2nd CNC purchased for dedicated use?

[Larry Schweitzer]

Most commercially made routers use rectangular tubular steel for framework. My machine has a moving table design. Less mass to move than the steel gantries but takes more space. Linear rails/bearings need to have frequent lubrication. Mount them is such a way that chips don't fall on them. Ball screws are universally used for the Z-axis, sometimes for the others also. My machine has them on all axis. Some machines will use the cheaper helical rack & pinion. Ball screws can be adjusted to provide almost no free play. Much harder to do with rack & pinion. Machine the top of the table in place with the router spindle. 

Are you using a PC for a controller or a real controller? Will the control incorporate a look ahead function so the momentum doesn't cause overshoot? Steppers or servos? Will you install reference pins? How will you dissipate the energy to slow the feed? How many lines of code will it look ahead with? Will the control have helical interpolation? Will it be able to move all axis at the same time? All these and more affect what the machine can do, how fast and accurately. 

[4DThinker]

I'm using ball screws and linear rails on all three axes.  I started with a tinyG controller and steppers from an unused X-carve kit.  I have the whole CNC assembled, and it turns out the steppers don't have enough torque to turn the Y axis without losing steps.  I bought larger steppers which I thought would work but the tinyG doesn't have enough oomph to turn all three axes (4 steppers) at the same time without complaining.  I like the tinyG as it has great acceleration/deceleration routines built in, but apparently isn't powerful enough on its own.  So I'm stalled at the moment.  I need a controller+driver combination, preferably something with included controller software.  

 

4D

[4DThinker]

Another old thread of course, but we did buy one of Probotix' newly upgraded CNCs for our small CNC room.  The old shark was moved out to make room for a Probotix GX2525.   I've put it on a taller stand, and replaced the MDF top with a version of my angle jig that when horizontal fills up the entire cutting area.  I can also lock the jig firmly in place when horizontal.  The new CNC design has a stiffer gantry beam, and more Z axis travel room above the bed.   The taller stand has come in handy several times, and I've had to add 3.5" to it using 4x4 blocks to do one job.   

 

4D

[difalkner]

And the photos are where...?  Otherwise, it didn't happen.

 

David

[4DThinker]

I posted this photo on routerforums.com. Jig in the vertical position.  At the time this photo was taken I hadn't yet put in the two parts that lock the jig in the horizontal position. 

[difalkner]

Ah, yes, I remember that now.  Thanks!

 

David