PTO driven wood chippers

[Gordon Maney]

I would like to have a chipper, and more specifically, a PTO driven chipper. I have a tractor with a 73 HP diesel with which I would use a chipper.

I have read of the Vermeer chippers, they have a 6 inch and a 9 inch. I would choose the larger, just so it would take wood with branch stubs more easily, and my tractor would have sufficient HP to run it.

I am not a business, I just have a reforestation project that is generating ever more wood that I must process.

I cannot afford a new chipper. Frequently in my life I have fabricated things I needed that I could not afford to buy.

I work in the engineering department at a manufacturing firm [so I have design capabilities], have fabrication skills, and could sub out machining and fab processes that I cannot do in my shop at home. I have been thinking about building one in the same fashion that manufacturing industry might build a prototype machine.

The single largest items would be the disc and shaft, assuming I made a disc type chipper. I admit to not being very familiar with chipper design. In general, I think it would be easy to over-build one so it was very durable. I would use commercially available cutters that were OEM parts for some existing brand.

Is there a best kind? I read of disc and drum chippers. Are there manufacturer's manuals for chippers that show internal construction, whether they be service or parts manuals?

Does it make more sense to buy one that is worn out, and rebuild it? What all is subject to wear in a chipper?

Could a chipper formerly powered by a stationary engine be converted to a PTO drive? Do the two categories differ in operating speed enough that they are designed differently?

I am interested in whatever observations you may have regarding this subject.

[MoparNorm]

Hi Gordon,
I rented a 12" Vermeer once on a project. We had it from brand new for nearly a month on a project that we cut down and chipped over 150 pine, fir oak and Eucalyptis trees. It ran continuously, 8 hours a day. The BIG Vermeer worked flawlessly and we had an impressive mountain of chips left over, nearly 80 feet in diameter 25 feet high, the pile became so hot that it started to burn, luckily we put it out just before the landscaper showed up to buy the pile of chips from me! ha!ha!
I haven't the mental abilities to remember the model number but I would suppose that Vermeer has a web site with a parts catalog. That would be where I would start and see if they have diagrams and part numbers, perhaps even on line parts pricing so that you could see what you are in for.
The 12" NEVER clogged, it would chop up anything (remember "Fargo" the movie?) The design is pretty reliable and the mechanism does have a safety and cleaning mode which is very important. The horsepower that you have would be adequate, but I'm sure that the product specs will tell you all that you need to know for your design.
MN

[HWooldridge]

Gordon,

I like to rebuild and fab stuff but I have to opine that this is a major project to build from scratch. I have some experience with commercial chippers for plastic and they are built to high tolerances. In our machines, the bearings and knives were most subject to wear. The knives must be ground precisely as they cut against a bar so unless you just want to build one for fun, I'd suggest trying to find a self contained unit like a used Vermeer. The rental companies usually sell them after full depreciation so that is where I would look. As stated above, I suspect the engines, knives and bearings will have the most wear.