Something like this but there is no subtitles unfortunately
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Hi Johan, i belive this guy on youtube " Made in Poland" has built one of the single rotors rebak, as i remember he has subtitles?
Sorry about your axles, stainless really seizes if the tolerances are to tight, if you make the play bigger between the axles, then the shear bolt will jam in there instead, maybe one of them shear bolt disc-type will work? Are often seen on old hay presses, somewhat possible to adjust by using more or less shear bolts.
I know which way i would went after, say, three broken shear bolts: OK48…not recommended.
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Yes, I had that thought too. I should have made that type of shear disc instead.
I actually left a little gap so it could ’rattle’ around in there but it was not more than a few tenths of a mm, just enough for the grease to be in the gap.
I’ll look into made in poland
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Thank you Jan 
It was one of those I meant
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Is that a problem? You could join inner and outer axel permanently and still mount a clutch, right?
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In itself it is not a problem, I am definately using the axle for the knives again, just don’t want this to happen again (and it will if I put it back together as is) so I am rethinking the whole drive. The how and what of the whole drive.
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Is the shearbold really needed? Another relais with different motordirection if something is stuck? Make sure they cant work both the same time😀. Firework for sure
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It is very doable but I would like to have it mostly mechanical without sensors.
This is why I am exploring only having one set of knives, less moving parts and then possibly have a beltdrive from the gearbox as a slip instead of a bolt. Don’t even need the sprockets then.
This doesn’t mean that I abandon this version, just exploring which route to take solving the problem.
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I believe a one axle rebak will require quite a lot of force. Not only does one single blade have to cut through the full diameter of the wood - it has to overcome the friction towards the anvil as well. Probably why we see mostly thinner stuff being processed with that setup.
As I see it, a pto slip clutch on your rig as is would be perfect. You don’t happen to have one laying around, do you?
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I do have one but it is used on the pto axle unfortunately. I looked around for another one in the barns but didn’t find one as I started the build.
And yes, I think it uses more power too to be able to overcome friction and cut from one side only.
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I am afraid that there will be a lot of debris with 1 knife, will crush the wood. Will probably be the same as having a knife larger than 3mm in my clip, too much resistance, I guess.
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When slicing through the round piece of wood, the max force required is in the middle of the wood, and it will be a larger curve in the cut as in the wood because it will be slicing with the grain. But it eliminates a pretty expensive gearbox and extra set of blades, and bearings.
I don’t know if you can overcome it with say a curve in the anvil, or a freewheeling set of knives on the bottom, or maybe just a wheel that is offset from center. I would have to draw it out and think about it. 
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I wonder if a pipe roller instead of a stationary anvil would work?
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I was into thoughts like that too, when into building a rebak, i had a BIG roller of ptfe (teflon) plastic, about 5" dia, very hard, from a shipping container loading ramp.
My thought was just to use it as a free wheeling roller, could touch the knife edges without hurting them.
The idea wasn’t mine though, i saw a old machine built like that in a farming museum, used to cut animal feed, it used a big oak dovel as a “idler roller” only the knifes was much smaller.
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Here is the low budget version. 
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The wood in the still photo at the beginning looks a lot like sunflower stalk. The chopped pieces at the end look pretty pithy too. It’s clever, but I’m thinking oak’s not going to happen, and maybe not pine or cottonwood either.
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I agree. It would need, at the very least, a stronger motor and safety shields. I thought it was some species of bamboo.
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Sory Johan, cant help. They are all called the same here. Everything us a chipper 
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I used a special powerrelais to invert direction. Works perfect. But if you are standing next to the machine feeding it, it is not needed. You can switch it by hand. Easier than changing a bold.
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