[InventIt]

Just wanted to say THANK YOU to CNC Zone and the great people on here. I know this project would never have happened without the awesome resources here.

[ger21]

I think those are about $3-5000 new. Expect to pay about half if you have to have it rebuilt at some point. At work we have 9HP spindles, so I can't really say how much power the 3HP will have, but probably quite a bit more than the PC you're using. And it should last a LOT longer. They're very quiet, too. Sorry I can't be more help.

[signIT]

Hi InventIt,

Just a question about your end bearing for the z-axis how do you manage the bearing for minimum play and what type of screw and nut are used?

I will start a cnc project with THK rails X and Y 640mm x 640mm the best reference I ever seen is your project very well done.

Greetings

Leffe

[InventIt]

Thanks SignIT,
The Z axis screw is supported at the bottom by a bearing block that bolts to the z axis plate. I turned the acme screw down to 3/8 and threaded it with 3/8" fine thread then used a friction nut to get slight preload on the bearings. The bearing block is just a 3/4" thick alum plate with a pocket on eack side for a 3/8" roller bearing. The top of the acme screw is not supported, it just connects to the stepper via. a helical spring coupler.

[Txfatboy]

Great Machine. I would like to see a final picture. Also what software are you using? :banana:

[calaber40]

hi guys im new to this cnc stuff and a quik learner when it comes to building things. im well into my build and am at the point of installing my 2 screws under the table for my gantry. what worries me now is what i have read in regards to 2 stepper motors running each screw and having them go out of sink ,so to speak, and all hell brake loose. i was first going to go the one stepper motor in the middle with 2 screws and a timing belt .motion tech . the supplier of my rails and electronics advised that i would get to much backlash, this way.is this true ,or does he want to make more money off of me.lol.my machine is about 48''x60'' so the belt will be spanning about 20 to 24'' across. i am looking to cut foam , mdf . and useing a trim router . if anyone have any imput on this area of a biuld , it would be very appreciated.you can see my cnc in the photo gallery.[ these are the pros and cons i ponder]

[CarveOne]

hi guys im new to this cnc stuff and a quik learner when it comes to building things. im well into my build and am at the point of installing my 2 screws under the table for my gantry. what worries me now is what i have read in regards to 2 stepper motors running each screw and having them go out of sink ,so to speak, and all hell brake loose. i was first going to go the one stepper motor in the middle with 2 screws and a timing belt .motion tech . the supplier of my rails and electronics advised that i would get to much backlash, this way.is this true ,or does he want to make more money off of me.lol.my machine is about 48''x60'' so the belt will be spanning about 20 to 24'' across. i am looking to cut foam , mdf . and useing a trim router . if anyone have any imput on this area of a biuld , it would be very appreciated.you can see my cnc in the photo gallery.[ these are the pros and cons i ponder]

I have similar concerns for my second build which will use dual steppers on the x axis. The Solsylva belt drive on my first build can slip if one lead screw binds and the gantry gets out of square. The dual stepper direct drive that I will use on my next build can have more serious problems if one side binds up while jogging at much faster speeds than I have available now. Just have to make sure everything stays in alignment and running freely.

CarveOne

[calaber40]

hi inventit. i like the way you set up your pully system . is there a reason you went with three belts instead of one with a tensioner .and does the size of the pullies make for more or less backlash. eg. bigger pully more contact on the belt ,so more teeth can bite,that sort of thing.if thats the case ,does it effect the tork on the stepper motor if there bigger.and providing there all the same size.is it possible to get a more illistrated pic of the centre pully setup .really torn up at this point of my build . i dont want to spend 350.00 bones for another stepper , driver , and power supply ,only to find out it will work just as well with a belt system.plus i dont want to ever exsperience my cnc machine rip itself apart if one motor goes Awall lol.ps great build must have read it a dosen times thx .gino.

[calaber40]

do you think adding a extra motor driver and power supply is cheaper than a pully set .if its less than 350.00 i think all go with the pully set not just for cost but also if something goes wrong it wont tear my cnc all to hell.and exercisums are not cheap either.as a new be at this they say sh??t happins,and it will.any good place to pick up some pullies and belts at a good price?.