Tube bender - final(?) assembly and testing

Enough buggering about with the Bantam CNC lathe. Let's slap this tube bender together finally and see what we've got.

The final piece of the jigsaw to make up was this end cap, intended to prevent the ballnut travelling past the end of the ballscrew, at which point it would liberate most of the contents of the ballnut. Well my balls already dropped some time ago, so there would be no need for that.

Fits on the end of the ballscrew, held on with an M10 bolt. I could probably shear it off by applying large torque and negligible talent but at least it would offer some resistance / protest by way of warning in the process. Here's the ballnut (moving) end of the assembly:

And the fixed, thrust bearing end:

Assembly of the ballscrew parts was pretty straightforward once I'd genned up on how to put the main mechanism together again.

There's actually an optional hydraulic actuator that looks fairly similar to my ballscrew mechanism. Ballscrews don't like bending moments being applied through the ballnut though, hence my ballnut bracket pivots are aligned with the ballscrew axis, unlike this piston which doesn't give a toss:

Obvs I will be substituting my new ballscrew gubbins in place of the original ratchet mechanism. Like this:

A drill driver with a 17mm socket is the means of driving the actuator. Hopefully this will have enough grunt to bend 32mm x 1.5mm tubes, otherwise I'll have to use the beefier impact socket driver.

Bottom line though is - does it actually bend tubing ok? There's only one way to find out. Here's a length of 32mm dia tube, 1.5mm wall thickness loaded up.

And although I have established that a flat 3Ah battery bogs down, a charged 6Ah battery sails through. No need for the larger impact driver at this stage.

Not bad, not bad, although as before this thin walled tubing tends to collapse on the outside of the bend. The thicker walled tubes don't seem to suffer from that. However, I've got a selection of U bends and small radius mandrel bends to work with, so this isn't a massive problem. I will be fabricating the manifold using a series of them welded together.

Well, that was as much an exercise in learning the new conversational controls for the Linuxcnc Probe Basic Lathe GUI as it was fabricating the ballscrew actuator. Job done on that front though. I'm pleasantly surprised that it seems to have gone without any major cockups - as far as I can tell so far, although that can change.

The exhaust manifold can now wait for the next unnecessary tool that will appear in the overcrowded workshop, namely one of those trendy laser cutter / welder / cleaner. Unlike every Youtube influencer and his dog, I'll have to pay for mine but I won't be seeing that for another month or two (slow boat from China etc), so I'll revert to some of the other myriad unfinished "projects" I started but never quite finished, ideally some of them actually in the workshop.