar is same depth below the mill rails as the back of the bar?.

I notice you are cutting cookies - does it do the same thing when milling a long along the grain?
 
I’ve been setting them to .025 using a feeler gauge, but just received the DAF in the mail today so I’m going to go back and review the threads that show how to sharpen based on angle (progressive something or other?).
I'd be interested to know what your DAF measures those rakers at... They look around 5° to me.
Make sure you have the area of the bar you're measuring at 0° to start with & move the chain so you measure at the same spot each time.
How tight do you run the chain? Those drive links look quite worn towards the back given how much of the cutter still remains. If the cutters are rocking back excessively due to a loose chain it also effectively raises the raker slightly more
 
Blowing up the second picture, the one that is kind of looking down at the top of the chain, I think I see some 'glint' at the front edge of the cutters. Could be that your chain is not completely sharpened; BobL, please look at that.
 
Currently at work but I wanted to throw in this comment. The chatter I mentioned earlier only happened in the video for a brief moment and even then wasn't bad compared to other times. Sometimes when I put a freshly sharpened chain on (and not just the 56" bar but also the 36" bar) the saw doesn't simply chatter on the first cut, it practically bucks like a bucking bronco. But it only does that for the first cut (5-10 min). After that it calms down and cuts nicely (the 36" bar, not the 56").

I'll continue reading through the responses a little later. Thanks for all your input so far!
 
Blowing up the second picture, the one that is kind of looking down at the top of the chain, I think I see some 'glint' at the front edge of the cutters. Could be that your chain is not completely sharpened; BobL, please look at that.
Yep I agree. Well spotted
There should be ZERO glint along the font edge of that cutter
Screen Shot 2021-05-18 at 9.18.40 pm.png
 
Those rakers and cutter don't look that bad to me.
They work to have a raker angle of about 6º , which is fair enough.
That makes the horizontal length of the pink box about 10x the height of the box (or depth of the rakers)
The 6º is the darker red line relative to the top of the box.
The only thing I would suggest is to clean out your gullets.
View attachment 907535
One thing that I don't get is the chatter. Unless the rakers are super low then that's not rakers.
Is the bar parallel top the mill rails all the way along.
Also is the bar coplanar to the rails ie front of bar is same depth below the mill rails as the back of the bar?.

I notice you are cutting cookies - does it do the same thing when milling a long along the grain?
Yes, bar is parallel and co-planer. Yes it does the same thing when milling along the grain. Trying to rip a 48” log is no fun.
 
I'd be interested to know what your DAF measures those rakers at... They look around 5° to me.
Make sure you have the area of the bar you're measuring at 0° to start with & move the chain so you measure at the same spot each time.
How tight do you run the chain? Those drive links look quite worn towards the back given how much of the cutter still remains. If the cutters are rocking back excessively due to a loose chain it also effectively raises the raker slightly more
I've not measured the angles yet.
As far as the tension on the chain: adjusting the tension on the 56" bar has always been a bit of a guessing game for me. I basically tighten it to where it becomes a little difficult to advance the chain by hand. Even at that point the chain still sags in the middle when pulling down on it mid-way down the underside of the bar.
 
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