Firewood on a Hakki Pilkie 1x37

[barbender]

 Jim, are you intentionally bumping the log a bit on the feed to get through it, or is the saw leaving the offset marks on its own? Are you sure every tooth is still sharp on your chain? My processor was doing this the other night, and only a couple of teeth on one side were dull. I must've hit some dirt. The saw was still throwing nice big chips, and cutting great, but it would still hang up every time it got a little over halfway through the cut. With the yellow painted harvester bar, I can see the point where it is rubbing on the log because it leaves yellow paint there. That would be on the side closest to the saw. Maybe try making a streak with a grease marker on each side and you can see if yours is rubbing somewhere.

[leeroyjd]

@jimbarry
I'm running a Dyna for a friend-same model as @barbender so this may not help.
Owner was just telling me yesterday about very same issue that started on machines 3rd year, maybe 400 cords or so.
He had tried new bars, chains, checking and changing reliefs on bar drop and (I think) chain speed.
 He finally found the relief valve for the splitter was causing the issue.
The hydraulics apparantly run through this valve first, so any issue there will cause issues "down stream".
 Again, maybe yours is set up differently, but I wanted to bring it to your attention.

[jimbarry]

@jimbarry
I'm running a Dyna for a friend-same model as @barbender so this may not help.
Owner was just telling me yesterday about very same issue that started on machines 3rd year, maybe 400 cords or so.
He had tried new bars, chains, checking and changing reliefs on bar drop and (I think) chain speed.
He finally found the relief valve for the splitter was causing the issue.
The hydraulics apparantly run through this valve first, so any issue there will cause issues "down stream".
Again, maybe yours is set up differently, but I wanted to bring it to your attention.

Thanks, I'll look into that.

[jimbarry]

Chain still turning but not cutting?

Chain turning ok, it just will not proceed through the cut.

Jim, are you intentionally bumping the log a bit on the feed to get through it, or is the saw leaving the offset marks on its own? Are you sure every tooth is still sharp on your chain? My processor was doing this the other night, and only a couple of teeth on one side were dull. I must've hit some dirt. The saw was still throwing nice big chips, and cutting great, but it would still hang up every time it got a little over halfway through the cut. With the yellow painted harvester bar, I can see the point where it is rubbing on the log because it leaves yellow paint there. That would be on the side closest to the saw. Maybe try making a streak with a grease marker on each side and you can see if yours is rubbing somewhere.

@barbender Same as this video I posted 7 months ago.
20220821 Hakki Pilke Easy37 cutting bar problem - YouTube
I checked the chain, no issues. I'll see what I can do about seeing whether it rubs or not.

[Hilltop366]

I remember that video.

I think I would make some pointers out of small metal rods or coat hangers ground to a fine point and put them from a solid place to the log and conveyer so that the points line up perfectly and watch them to see if anything moves during the cut. A dial indicator would work to if you have one.

If all is good there I would turn my attention to the saw pivot and figure out a way to check if the bar is running evenly through the travel or has play in any of the positions, a tiny bit of play at the pivot will be amplified as you go down the bar.

As I type this I got to thinking how I had to shim my chainsaw mill bar to make it coplanar with the bed of the mill. Even though it travelled parallel to the bed it had a slight tip up on the leading edge causing it to rise in the cut.

 With the chain removed take 2 straight edge bars (carpenter levels would work) and fasten one that stays the same distance from the bar through it's travel and the put the other on the bar and measure for a difference from one end to the other on the straightedges. If they are out a little bit it would cut drifting slightly to one side and cause it to bind and stall leaving those ridges. 

[jimbarry]

I remember that video.

I think I would make some pointers out of small metal rods or coat hangers ground to a fine point and put them from a solid place to the log and conveyer so that the points line up perfectly and watch them to see if anything moves during the cut. A dial indicator would work to if you have one.

If all is good there I would turn my attention to the saw pivot and figure out a way to check if the bar is running evenly through the travel or has play in any of the positions, a tiny bit of play at the pivot will be amplified as you go down the bar.

