I have not actually resharpened my chipper blade (it will be hard to remove) but both logic And experience suggest that your probably dull blade is part of the problem. My vibration has increased some. I have also noted that old branches cause far more vibration then fresh ones. However, my chipper also has the big shute with flales that beat small branches into submission. Doesn't the Dr Chipper do the same?

Burning does seem like a good solution though. Mulch is great but too much work/pain is too much.

thx for your help. I got tied up getting a load of manure today and need to spread some now before I release my irrigation water as is my day to flood the property (every 5 days). I will see how the sharpened blade does tonight after I get the water done. My blade is a single blade 3 1/2 " long mounted to a flywheel. It may just be my arthritis being flared up a bit, good day/bad day thing. I really thought the longer I aged the branches, the easier they will chip, but there may be a opportune window of time where they sit for a month or so to not be green, but before they get hard and brittle.

Maybe I just try running the pile over with my ford F 150 and chip them that way, lol. Might be quicker and easier, who knows. I will let you know if I come up w an answer. Maybe I try watering the pile to "soften" the wood before I run them thru the chipper????

With my MTD chipper if the knives get dull I have to push the wood thru. If they're sharp I have to hold back on the larger limbs so it won't bog down.

You might want to use some Loctite when re-installing a chipper blade. All that impact vibration could loosen almost any bolt threads and it could be very hazardous to have a blade come loose while operating the machine. I use red Loctite on mine, which needs to be heated to unscrew the threads.

Not saying it can't happen, but I've had the knives out 3 times to sharpen and haven't had any problem. The bolts have self locker nuts and I don't spare the torque tightening them.
Mike