I’m sure it would and a mono-rebak is only half the work to make. So, if you’re starting from scratch with a stronger motor and if you accept more debrie…
It’s just that Johan has already built a much better machine. I have nothing to do with it, but I would still find it disturbing if he decides not to utilize the state of the art rebak he has already put so much effort into.
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If the bearings hold, you can still put pulleys there, so the belt slides as protection.
Or sell it to me, I think it’s a nice build. 
:grinning
Edit:
http://www.backia.se/sida7.html
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I agree with J. and J.
You had a wonderful electric gear reduction drive available.
You studied then made up a world-class branch and splits-sticks chunker.
Unfortunately coupling the two together then the project Frankenstiens a life of it’s own.
I suggest you approch the task diffnertly.
The goal was to make woodgasifier chunks, period.
In your clipper assembly you have half the system. Friction drive it through a rubber wheel driving or driven; or slippable drive belts using a different motor or engine power source.
Think about it. If, when that unique all-in-one gear reduction box fails you’d never find an exact replacement. Then be having to repurpose a different drive system anyway.
Just do it now with a can-retrofit-to-many, drive system.
Regards
Steve Unruh
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Well, replacing the reduction wont be a problem, probably the price will. Expensive piece. And the motor will stall before the gearbox breaks.
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I am not understanding the issue quite right, which isn’t your fault. Are you saying the frame twisted slightly when you stressed it? Then it added grooves to the axles because it wasn’t lined up quite right and now you can’t get the knives lined up square again?
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Thank you all for your responses and help, it is a bit overwhelming getting help from people near me and from far away, all over the world. You are truly nice and helpful people on this lovely forum 
I made up a gameplan this morning while having my cups of coffee alone when the rest of the family was still asleep.
This is the axles as they were after getting them out yesterday.
This is my plan that now is in play, been at it some hours.
I will not abandon my rebak with two sets of knives for something less good.
I’ll make a new shearing mechanism with two discs so no axles will spin inside the other and wreak havoc (as I should have done to begin with).
Had to get some new material for adding to the bottom plate as I have to move the rebak away from the gearbox to gain space for the new shear bolt coupling and for the two shear bolt discs.
Drilled a few holes 6mm (1/4”) and two 8mm (5/16”) for shearbolts, the other two big holes were already in the steel plate plus the centerhole 20mm (3/4”)
This will be welded to the axle from the gearbox and one of the discs welded on that, the bearing pressed into the hole as a support and freespin for the axle from the rebak (which will have the other disc welded onto that)
The first welds on, needs to be turned in the lathe to make straight faces for welding the sheardisc and the bearing surface so they will be straight
I hope this explanation makes sense
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No, the shearbolt snapped because I tested the limit and then the two stainless steel axles (one runs through the other through the gearbox and then the shearboly is on the other side) seized together, stainless is ’dry’ and does that easily. I didn’t leave enough play gap apparently.
Am I explaining understandably? I know what I mean but that doesn’t mean that others do 
Edit. The frame is not twisted or anything else, just the seizing of the axles is/was the problem
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What I see is a mushroomed axle. It looks like it got too hot when it was too tight, and the metals expanded at different rates. which is tolerances but definitely fixable if you can machine or file the ends down a little to put a slight shoulder on it.
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Absolutely, I will use the axles again. They have already been turned in the lathe and prepared for the next steps
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I was going to say if you were going to machine it, you might add room for some oil imprenated brass bushings so you have some sacrificial metal to wear away. BUT nevermind, you are way ahead, I will stay out of it, and enjoy the ‘finished’ video. 
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All input and ideas are always welcome with me, no need to stay out of it if you want to say something or have a question, this goes for everyone 
Btw. Oilimpregnated brass bushings is a good idea
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Too late! I am already fluffing up the la-z-boy and making popcorn for watching the video on the bigscreen! (we have an obsession with consuming popcorn while watching movies in the states.)
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Hahaha, thats great.
Popcorn and movies goes together nicely
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My wife has been on a kick of popcorn and red licorice in the same bite, I about hurled they first time I saw her do it. Weeks and weeks later she finally convinced me to try it. I can’t explain why as the thought is revolting bud red vines and butter popcorn is a match made in heaven
Sometimes odd things go together
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Is it something like this that you intend to do now?
It seems to work well.
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The rebak itself will still be the same now, the change will be the safety shear bolt (in case someone throws in a metal rod or something 
)
It will be something like the flange coupling in that video but only a 6mm bolt holding it together so it breaks and saves other things from breaking.
Edit. A 6mm bolt to start with, if that breaks easily I can put in two or go for a 8mm bolt but I think that would be a lot.
There is one 8mm shear bolt in my mower crusher for comparison.
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Hey Marcus, us hard core eat black not red with popcorn. Lol, lol.
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I toltally agree-- i would be looking for about a 2" hard or semi hard drive shart=or maybe an old semi axel shaft so i could break bigger wood-- and a heavy duty gear box low rpms.Though that vidio that JO posted- shows the basic design nice and clear. USING home built gearing could save trying to find a hard to findgear box with enough gear ratio .
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Sometimes stuff gets done on the rebak, today the shear bolt couplings got done, machined the welds and the plates plus fitted the bearing for the support where the axles are in eachother.
Plus the driving shaft got machined down so it is only full diameter where it needs to be
The driving axle
With the bearing
And the rebak axle
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Finally some more time to get closer to chunking.
My dad was kind and drilled holes through the knifeholders some days ago since I decided to weld the knifeholders to the axle. It felt as the woodruff keys and the space in the knifeholder is going to wear out too fast, it opened up a little only with that testrun I did. Too bad with that work for nothing but it is what it is.
Anyway. He drilled three 10mm (3/8”) holes under each knife so 24 holes in total and I welded and grinded it down flat.
I put the axle in the gearbox and the axles back in the rebak with the bearings and sprockets on too and put the whole thing back on the mounting plate.
This is what the shear bolt discs look like mounted
The biggest downside (and it is kind of big) with this shear bolt assembly together with the welded on knifeholders is that I can not exchange the one bearing (and not the sprocket either) between the rebak and the shear bolt disc but it is highly unlikely that I need to do anything with the sprocket and if I ever need to replace that bearing I’ll have to say a few well chosen words and then cut the axle and weld it back together after replacing the bearing.
This I don’t see happening ever with that low speed and the usage time being fairly low so I’ll take that if it happens.
Of course now that I said that it will happen soon…
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