As I type this I got to thinking how I had to shim my chainsaw mill bar to make it coplanar with the bed of the mill. Even though it travelled parallel to the bed it had a slight tip up on the leading edge causing it to rise in the cut.

With the chain removed take 2 straight edge bars (carpenter levels would work) and fasten one that stays the same distance from the bar through it's travel and the put the other on the bar and measure for a difference from one end to the other on the straightedges. If they are out a little bit it would cut drifting slightly to one side and cause it to bind and stall leaving those ridges.

Good points. I've often looked at a cut and said to myself, that blade is not going down straight. I did have the pivot off earlier this year when I replaced all the bearing. Replaced all of them and a new sprocket to try and resolve this issue. Didn't work. 
I will also say that this problem is random. On the same log the first cut could be ok. The next one or two could be difficult. Then one ok and the next one difficult. The next log, all cuts could be ok. Then the following log could be all difficult. Or some, or now. Like I said, random.

[Hilltop366]

If the log/conveyer is not moving I would look at being out of coplanar. Just like adjusting the blade guides when a band saw mill blade is not parallel with the deck.

With the "out of coplanar" idea everything will look fine to the eye but the two straight edges would amplify it enough to measure.

If it was out it would get worse as the bar gets closer to horizontal and as the bar wears, it would also cause the bar to wear out unevenly and faster. I would suspect that a harder wood or harder spot in a log and grain around a knot etc. would change how it acts too.

 I can't see the entire bar mount in the video but my guess is that the left side of the mount would be low. 

[barbender]

 Leeroy, that is good to know.

 Jim, that is really frustrating. I don't have any more ideas than what everyone has put out there so far. 

 A pressure guage plumbed to the saw feed cylinder would let you know if it was getting adequate pressure or if something was amiss there.

[doc henderson]

seems like a first cut goes ok.  in the problem cuts, it stick, but a release and abrupt engaging of the control gets you a little jump at a time.  I wonder if the pressure is low like the valve is bypassing at a low pressure.  could be stuff in the valve letting it bypass, but build pressure when you let off and hit it again.  maybe a pressure gauge.

[Hilltop366]

I can't see the entire bar mount in the video but my guess is that the left side of the mount would be low. 

I'll retract that after looking at the picture again I really can't tell the direction of those groves in the end of the log.

[barbender]

The problem with a mechanical bar is that they can't deal with any play or a chain that cuts a little to the side. A handheld chainsaw will cut curves, a mechanical saw can't do that because they don't have any give.

[doc henderson]

can you or have you tried letting the bar out of the cut, and cutting again?  that might confirm the curve theory.  it might then cut and edge and make it through the cut.  not that you want to have to recut each log.  I am surprised that the HP tech. folks cannot watch the video and help out.  I would think they would not want this info out about their product and no one is helping you out.  I do not know the mechanical details of this machine.  

[doc henderson]

I watched the first part of the video again.  their is a drop in the pitch of the cutting noise.  is that the cutting by the chain or the speed of the pump.  of course it goes back up when the bar stops advancing.  

[doc henderson]

In other words, it seems if it is in a jam, the chain speed would slow or stop, or the pump would be applying full pressure and making a heard working noise trying to plow through the log.  I assume the down pressure is hydraulic.  

[barbender]

Doc, what happens with a mechanical bar saw is if something is off, the bar will press into the kerf so hard that it stops the bar. The chain still spins completely free, it is under no load at all. 

[jimbarry]

can you or have you tried letting the bar out of the cut, and cutting again?  

Yes, I can. Sometimes successful. Sometimes not.

that might confirm the curve theory.  it might then cut and edge and make it through the cut.  not that you want to have to recut each log.

Sometimes 4-5 recuts required. Not moving the log, cutting down into the same kerf. 

I am surprised that the HP tech. folks cannot watch the video and help out.  

I've tried several times over the years, they never reply. Their response is contact your dealer. Well, the dealer says to bring it in and it is a 6 hour round trip to drop it off, and another 6 hours to go pick it up. Even when I asked a question on this same issue of a video they posted on their own YouTube channel a few days ago. 

I would think they would not want this info out about their product and no one is helping you out.  I do not know the mechanical details of this machine.  

