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Colin Barron
15-10-2016, 03:03 AM
I Emailed GSK in China for the cost of their GSK980MDc, 750w servo for x and y and 400w for the Z.
They replied:
Dear Colin,

Thank you for your reply, please find in the attachment a kind of milling machine which regularly retrofitted with our CNC system, I am not sure if it is similar to your machine, the machine worktable size is about 1270*254, and travel is about 720*380*125. For this kind of machine, axis motor is driven by belt, we mostly use 6Nm motor for X/Y axis, and 4Nm for Z axis, in this machine Z axis motor is only driven the spindle sleeve up and down, the motor rating is smaller and without brake, if your machine Z axis is not like this, may will need motor with brake also.



Shall I take reference of this motor rating for you or give as you asked as 750w motor? For your information, our axis motor of less then 1kW is same price as 1kW(4Nm, 2500rpm rated, 3000rpm max) motor.




Regarding the CNC system solution, you can refer to the following CNC system package:



GSK980MDc CNC system

including:

GSK980MDc CNC controller 1set (8.4 inch Color screen, USB interface, 41 input and 36 output for user define with built-in PLC)

6Nm servo motor with drivers without brake 2sets (2500rpm rated, 3000rpm max. 5000ppr incremental encoder, 130SJT-M060D(A2))

6Nm servo motor with drivers with brake 1set (2500rpm rated, 3000rpm max. 5000ppr incremental encoder, 175SJT-MZ060D(A2))

Handwheel(MPG) 1set (On controller panel)

Cables (5m) and accessories



The price for the package is USD3600 FOB Guangzhou, China.




The above package with 4Nm servo motor and drivers (2500rpm rated, 3000rpm max. 5000ppr incremental encoder, 130SJT-M040D(A2)) is USD90 less in price.
The above package with 750w servo motor and drivers is USD90 less in price, same as 4Nm.


The price of GSK980MDc controller alone is USD1800 FOB Guangzhou, China.



I have read several posts where they have said 750w for x and y was the way to go whereas gsk are suggesting 1.5 Kw is best. Any comments would be gratefully received.
Thanks
Colin

m_c
15-10-2016, 12:44 PM
My interpretation of their reply is that they do a standard package with controller and three 6Nm/2500RPM servos for $3600.
If you want smaller motors, reduce the price by $90.
.
I probably wouldn't want to go any bigger then 1kw on a Bridgeport.

Boyan Silyavski
15-10-2016, 02:48 PM
You are a rich person. For that money you will buy 3 motors and drives from BST Automation (https://www.aliexpress.com/store/group/Servo-Motor-Driver/314742_256838494.html?spm=2114.8147860.0.0.wVLNHB) (800euro), plus Servo motor for the spindle (450euro) so you could rigid tap, then buy (700euro) controller copy from Aliexpress -Newkye , pay 250 euros for DHl and even pay your duty tax and still half from what they want :triumphant:

komatias
15-10-2016, 03:12 PM
You are a rich person. For that money you will buy 3 motors and drives from BST Automation (https://www.aliexpress.com/store/group/Servo-Motor-Driver/314742_256838494.html?spm=2114.8147860.0.0.wVLNHB) (800euro), plus Servo motor for the spindle (450euro) so you could rigid tap, then buy (700euro) controller copy from Aliexpress -Newkye , pay 250 euros for DHl and even pay your duty tax and still half from what they want :triumphant:

What spindle motor is that Boyan?

Colin Barron
15-10-2016, 04:41 PM
You are a rich person. For that money you will buy 3 motors and drives from BST Automation (https://www.aliexpress.com/store/group/Servo-Motor-Driver/314742_256838494.html?spm=2114.8147860.0.0.wVLNHB) (800euro), plus Servo motor for the spindle (450euro) so you could rigid tap, then buy (700euro) controller copy from Aliexpress -Newkye , pay 250 euros for DHl and even pay your duty tax and still half from what they want :triumphant:

I was really looking for the sizing information. They are suggesting that a motor sizes of 1.5kw are optimum wheras most on this website suggest 750w. Are BST good quality, i noticed the panasonics for about 500. Is the 700 euro a copy of the gsk?
Thanks for the reply.

komatias
15-10-2016, 05:02 PM
Collin,

I am pretty sure the 750W is enough since you are going to gear it. The 1.5kW however for $90 is not a bad deal. I know that GSK controllers and Servos work well together and you will get decent support for them.

Just be warned that the 980MDc and any 980 for that matter requires a bit of ladder tweaking and macro writing if you are planning to use repeatable Z tooling like the stuff I sell.

Boyan Silyavski
15-10-2016, 06:46 PM
What spindle motor is that Boyan?

They sell 2.3kw servo motor for that money if sb feels like fiddling. Though i have read that VFD and encoder also could do the trick. I just sait its cause i saw the big motor for that money. Anyone should check if this is specifically possible due to shaft sizes, length, etc. Anyway, for me anything is possible if i put my mind on it. There is always a way

komatias
15-10-2016, 08:26 PM
They sell 2.3kw servo motor for that money if sb feels like fiddling. Though i have read that VFD and encoder also could do the trick. I just sait its cause i saw the big motor for that money. Anyone should check if this is specifically possible due to shaft sizes, length, etc. Anyway, for me anything is possible if i put my mind on it. There is always a way

Commutation servos usually go to 3K rpm. Spindles should go to 6K preferably. Have you per chance found a VFD with encoder inputs or are looking to feed the signal back to the controller? The latter is potentially possible in Mach too, Novakon do that I think.