Hi

am a newby so can only offer an opinion, i am building a large machine like you, but a bit more ridged for stone. Like you, i first though get the motors, but, as i was told, WRONG WAY ROUND.

I would suggest



1. Design/Build your frame then gantry ( or pick one of the designs on here, most of them are good enough for what you want to do )

Think about rail sizes, and gantry weight in the design stage

2. Then ask on here about motors/servoes and cards. I was given some very good advice in relation to driver boards on my thread onb here. have a look atg them.

As a general ball park, i think your est of motors/driver and card should be between 500 and 700, depending on what you want to end up with.

The next part being quite important if you want to keep cost down and build easyer.

Do you actualy need a machine that big, As maybe a 4 foot by 4 foot, is cheeper, but a lot easyer to build. When you go bigger, you start running into engineering problems, all are get roundable, but none easy or cheep.

re the Chinees cards you link to

Ther eis an upgraded version of the driver chips, ( V3 ) that seems to get round the problem.

If you do get one of these NEVER GET ONE WITH THE STEPPER DRIVER ON BOARD, always seporate drivers. secondly. If you read up on here, you will realise that a lot of the power packs, sold with these kits, are to low power for heavy use of the motors,

So, for a cheaper 4ft by 4ft, thats not going to be cutting solid material all day, maybe, ther are worth a punt, but, the support on these chiness cards is none exsitant, i know that from experience. and the all in one cards ( with settper drivers on boards ) are a nightmare to use/setup and maintain.

Just my opinion and remember am a newby ( quite good at math and engineering though )