The Cube and problem of picking motors

Hello All

I've been making a differnt kind of reprap (a repstrap?) for a while now, and ive got the frame done (in pic attached or ) its one meter by one meter by one meter, 8mm thick angle iron.

I made is this solid becouse i wish to try some milling with it etc etc. Ive got to pick my motors now and i was hoping for some advice, I was going to try and go for some intigrated controllers which can be daisychained by rs232 meaning I can directly hook them upto a pc and forgo any other processing. So although im paying extra for the motors i can save on the processor endstops encoders etc.

The problem is I have no idea what kind of wattage/ampage or torque i would need, I was going to get four stepper motors three for the axis's and one for the feed ( i know i could use a DC for the feed but I might try and work out a way where the power for the feed can be used for differnt interchangeable heads ie grippers)

So any advice would be most highly appriated, Theres two sites im looking at ,
[animatics.com]
[www.jvluk.com]

Thankyou for your time

NoZ

Edited 1 time(s). Last edit at 06/29/2009 07:25AM by Noz.

RS232 isn't intended for daisy chaining, for that, the equivalent spec is RS422 or RS485.

USB or ethernet are the more modern equivalents. Some of the newer designs are coming out with USB, I think Zachs does, and my design has USB, RS232 and RS485, but I'm still writing the software for my design.

Practically, a lot of people seem to be spending around 7 parts designing to 1 part building, so it may not be as big an issue as you think, unless you are working on simple items and need high productivity, or have a team of designers.

If you are after multiple copies, it would be cheaper to run multiple extruders on a larger frame, all linked and printing plastic in synchronisation.

Graham.

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My CNC/extruder creation: [grael-minifactory.blogspot.com]

... there are some 'intelligent motors' at nanotec: [en.nanotec.com]

But it could be easier to start with the gen3-'5D-controller' or an Arduino Mega or Quadruino/multiArduino and common stepper-drivers ...

Viktor

first my idea for a large work area is not to make identical copys really but so i can make large items, I can always make a smaller item than your work area but never a bigger one. So i thought im investing into so i'll try to do the best i can. Also im going to try milling and drilling etc so the more sterdy the frame the better.

I'm planning to have multiple heads with a self screw drive, so clockwise the arm can interlink into a head and when fully inserted it can then drive whatever the head needs but then if running anticlockwise it can unscrew itself and go onto anouther head. This is planned in the future but before i expand i need the core bits so i can make the extra bits.

im a little concerned that for the sake of a shoe the king falls type of thing, spending £50 more now might save me £££ later, if you know what i mean. This is why i thought i would go for a intigrated motor.

Thanks for the advice

NoZ

Funny! since about august of 2008 I have also been building a 1 meter cube, out of 80/20 aluminum extrusions I just started a blog to document it

you may wish to look at this:
[robotsshallrule.blogspot.com]

[www.pdjinc.com]