Drum help ...again

  • Thread starter Greenhorn
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I thought I had my old drum chipper figured out and then its starts acting up going into the spring!

I recently replaced cutter bar and knives and got factory spec. clearances set upon re-installation.

Smooth for awhile and then outta the blue the thing wont eat material over 2" anymore. It chews out a little arc and then spits the piece back. Tolerances have not changed upon visual inspection.

Can thousands of an inch change the feeding of these old dinosaurs? I cant figure out it out - surely the line clearance chippers arent looked after any closer than I maintain mine.

Thanks for any help, sources for help on these things arent as plentiful as they once were. Getting a nice shiny Morbark one day....
  • Thread Starter Thread Starter
  • #5
hmmm... too close, possible I guess, not leaving enough material to drag the rest through.

Trial and error sucks - so many big bolts to loosen and re-torque! Fun weekend ahead.
check the drum bearings for slop to. pry up with a bar to see if theres movement
I got nothing to add, its all been said already.

Base plate/knive loose or worked its way out, loose bearings, knives worked out a bit.

Say, did you check the torque after chipping a few branches?
Greenhorn, I've changed blades in drum chippers so many times I could do it in the dark. Anvils? Nothing to it, all the way through complete rebuilds of bearings and drive-train components and alignments.

Never before have I heard of, or seen of such a thing as you describe.

Something is so incredibly out of wack it should be obvious.
Blades upside down?? the angle of the sharpening wrong??
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  • #10
Believe it or not it may be too sharp with the tolerances real tight. I just chipped maple and sweetgum today but it is gradually eating the big stuff better again.

My groundy thought it was just winter chipping of dead and dry(er) material that wasnt feeding too good.

I'm really strict about maintenance am pretty good with a wrench thats why it threw me. I think the chipper is just too dialed in for some material.
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  • #11
perhaps angle I left after touching them up effected things.....
Greenhorn, are you being a total Greenhorn? Run some real stuff through that machine, work it like a poor pimp works his few whores and then get back to us
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  • #13
Any last minute ideas

OK, this thing is driving me nuts. On the verge of financing a new chipper.
It wont " pull in " much of anything anymore. When it does the chips arent that bad though.

Its making these alot if the pics help - And I promise it nots an obvious fix - I replaced knives and cutter bar upon buying this chipper and set them to spec. The only thing I can think to change is the distance the knives stick out from the drum???????????????????????


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That and/or the bearings have alot of play in them making the clearances seem right, but when it hits wood the drum gets to climbing.
I'll vote for the new chipper. Jk'ing man hope you get it sorted out, sucks forking around with stuff when it doesn't work out.
  • Thread Starter Thread Starter
  • #19
yah, thats the only thing that makes sense
NO, not drum bearings it would shake at the least and self destruct.

The cutter bar is too high. Lower the cutter bar and put the blades out.
Do you have the proper angle on your knives? With my old chuck and duck if the angle was off even a little bit it chipped like shat.
Check your bearings, and make sure they're in spec. The easiest way is to remove the knives, and use a sharp pry bar between the bed and the drum to lift up, first on one side, then the other.

Set the knives so they're 1/4" above the drum.

Set the bed knife to .010" to .015" clearance from the knives.

  • Thread Starter Thread Starter
  • #24
I have touched up the knives with a little kitchen sharpener thingie but never re-sharpened, doubt I have changed the angle enough to effect much.

Manual says to put knives 4 serrations out from drum - which they are - 1/4" would be way less. I was thinking of moving them out even more - thus "pulling" material more aggresively one would think.

The problem seems progressive with no change in knife / anvil position so bearings then me thinks.

I want a morbark so bad though - talking to finance guy tomorrow.