If it has not enough power I have a 400V / 500V transformer standing in one of the barns so I can just plug that in in between if necessary
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A safety mechanism so your hand doesnt get caught in it for some freak accident.
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That would have been nice. Perhaps brake is the wrong choice of word, it was more of a stop so the motor could never spin backwards.
I can make a picture of the part later, the motor axle was kind of dragging two parallell discs with lots of small excentric ’hooks’ against an outer housing so if the motor would start to spin the other way, they would engage into the housing. I hope it makes sense, it probably will with a picture.
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No need for a picture. I have seen similar mechanisms. It is called a “an anti-reverse rotation device” or anti-reverse coupling" I had to look it up. I was thinking if it was a brake, then it would stop any momentum, but it is not, so irrelevant unless you are maybe using the motor for say an elevator. 
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Yes, exactly like that 
A brake would have been nicer but I am thinking to make some kind of funnel long enough to not reach the knives even if I put my whole arm in.
OR make it small enough to not fit the arm in at all and only fit thicknesses that it can handle to chunk.
My dad came with an idea to make a feeding funnel that acts as a de-limbing knife as well that shears off the limbs to save the total time. Kind of like a timber harvester but with a fixed round knife. Well worth a shot as an add-on later when I already have some chunks 
The limbs are not so thick on those small trees so I hope that it won’t stop the tree when it travels through the rebak.
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I have no intension putting a wet horse blanket on your enthusiasm, Johan 
It’s all about personal preferences, but I belive the total amount of work is reduced if the brush is left in the woods - even if it means manual labour delimbing. You’ve probably at some point knocked down a big garden tree. Sooo much extra work dealing with the brush compared to leaving as is in the woods.
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All opinions and comments are welcome and that would be my concern as well. And also if there is a weird angle on the stem it could get stuck.
Do you cut the top of the trees as well so there will be less very thin stuff in the gasifier or is it a too small percentage to bother with it?
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Yes, I do cut the top off, about where it has the thickness of my thumb. To be cleaned up, most need just a few strokes, while you’re picking them up and loading them anyway.
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Yes, makes sense.
I do know that I have a tendency to overwork and make things too complicated, I need to be more of KISS
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I have an underwork tendency 
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I don’t like leaving brush, because it doesn’t let the trees grow in that spot, here the vines (which I don’t want) take over the pile, and it reduces fire risk. As far as fuel, it is probably a better candidate for charcoal. because even after it is all chopped up, it still has a lot of air gaps in it and has a pretty high ash content because of the bark on it. A lot of it ends up as garden food.
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Different circumstances. Up here long, straight young growth will be back in a couple years and the old brush gone. Covered in leafs in the fall and compacted by snow during winter will make the brush decompose in no time. Vines don’t exist other than planted/foreign/ornamental.
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Very interesting information Johan, i have a smaller geared motor laying around, i wondered what the “wheel” behind the fan served for purpose. Must be something like yours, only the wheel left on it.
Those 500 volt motors (industrial surplus:grin:) i got some myself, had no luck with the one i put on my homemade hydraulic log splitter, it seemed to missing “momentum” it stalled when i loaded it hard, altought around 3hp. Someone told me i should run it in “star” connection instead, but that should be worse i believe.
Transformers 400-500volt sounds very interesting, do you now any applications they can be found?
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Yes, they lose quite a bit of power but running it in Y- mode or D-mode for that matter depends on how the motor is ’wound’, it says on the plate how you can run it.
Transformers 400-500V can be found when older bigger companies shut down, companies these days tend to go for 400V or 690V for avaliability reasons (more choice, larger series, cheaper). 500V was used for saving reasons, as is 690V these days, so you can spend less money on cables, so it is really only bigger companies with lots of motors where you can find them.
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Thanks, im going to check with some friends that work in that business.
I know 500-690volts are good way to make some stuff cheap on the “used”-market, i got two big welders for free, tig, the oldest one run really crappy on 400v.
The new’er one, had the full possibilitys, 290, 380, 400, 415, 500, 690volts. Only drawback it’s single phase (between 2 phases) 63 ampere, i start it through a (elpatron) which i short out as soon it’s up and humming, otherwise my fuses pop like popcorn
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Older 500V welders, at least several Westinghouse welders I have come across, often have an option inside to run on 400V also, they are already wired for it but it doesn’t say on the outside. Perhaps others have that too.
The downside of running stick welders on the wrong voltage is that you get the wrong voltge to the electrodes which then makes it harder to weld with, perhps even a lower quality weld (not sure about that last one though)
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Yes, as for tig, it ran Really crappy, that old one had no other options than 500v, so i “recycled” it.
If i remember correctly the plate said it was “special delivery” for Motala Verkstad.
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By the way, I don’t think I have seen one of those transformers any smaller, to run a motor on, than 10kVA (I have not been looking very hard though). Just in case you stumble over one 
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It took me pretty much the whole day to drill those 16 holes in the 8 knives, sharpening drills twice on every hole, once with the pre-drill and once with the 8mm (5/16”), regular drills did not work so had to use sharpened masonry drills.
Also broke three or four drills, the hard steel tips broke off from the drillbits.
Its starting to look like something now
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