My 4x8 project has started

[MetalHead6263]

Well , first I want to say a big thanks to all of those who have posted thier projects here , lots of great info ! I spent a year dropping in here reading , I was on the fence about it , then I got the fever to do it , so here I go !
First my welding fabricating skills are good , My electronics skills are low, so you guys are need to help me there ! I ve never even seen g code / mach / sheetcam software so thats gonna be a little scary .
After reading a few things being said by you guys stuck in my head .
Gantry should be stiff as hell , but light weight
For the gantry I choose a 40- 4080 extrusion from 80/20 on e bay it was 69 inches long [ to be cut to length later ] Bolted to this was a ivtaaqr rail from pbc linear its nice and wide and fits the 80/20 perfect for a super stiff gantry

[MetalHead6263]

The gantry with the z drive , less 2 motors came in at 44 pounds .

[MetalHead6263]

The gantry extrusion was cut 61 and 1/8 inches long

[MetalHead6263]

For the table , I used 2x2 14 ga tubing for the horizonal frame , 2x2 x 1/4 for the legs [ scrap i bought cheap steel is expensive !] and a 3x2 x 3/16 horizonal top tube for the rails to bolt to

[MetalHead6263]

On top of each leg I welded a 3x 4 -5/8 x 3/4 thick pad . I only welded two sides , I came in 3/4 inch on each corner and drilled 4ea. 3/8 hole . Weld on the sides opposite the bolt holes
I also welded some feet pads out of 1/4 to the bottom in case I decide to mount it on wheels

[MetalHead6263]

After the 2x2 tubing was all welded up it was time to bolt on the 3x2 tubing to the top of the leg pads . First I drilled all the way through the 3 x 2 tubing with a 3/8 bit . Then so the socket head of the bolt would go through the top only , I drilled a 1/2 hole only in the top .
I then bolted the pads to the tubing nice and flush , then clamping some spacer tubing to the horizontial frame for nice and square spacing , I tack welded the pads to the legs . I then loosened all the bolts so I could true / shim everthing nice and flat and square

[MetalHead6263]

Heres how I made it perfectly flat . I was surprised how bowed it was . Some guys suggested using a piano wire . I could just see all the wasted time and looks I would get trying to procure such and item in this rural area ! So I used a masonary string stretched with a 25lb weight . I clamped a 1/2 plated to each end , then used a 1/2 pipe to gague the bowing .

[MetalHead6263]

Her you can see some of the shiming . You will need to shim it perfectly level in both directions . This process took me about 3 hours some legs needed hardly nothing and some needed more

[MetalHead6263]

After the 3x2 top tubing was set perfect it was time to paint !

[MetalHead6263]

For the z drive and the gantry end plates , carriage plate and motor mounts I used No Sleep Studios product . I decided this would save me a tremendous amount of time with trial and error , I could of made them ,but I'm glad I found No Sleep Studio on this site ! The parts were well packaged and J. B. is a nice guy !

I also bought his floating touch and go plate which I attached a torch holder I made out of a 1 inch two piece colar from ace hardware . The colar is welded to a 1/2 plate piece which is drilled for two bolts .

I ran into clearance problems , so I made a spacer plate out of 1/2 aluminum to raise the z drive up to clear the table , seems real stiff hope it works !

More to come !

[A-abdel-glil]

i am making my new Mill CNC machine .... and i have some problems in finding the calculations as there is many formula for one thing... i want to know a calculations of stepper motor ... as how to calculat its torque, watt, ampere and voltage to select for it the driver then the interface board.. and thanks

[MetalHead6263]

For the y rails I used pbc linear ivtaas rail . I ordered it on a Monday and got it four days later ! Although the truck driver left them 7 miles from my shop at a hardware store , wizzes me off when thier too lazy to bring it to my shop .
Since the 3x2 top tubing rails were already trued , leveled and squared installation should be easy . A transfer punch would be real nice , but I didn't have one to mark all the mounting holes , so I marked all the holes with a pencil and a punch . I borrowed a friends magnetic drill press to drill 72 holes .
Since the tubing was 3/16 thich I used a 1/4 -28 thread tap for more threads . I started hand taping them , then I thought why not use a cordless drill ? Well in 8 minutes I tapped 21 holes then came number 22 Snap ! not good it broke off . After some patientce I got it all out , and continued to hand tap the rest . Tap magic is wonderful !
Here you can see the v rail hangs over 12 inches from the end of the head of the table so I can cut all the way through a 8 ft sheet .