Cnc adventure Vol.1

[Scustom]

Hi Andy
Yep,Aluminum plates,not steel,typing error.
Yes,that would be option 2,I would have to make a 15mm spacer to mount everything together.
Option one is preffered,since milling two faces would not cost a fortune,if I go with handcutting alu plates,and It would reduce overhang by 15mm.I’ve put 240mm long gantry sideplates versus 280mm you did.I’ll have to finish z axis (spindle and mount)and run center of mass analysis,so then I’ll see where I am,if is needed to elongate sideplates or not.
Well steel frame didn’t seem that big of a hassle.I’ll check both options!Thanks for that.
If alu is chosen,kiln dryed sand is an option if resonance and vibratins occur as Lee sugested.
Yes its a bit offcentre so when ballnut and mounting bracket are connected nothing is sticking out of that T bracket,but yes I can beef it up a bit.
Andy you used 2010 ballscrew,so do I in this stages,but did you consider 1610 and making it both sides fixed?Did anybody do that?Rotational mass would be significantly lower with 1610.��
Never went in calculating critical speed for 1610 in fixed fixed arrangement,but I will,just to see what would be results in comparison to 2010 ballscrew in fixed/supported arrangement.

[AndyUK]

Andy you used 2010 ballscrew,so do I in this stages,but did you consider 1610 and making it both sides fixed?Did anybody do that?Rotational mass would be significantly lower with 1610.��
Never went in calculating critical speed for 1610 in fixed fixed arrangement,but I will,just to see what would be results in comparison to 2010 ballscrew in fixed/supported arrangement.

I considered it, but went with the 2010 fixed supported as you say. From memory, the fixed-fixed didn't make that much difference to the critical speed (I'm too lazy to go re-calculate it now....). It also constrains the ballscrew mounting slightly more, and I didn't know if that would be a pain later on :)

You're correct it makes quite a big difference to the rotational inertia - but don't forget that the motor calculation spreadsheet has a factor of 3 as a safety margin. The implication is that I'm not overly concerned about that extra rotational inertia (because I'm quite confident my motors can cope with it to decent rapid speeds). That extra headroom on the critical speed means I should be able to push my motors further than initially calculated to find my max rapids without having to worry about whipping.

[Scustom]

Yep,doesn’t make much sifference,fixed supported gives higher max speed.
Can someone help me with steppers?
I’m planning to use lichuan hybrid servos,3phase nema 23 3nm on z and x and 2 phase nema 24 4.5nm on y.max rated voltage for 3 phase driver is 50vdc wich means 48vdc PS max.Calculating ideal voltage for nema24(since has highest inductance) ideal PS would be around 57vdc,so 48v is 16%less than ideal,what does that mean to max speed and torque output of the motor?
Is it better to go all axes 2phase and use higher voltage drivers and run them at 60vdc?
Can anyone help me,since I’m really strugling with this one..
Thanks