My Recently Finished CNC Plasma Table

[Jcar]

Gentlemen,

I've had several PM requests for drawings of my water table. I'm attaching a PDF file, which contains scans of the 3 layout sheets that I gave to my local steel supplier. I had them shear and bend the parts, while I did all of the welding. Cost for 2 sheets of 5' X 10' 10ga and labor was around $350 ($140 per sheet and $70 labor).

[Jcar]

Here's a DXF file of the slat hangers for the water table.

[totalfab06]

How could I get the original file from Thermal dynamics?

[Jcar]

Totalfab06,

Just Private Message me your email address, and I'll send you a copy.

Jody,

[Jcar]

I also want to add that I welded X braces to the top side of part 2 and the under side of part 3 in the above watertable.pdf file. The braces on part 2 are located within the air chamber area just like the braces above them on part 3. They were made from .125" X 2" flat stock welded on edge.

[Dizzy_G]

Wow Jcar,
I have to say reading this thread of your build has saved me so many head aches. I'm in the process of contemplating a Plasma table build and you have hit the nail on the head with this design. I'm very impressed, the build quality is top class.
Can i also get a copy of the Thermal dynamics file. I will PM my address.
Once again well done.
Best regards,
D_G

[Jcar]

Dizzy G,

Thanks for the kind words. If you need any help with your build, feel free to ask.

[Dizzy_G]

Jcar, what is the overall footprint of your table if you don't mind be asking, can you leave out the two support legs so i can get an idea.
Thanks,
D_G

Thanks Anvil, i had just come back to edit my post and ask the exact same question. Still hungover from the weekend so i forogt all about asking.

[anvil]

Beautiful machine Jcar. I've read your original post about 5 times and I just caught that you have 2 steppers running one axis. How does that work? Are the steppers run in parallel off one drive or did you split the step and direction signal to two different gecko drives?

[Torchhead]

Anvil: Sorry to jump in on a question to Dizzy_G but you can't run two steppers off one drive....does really ugly stuff to any anti-resonance circuit and causes interaction between two mortors youdon't wnat. You can (hardware) slave two drives together by running the same set of step & dir signals to them provided the interface (from the PC) has enough current capability. MACH software also allows you to software slave any two axis and that approach has some advantages (over hardware slaving). You can setup separate home swtichs that will automatically "square" the axis everytime you home. Dual drive systems are very common and offer a cost effective way to both double the drive torque and keep the gantry from racking. You can do it mechanically with a drive shaft but it adds to the mechanical complexity.

[Dizzy_G]

Hi Torchhead,
I had considered the mechanical approach but would be a slight problem if i was to follow Jcar's table design as the table is so deep.
So I could use two smaller motors for the x-axis along with two drives, instead of one large motor which is driving one side and may cause racking. Also would it be necessary to use a breakout board to add the second motor? Are the two motor drives effectively in parallel off the one signal line or is it two separate signal lines and the software "matches" the step pulses etc. and signals?
I can see how two motors on one drive would cause problems alright with step pulses being all over the shop, but I'm intrigued with the idea of the software being able to manage everything.
Which would be the better approach hardware slaving or software slaving? I assume software wins out with the dual homing option.
Thanks
D_G

[Jcar]

Dizzy G,

The inside dimensions for my water table are 60" X 60". The top flange is 1 1/2" wide so the outside dimensions are 63" X 63".


Anvil,

Thanks. My system is controlled by 4 Gecko 201's. X axis, Y axis, Z axis, and B axis. One side of the gantry is controlled by the Y axis motor and it's gecko drive, while the other side is controlled by the B axis motor and it's Gecko drive. The B axis is "slaved" to the Y axis in Mach3's configuration settings. When Mach3 sends signals to the Y axis motor and drive, it also sends the same signals to the B axis motor and drive.