MadModder

OK let's try and split that nut with careful drilling' Progressively opened a hole up to 7 mm by which time there was a vary thin web left between the hole and the nut recess:

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Cutting the web with a small cold chisel that conveniently jammed in the nut extraction recess and cracked the remaining steel until:

I WON !

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So it turns out (not surprisingly I suppose) that  there's a locking tab washer under the nut - maybe THAT's why it wouldn't unscrew !

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So  this means that I should have a clear path to the next bit of dismantling hopefully.

So let's make a box key spanner thingy:
OK how do I mark out the tube as I have no centre to work from. Various thoughts - print a tape of the same length as the circumference of the pipe - measure it out - mark pipe from it. Not very easy to get the sizes right. Alternative plan - draw up end of pipe in Autocad print it out, stand pipe on it and transfer the marks. This is the method I chose but needless to say there were hurdles in the way:
- Draw in Autocad - done
- Print 1:1 on my local Laserjet 2100 - Autocad says it's done it - printer stays awfully quiet. Much mucking about and I find that t he printer has lost it's IP address in the recent power cuts - pinging 192.168.1.69 where it should be returns nothing. OK what's it set itself to? I know that it's physically connected to the hub as if I unplug it the appropriate light goes out on the hub. There is a way to print out Laserjet settings pressing a combination of buttons on the printer. A bit of googling and I find it's now 192.168.1.224 - quickly set the printer port to this and I can print out the sketch:

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and mark the pipe:

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OK lets cut some steel - no apparently there's a water trough at the far end of the field gushing (expensive) water and needs immediate attention so of I go 

Suitable bend put in the float valve rod and we are back. A few cuts in the pipe end - break off the unwanted bits and let try it . Now I'd left the sticky out bits long knowing that they would need a bit of a bend to fit - offer it up, a tap with a large rubber hammer and the tabs go in the nut recesses remarkably well.


First attempt at unscrewing has failed as I can't stop the axle rotating as I apply torque - I'm using  the 'leather glove and welding clamp' well known method but it slips too much.

Withdraw for a rethink as I'm blooming cold having been playing with water and need to warm up.

John, photos later as I'm occupied elsewhere atm but I came across an off cut of the Steam Pipe that Pete got for me to use as an extended exhaust pipe for the big 110 kva generator that I use to run the Induction Furness.

Not an exact fit but if I make the engagement lugs somewhat longer than needed I 'think' I can bend them to engage properly

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Just a bit more progress: I've managed to extract the stub of that M12 Countersink headed screw by jamming a Torx bit up the hole that I'd drilled and using the Impact Gun:

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And I've identified the  bearing retainer nut that I need to unscrew from the shaft for the next step - It's a KM10 M50 x 1.5 mm pitch bearing lock nut - amazingly still an available standard. As this is deeply recessed it's hard to measure for making a suitable key, but fortunately it has KM10 stamped on it !

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Seems that I need a 100 mm length (minimum) of 50 mm bore x 70 mm o/d heavy walled pipe. My initial searches have drawn a blank here in the work shop.

(needs to be hollow to slip over the shaft and reach into the nut. The search continues. Theoretically I could turn it from solid bar but that a lot of drilling and boring !

I think I'd have reached for the TIG myself if that had been mine. Between the added leverage of a large bolt welded to the head plus the effect of heat, I'd be surprised if it didn't budge. But there's no right or wrong method.

Csk machine screws with hex sockets are one of the least effective and most troublesome fasteners - hard to tighten adequately without damaging the head and a sod to remove when they get clagged up after the passage of time and corrosion.

Yes- when you think that was just a splash cover the CSK screw was holding on, & the trouble it caused.