Altmill 4x4 with ATC with 4x8 pass through

Community Discussion đź“„ General
1

Is there a way to setup the Altmill with a ATC while also having the ability to be able to slide a 4x8 sheet (pass through) ?

I want to tile a 4x8 sheet and use ATC

2

Not that I am aware of…

By themselves, pass through is easy, and ATC is getting easy. Putting them together, you run into that old physics conundrum of two objects trying to occupy the spot in space-time, and find that either the 4x8 won’t fit or the milling bit eats your ATC.

Possible solutions:

  1. Change the universe: Sienci could add 4-5 inches to the width of an AltMill Mk3 to make room for both a 4’ wide workpiece and (for example) a ~5" wide RCATC. While this would raise the cost of the AltMill, this feels like the simplest, least expensive and most reliable generalized solution, and would be one that could work with both RapidChange and Pneumatic changers. Please, Andy?

  2. Leverage Einstein and break the bonds of space and time: Either the workpiece or the ATC could be made to swap places on demand, so that the workplace is there while milling and the ATC is there when changing tools. It is unlikely you would be able to automatically move a 4x8 plywood sheet precisely and reliably, so the focus turns to creating a movable base for the ATC unit that can swing in and out of the 4x8 AltMill cutting area on demand without obstructing the pass thru capability or the Y-rail movement of the gantry, all while retaining the registration and precision needed to locate/load/unload the tools. This is starting to feel overly complex, but let’s slog on…

    If you weren’t doing pass thru, but only required full 4x4 material access, the ATC magazine could be rear-mounted on some sort of sliding shelf that would slide in and out from the back over the top of the workpiece. With pass thru, some sort of pivot/swing or bridge would have to be constructed that would support the whole cantilevered shelf above the 4’ wide workpiece. This would require more servos/steppers/pneumatics to move the shelf in and out…

    A suspended ATC unit would be subject to all the machine’s jerk forces and would need some serious engineering to ensure repeatability, but in theory it should be possible.

As the physics textbooks often say, practical application and demonstration left to the student.

Have fun - you aren’t the only one wishing for an affordable solution!

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3

I tried putting my ATC below the level of my spoilboard.
Problem then is you are at the extreme reach of your Z plunge.
Speaking of which, nobody ever answered my question:
can you run the spindle right off the rails if you go too low?
It was so close, I dared not test it.
Now that I’ve got my ATC working, I’ll look some more.

4

Instead of pushing through in one direction, does your design allow for the sheet to be rotated 180 degrees and set back on machine with the overhang on the same side of the machine as the first operation?

When I had my first cnc with only a 16” cutting area I often rotated the board in order to cut longer pieces.

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