Machining the Multifix toolpost pillar

 Aha! I behold a toolpost pillar inside that block of stock.

It's a piece of 6082-T6 that's a nominal 4.5" square and 86mm long. Ideal.

Toolpaths:

3D Adaptive to rough it out. Hopefully I have the balance right between reducing the machining time and not overloading the machine.

Then 3D Radial toolpath with 0.25 degree increment:

And finally a 3D Contour:

That little lot will take several hours but I'm hoping for a half reasonable surface finish.

Make chips:

I'm not going to convert the surplus 25mm or so of stock into swarf, so instead, I'll chop it off in the bandsaw. It's a bit too big for the blade but almost too short for the vise. This did the trick though:

I didn't time it but this must have taken half an hour or so.

Given the organic shape of the finished part, I need to have some means of holding it in the machine vise. So I added a couple of M10 threaded holes in what will end up as the base of the pillar, having faced it off first. Used the tension compression head for this and a toolpath generated in Fusion - it worked well. This piece of barstock is parallel to withing a few tens of microns, as I don't have much spare stock to lose in the X axis direction.

Here we are, set up with the Renishaw probe. 

Woah now, fat boy:

Some of the feeds and speeds felt a bit ambitious when I did an air cut. I'm trying to get this made before the sun cools down but my spindle motor is rated at around 3kW (4hp) which isn't exactly stump pulling territory. Thought I'd better check what my original values would require.

With 0.25mm per tooth (5 inserts per rev), 2000rpm and 5mm step down, I'd be needing almost 6kW, so the initial attempt would have been ahem fairly short lived. The machine time would have been about 1h for this, according to Fusion.

This looks a bit more achievable - 1800rpm, 1800rpm and 3mm stepdown, resulting in ~2kW:

But regenerating the toolpath ends up with around 3h of machine time. Hmm. Let's try to shorten that a bit. Perhaps whop the stepdown up from 3mm to 4.5mm? Yes, that takes it down to 2h on the dot - if the machine can handle it.

Reducing the fine stepdown to 1mm (from 0.45mm) removes another 22 mins. Given that I have 2 subsequent finishing passes (Radial and Contour), a slightly rougher 3D Adaptive shouldn't be an issue.

Let's give this go and see if it can cope with these settings. The motor nameplate claims 3.2kW at 1800rpm, so you never know....

Making chips:

Hmmph. The Yaskawa V1000 VFD reports the output power (in kW) when you set up monitor U1-08. However, the displayed value never exceeds 0.28kW or so. Not sure which to believe but generally Yaskawa stuff tends to work as advertised. Also not convinced The Shiz is actually breaking any kind of sweat. 

Bollocks - I've started, so I'll finish. Both the Fusion and Centroid time estimations are very similar (around the 1:20 mark), so I'll continue as it is. I could perhaps play with the settings to increase the spindle load but in the end I'd probably lose any time saved fannying about in Fusion. 

I have 22k lines of code, which is hardly a monster. 

First, this is going to be messy, so I'll fit some simple screens to contain the chips and coolant:

Then off we go:

Starting to emerge

I'm hardly pushing the machine here...

Starting to look fairly convincing....

I can live with this:

Took 1:36:22 according to Centroid. Nice result. So next I will apply the radial toolpath...

Sorted. Nice:

Drill bolt holes:

That worked for me.