Planning a 4x4

[Oakley1975]

Hi all been a member of this forum for a while bot not overly active. I operate a Esab plasma cutter at work and wanted to learn more about how the cnc side of it works so I joined up here.

More recently I have been planning on building a cnc router table. I can cut anything I need out of plasma at work .. Having the privilage of full access to a large scale machine shop I an build everything to do with the table, gantry, rollers, rails ect.. myself with no problems. I just got a brand new Mastercraft Maximum 2hp router for christmas. All I need to aquire is the drives / software. I am wondering if the 4 axis package from hobbycnc with the 305 steppers will be sufficient. Not concerned about alot of speed just want it to be accurate.

Thinking on a chain drives for gantry and screw for z axis.

Would be needing control software too I see lots of Mach 3 ? software in use in here. Been reading these forums steady for the last two days as I am off work and now have a router !!

[journeyonline]

I built a 3x4 machine out of solid aluminum and some 8020, linear shafts, hobbycnc driver, 300+oz steppers with 36 volt power supply. It ran but was very slow and had to use a 4 to 1 gear ratio. My precision screws were 8 tpi and torque was not something I had much of. I would say use it for z axis, but as for the x and y try to use 450 oz motors or larger. I switched to 600+ oz steppers, 68 volt ps and geckos and now my machine runs smooth with plenty of power to spare.

[Oakley1975]

Thanks for the reply journeyonline... The more research I do it seems I will be needing more powerful motors. With the all steel construction and now possilbity of milling alumium, I will certainly need larger motors. Does not look like Hobbycnc goes any larger, will have to reserch more to see what else is out there for kits.

Just getting started on learning about the stepper motors and drivers so will have to research some more...

[journeyonline]

Get some gecko controls, they are affordable and have outstanding performance with support that is top notch. Email me direct if you like and I can talk more with you on this topic.

[fireballcnc]

I'd agree....Gecko's

[Oakley1975]

http://www.kelinginc.net/FourXCNCPackage3.html

Did a bit of research on this package... cant see why it would not work, using 2 motors for x.

Anyone use this equipment from this company?

[joecnc2006]

Look at my CNC 4x4 Hybrid, i use 1/2" 10 5 start and get very good speed for a DIY machine. I slave two motors and also connect them with a belt for backup in case i loose any steps the gantry will stay Sq.

Joe

[Oakley1975]

Originally Posted by joecnc2006 Look at my CNC 4x4 Hybrid, i use 1/2" 10 5 start and get very good speed for a DIY machine. I slave two motors and also connect them with a belt for backup in case i loose any steps the gantry will stay Sq. Joe

Thanks for replying Joe, so do you use the setup from this company?? I have read over most of your build threads and am sure I read what you use but there's a hollow spot between my ears that info gets lost in sometimes.. It seems that the kit would work well for a 4x4 fab from steel, after reviewing alot of other similar builds..

[joecnc2006]

On my proto type 4x4 I used the keling 425oz motors and the AMR drivers i built from a kit.

I do think the HobbyCNC 425/305 motors are better quality, just seem to run smoother.

Joe

[Oakley1975]

This is kindof what I had in mind for the table setup..... as far as the gantry and x drive... I like the idea of roller chain as far as ease and affordability. I'm thinking there would be minimal backlash having the chain mesh with the driven gear as much as possible, with considerable tension. .....

Just a quick mockup of what I was thinking ( got to love Paint for those quick "get the point across" drawings ) Of course there will be a sturdy frame underneath and all will be built out of mild steel.

I want ot hear all comments good or bad...

[Oakley1975]

Anyone used square stock for x rails and used rollers on 3 sides? I'm just considering the same design esab uses for their large gantry machines. Seems simple enough and dont need any special machining. Just use two sets of 3 bearings at a reasonable distance apart (16 - 18" maybe) on the end trucks.

Any thoughts?

[fireballcnc]

I haven't been paying attention, so I'm not sure if you've seen
this already, but it's pretty interesting....

http://www.cnczone.com/forums/showthread.php?t=48749

It looks like a Great useful design...

John