my take on chippers.......
diesel is the only way to go and the bigger the better. basicly i chipped every thing. i don't care if it was a 300 year old oak, it got cut up and chipped.
after destroying a morbark model 17 i started to research the big machines. this was about 5 years ago. i refused to buy a morbark again. when i spoke to vermeer on the phone the steel specs seemed too thin to me. i ended up getting 180 hp 18in woodsman. the first machine i got from them was a hunk of junk. i was breaking welds after 6 hours. i tore the tounge of the machine. cracked the drum numerous times, bent the belly pan, cracked the hyd tank, broke bearing caps, had the trap door break out, cracked the motor mounts, bent the feed floor. they used the cheapest hardwear possible. when sweeping up after chipping there was usually a bunch of bolts on the ground. i then speced out a new woodsman with the help of my dealer to trade this 33,000.00 hunk a junk for. after giving them another 5600.00 and swaping my motor over i now had a machine with NO warrenty. it was a better machine but still had a lot of bugs in it. i still had to make alot of change's to the machine. the drum still cracked twice. the problem was they were being built in a factory set up for light gauge steel, so the machines were under speced.
the owners flat out lied to me. when i ripped the tounge off they just shipped another 1/4 in tounge. why not beef it up to 3/8 if the 1/4 in failed. so i had to wait till they shipped a 3/8 tounge. they really were pathetic. it was as if bob engler grabbed a six pack of bud in the morning and kicked open the screen door went out to the garage, then took a couple of bong hits and started welding these things up.
i now feel disc machines bon't take the pounding that drum machines do, since they shave the wood instead of pound it. the key to running a big machine is sharp blades.
the other thing all chippers have in common is you need to spend big bucks if you want it to chip big wood day in day out. just because it opens up to 18 in it's only for the occasional piece of 18in wood. like the second tuesday of every month. once you get up to around 45,000.00 will the machine hold up for the long run. the more horse power the better.
if i had to do it again i'd spec out a big brush bandit. the key thing is find a dealer you can get along with. have him spec out the machine since he knows what fails on it. no need to buy a regular production model. the dealer will get it beefed up a bit.
oh and did i forget to mention bob engler from woodsman SUCKS.