Re: Converting an AMAT25LV
Welcome to the forum Lloyd. My comments would be up the volts on the drives if you can 68V is a good number with AM882 or EM806 drives and it definitely needs to be higher on the nema34.
I take it you are using ball screws.
I have done the conversion on the WM18 and used 23s with belt reduction all round and it runs fine.
Good luck with the build
Re: Converting an AMAT25LV
Thanks Clive
I'm using drivers from CNC4YOU.
5.6A, 50V CWD556 for the 23's
7.2A, 80VDC or 60VAC CWD872 for the 34.
I guess that means my best bet would be to keep the 48v supply for the 23's and add a 68V for the NEMA34 then?
Re: Converting an AMAT25LV
Quote:
Originally Posted by
Lloyd Barnes
Thanks Clive
I'm using drivers from CNC4YOU.
5.6A, 50V CWD556 for the 23's
7.2A, 80VDC or 60VAC CWD872 for the 34.
I guess that means my best bet would be to keep the 48v supply for the 23's and add a 68V for the NEMA34 then?
That's the problem that has been highlighted many times on the forum with buying kits.
Personally I would change the drives and built a toroidal transformer type PS.
Re: Converting an AMAT25LV
Quote:
Originally Posted by
Clive S
That's the problem that has been highlighted many times on the forum with buying kits.
Personally I would change the drives and built a toroidal transformer type PS.
No kits here Clive, I prefer to choose parts/screw things up myself :wink:
Re: Converting an AMAT25LV
Go for 2:1 reduction on the head and you won't need gas struts etc.
http://www.stevenson-engineers.co.uk...20complete.jpg
Re: Converting an AMAT25LV
Thanks for the heads up on this. Have spoken with the motor supplier and done some further research.
P
Can I check my understanding. As I understand it (be gentle I'm, still learning this stuff!) running the driver for the NEMA34 at 48v is going to generate a much lower torque. Rather than the 8.7nm its capable of, it's probably going to be running somewhere closer to 4.5-5nm. Speed however shouldn't change? Is that right?
P
Assuming I'm getting this right, then my options are to belt drive the motor to the ballscrew 2:1 thereby doubling the torque if halving the speed, or up the voltage to the 34 to something closer to the 80v the driver is capable of handling. Rather than rip apart everything I've done, I could add another PSU running 68V and hook that into the NEMA34 driver. As a bonus it would free up some load on the 48V PSU if I ever wanted to add a 4th axis.
P
I added the 34 to cope with the added weight of a future power drawbar, but you guys are running the Z axis on 2:1 geared belt with NEMA23? Are you saying the you need closer to 8nm to happily run the Z even without additional weight on it
P
Just trying to understand the problem and my options going forward. Have to say there is a tonne of information out there, some of it conflicting. Reading through various sites I've seen people converting the G0704 with 4nm NEMA23 direct driven to the Z.
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Re: Converting an AMAT25LV
Made some progress on the enclosure this weekend. Quite a lot yet to do but with luck I'm hoping to get it in primer and enamelled next weekend.
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Have set it up for flood coolant for the future. There's also box section at the rear to bolt the Z column to. If nothing else should be able to hold everything pretty rigid.
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Mill arrives next Saturday so hoping to make a start taking that apart soon. :smile:
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Re: Converting an AMAT25LV
I'm using the Oldham style couplings from CNC4YOU on my build. On the NEMA23 they clamp around the shaft with no other locating method (the NEMA34 motor has a woodruff key in the shaft, so I'll cut a corresponding slot in the coupler).
p
What's everyone's experience using these? Do they slip at all or is there not a problem. There is a flat on the NEMA23 motor shafts, so I can drill and tap the couplers and add a grub screw locking onto the flat if its worthwhile?
p
Appreciate any advise :smile:
Re: Converting an AMAT25LV