Inspiration is everywhere!

[chuckknigh]

Well, during my absence I've been thinking. Always a dangerous thing for me to do.

All of us want bigger and stiffer machines...with more capacity, etc, etc, etc. Except for those of us who want finer and finer control on the micro scale, but that's the exception, rather than the rule.

Well, I've been inspired. Or cursed...I'm not sure which. :-)

In my garage, I was looking up, and realized that the ceiling is a suspended ceiling. Remember...knowing it, and having it "hit" you are not the same thing. Inspiration happens in the strangest ways...

Whie looking up I also looked at my garage door opener.

Well, some of you probably can see where this is going. A VERY large moving gantry router, hanging from the ceiling. Let's see...a 2 car garage is 20x24', standard, and would need almost no clearance between the ceiling and the gantry. Hmmm...

I wonder if such a construct would be practical? If designed right, getting the Z axis "down" to a standardized work height would not be terribly difficult...and even as long as it would be, it wouldn't be a major problem to keep it rigid.

Hmmm...a "fold away" giant router that takes up no floor space. Might be a worthwhile project!

Let's see, a trip to an Overhead Door dealer (5/8" ACME screws, rails, and limit switches) and a good portion of the moving gantry is done! I love off-the-shelf parts. I wonder how rigid it could be made?

Let the discussion commence...

Muahahahaha!

-- Chuck Knight

[Mr.Chips]

But how about the precision of that 5/8" ACME screw. I always hear that the screw and its precision is critical?

Yeah, My Gene grage door operner has a screw also.

Hummmmmm

[chuckknigh]

I'm not sure, but how bad could it be? I mean, most of us aren't making parts requiring accuracy to the micron, anyway... :-)

I assume that a router on this scale would not be used to inlay delicate parts, where accuracy to .001" would be required. Reasonable accuracy for woodworking, etc would probably be in the neighborhood of .01"...better than we could get with most tools, other than a mill. And I think this is probably achievable, given the relative mass and rigidity of the ceiling.

I'm talking about a 20x20' router that would actually FIT in the average garage workshop! YEEEAAAAA! (My Howard Dean impression) Even if it was implemented only as 2.5D, it'd still be a most excellent unit, and a heck of a lot of fun.

My primary concern would be the rigidity of the boom on which the Z axis would be mounted...not insurmountable, but definitely worthy of consideration. A little triangulation, and it shouldn't be a major problem.

Remember, leadscrews can always be upgraded...the basic structure has to be sound, first.

-- Chuck Knight

[anoel]

What ever happened to your Tetrapod/Hexapod/Rotopod thing you were working on? Get anywhere with that?

[Mr.Chips]

I agree Chuck.
When my garage door opens it generates lots of sound.

If I mount the Z Axis to the garage door, I automatically get a 4 axis machine. Think you got something.

Post pictures.

Hee Hee

[Hobbiest]

That garage door screw is 5/8"-10 acme, and actually not too bad! My friends and I built a machine using it once. Not precision, to be sure, but it also has kind of a fun thing, a groove in the peak of the thread for oil. I think that is kinda fun anyway, course...I'm demented as it is! You can get take out foor openers for free a lot of the time, we got three at the dump. The screws are about 8' long too. Watch out for the new door openers though, they use two four footers for the screw, and will only join in the track.

[balsaman]

Chuck, did you ever get drivers for your machine?

Eric

[cnczane]

I like it because it means you can carve things LIFE-SIZE...

[chuckknigh]

I have driver boards, but I've not dedicated the time, yet, to fix the bug. They each work individually, but when all hooked up at the same time, they don't respond. I probably have a wiring error, or something, and I just need to spend some time with it.

I'm just outside of Dallas, so it's cold and wet right now...hardly ideal for spending time in my garage shop.

As to the rotobot, it's more a thought experiment than anything else. A fun project for "someday." I'd like to build one, but probably not right now.

-- Chuck Knight

P.S. I have 2 garage door tracks, lying on the deck in the back yard. Hmmm...might be a good start!

[cnczane]

For that matter, why tracks at all? What with GIS, you could put some XYZ smarts on your bot itself and hand it a router...

[chuckknigh]

GIS? I don't know what you mean...what is GIS?

-- Chuck Knight

[cnczane]

I'm sorry. I confused GIS, Geographic Information Systems, with GPS, Global Positioning Systems.

Putting GIS on your robot would be equivalent to handing it an atlas, but I intended that, with GPS, it could "know" its location in XYZ at all times from the satellites. I always wanted to build an outdoor plotter like this.