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Dear All,
I'm going to make CNC machine prototype - I need it to be closed frame because that will be easier in the control design because I'm going to use servo motors instead of stepper motors
So I need closed frame design that i can build and apply the control I will design on it
Any help is welcome, I mainly need small mechanical closed frame design
Thanks everybody
What do you mean by closed frame ? Is it like a commercial machining centre with an enclosureQuote:
Originally Posted by ammaratef45
Also steppers are very capable - do you need servos?
I need servo cause i want to test control theories - it is graduation projectQuote:
Originally Posted by routercnc
I need design ready and tried cause my major is not mechanical engineering and i need this task (mechanical body) to be easy
And finally closed frame word is not my own description
I got it from book >> this is the chapter described that part https://drive.google.com/open?id=0B1El2XHLhbSCU1hYX1hTbUZfeVE
Any clarification will be helpful
I really thank you for your reply
OK. So a 'closed frame' is a 'fixed gantry' and an 'open frame' is like a conventional milling machine.
Good example of a 'closed frame' here, first picture in post#1
http://www.mycncuk.com/threads/9616-...d-that-be-Zeus
But there are not many fixed gantry machines on this forum, most are another type with a moving gantry to cut bigger pieces. But have a look through the build logs:
http://www.mycncuk.com/forums/253-DIY-Router-Build-Logs
Sorry I'm confused here, But i think the gantry is moving in the picture provided in the link! isn't it?Quote:
Originally Posted by routercnc
Hi,
The gantry is the large fixed frame connected to the bed, in the shape of an arch. It does not move.
The X axis carriage moves the Z spindle plate left to right on this fixed gantry.
The Z axis spindle plate moves the spindle up and down
On the bed the Y axis plate moves the workpiece left to right.
Hope that helps.
Attachment 18939
Here is diesel's [closed frame / fixed gantry] machine:
http://www.mycncuk.com/threads/8510-...t=fixed+gantry
Here is Wals' [open frame / mill style] machine:
http://www.mycncuk.com/threads/7001-...t=fixed+gantry
(If you are going for max performance then use profile linear rails (Hiwin etc.) not supported rail.
The way i see it your best bet is to make a simple fixed gantry machine from aluminium extrusions like the one at the picture bellow
Attachment 18940
And maybe make it more miniature and enclose it like that:
Attachment 18941
So at the end you finish with a benchtop CNC.
My advice is thought to use at least round supported rails /SBR, TBR..20 size/ , even better, Hiwin 20 / much more expensive and better/ and 0.8kw water cooled spindle. Use also 3nm nema 23 motors and Am 822 drives, PSU for motors non regulated at 70VDC
I mean when you will be spending money make a real machine that will later have some value. Otherwise go ultra cheap all in one board with drives, 24v motors, PC ATC power supply , nema 17 motors. A micro CNC, similar to 3d printers. The middle way between what i am suggesting, is to spend your money for nothing.
That is awesome clarification .. Thanks very muchQuote:
Originally Posted by routercnc
Thank you very much .. can I find CAD file for design like you posted?Quote:
Originally Posted by Boyan Silyavski
GRABCAD is an excellent place to search for something.Quote:
Originally Posted by ammaratef45
Attachment 18950