Quite an Unusual one

[Boyan Silyavski]

Hi,
Now the question of the day is having in mind all the servos are 400w, do I drive all 1:1 or 2:1 ??? The x y encoders are 2048 and the z is 2500 ppr ,all the screws are xx10 and 1605 for the z
The servos will accept 100000 pps at step mode

[Boyan Silyavski]

Last revision. Can not find a weak spot that is not bombproof. Starts to look more and more like a mill .

1. Decided to drivel all 20:30t, only the Z is 20:20t. This after exausting 3 day calculations, belt lengths,inertia, tooth engagement, speeds, etc. and at the end -common sense.
This is a separate thread of its own. I believe this the wisest decision between speed, acceleration, precision.


2.I decided to redesign the Z as it bothered me, especially with this long 1400mm belt. At the end common sense also helped here. At the end raised a bit the overhang without compromising anything so much. I design like this-until i see perfection at every detail.

So the Z. Tried to design it like a Russian tank from WW2. All plates are 20mm Aluminum.

- it would be covered against dust from all sides



-The cheese . The additional holes at the front are for mounting extra things, like: 3D plastic head, plasma torch, engraver, light and so on. The front plate on the moving box is separated in 3 parts. The lowest one is for the case when a so high object is machined that the spindle has to be all in, hence from there access to the nut of the spindle. the second part allows exchange of the spindle. The upper one stays there forever.



-The linear movement and where is placed. I even decided against using it for the hammer. the idea of making a precision machine and the trying to brake it seems less and less attractive. So this one will make the other which will be purpose build 5-6 axis, but anyways as i have 2 ball screws i decided to fit them.



-Reinforced the motor plate, this will hold the drag chain too. The belt now is very short as i like it, no extra pulleys and 6-7 teeth engagement each ball screw pulley. So seems ok to me.






The rotating ball nut assembly. 20:30t hence 1.5:1 driven. Compromise due to common sense. At the end precision and power at the same time is the aim.

2048 encoder on the motor, so more or less 20m/min. I see on the motor specs that it can go up to 4500rpm, just the curve is straight till 3000rpm. The resolution will be ~0.003mm on all axis , 0.001mm on the Z/ 1605 screw and 2500ppr encoder/. That without any artificial gearing or micro stepping which is not needed it seems. Thats good, cause the Galil board is not micro stepping board.