1 Topic by ITman496

  • ITman496
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Topic: Tornado custom CNC machine

So I've been making a cnc machine.  Honestly now after its all said and done I wish I had bought one, but meh.  Too late now.  At least mine is probably really rigid.

https://dl.dropboxusercontent.com/u/4963246/cnc%20machine/tornado/done%20parts/IMG_20150418_010746_774.jpg

https://dl.dropboxusercontent.com/u/4963246/cnc%20machine/tornado/done%20parts/IMG_20150418_010917_286.jpg


It has an interesting issue, though.  Despite having triple stack nema 34 stepper motors driven to freaking 5 amps, and a 54V power supply (with a volt meter on it and DEFINITELY enough amperage supply) the motors seem to be unable to move more then 197rpm. (500mm/min) with a 10 turns per inch leadscrew and 8x microstepping drivers.  The motors, not loaded particularly hard, even with pitifully slow acceleration, once they go past 500mm/min, they just stop and start vibrating.  Is it the drivers?  I'm using something called CW250 drivers. 5A 60v max rated. 8x microstepping.. I didn't think they were absolute garbage but..  Can anyone recommend anything that does more then a pitiful .33 inches per second? The machine is painfully slow.  How does one increase the max rpm for a stepper? I feel like they should be able to go faster then this. 

But maybe I'm wrong?

2 Reply by shields1.as

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Re: Tornado custom CNC machine

Turn the verf way up. The should also be speed settings in the software somewhere

3 Reply by ITman496

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Re: Tornado custom CNC machine

The drivers are already set to their max of 5A drive output current, and if I raise the software up any higher, the motors start to vibrate instead of rotate.  I think I was just a dummy and made a bad motor choice, they are too big.  Whoops! This is what I get for not asking people..

4 Reply by ITman496

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Re: Tornado custom CNC machine

Never let me make my own spindle again. ITS SO LOUD.

5 Reply by Tin Falcon

  • Tin Falcon
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Re: Tornado custom CNC machine

you may want to read this.
http://www.geckodrive.com/gecko/images/ … 0Guide.pdf

You may want to throw some bigger pulleys on the motors. that will speed things up some.
tin

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6 Reply by ITman496

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Re: Tornado custom CNC machine

that was a very good read, thank you!  I can see I have some upgrades to do..