[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 !:cheers:

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 :boxing: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 .

[MetalHead6263]

I snugged the bolts down in a few locations and checked the width of the vee rails as well as level , no shimming or adjustments were needed .Here you can see one way I checked the squareness of the gantry .
I clamped some spacer tubing to the end of the table and man I was off ! What the heck is wrong , I added spacer washers to vee rollers and end of the gantry for three hours and it worked . But I looked at it and was not happy since this threw off the spacing of the gantry end plates . I took the end plates off and saw the squareness of the cuts to the ends of the gantry extrusion were very slightly out of square , no way was this little bit making me so bad out of square or so I thought .
After putting on my reading glasses [ this helps tremendously !] I hand filed it perfectly square in two directions . Bollted the end plates on , and man it was perfect !

[MetalHead6263]

Heres a break down of the time so far actually building the machine . This does not include all the parts procuring .

Fabrication of table 2 days , includes truing top 3x2 tubing
Priming 1 hour painting 1 hour plus dry times
Mounting y vee rails and gantry installation 1 day
Making adapter plate for z drive and misc other fiddling 1 day
So I have about 4 days actual build time to this point :cheers:

Next is ordering in the gear rack from Moore Gear

[cobretti]

Table looks great so far metalhead...I can second J.B's kit being a great time saver and it was definitely money well spent!

I can't believe you got your rails in 4 days, mine took just under 7 weeks from PBC but they are also worth it and I would probably buy them again.

Look forward to see the table in action.

[MetalHead6263]

Thanks Corbetti , I got the gear racks today from Moore Gear . Man they don't take any chances with flimsey boxes , I have enough wood from the crate to build some shelves for the shop ! Lots of stickers telling the shippers not to f it up ! Also ordered a dragon cut , mach 3 and sheet cam from c andcnc .

[NIC 77]

MetalHead,

I'm about to start a 4 x 8 cutting area shopdroids build myself. It's going to be for Routing and Plasma. The one weakness, in my opinion, of using the shopdroids design for larger builds is the lack of stiffness. An aluminum T-slot extrusion 2 inches by 2 inches could have alot of flex over a 4 foot span.

I'm not sure if this is an issue for plasma as I'm guessing the forces at the cutter are negligible compared to those generated by routing.

I've spent all my free time this past week reading and designing, and thinking about ways to stiffen up the IVT rails. For the past 4 days I've thought that I would be ready to place an order for the IVT that day, but I kept having one more thing to figure out before I would be ready to order my rails cut to the exact length I'd want.

I have already ordered my Router kit parts from Shop Droids and that should be arriving in a day or two.

I've decided to go with a welded steel support frame for the IVT rails instead instead of using 80/20.

About 5 minutes before reading this thread I thought I was ready to send in my e-mail to order for the IVT, but now I need to know something first.

My question for you is this:

The normal Pacific Bearing extrusion for the shopdroids design is the IVTAAG rail that has an "R" dimension of 64.95 mm.

The IVTAAQ rail that you are using for your gantry has an "R" dimension of 104.95 mm.

How did you get the shodroids carriage to work with the extra 4 cm rail width? Was it a custom kit? Did you move where the holes go? From the one pic I can see of both sides of the gantry carriage, it looks like it fits perfectly.

If you could please take a minute to explain how you did this I would really appreciate it. If I can make the IVTAAQ rail work for myself as well, then that's what I'm going to do and I really need to get these rails ordered.

Thanks in advance.

[MetalHead6263]

Yes , I figured out in my design stage that a wider stiffer gantry was needed for my table , yet super light weight . You are correct J . B. made a custom carriage plate and gantry end plates for my design . If you talk to him tell him this and he will know what to make you . There is no slop in the carriage , you us 2 concentric bearing bushings on the bottom of the carriage and 2 ecentric on the top .

[NIC 77]

MetalHead,

First off, thanks for the prompt reply. I've been thinking of little else since I wrote my last post. I think I'm going to order my rails tomorrow. Unfortunately, I already ordered the standard Carriage size kit. I did not know this option was available when I ordered. It should be arriving tomorrow or the next day I figure.

Right now what I'm thinking is I'm going to order the IVTAAQ rails for the gantry and the IVTAAH rails for the other two sides.

This means I'll need a new Gantry carriage. I'm either going to make one from aluminum (should be easy, I just need to drill 4 holes) and bolt on the shop droids motor mounts to it, or e-mail shopdroids and see if he will make me up just the one piece I need. What I need to do should become apparent once I get some parts in my hands.

Also, I won't be using any T-Slot, I plan to bolt a 3x3 piece of steel square extrusion onto the IVTAAQ rail and weld that directly to the other two carriages.

Obviously, the gear rack will be mounted half an inch higher than for the original shopdroids design. I figure I can do this with a half inch spacer made from aluminum. I don't know from your posts if you have figured this all out for your design, but I'm guessing you will need to do the same.

What do you think of this idea? I value your input. Thanks again.

[MetalHead6263]

Personally , I would not weld the endplates on , that has to be perfectly square , true , and level . I cut mine crooked , and was out of square bad , so I hand filed the ends perfectly square .