Cast aluminium repair job

[BrokenBiker]

My first proper cast ally repair.

Driveshaft housing off a planer thicknesser that spontaneously disassembled itself last night when a drive chain let go.

2mm cast Chinese ally, seems ok to weld, not great but better than I was expecting. Not as dirty as I was expecting at least.

1.6mm red tungsten, 1.6mm 4043 (because I can't find my 5356), 2mm casting thickness and a load of cracks/breaks.

The nub at the front on top wasn't needed so popped it off and patched over it.

Then end that broke off is unsupported for some reason, even though it holds a bearing and there's a fair bit of force through it.

Fit together as best I could and tacked up...but if crap floating about but nothing major surprisingly

Nub from the top removed, cracks V'd out and prepped to weld

Not pretty, but full penetration and washed the high spots down with the arc so no grinding needed

Mostly finished, decided to completely build up the section at the front where the nub was...

Now just need to tackle 1 more crack at the back end, then figure out how to reclaim the bearing seat inside as I wasn't careful enough and the top has sagged a bit

While this went well for what it is, I don't envy anyone who does this work for a living

 

[oldbikedavey]

Reckon that could be sand-cast in a zinc alloy ?
Just a thought.....

 

[Bsmith]

Jobs sound, I don't see anything wrong with your repair especially when you know that it wasn't normal use that broke it.

I have tig but no argon so I woulda been making something hollow from mild steel to slide inside, tap and thread for cross studs and have the end bored to bearing size.

 

[BrokenBiker]

Reckon that could be sand-cast in a zinc alloy ?
Just a thought.....

I'm not sure, sand cast could be a possibility, but it's a mass produced tool so more likely die cast I would imagine. It welded ok, just threw up more of a fight than 'good' Ali...this stuff isn't good by any means, it's soft as chocolate

Jobs sound, I don't see anything wrong with your repair especially when you know that it wasn't normal use that broke it.

I have tig but no argon so I woulda been making something hollow from mild steel to slide inside, tap and thread for cross studs and have the end bored to bearing size.

Thanks, there is a slight change to the plan now as the bearing seat needs to be reclaimed, and is either at the bottom of a deep hole, or from the other side it's behind a shoulder, but I've been told the end play is set from this bearing and it could do with being a smidge tighter so once the welding is fully finished I'm going to turn the shoulder back, fix the bearing seat then turn a large washer to weld back on as the shoulder...

It's an unobtanium part without buying a new complete unit, so if it doesn't work the outcome is a new tool anyway, so may as well have a go at it. My only real issue is going to be getting it set up in the lathe as there aren't any flat or square surfaces I can rely on, and the bearing seat bore and the through hole at the end are no longer round, but I'm sure the 4 jaw and a few minutes tapping it about will get it close enough

 

[Morris]

Repair looks ok, I've had castings that weld like that. I think I would have made a jig to maintain alignment for it though.

 

[BrokenBiker]

Repair looks ok, I've had castings that weld like that. I think I would have made a jig to maintain alignment for it though.

There isn't really anything to reference the hole position from the only decent fixed location is the bearing seat, which had broken off...everything else in the floats

I was always going to have to touch up the bearing seat anyway as hole repair on top is right above it and broken through into it

 

[BrokenBiker]

Still have some welding to do this afternoon, but threw it into the 4 jaw for a test fit and it looks like I have enough of the through hole left to indicate off and plenty of adjustment in the jaws to get it as close as it needs to be.

Further inspection of the planer has revealed the bearing that sits in this housing was bone dry, and very notchy, so now thinking that was the initial cause of the failure. New bearing on order, new chain ready so by the weekend should be able to tell if it's a successful repair