Building a flail mower

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Got the gearbox mounted. I need to take it off together with its mounting plate, so i will bolt it to the body with three M16 bolts. The mounting plate will need some reinforcement ribs because the four XPB belts will pull harder on it than a PTO shaft would, in the gearbox' original application.

the tilt arm bracket i need to do again, i drilled a 31mm hole with a 30mm drill. I will drill the next one with a 29mm drill and see if this gets a nice and tight fit

 

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As promised, sloooooww progress.

As said, the previous tilt arm bracket pinhole drilled 30mm turned out 31mm. So i picked up steel to make a new one, drilled 29mm... to measure exactly 29mm hole diameter. So i ground my 30mm drill precise, drilled the hole out with lots of lube, and got a nice tight fit of the old cylinder rod which i want to use as hinge pin.

Got a reinforcement plate for the angle gearbox mounting plate, bent in contour on my shop press too.

Without the brain injury i incurred 18 months ago i would do twice as much in a day, but this is my therapy.... On my way to full recovery, i'm sure

 

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I lit the heater with open doors. Darn how dusty, brushing the rust off the inside with a wire wheel...

People are already lighting firecrackers which the dog hates, so she was under the old tractor cab in the back of the shed. When i went for coffee at the neighbour, i went back for the dog. When she came out, even she was sniffing and sneezing.

anyways, i was done with it, so lets see if Rust-o-leum primer delivers on its promise of sticking to wire wheeled rust.

Next is sealing between the chain welds, when thats dry, another primecoat with slightly more red mixed in (i mix red and whitish gray) so i can see from colour what ive covered and what not. Also i try to match the shade of RAL 2000 orange topcoat, for better coverage of the colour.

Even the factory welds didnt have al spatters removed, so i decided to not polish a turd (off course you can make it shine in the moonlight, but its still sh`t)

 

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Hmm i hear rats between the roof... oh no, Kira just woke up under the steel rack..

 

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Got the topcoat on !

Tomorrow my job calls again. Saturday it will be dry enough so that i can mount the rotor.

The headstock with side swing must wait till later, because i need it to run at January 13th. The road here, has no verge, the asphalt borders directly to privately owned bushes and shrubs. Tourists love it, but i hate it. The municipality will place roadsigns, so that anyone who continues, can not sue us over fallen branches. Especially bicycle racers are bad, they dont listen to your warnings but just race straight into falling trees, and still get mad at you. Anyways, damage is on them if they do stupid behind a road with restricted access due to works.

Anyways, i will do the sawmen a favour by slashing as much as i can, so that they dont have to push themself ass first into a shrub to get to the sticks, without peeling their eyes out on the branches.

Manufacturer of a machine with similar flails says it will handle 2 inch branches, but we will see what it will handle when i slowly drop the mower on top of one...

Anyways, in the background you can see the gearbox and the gearbox bracket suspended from the engine hoist.

To do list:

Mount flail shaft
Mount gearbox and pulley
Weld new brackets for the depth rollers
Weld up the worn shaft stub of the roller and grind it somewhat round, and convert to El Cheapo flange unit roller bearing

When all works and i am satisfied with the parts ive rebuilt and painted, the next thing is the headstock: It also needs new bushings and new hydraulic hoses. I must make a belt cover. And if my tractor handles it well as is, i want to extend the swing arms to increase the offset stroke from 2 feet to 5 or 6 feet, do away with the leaf spring bump safety, and convert to one telescopic swing arm with built in hydraulic breakaway safety.

 

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Got the gearbox mounted: I stuffed the 6 splined PTO sleeve full of copper grease, so that it wont slam out overtime. The thick stuff did make it necessary to use a rubber hammer. Anyways, i'll touch up the paint when its all done anyway.

You can see the Hemos flail head is intended for an angle gearbox with a flange with two bolts and centered with a 115mm bore ridge, but i welded a PTO bushing in front so i can stick the Holaras silage spreader PTO shaft into it, so the reduction drive becomes an overdrive.
Its straight cut gears, its probably going to whine at 2000rpm output speed, but so be it.

I also ordered new flails. 42 flails for 210 Euro is fair. Cheapest i could find online. They should be in on Friday.

These J type flails are a bit more heavy duty than Y flails found on most budget flail mowers from Delmorino and the such, yet they can take more abuse, rocks and logs than forged flails. It should chop branches up to 2 inch on the go (and probably more when you slowly lower the mower on it at standstill)

One side of the depth roller had a bodged up unit roller bearing and the other side a nylon bush that wore through and wore the stub shaft thin. Without machining a slide bearing is gone fast, so i welded the stubs up and ground them to a tight fit with the busted old roller bearing. The new ones have two grub screws, which will take enough slop out of my angle grinder fit for this slow speed roller.

And i made some roller bearing brackets. I can only use the top two holes for depth adjustment but i didnt feel like welding the others shut. Its not in sight...

 

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Yeah, they were definately used up..

 

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Got the roller mounted, and the new flails.had to grind through the rollpins and smash it in the middle to break the rust fit free, then i could tap them out. I replaced them with M12x90 class 10.9 bolts, so next time i have less work taking them out: A single stroke of the grinder should suffice, even if the exposed thread of the bolt gets smashed.

I also welded the bushing to the draft arm. My neighbour lathed it at work in lost time, and C45 was the only available material. Because my preheating calculation excel sheets are at work and the IR thermometers too, i stoked it blue and welded the carbon steel bushing to the mild steel tube. C45 carbon tool steel isnt my choice, but when i get this for free, i use a little extra gas to preheat and be sure it doesnt fold down with a bang on the road.
There will be a spring latch holding it in transport position, but i still rather be safe than sorry.

now the part that needs preheating is done and cooled, i can test fit it and determin the yoke on the other end in place, without burning my hands or my paint.

 

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All right i made it dirty. Luckily the rotor wasnt bent, it ran without vibration. The reduction gearbox from the silage spreader didnt make weird noises either, now its ran at 5 times the output speed.

Now i can take the pitman arm out of the folding mechanism, paint it, and drill grease zerks to the hinges.

 

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The ticking you hear is a sideshift hose ticking against the PTO shaft, so i turned it off before it grabbed... otherwise no funny noises

I just need to install an extra remote valve before i can stick those sideshift hoses somewhere safe