[EZELab]

Hello,

I was going to buy a small machine, But I decided to gain more experience by building my first machine.
I have little experience with building process . All my knowledge I have is from reading & reading.

My machine work area should About 1500MM x 1000MM, I'll cut Wood, Plastic & Alum.

I'll use Plywood for body. With Ball screw & Supported rails.

I'll order the ball screws & rails from linearmotionbearings, The most recommended seller on CNC Zone.
Motors & Drivers from automationtechnologiesinc

For the driver, I'll use Gecko G540.

For motors, I'll dual drive the Y axis from both sides.
But what is better for motors, a NEMA23 425oz/in 2.8A Or NEMA23 381oz/in 3.5A, which one will better for my build, A higher current of higher oz.

And about motion system. which should be larger, The ball screw or the rails. Chai have some packages that have ball screw larger than rails & the opposite. Hi didn't specify the end machine dimensions.
I'll use RM2005 for X & Y with 20mm rails & RM1605 for Z with 16mm rails.
So, If I ordered a 1650 mm length ball screw with end machined, What is the rail length should be.
I got a offer from him as following :

2 SBR20mm x 1650mm length rail with 4 bearing blocks
2 SBR20mm x 1150mm length rail with 4 bearing blocks
2 SBR16mm x 750mm length rail with 4 bearing blocks
1 RM2005 x 1550mm ball screws end machined
2 RM2005 x 1000mm ball screw end machined
1 RM1605 x 650mm ball screw end machined
4sets BK/BF(3sets BK/BF15+1set BK/BF12)

Is this normal that rails longer than ball screw ?

Thank you all

[ger21]

I would recommend 380oz motors, and 1610 and 2010 ballscrews. 5mm pitch will give much slower speeds.

The length of the rails and screws are entirely related to your design. If you buy the ballscrews and rails first, you'll need to design around the specific sizes.
If you design first, then you'll want screws and rails that work for your design.

[EZELab]

I choose 5mm pitch for a higher accuracy, I don't have problem with speed, I just need accurate machine as I can.

About the length, I'll buy parts first than I'll design the machine, But should I order them as the offer above, Or edit to make them equal or order longer ball screw than rails ?

BTW. I am planning to add extra nut for each ball screw in future, to Get ZERO Backlash.

Thank you

[EZELab]

Also, I have 2 Mean Well power supplies available, on is [email protected] and a [email protected]. If I used a 380 oz/inch, They they will be 3.5 * 4 = 14A.. I think I should use the 36v. Right ?

[misterbusiness]

plywood-DO NOT WANT.
if you're going to spend the money on nice rails and drive systems,use steel or alum.I have a simple frame,all the rails I have are adjustable but sturdy,and I used a lot of UHMW for the plates and drive blocks.Ive seen some success with plywood,but way more with MDF.
But like I was saying,if you're already spending some dough,dont just slap together a body and frame,man.thats the only stuff thats hard to replace-electronics and mechanics are all almost plug and play long as you order the right sizes.get someone to cut you something out or aluminum or a moderate steel at least.