Anybody know how to build a chipper?

eazyduzzit · May 16, 2005

I would like to build a chipper for tree limbs. I have a lot of pine trees I'm wanting to remove, and I'll use the logs for lumber, but I don't want to burn the brush.

I'd like to build a good solid chipper. I can figure out the frame and drive, but I would like to see a breakdown of how a chipper actually chops up the wood. Does anyone have any ideas on how to construct this part?

slowrev · May 16, 2005

The ones I have studied have a large flywheel with one or two short sturdy blades that cut the wood against another blade mounted to the case/chassis. the limbs are fed in against the stationary blade and the flywheel mounted blade comes around and chops a git off the limb. repeat process many times per minute.
Balance of the wheel would be an issue here. And everything must be very sturdy.

Ben

beenthere · May 16, 2005

Slowrev gave a good description of the part you need to construct or buy.

The flywheel needs to be heavy to keep the energy up while slicing off the wood. The blade(s) must be set into the wheel such that the 'bite' depth on each pass is limited to what the energy in the flywheel can handle. Engine size will have to match the size and weight of the flywheel to get it up to rpm and maintain that rpm while doing some work.

Interesting challenge, IMO, to build a chipper. I would think with your interest to build one, you would have already looked inside one, but maybe not. /forums/images/graemlins/wink.gif

Maybe renting one and using it to see how the system works would give you some good ideas for improving or matching the working system.

slowrev · May 16, 2005

One other item.
Behind the chipper blades there is often a flail type of mechanism to further reduce the chips or to thrash small stuff up.

I have an old corn chopper I am going to see if I can make a shredder for small branches out of. Pto driven so power will be no problem /forums/images/graemlins/smile.gif

Ben

eazyduzzit · May 16, 2005

Interesting challenge, IMO, to build a chipper. I would think with your interest to build one, you would have already looked inside one, but maybe not

If I had one to look at, I would just use it to do the chipping. /forums/images/graemlins/smile.gif

srscott · May 16, 2005

Instead of building one from scratch what about finding one that needs to be rebuilt? The flywheel balance issue is very important I didn't make a chipper but I made a vac/shredder for a home made yard vac. I thought that I had it balanced well but I guess not since it ruined it's mount bearings.

nomad · May 16, 2005

If your pine tree limbs are not big in diameter, you can have a small size flywheel such as 3/4" thickness and 20" diameter. Casting and its balancing this flywheel will be most difficult part of your work, but this is not necessary. Cut it from a thick plate by a plasma cutter, weld some wings on its back of flywheel and balance the flywheel assemble. Since you cut it from homogeneous plate, balancing will not be difficult. Then, get a hard material (best is "improved" grade 8) to machine its blades using a milling machine. Then, take the blades to a heat treatment furnace company to harden. Then, final process is grinding them. Mount the blades, flywheel, 2 pulleys (diameter ratio about 2 for 540 rpm) on a strong frame. Another important thing is alignment of forces; should be in the same axis not to cause vibrations and moments on the bearings. That's all. If these seem to be too much work, I can send you my home-made chipper (see attachment.)