sliding gantry or sliding Base ?

[JohnJ]

I am still not sure about the steel box section yet, because when making a rectangular frame out of box section, the areas of the 4 sections touching each other, are rather small, i am not sure if the epoxy would be strong enough when the contact area is so small.

Nevertheless, i got round making a first design of the gantry it self, the Z Axis is just thrown together as of now, i dont like it either :)


I used 40x40 Aluminum Profiles, the "Spindle Base" is a 20mm Aluminum Plate.


The other plate is also 20mm Aluminum.


All Components used are from zapp, Y and Z are SFU16 Ballscrews with 5mm pitch, the rails are TBR20.
The big Profiles are 120x40 both.

I had the design in mind, that was chosen as the most rigid one in the "heavy duty design" paper, regarding the orientation of profiles,
as well as the orientation of the Y axis Rails.
The Assembly, as pictured, weighs in at 38kg right now, without stepper motors, only the parts you see.

For the profiles i would use ITEM profiles, as I know them well, because we design dust covers for our products using them at work.
I would use the heaviest option of profiles, ITEM has to offer.

Further plan would be to space the gantry up, as far as necessary to reach the workpiece height i desire, by using another two 120x40 each side, reinforce it by 45 degree pieces inwards, little bit restricting the workspace, but obviously useful.

And then creating a base, either chunky 60x180 Alu Profiles, or as mentioned, steel box section,
just rectangular , reinforced by 45 degree pieces and cross beams, with two TBR20 Rails and one Ballscrew for the X Table.

What do you think ?

Regards,
Clemens