'm on my seond PTO
chipper, and I love them. The first was a 4" Patu DC40 with manual feed. I ran it off a
B2400 and
B2910 (24hp and 30HP respectively) without problems. It's a great machine and I'd recommend it as a lower cost starting point. They can be had for around $2500.
This year I upgraded to a Salsco 824 in order to get hydraulic feed. What a difference the power feeder makes! Much more gets chipped before I wear out for the day. Not cheap, though, at about $5000.
One word of caution, is to watch the weight of the unit. They are surprisingly heavy and the weight is very far back. I almost bought a Valbe CH160 with hydraulic feed and the dealer wouldn't sell it to me - said my tractor wouldn't lift it. I then got the Salsco which is lighter by a few hundred pounds and my tractor couldn't lift it either without alot of hand shoving. Turned out my lift relief pressure was off and once I set it correctly the Salco lifts, but it's right at the edge. To put it in perspective, the Salsco is listed as weight something under 700lbs, and the rated lift capacity of my 3PH at 24" behind the lift points is 1300lbs! It gives a sense of how far back the center of gravity is with the
chipper.
Check out the thread on the chinese
chipper. It looks very intersting and a much more cost effective alternative, asuming parts are available etc.
Bottom line - I'm a big fan of 3PH chippers. There's no comparison to a stand alone 8hp MTD.