On Fri, 4 Feb 2005 21:07:04 -0000, "Moray Cuthill"
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Good rundown.

You left out the hammermill style. These are simply flails, on a
spinning frame, that thrash the wood to pieces. They are incredibly
noisy, but are very tolerant of dry wood and stones etc. Get a piece
of gravel in a disc or drum cutter and you have a major sharpening job
on the blades.

They work much like a sort of multi-layer, multi tine lawnmower.

Some of the largest mulchers have gone to this style, as have many
garden ones. The main advantage is sheer toughness. I have dropped a
3/8" hardened steel chain into a tractor-driven one, and it broke a
belt, rounded the flails a bit, filled my undies, and completely
destroyed the chain. The machine still works, although not as well.

Also, all blade style chippers need to be kept very sharp, and are
best given only green wood. I have a drum style one, and when it's
working we spend nearly as much time sharpening as chipping, to keep
the thing easy to use and efficient. We used to sharpen every couple
of truck loads.

All chippers are extremely dangerous. Hydraulic feeds seem to help,
but in many cases have actually dragged people in anyway, in spite of
stop bars etc. Hydraulic feeds certainly lower operator fatigue
(DAMHIKT) but are costly and complex.

Anyway, all of this says that there is more to making a chipper than
meets the eye. They need to be well-balanced, very strong and with
very hard yet tough cutting surfaces of whatever sort.

Actually, talking of lawnmowers, a nice mulching tractor mounted mower
may do the job.


"Rod Richeson" wrote in message
...
Anyone built a chipper before? I have a Kubota with 15HP at the PTO and
would like to build a chipper to aid in clearing some vacation property.

I looked in the dropbox and google'd but it seems everyone is asking, and
no one is answering.

Thanks,
Rod

I have previously found a site showing a home made chipper, but it was not
that big. From memory it was a larger version off a small domestic chipper,
running of a single cylinder petrol engine (between 5 and 8 hp possibly).

There are several different forms of chippers. The type you would probably
be most interested in, would be the most common version off
industrial/arboriculture chippers. These consist off a flywheel, with 1 or
more blades mounted on them. The flywheel is normally constructed from 2
discs off steel, joined by strips of steel welded radially from the centre
out, so as to create a centrifugal fan. The blades are then mounted in cut
outs on the face off one off the discs. On basic chippers, the blade is
simply mounted onto the face off the disc, whereas a reasonable chipper, the
blade will be mounted onto an adjustable block, as the distance off the