"DeusEx"

[mocha]

**
Firstly a big thank you to everyone who has shared their experience on this site. This project would still be a vague pipe dream without your generosity.

As mentioned elsewhere, I have a trip to China coming up in just over a month and I'm hoping to use that trip to bring back some of the biggest bargains.

The research continues at a pace although not as fast as the time is counting down! I've had a chat with the guy who has access to the heavy engineering part... His Abene mill looks like a beast, but it's bound to be really useful along the way. It does of course mean that the whole design process has to be done in a rather tight timeframe which is less than ideal given my lack of understanding of the problems. Targets are design finished mid October and running before xmas! ROFL!

After trawling what feels like a majority of the internet, the design considerations so far (in no specific order as this thinking as still changing too rapidly!);

DeusExCNC

Small A3+ CNC capable of working wood, plastics and some light alloy (slowly) budget around 1000GBP

Working area of not less than 60cm x 60cm x 15cm. Overall I guess somewhere around 80cm x 80cm(?)

Design to incorporate adjustable height bed, 0-15cm, 15 to 30cm.

Box section steel frame at least 25mm x 25mm - filled with sand (thanks JAZZ!) a bit like this one, (Is there a name for the high side design?)






In the above pic, along with some other changes I'm thinking that I'd add a third vertical under the top rails and possibly add a cross bar at the back roughly where the steppers are at the far end for better stiffness and also triangulate the bottom of "open" end. I have seen another similar design that uses a substantial C section for the top rail too…

20mm supported round rail on X,Y,Z haven't found a price for profiled, I expect it will be outside my budget.

This is the area giving me the most problems at the moment, currently from what I've read, I think I need;
Steppers - 23(?) 3nm? (still trying to play with Irving's excellent spread sheet)
Ball screws - X,Y; 20, 10mm pitch (approx. 800mm long) FFZD ball nuts
Ball screws - Z; 20, 5mm pitch (approx. 300mm long)

Construction
The top rails that mount the supported rail for the X to run on would seem to be the first construction problem and perhaps one of the reasons this is not a very popular design(?).

My plan is to Mig weld the end verticals (35 - 40cm ish long) to the top rails then clamp them to the big Abene mill and skim 10 thou or so off to level them up. Then invert them, clamp the machined faces to the table and weld the bottom part of the structure together. That should (I'm thinking) give me to flat and level and parallel surface on which to mount the supported rails. The "bottom" of the structure is sure to be less accurate and more uneven, so use car body filler to level it on the stand/ table with a laser level. Then finally, mill the spoil board level to the Z axis.

Setting up the X supported rails; build the Y axis, then set one of the X rails by eye and using the other side of the Y as a guide, fettle, shim and file for best fit of the Y, bolting down gradually.

Y Axis
steel gantry, design to be decided
Z Axis alloy, design to be decided



2.2kw water cooled spindle - (noise!) PC cooler mounted on Z.

Gecko G540, although the idea of a handful of the M542's / 752's and breakout board are growing on me.


70v power supply

Misc stuff:
vortex dust removal
"bitcam"
Z zero switch
Mist cooling.
temp sensors via Arduino


Still a thousand questions without answers, not least of which are;


Is the gecko g540 really worth the extra money for the fancy magic inside it??
If the Y axis supports ends up about 1m apart, whether to go with 2 steppers for the X or use just 1 and belts?





Any thoughts, suggestions or eggs most welcome! :-)