1200mmX900mmX170mm 4axis cnc

[Nickhofen]

Your project is going well !
Congrats !

I have some positive news..
Mostly ... In most-all alu designs/builds I have seen, little to no serious alu cutting has been done.
BUT..
You can later upgrade the machine stiffness, pretty easily, imho.
If You do need to, that is.
It will be perfectly feasible to drill/ream a few dowel pins, through clamped flats into the alu, and fix steel flats onto the sides of any beams.
And You can even fix them mostly by gluing .. if You use industrial epoxy glues.
And yes, they are strong enough, and no, they wont reduce rigidity.

As-is, I would not give any advice.
You have a pretty good path, and it is likely to work out very well for wood.
And with suitable parameters it will likely do some alu, with hsm toolpaths and smallish cutters.

But rigidity-needed is related to machine work-envelope size, esp. free-length ie the working length of your beam.
900 mm is pretty big.
A mechmate at 1200 mm beam is pretty close, and they are a near-professional tool, in steel, heavy and expensive to build.

In a nutshell;
looks good.
Likely to give great results in wood.
Well done.
Keep going.
If You need to, *anything* can always be upgraded.

Hi there.
Thanks for the positive feedback.
So if I understand right you suggest to screw or glue, in the future, pieces of steel on one side of aluminum extrusions for rigidity purpose? That sounds as a good plan!

[Nickhofen]

I place the order for the aluminium extrusions, it seems that something starts to happen with this build. :-)
Except for the higher noise level between air cooled VFD spindles vs water cooled spindles, is there another reason why not to take a 2.2kW Chinese aircooled VFD spindle? I found one aircooled with four bearings, shipped from Europe and the price looks good, to me.
I will post the link tomorrow when I get back home.

[Clive S]

I place the order for the aluminium extrusions, it seems that something starts to happen with this build. :-)
Except for the higher noise level between air cooled VFD spindles vs water cooled spindles, is there another reason why not to take a 2.2kW Chinese aircooled VFD spindle? I found one aircooled with four bearings, shipped from Europe and the price looks good, to me.
I will post the link tomorrow when I get back home.

The only reason I know is that if you want to run it at a low speed say 7K then the fan will not put as much air across the spindle so could possibly heat up. But for me a WC one is a no brainer

[Nickhofen]

The only reason I know is that if you want to run it at a low speed say 7K then the fan will not put as much air across the spindle so could possibly heat up. But for me a WC one is a no brainer

Thanks for the input, I hope I didn't open a can of worms with my question. ;-)