[doc henderson]

you say a mechanical bar.  is it a hydraulic ram pushing it?  what do you mean mechanical bar.  I told you I do not know the machine.  it seems if the bar is pushing down hard and cannot go further, that it might stop the chain or at leat make a high pressure sound.  is it hydraulic?  those are the saw motors I have seen before.  do you feel the jam is in the mechanism?  that I guess would explain the chain turning freely, and the bar not advancing.  does it appear cockeyed in the cut?  is there a curve to the end?  trying to help.

[jimbarry]

Doc, there are two versions for the chainsaw blade motion activation. One, the bar comes down into the cut using the operator's arm pulling down on a bar that is mechanically attached to the chainsaw blade. Example;


 

The other (my machine) the chainsaw blade is hydraulically controlled from the joystick, 



 

whereby a small hydraulic piston (picture here highlights the grease zerk at the top of the piston)



 


inside the machine moves the chainsaw blade up and down.

I am not certain, but I think if you pressed too hard, too fast the chain can stall as you'd burn up the belt that drives it. 99.9% of the time the blade stalls in the cut while the chain keeps turning. ON my model the chain runs continually from the time the machine is turned on until its turned off.

Without micrometers etc, I suppose one way to check for a chainsaw blade that is not cutting straight would be to take a 6x6 or 8x8 cant and run it through to see if it stalls. If it does, then check with a framing square.

[doc henderson]

so I wonder if it could be a linkage or a valve that is bypassing.  or else it should pull hard on the motor if it is still tying to push the bar.  sounds more like it just stops trying.

[barbender]

 The relief pressure on the hydraulic feed is very low. It doesn't take much feed pressure to stall the chain when everything is otherwise working correctly.

 Doc, when I use the term "mechanical bar" I mean a bar that is on a processor like this, or like on the logging harvesters. You run into the same type of issues with the barsaw on a $800K Ponsse Scorpion as you do on Jim's little Hakki Pilke. Sometimes you hit something with a few teeth on just one side, and the bar will start hanging mid cut. I've never had it happen in the limited amount of time I've run harvester, but the bearings in the saw motor can go out and cause similar issues. 

 Jim, I'm going to ask the obvious again just trying to check all of the boxes- you have the correct gauge of chain on? My first binding issues when I brought my machine home was due to someone putting .063 gauge, .404 chainsaw chain on the .80 gauge, .404 bar. It wandered in the cut enough apparently to cause the bar to bind. 

 My machine has an adjustable feed pressure, I turned it up and it would then stall the chain, so that wasn't the problem.
It wasn't until I put a new harvester chain on that things worked correctly.

 It's not impossible that you have a feed pressure issue, but the way your cuts are stepped suggests something else.

[doc henderson]

well gents, thanks for letting think along with you.  Jim I hope you get it fixed.

[jimbarry]

...
Jim, I'm going to ask the obvious again just trying to check all of the boxes- you have the correct gauge of chain on? 

Here are the chain and blade we use.


 

 

[doc henderson]

can you safely test each component safely?  like the down pressure of the bar?  it is odd how it jumps a little each time you cycle it to get through the log.  

[jimbarry]

can you safely test each component safely?  like the down pressure of the bar?  it is odd how it jumps a little each time you cycle it to get through the log.  

I tried a while back to test the up and down pressure with no chain on. Nothing scientific, just me holding onto the bar for both directions. Seems to be plenty. The jump marks are a result of bumping the joystick to try and get the blade through the log.
I did put a resharpened chain (I sharpen chains with a oregon bench grinder) on this morning. It's better by about 80%. Still stops mid cut a bit but better than what it was.

[Corley5]

Still sounds like a bar chain issue. It could be a relief valve...  My machine will do the same thing if the bar rails need to be trued, the bar groove is worn too wide, the chain drivers are worn thin, the chain cutters aren't ground equally or one side has hit something or a combination of these things. If it were my machine I'd start with these issues first. A new bar, chain and sprocket and I'd seriously look into converting to wider kerf stuff. At least .375. Are you running semi chisel chain? It's much more forgiving.