8x4 router build. Steel base & Aluminium gantry gantry

[charlieuk]

I thought you had used those drives on another build? The rack and pinnion does seam nice on my build I have done but I was thinking that screws would be the way to go posable. if you have the drives already though then your half way there.

[D-man]

Yeah they are on the 4x4,it was a 3mtr but had to cut it down due to a large contract coming in and needed the space. ive now sorted the shop so that it would not get in the way

[D-man]

OK ive managed to get a little more done this morning before the wife started chewing my ear.

Fingers crossed if all pans out, i can have the frame uilt for friday and into powdercoat for saturday/Monday.

Im thinking about servos on the X & Y and a leadshine on the Z. any suggestions?

[EddyCurrent]

Best advice with regard to Z axis is to put rails on front plate, bit where the spindle mounts, and bearing blocks on back plate, i.e. opposite to what you've shown.

[D-man]

Is this to make it more rigid..? From the commercial ones ive seen they are all mounted like this. as i thought with it being the Hiwin rails with less play than the SBR stuff

I dont suppose anyone knows what this bar is for on the bottom of the gantry of the Techno machines do they? Im guessing that when its tightened it pulls it square of some sort?

[D-man]

Nevermind ive found ou what it is

"a special steel backing beam and torsion bar are integrated into the axis for added stability. The torsion bar acts like a sway bar on a vehicle, which in turn keeps everything straight and taut when cutting loads change. The steel backing beam provides extra support to the linear rails, greatly improving the router's rigidity."

[mekanik]

Hi D man
I would wait for conformation off one of our more experienced members but i would think the Z needs to be on the other side of the gantry so it is better centered over the X axis bearing blocks.
Regards
Mike

[D-man]

Yeah ive been thing about this myself, The setup works on my 4x4, however thats only cuttin MDF and light plastic. i have been toying with the itea of vertical ones on this one, but the side to side motion worries me as im not connecting the gantry under the table.

[JAZZCNC]

Best advice with regard to Z axis is to put rails on front plate, bit where the spindle mounts, and bearing blocks on back plate, i.e. opposite to what you've shown.

Normally Eddy I'd 100% agree with you but with such short travel then no I'd go with something like how it's set out now. Thou I would have the bearings on the front plate lower with next to no overhang and extend the spindle down in the clamps. This will give full support to spindle/front plate from the rear plate.
If longer travel then I'd set it out other way.

Derek I wouldn't mix servos and steppers and go with same on all axis. Not that they can't mix but it keeps electrics all the same and there won't be much difference in price. If your going with servo's or even steppers for that matter then suggest you get a decent motion control card. Definately will need one for servo's to get decent performance out of them.

[D-man]

Any suggestions pal? I had read a post where you suggestion leadshine and some tricked up card from the US but I can't seem to find the thread