Portable Chunker

I have been working off and on building a portable wood chunker mainly for limbs and branches up to 3 inches diameter that I can take along easily to where the fallen material is located. This started out as a junk air compressor that I used the tank for my burn tube housing. The mounting plate, handle and wheels now become the frame for the 2 cylinder military surplus engine and the 90 degree reduction gearbox that the blade is mounted to. The lift off removable blade guard was salvaged off a defunct chop saw. Folding legs bring it up to standing working height so a five gallon pail can be slid under to catch the cut wood chunks. After a fuel tank is installed and a belt guard, it should be ready to fire up and try out. The engine runs at 3600 RPM and is reduced 60 to 1 through the belt and gears which puts the blade speed at 60 RPM or one cut per second. The blade profile increases diameter 1-1/2 inches for the first 1/4 revolution, then 1-1/2 inches for the next 1/2 revolution and another 1 inch for the final 1/4 revolution. The anvil plate next to the blade is adjustable for clearance and for possible future blade thickness changes at replacement. Hopefully I will get it finished next week and post some video of it running and chunking!

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Is there a stop for the chunk length?

Wes, it depends what angle you feed it. The gearbox housing acts as a stop at about 3 inches if it is fed more level and if it is fed downward 20 degrees it could shove in quite a way but you have to be quick because the first part of the revolution of the blade is aggressive.

I like it, a mini WK of the chunker sort.

Excellent! Let’s see it go!

Good Morning Don,

Great job on the chucker !!

After you use it a while and get a feel for it you may want to experiment with some weight ( flywheel ) on the incoming pulley. The extra momentum will make the chunking much easier on the motor and belt.

Don, I think you’re one of the first to think of chunking while on the road, kind of a Swiss Army Knife that can’t fit in a pocket!

Nice and compact. Here is what I have been up to. Not quite as portable, and it may need that flywheel that Wayne mentions.
Have fun with this one guys.

David S

Don , thats a good looking chunker man , you taking orders? lol

Couldn’t you just put a reducer on it and maybe add a fly wheel. Other than that I wouldn’t change a thing the fuel its makes would run perfect in our machines. Nice job!!

Don you beet me to it. That is just how I wanted to build one.

Maybe I am stealing Don’s thunder here. I should have posted this on its own thread so people don’t get confused.
Sorry Don.
Maybe Chris can move it.
David S

Hi DavidS
That is one mean chunker, a flywheel will defiantly help.
Is there just an auger screw in the tube?
Have you sharpened the edges ?

But please don’t climb over a drive shaft like that, I have had a staff member caught up on a shaft and beaten to a bloody death before I could shut the tractor off and I was in the drivers seat. I still have bad dreams about that!

Cold shudder

There is an auger in the tube. It is 3/4in thick flight with a 45deg bevel on the edge with sprayed on hard facing sharpened up pretty good.
Thanks for the concern on the PTO shaft. I knew that would be one of the first things many would caution on.
David S

3/4" thick auger fighting??? how or where did get that???

Had it rolled at a place called Falcon Industries in MN that makes all my special flighting.

Thanks for the comments everyone. John, I was complaining the other night on the hangout that all my wood is under 3 feet of snow so I could not try it out-and Terry L wanted to see it run so bad that he wanted me to video it cutting up my broom sticks! Wayne; Matt, and anyone else - I am open to ideas on how to mount a flywheel. I want to try it first though because I want to keep it light as possible. David S, no need to move your post- we’re all in this together. I am concerned though that if your screw chunker can kill your tractor that I might need that flywheel too. Patrick, I agree with you about the pto-shaft danger. We recently had a farmer here now named “the naked farmer” who stumbled into one and it took him round and round beating him against anything in the way until he was left with only one sock on. He managed to get back on the tractor and drove 1/4 mile back to the road in freezing temperatures where a passing first responder fireman got him the help he needed. Lucky to be alive but a long recovery ahead!

That is very cool David

Yes both machines are very impressive, cant wait to see Dons up in action. Yeah Don you are just south of me and I have an average of 2’ or more in our yard.

When we get through this cold spell and I’m done thawing water and sewer lines, I want to get back to my build.
I also want to make a chunker. What I was thinking about for a flywheel using a dumb bell weight. I’m sure I can find one at a thrift store near by. I would like to run it off of hydraulics. I was hoping to keep it small like yours Don.

Nice work guys. Both of them look really good. Don you might need a centrifugal clutch to keep it from stalling out. A flywheel could be mounted on a jackshaft.