Rebirth of a 6 Foot Flail Mower

[awemawson]

PS    if you used photobucket I would not have to click on every photo to make them large enough to see   

And in a little while they'd all be lost to future browsers of the forum like so many earlier threads 

The 'Bunker' is a Water Pumping Station - the white tank looking thing actually IS a tank open to the air. Years back Hastings Waterboard used to pump water from wells a bit up the valley from here and treat it in that building. At the time they owned my farm. Now although the building is still full of the 1930's equipment they no longer use the well due to the high iron content, but have erected a container like structure in the front that does all the pumping and also houses a back up generator. The masonry building has numerous pipelines entering and is a major junction between three reservoirs so they have had to retain it.

[RobWilson]

Cheers Andrew ,
           I thought it may have been part of your farm buildings ,some agricultural thing .

And in a little while they'd all be lost to future browsers of the forum like so many earlier threads 

Just pulling your leg  about the photos .


Rob

[awemawson]

Just pulling your leg  about the photos .


Rob

[awemawson]

I know  but it's a serious point - accounts get lost and the thread looses it's context when Photobucket or other service no longer carries the pictures

[RobWilson]

I know  but it's a serious point - accounts get lost and the thread looses it's context when Photobucket or other service no longer carries the pictures

Aye you do have a good point , but it all depends on how you look /use a forum , me I see them as a magazine .  Anyway maybe this topic should be discussed  its own thread so that it does not drag your repair log off topic .


Rob

[RobWilson]

Looking at the photos Andrew it looks like that mower has had  absolutely no maintenance done on it since it left the dealers 


Rob   

[awemawson]

I reckon it was driven by a maniac through a war zone - just my sort of re-build 

[PekkaNF]

They are shielded bearings, the main flail shaft has a housing that surrounds the bearing on the inner side, and the roller has a secondary seal on the inner side of the skids but it's exact form is not obvious due to gross manglement 

Normal bearing shields are not very good on this one as you have seen. Grass/hay and other stuff has tendency to wrap around and attract debris, then shield is shot and next bearing. I have seen plastic fat shields, metal saucers, rubber grommets and in combination. Large discs close to bearing seem to work, but complicates structure. Not sure if gammaring is good?

Pekka

[awemawson]

Pekka, if you look at this picture you'll see the main flail shaft bearing is recessed into a shroud. The back roller bearing had an inner housing that probably had a simple seal, but as you can see in the second picture it is totally destoyed

[PekkaNF]

That looks familiar. Forage harvesters had some accid feed in to preserve the grass and they lived hard life, even when they had a wash down of the innards. Only way to keep them operational was to pump grease trough the bearing after use to purge the debris out that was about to reach the seal.

I bet it has better life on your hands.

Pekka

[awemawson]

So it took all morning and blood (literally - squashed little finger  ) sweat, and tears but the Jackshaft is OFF

Initially I got the Universal Joint yoke that is stuck on the gearbox output shaft glowing dull red then tried tapping, levering, pleading etc to no avail.

Left it to cool while I removed the four sheave pulleys on the left had side - sadly although they are held on by taper lock inserts, in both cases the taper locks were cracked - standard 2" Imperial size, only £18 each to add to the butchers bill 

When the yoke had cooled again I liberally sprayed it with PlusGas and set up a wedge arrangement using the tapered end of a large cold chisel to bear against a loose bolt head that I inserted in the hole in the end of the splined shaft the other side being a heavy flat bar bearing againt the opposite yoke cheeks. Much hammering, readjustment and a few oaths later I had JUST perceivable movement. At that point I knew I had it, and persistance adding more packing and repeating the process eventually got it to slide off. It was at this point the jackshaft fell off and squashed my litle finger 

Anyway - good progress, just got to get the bearings off the end of the main flail shaft, and pull the gear box off to measure it's bearings.

[AdeV]

I love watching your re-build threads Andrew. Regrettably, I rarely have anything useful to add (I don't this time either) save to say - thoroughly enjoying this one, even though I will likely never use a flail mower in my life, and have only the vaguest idea how it works... (I get the roller bit).

No pics of the finger then?

[awemawson]

Ade - you're a Ghoul !

Well a bit of a delayed start today as I had to visit the dentist to have a tooth pulled out  When I got back I set too removing those flail shaft bearings. Both sides needed the inner races grooving with an angle grinder and cracking - but off they came 

This has allowed me to remove the (blooming heavy!) flail shaft itself - so as far as dismantling is concerned, apart from the 90 degree gear box we're nearly there.

New bits that I've ordered have started arriving - the main flail and roller bearings, which I'm relieved to say ARE the right ones, and a few of the bigger bolts.

I've now to decide about grit blasting and painting - needs to be outside and the weather has changed for the worse. I may have to rig a tarpaulin tent if it doesn't improve.

