Just started putting together an 8020 router for wood, aluminum, etc.
Was hoping for around a 40"x60"x8" cutting envelope. Probably will end up with 36ish" x 50-somethin' x 8" which is plenty large for me.
I originally planned on tig welding a 3"x3" tube steel frame, but getting it into my basement would be a bit problematic. I go into the build knowing that 8020 isn't the stiffest stuff in the world, but will make every attempt to reinforce the frame. Plus it's super easy to break down 8020 and transport it.
The frame is a bit over sized for my components. However, since the 8020 in the 3060 profile is so expensive I hoped to splurge on longer lengths than needed *once* and be able to reuse the profiles in other projects. I chose to leave the 3060 width of the machine at 48" rather than chopping it down to accommodate my Parker linear actuator. I'm going to use 1/2" plate at most of the joining points in order to make it as stiff as possible.
I'm going to try and drive the gantry from the side with an existing short ground ballscrew and see what happens. I have a 750W AC servo on hand, but I really surprised at the oomph of the 400W'rs. This would let me add another leg in the center of the long span and cut down deflection to almost zero (it's 0.0007" with a arbitrary 75lb center point load with a 70-something span in 3060 profile). Eventually I want to drive the gantry with a monster 2" diameter nut-driven screw that's 76" long.
* 8020 3060 profile frame, overall frame footprint ~54"x78"x40"
* 8020 3030 legs with leveling casters
* 66" Length THK HSR35 linear rails for gantry
* 48" Length Parker linear actuator for Y and Z axis (got for great price an industrial auction a while back). ~40" Y , 12" Z travel. Ground screws 5mm pitch on Y and Z.
* Mitsubishi MR-J2S 400W AC servo motors and drives
* Chinese 2.2kw spindle w/Hitachi VFD
* Rolled+Ground ballscrews (previous industrial auction finds). Most likely 5mm pitch for X axis, moving to 20mm pitch on giant nut-driven screw.
* Linux CNC driving Mesa 5i25 -> breakout board (forget the model #)
various pics:
Debating on whether the 40" is going to be TOO high of a working height. I'm only 5'8". Will have to play around with it a bit. Lots of time tapping/drilling holes ahead. Also need to add reinforcing plates below the frame.
Attachment 248268
Would rather side mount the rails, but will require extending the width of the gantry, as my actuator is mounted on 52" long 8020 and mounting on the sides would require an extension to ~58". Side mounting also makes more of the top of the profile available.
Attachment 248270
First step was making up some 3/4" mounting plates for the casters. May need to reconsider these casters as the rubber feet giggle around quite easily. Or add more solid feet later to anchor the machine to ground.
Attachment 248272
Attachment 248274