3D Pantograph for Extruders


3D Pantograph for Extruders

There's no reason why you won't use the 3D Pantograph to replicate objects in Additive manufacturing (extruders), just as you do on Subtractive manufacturing, i.e. milling a block to shape.

The probe that “feels” the Original Object's shape, acts as a guide, to the moving setup, and that movement, going around a section of the object, makes the replicated object.

It's a 2-piece deal for complex shapes, thus the Original is rigidly secured, by pins, on a 180º rotating frame.

In the above illustration, the setup, where's the probe, the extruder, and the vertical set movement, move around, but won't rotate, because it sits on an array of 2 pairs of linear bearings.

The extruded plastic is set on that setup's motion, either manually, or by some purely Mechanical, or Arduino servo rig, flexible spiral motion set-up, and at a extruding level's completion, the vertical arm moves one pre-set height (the extrusion height) unit up.

But you've probably guessed the trade-off;

This works for an exterior “shell” build-up, good for many cases, but not for all!

The solution?

The probe can be tipped 90 degrees off, for a filler pattern, inside the already made contour, then set up again, on a rigid spring and ball 2 position precision mechanism.

Some edge detection, the edge being the contour already extruded, electronic gizmo has to be inserted, if the thing is to be automatic.

It is not hard to design such a Replicator, and so, a much cheaper Object creation machine can be produced, either as a low-cost alternative, as a Makerbot add-on, or as a mass-production set-up, for repetitive work robots.

You know, put the original in place, wait for the reproduced object to be made, do it again, etc.

It has a few things to be optimized, for automatic reproduction, but for a manual machine, it can be made today.

A final note:

This can serve many purposes:

-First, of course, for replicating original pieces;

-Then, for a kind of "sketcher", where you can nail some wood bits, and see it be made into a single ABS piece, so you can see it at work, and amend it on 3D; 

-Add one of the new 3D extruders, like Makerbot to this outfit, so the active extruder moves the replicator, presto! 2 or more extrusions at a time!

Makerbot, now even has a conveyor belt, so it's n extrusions times x conveyor belt repetitions!


I've made this 3D Sketch, you make a Siamese, Makerbot-Replicator rig, where the x and z moving base, blue, is linked to a simple set-up of 2 pairs of linear bearings, the y moving extruder holder, yellow, moves a slave extruder holder, and the conveyor belt add-ons, red, move the pieces made into the buckets.

Twice as many pieces, at the same time!