Machining square holes in a lathe

[woodfarmer]

Working on my latest product I needed to machine a square (oblong) hole to make a frame. My trusty Holbrook did not let me down

 

[novocaine]

top one's the wrong way round.
nice job.

no other tool in a machine shop is as versatile as a lathe. everything else does a one or a few jobs, the lathe does them all.
it's also the only tool in a machine shop that can build a version of itself with no other tools (excluding the nut behind the handwheel).

Next year, new roof on the workshop then I'm hiring a van at last and going to collect my lathe.

 

[Bod]

Alright, I'll ask...
How was it done?

Bod

 

[woodfarmer]

Ok I admit it, I did use a saw to cut it from the round bar that was hollowed out.

Hope this makes it clear

 

[Bod]

Thanks.
It's simple when you know how!
You had me puzzled, I was expecting vary special cutters.

Bod

 

[AndyT]

Nice one!

There's a similar trick you can do with a bit of thick leather - you fold it in two, clamp it between two bits of wood, then drill down through the fold. Open it out, you've drilled a square hole.

 

[woodfarmer]

Thanks.
It's simple when you know how!
You had me puzzled, I was expecting vary special cutters.

Bod

It took me a while to figure it out. Ideally I should have had a milling machine. Or maybe forged it, but I didn't trust my heat treating skills for this as strength is critical. Also can't weld anymore so this seemed the only (but tedious) option. Notice that the round bit at the end has a stepped recess inside. This is for an endcap to fit into so I have frame in the middle.