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deannos
10-03-2011, 10:07 AM
I'm building what is called the book machine and i'm now looking at the elctronic side of things. I saw this on ebay and wondered if this kit was any good, i will be cutting soft,hard woods.

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220747434212&ssPageName=STRK:MEWAX:IT


Thanks Dean

wiatroda
10-03-2011, 10:49 AM
Sounds good for me.
I'm using the same Breakout board and steppers in my CNC. Instead of PM542 drivers I have PM752, hence higher supply voltage.
With my setup I'm able to mill steel, and I would try the same with your set. Eventually in case of loosing steps or motor stalling I would decreased Feed rate.
But If you want to buy pieces separately I would recommend PM752 - http://www.slidesandballscrews.com/pm752-microstepping-driver-p-312.html?cPath=44_97
and some handsome 500W toroidal transformer (eg from Farnell- free delivery on orders above 20+VAT) + 25A rectifier bridge + big capacitor (voltage not smaller than DC after rectification).
for reference:
3833

Jonathan
10-03-2011, 01:35 PM
If you want to buy pieces separately I would recommend PM752 - http://www.slidesandballscrews.com/pm752-microstepping-driver-p-312.html?cPath=44_97
and some handsome 500W toroidal transformer (eg from Farnell- free delivery on orders above 20+VAT) + 25A rectifier bridge + big capacitor (voltage not smaller than DC after rectification).

I agree with getting PM752. I have also got them and the extra voltage will help with your motors torque/rpm.

I'm only using an 8A bridge rectifier, with 4 motors it's fine. Just get whatever's cheapest ...

The following capacitor from farnell is good value:
http://uk.farnell.com/epcos/b41231a9568m000/capacitor-snap-in-100v-5600uf/dp/1839296
(put two in parallel)

CLAYTON
25-03-2011, 06:44 AM
Dear wiatroda , why you may use PM752 instead of PM542 . I think both are good options I have not found any problem in using PM 542 .

Jonathan
26-03-2011, 01:15 AM
Dear wiatroda , why you may use PM752 instead of PM542 . I think both are good options I have not found any problem in using PM 542 .

PM752 is 75 volts, versus 50 volts for the PM542. Motor top speed is roughly proportional to voltage, so 75 volts will allow the motors to run significantly faster - hence get PM752 if you can afford them!

birchy
26-03-2011, 01:19 AM
I've bought the same kit recently for 205. The seller is Zapp Automation. I think I got lucky as it was an auction price starting at 180 and not too many bids. Most (all?) his stuff is now listed as buy it now.

wiatroda
26-03-2011, 09:17 AM
Dear wiatroda , why you may use PM752 instead of PM542 .
Jonathan is right. more voltage = more torque at higher speed.
Please google: stepper motor basics for some related articles or/and you can visit http://www.diycnc.co.uk/html/stepper_basics.html and other websites