MetalworkingFun Forum

A lot became chips Tom. They supplied the material, the flanges are about 4 3/4, the stock was 5 5/8, but the bore was close.

And bronze is fun to machine.  Not long before I was discharged I was making some wear rings for a centrifugal fire & flushing pump, about 10" in dia.  There was this new ensign who had been made the quality control officer who wandered from shop to shop tending to get under people's feet.  Well I'd ground a 1" sq MoMax turning tool to throw the chips to my right.  I set the lathe (a 16" Pacemaker) to take a .500" deep cut and engaged the feed as he was standing next to the tailstock.  Just before I did so I caught the attention of the Leading Petty Officer (leadman) and he saw what was about to happen.  The look on his face was a Kodak moment.     The shower of hot bronze chips had its intended effect.

Well I was discharged less than a month later and had not seen the ensign since that day.    

Chalk one up for the enlisted guys.

Another time-consuming job on the tractor; the front axle kingpin bushes all needed replacing, as I posted the other day I needed to cut through them with the shaper to get the old ones out, once the new bushes were pressed into place, the top ones had squeezed down too tight to take the spindles. I don't have a reamer of the appropriate size (frustratingly I have one big adjustable reamer that comes up about 1mm shy of the required diameter) so I decided to set up in the mill and bore the bush to size.
Not enough Z-axis headroom under the vertical attachment on the U2 so I had to tram the attachment to horizontal and use the X-axis.
Turned a spigot to take the far end of the workpiece and centered it on the big angle plate using a small dead-centre in the drill chuck.
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Positioned the workpiece over the spigot, used the outside taper of the drill chuck to get the working end centered and used a bunch of machinist jacks and clamps to hold it there.
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I've thought a few times that I have acquired too many machinist jacks and I should flog a few off on eBay. This job changed my mind on that.
I've really got to get myself a decent 1/2" boring bar for the little chicom boring head, the only 1/2" boring bar I have with enough reach for this task is part of one of those miserable brazed-carbide cheapy sets that come in a wooden block. Got the job done though.

I'd be interested to know how the more experienced machinists (i.e. everyone) on here would have approached this job.

I'm waiting on seals for the stub-axles so couldn't get the outer front axles finished today, so I moved on to another part of the tractor and achieved a major milestone- got the gearbox re-mounted.
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CONGRATS!

Your set up looks good and was well thought out & executed.    The only other option I can think of off the top of my head would have been to line bore it on a lathe.

Don't know how you would have done it any differently Pete, with what you had at hand. Excellent adaptation!

Tom

Well done Pete. Now I need to buy another mill, thats incredible how the head will swing.

A while ago I bought a NOS Williams threading tool, posted a picture of the tool holder I made to mount it. 
Finally got around to trying it.




The head is a little large so it may be a problem at times working between centres but overall its great. Easy to sharpen, just grind the top flat and a light hone. It seams really stiff, a spring pass did virtually nothing in this setup where the part was rigid. That is as cut, didn't have to remove any burrs at the top of the thread.
 Wonder if they made other cutters with different front radius, this one is quite rounded so may not work for fine threads.

I've done a similar operation (only once) on my horizontal but on a MUCH smaller and much less awkwardly shaped part, great job of creative thinking !

Another useful application for a horizontal mill is to use it as a lathe. Works well for large faceplate work + brake drums, connecting rods, flywheels, anything that your normal lathe won't swing and is not too long.

Took a couple of hours and slapped this together. Hint: it's a metals rack. Still needs paint and probably a couple of things to stop the pieces from falling off the end but for now it'll do.



It's only 4' tall, mainly because I don't have much of anything longer and the longer stuff lives elsewhere. This will also be sitting on an old lathe stand.