Vexta 266-01b

[tekno]

hey, I found 5 vexta 266-01b for $22.50 each.. I was wondering if this is a good deal and if they would be good steppers for a router table


thanks

Tek

[Al_The_Man]

They are fairly small they are double shaft 3.6v 1amp/phase 125 0z/inch holding torque.
Al

[tekno]

I thought that the 125 /oz would be ok... I was thinking on a 4 to 1 or 8 to 1 belt drive

[Clyde]

I'm using the PK266-01A (no shaft on other end, but same motor otherwise) for my Z Axis, works great.

I have 3, but changed over to PK266-E2.0B (was 84.00 usd from oriental online) for the X and Y axis to get more torque at high speed (running them at 1800 rpm at 46v 2A w/gecko drivers, they can run at 2000 rpm).

Depends on the jog and cut speed you want to end up with, but they can work with the right setup.

I used direct drive with 1/2"x10 acme drive screws, this gives lots of holding/drive torque without gearing/pulleying down.

On the Z axis (where I'm using the PK266-01A) I've set the max speed to around 120 IPM whereas on the X and Y (PK266-02A) I have it set at 180 IPM.

I believe that the PK266-01 is rated at 1500 RPM, so you can calculate what your max speed would be with the gear/pulley ratio and the drive/lead screws.

[tekno]

how do you calc the torque when you have a 4 to 1 gear/pulley ratio?

[Clyde]

The final torque at the driven object (gantry or whatever) must take more than the gear/pulley ratio into consideration, what about the lead/pitch of the screw? (you could probably wag it by mutilplying x 4 for a 4 to 1 as an estimate for just the gear/pulley part).

You will give up speed for torque using pulleys/gears but can gain some back by using a drive screw with fewer turns (larger lead/pitch) but then that will bring the final torque back down.....................

[ger21]

Be aware that the above speeds are obtainable due to the 46V. If you run these at 12V or 24V as most people do you won't be able to go that fast.

[tekno]

I was going to use the belt drive system that I have seen here. I would rather have torque then speed. This unit will be for custom car parts for my car only ( friends maybe but not commercial ). As such I would rather have high accuracy then speed. I was also thinking of an encoder on each motor for a closed feed back loop. So will be looking for a Cam that can handle the closed loop ( onecnc xp? ) The panel parts will be no larger the 3-4 feet and some will have to be put on a brake and bent to shape afterwards. Some of the parts will need a 4th axis.

I was thinking of router table attachment the 4th axis. I have seen one online for 15k . I’ll find the link and forward if someone would like to see it.

Thanks for the help

Tek

[arvidb]

If you are going for closed loop control and belt gearing, then use servos and not steppers.

Arvid

[ger21]

Cam software like OneCNC doesn't control the machine, it just creates the g-code.

The only system capable of running steppers closed loop that I'm aware of is MAXNC.

You're building a 4ft machine to cut metal? If so I'd get no smaller than 300 oz-in steppers.