Fully supported linear bearings - Radial squareness

[Slixxor]

Hi Paul. Yes I have seen the page. I am planning on using a 2.2kw water cooled spindle. Z axis range of 300mm. My rails for Z are 450mm long. I am adding 45° gusset/supports to both sides of each corner of the frame. I will be running dual ball screws on the X axis to minimize racking each with their own nema34 34HS59-5004S. Still havent decided if I'll be using the same size stepper on Z just yet or slightly smaller.

I haven't done a cad example of my design for reference. May do shortly pending work commitments.

[Neale]

Sure that those Nema 34s are a good fit for this size machine? Nema 23 would be more usual and this is a situation where over-building is definitely a bad thing. I was talking to someone last night who bought someone else's project router and with Nema 34 ("bigger must be better") he was getting no more than 1m/min when with the correct motors he should have been seeing 5m/min or more. Big motors come with much more inertia and high inductance which are both speed killers. Might be worth a bit of investigation?

[Slixxor]

The bed size is 1300x1000. I am happy to run whatever I need in order to be able to mill aluminium comfortably. I opted for the 34's due their torque at low rpm. Can anyone suggest a nema23 suitable for the application, they certainly are cheaper :)

[Clive S]

The bed size is 1300x1000. I am happy to run whatever I need in order to be able to mill aluminium comfortably. I opted for the 34's due their torque at low rpm. Can anyone suggest a nema23 suitable for the application, they certainly are cheaper :)

nema 34 is overkill and won't work as expected try these https://www.cnc4you.co.uk/Stepper-Mo...YGH301B-Nema23 more than capable for that size of machine

[Slixxor]

Thanks Clive S,

you've saved me $420 AU. Does anyone else agree with Nema23 23HS45-3504S being the best choice for a steel gantry and Z axis?
that will likely weigh over 30kg?

[Neale]

I'm using these in a slightly larger machine, steel gantry probably weighs around 50kg, and I'm not expecting any problems. It's a very common setup. You do need to drive them with a suitable voltage - 60V or more.

[Paul3112]

Agree with 23's .. ball screws = 10 mm is ok (5mm better axial load deflection needs looking at )
I assume you are in Aust, so these links might be of assistance. Both are in Melb.
http://www.homanndesigns.com/
http://stores.ebay.com.au/CNC-AND-CU...=p4634.c0.m322
CHECK THE SCREW LENGTH This guy normally lists travel length ..

Paul

[Slixxor]

Thanks @Paul3112, saved in favourites. :)

This is the kit I ordered but had modified for my lengths: http://www.ebay.com.au/itm/331320314...%3AMEBIDX%3AIT

This is the motor kit I wanted to buy: http://www.ebay.com.au/itm/171994192...84.m1436.l2649
This is the motor kit I am considering now: http://www.ebay.com.au/itm/171937212...84.m1436.l2649

[lucan07]

My 1000x700 build uses Mema 23 425oz 3amp at around £20 each, and they plenty of torque and speed, forgot to change DOC other day set to 3mm 6mm 2 flute for MDF (cuts MDF 6mm 2 flute at 15mm DOC Regularly), so ended up slot cutting 5083 aluminium at 3mm DOC 6mm 2 flute 1000mmpm FR, stepper torque was not a problem and it cut without incident but was working harder than it would normally.