[wgw]

Many years ago I used to design stuff like that. Any bit of string or a tough grass stalk would tear any bearing seal in a flash. On the posh stuff designed complicated labyrinth seals for wheels and flail shafts but never lasted long. We found it was cost effective to just use MS shafts and iron wheels, and change when needed.

[awemawson]

So before going in for breakfast after mucking out the pigs I got the Forklift back in and turned the flail back into the 'operating position' so I could more easily get at the 90 degree gearbox to remove it.

Gearbox came off without any dramas, however getting the flail into this attitude had revealed another issue that I need to address - someone in the past has caught it on a fence post or wall corner and twisted the 60 mm o/d tubing that forms the hoop of the three point mounting, and have done a grotty weld on said tube  I'll have to cut this out and re-do it. The twist in the hoop doesn't look too bad in the photograph but it's a few degrees.

Anyway after breakfast I dismantled the gear box so that I can identify and order the required bearings and oil seals. The tube issue I'll sit on for a bit and see if any good solutions crop up.

[mattinker]

Andrew,

I must say, I do like it when you start unravelling old sweaters and knitting new ones with the wool!

Regards, Matthew.

[DMIOM]

Andrew,

I must say, I do like it when you start unravelling old sweaters and knitting new ones with the wool!

Regards, Matthew.

Me too!             

Dave

[AdeV]

Ade - you're a Ghoul !

Hehehe   

I had to visit the dentist to have a tooth pulled out 

  

Anyway, how does a squashed finger lead to having a tooth pulled? 

[awemawson]

Andrew,

I must say, I do like it when you start unravelling old sweaters and knitting new ones with the wool!

Regards, Matthew.

..ah - you spotted that the family tradition lives on 

[awemawson]

So Friday brought another delivery - this time the laser cut 10 mm thick steel disks that will form the ends of the roller. One will be inserted about 6 inches from the end, with a second at the end, both pierced by the axle shaft. There will be radial holes drilled in the tube where the deep disk goes so that I can plug weld it in position. Using this construction ensures a reasonable alignment of the axles at each end.

Rest of the day and this morning was taken up dismantling the gear box. It put up quite a struggle. One bearing inner had to be sliced and cracked off. The crown wheel was mighty tight on it's shaft, I had to rig packing within the casing to support it in order to use the 60 ton press on the end of the shaft. Then the last major pain was removing the 1.5" 16 tpi nut that adjusts the pre-load on the taper bearings. Originally equipped with two wimpy holes for a pin wrench there was no way it was coming off that way. Eventually I gradually increased the size of one of the holes until the hole met the outside periphery of the nut allowing me to use a small cold chisel on the remaining bit next to the thread to crack the nut. Then it was mine and I could unscrew it.

Probably need to make a new one as I can only find metric ones listed.

Still now at last I can put in the remaining bearing and seal order.

[awemawson]

So this afternoon I made a new locking nut / bearing adjusting collar. Turned out ok 

The curious 'upstand' of reduced diameter is actually a form of locking washer attached to the nut bit. It is punched down into a recess in the shaft in two places to stop the nut unscrewing.

[awemawson]

So at long last the bearings and seals for the gear box have arrived so I'm glad to report that that is back together, and even filled with fresh Hypoy 90 gear oil. 

So now to get on fixing the tubular 3 point hitch frame with a break and a bend  I decided that the easiest thing to do was to cut it apart, insert a tight fitting bar up the tube, and weld it back together. There is an angle iron stretching across the width that must have been hit by the PTO shaft as it is well bent and also needs replacing.

First thing - cut it apart

[awemawson]

Now this is substantial 60 mm o/d tube with a 5 mm wall, and as luck would have it I have some lengths of 50 mm EN8 solid bar which is a nice sliding fit. So the plan is to slide a bit of this bar across the pipe join, weld it in with plug welds through drilled holes, then weld the chamfered end of the pipe back together.

[awemawson]

The forecast was reasonable for today - or at least more reasonable than the rest of the week so I thought I'd try and grit blast and spray the various components. We're off for a few days holiday at the end of the week and I was keen for painting to happen before then so it can be hardening off whilst I'm incarcerated in a Motor Home 

It's always a big bind dragging out the blasting kit so I really wanted to get it all done in one session, but doing the main chassis took ages (and seven bags of crushed glass!) so I cut my losses and confined myself to just getting the chassis done.

Started as the sun came up and had got the etch primer on by 12:30 - still rather overcast but after lunch the sun broke though and the chassis was actually warm to the touch, allowing a coat of top coat to go on.

[awemawson]

So I still have this pallet full of bits and pieces which will probably have to wait for my return from our brief time away, as I've lost the will to live when it comes to blasting