New member from South Africa

[mitchejc]

Hi
I'm James Mitchell, a 47 year old computer programmer from South Africa. Thanks for all the great info here on myCNCUK! Decided to take the plunge and and build a rigid CNC router exclusively for cutting aluminium parts. I have a 2.1m x 1.4m x .15m commercially build router that I have been running for the last 5 years and I need (no, want :-) ) something better for machining aluminium. Something like a Datron M75 would be first prize but that's never going to happen so my specs/ideas for the build are something as following:

Cutting area: 600mm x 450mm x 150mm.
Linear guides & ballskrew (I have Hiwin 15HGH 900mm, 750mm and 350mm rails & blocks and 4 x Chinese 1605 ballskews so I'm going with that)
Expected performance: Speed is not a great issue and I'd be very happy with 4000mm/min rapids with decent acceleration and hopefully 1000 - 2000mm/min for cutting.
I'm really hoping for great accuracy and repeatability. Not sure how to quantify but lets say <0.2mm tolerance on smaller parts
Construction will be steel or Alu
Weight is not a big issue as I plan to use decent sized motors and drivers.

I'm a bit in information overload mode at the moment and I'm having a hard time deciding on a good design. Fixed gantry or moving gantry etc but I'll start asking specific questions later.

Thanks
James

[AndyGuid]

Welcome from another colony under the southern cross!
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I cannot recall many(any?) fixed-gantry builds on here, but these may help you make a running start:
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Deisel's fixed-gantry = http://www.mycncuk.com/threads/6516-Monster-fixed-gantry-router-for-aluminium-wood?p=48872#post48872
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Jonathan's moving-gantry = http://www.mycncuk.com/threads/6484-A-sufficiently-strong-machine
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Andy

[GEOFFREY]

Wellcome to the site. For your uses and the machine size I feel sure that fixed gantry is the way to go. Good luck. G.

[Clive S]

Welcome from another colony under the southern cross!
.
I cannot recall many(any?) fixed-gantry builds on here, but these may help you make a running start:
.
Deisel's fixed-gantry = http://www.mycncuk.com/threads/6516-Monster-fixed-gantry-router-for-aluminium-wood?p=48872#post48872
.
Jonathan's moving-gantry = http://www.mycncuk.com/threads/6484-A-sufficiently-strong-machine
.
Andy
Hear is a small very capable fix gantry machine that run very nice http://www.mycncuk.com/threads/7001-How-much-deflection-to-expect/page4?highlight=fixed+gantry created by Wal. ..Clive

[mitchejc]

Thank you much gents, I'll certainly have a look at those threads!

Considering the copious amounts of aluminium that goes into some of these builds I'm curious how much aluminium costs over there? Here its +- ZAR 75-00 per kg (EU 5.50/kg) for thick sheet type material. Specialized extrusions is more expensive and often sold per meter not kg.

[mekanik]

Hi mitchejc welcome to the forum
sounds like steel might be your best option.
Mike

[mitchejc]

Thanks, yep I really like the look of those nice alu machines but steel is likely to be my best bet.