MF-124 baler-shear knife servicing

[flusher]

I fired up the baler yesterday. Getting jams in the bale chamber (plunger stalls, slip clutch slips). Looks like the shear knives need sharping or replacement. This is my first whack at that job.

Looks like the plunger knife has gouges on the lower end.

Stationary knife on the bale chamber wall looks a little ragged also

Bale chamber appears to be OK. Restrictors are free of clogs. Don't know if the wear on the ramps is normal or excessive. Chamber walls don't look as shiny as I would expect. Wonder if this is a problem.

Removing the shear knives looks like a bear--I haven't figured out the easy way (if there is one) to reach and unscrew the three screws (5/16" Allen head type) on each knife. I could remove the two rails on the top of the packer chamber to reach the screws on the two knifes. Is this the usual way to handle this access problem?

The service manual says to detach the plunger drive rod from the crank arm on the main gearbox. Do the pros bother with this step? I can stop the flywheel from turning by jamming a 2x4 wedge between the flywheel and the housing to keep the plunger from moving. OK, or a no-no?

 

[zzvyb6]

Removing the plunger may be the best way to get the job done (or at least 1/2 of it). They don't look too bad, actually. It could also be a spacing problem. Spacing between knives should be about 1/16" or slightly less. And I mean a dynamic spacing problem too: The plunger has worn lateral control and is getting shoved over by the hay charge. Also check your feeder to see if it needs to be adjusted to move hay farther into the chamber. Of course, damp hay or hay above 18% moisture will cause this too.

 

[flusher]

Removing the plunger may be the best way to get the job done (or at least 1/2 of it). They don't look too bad, actually. It could also be a spacing problem. Spacing between knives should be about 1/16" or slightly less. And I mean a dynamic spacing problem too: The plunger has worn lateral control and is getting shoved over by the hay charge. Also check your feeder to see if it needs to be adjusted to move hay farther into the chamber. Of course, damp hay or hay above 18% moisture will cause this too.

Thanks for the feedback.
I'll check the gap between the blades before removing/replacing them.
I adjusted the windguard to the position for heavy crops.
Didn't make any adjustments on the packer fingers.
The windrow did get rained on the previous night but the accumulated rainfall was too small to register on my rain gauge. But it probably was damp.
I figure if I disconnect the plunger drive shaft from the gearbox crank (pretty easy-two bolts to remove), I can move the plunger by hand to check alignment, determine if there's slop in the plunger guides, position the plunger to measure the gap between the blades and for blade replacement. Safer that way also.

I have a pair of used blades, but the gouges in the cutting edges probably are too deep to just grind away.

Looks like the stationary blade has be used twice, flipped between uses. Also looks like the gouges on the two blades line up pretty well, which I suppose is what you would expect.

I considered trying to weld fillers in the gouges and then grind the edge. But I suppose the heat treatment on the blade would be messed up that way.

So far my Web search has not yielded a supplier for the blades. Unless I can find a second source for those blades, looks like I'll have to pay my local MF dealer a visit and place an order. Expecting sticker shock doing it that way.

 

[zzvyb6]

Funny how those blades look like they could interchange with JD blades. Your used ones are in better shape than my current, in-use ones. Sharpen them and stuff them in...

 

[flusher]

Funny how those blades look like they could interchange with JD blades. Your used ones are in better shape than my current, in-use ones. Sharpen them and stuff them in...

Interesting. I suppose all the small square (14"x18") balers have a lot of design details in common, including these blades. Wonder if the holes would line up on MF and JD blades. If so, that would surprise the heck out of me.

Also find your observation regarding your blades vs my spare blades interesting. Looks like a few gouges don't cause baler performance to deteriorate that much. Nothing like a forgiving machine--very much appreciated by a haying newby like myself.

I'll try your hollow grinding method on the spare blades using my table saw and see what happens.

 

[flusher]

Forgot to mention that I plan to check the slip clutch pretty thoroughly. I slipped it twice already and don't know how many times the previous owner slipped it before I bought the baler.

The slip clutch is pretty simple. Didn't realize it has a sprag clutch (item #12) as part of the slip clutch assembly until I checked ops manual and looked at this drawing

Does your 14T have a sprag?

 

[hudsonfarm]

Dude give me a call 302-242 0995 if you have a verizon cell. I probably can point you in the right direction on that baler. it is probably not the knives. normally they will shear the pin on the fly wheel when the get wonky. let me ask you a question did you remove the 3 3/8 bolts on the clutch shield to grease that universal and slip clutch?

 

[flusher]

Dude give me a call 302-242 0995 if you have a verizon cell. I probably can point you in the right direction on that baler. it is probably not the knives. normally they will shear the pin on the fly wheel when the get wonky. let me ask you a question did you remove the 3 3/8 bolts on the clutch shield to grease that universal and slip clutch?

Thanks for the offer. I'm AT&T.

I unscrewed those 3 bolts and removed the clutch shield to check the slip clutch. The U-joint was greased pretty good. I did not repack the sprag clutch with lithium grease since it looked OK. Maybe I should check this again.

I checked the shear pins on the flywheel and on the packer arm after the plunger stalls. Both pins are OK.

 

[hudsonfarm]

call me any how I would bet the farm I can fix the problem

 

[hudsonfarm]

if you tightened those 3 bolts like yo normally would a 3/8ths bolt if you look at the design of the clutch you will notice those bolts tightened to what you feel is enough will actually spread the clutch apart. you can tighten the springs for the clutch until they shear and the clutch will not engage fully. When the left knotter is breaking about every other bale give me a shout I am fortunate enough to live about 50 miles from the massey mechanic who was sent around to trouble shoot the problems on the 24-28 series.