Servo stepper debate

[Ubatoid]

Ok Ive got the bulk of the table drawn up (10 x 5) and I now need to start on the gantry and start thinking about speed and reductions. I had made up my mind to go for servo drives to make sure I have the power and speed to cut at 500 ipm max and have the torque to route aswell as plasma cut. Ive read Toms servo/ stepper pro con list but I am now doubting myself and thinking big steppers rather than servos that I may have to gear down some 10:1

My main concerns are haveing a quick enough z for cutting corrugated roofing and quick enough / accurate enough XY for cutting 22swg mild but having the power to route MDF.

I will welcome any input.

[Feckless]

Yeah it's a tough one, there is a lot more setup in servos, I am planning a change from steppers (270oz/in) to servos at around 400W but the bigest hurdle I'm facing is to eliminate the HF noise as I plan to move up to HD. Things just go silly if I go above 3800mm/min (150IPM). I like the flash cut hardware and software I currently use and I'm thinking I can keep the software and signal generator, just replace the stepper driver and power supply and the motors and cableing, put in home and limit switches. The AVHC I use will also need to change I think. I'd prefer if the software could incorporate the torch height, I know Mach3 does but the other options in flashcut are nice.
I am desigining a new 5x10 table, up from 8x4, But I have the advantage of having a plasma cnc to make any bits I need.
What system are you thinking of going with besides Candcnc drive systems.
I hope I'm right on the facts, I only started looking at upgrades about a month ago.

[Feckless]

I meant to say, have a look at Millmans thread on his build, he made a sweet sweet machine, he used steppers if I recall but a bleady nice build.
Regds
Gordon

[Ubatoid]

I plan to use v rail down one side of the x with cold rolled flat with plain bearings the other side and double v on the y. I've spent another day thinking about it about it and have pretty much convinced myself to go the servo route, we have some nice alum box section on the tube rack for the gantry.
I've followed Millmans build closely and took his take on the water table and modified it slightly to suit available materials. I will try and post up the g/a on the next few days. I will be most interested to hear how you get on with your build.

[Feckless]

Yeah, I'll put up a post when I start the build, Both sides under slung ie, rack and rail outside and lower down, steel folded crossmember, Hardened rails x axis and double 25mm cassette Y axis. I plan to have plasma (HD), Oxy fuel and engraver on the rail hence steel.
I have worked with the crs and cam bearings for the past few years, they're fine but if you can, go with rails. I am forever cleaning the crs top plate.

[lgalla]

Ubatoid,If you use rack&pinion,steppers need gear reduction as do servos as R&P is fast.
DMM tech has a servo kit of 900Watts with top speed of 1000RPM.3to1 reduction would be good.These servos are a good replacement for steppers.
Motion Control Products - DMM Technology
Larry

[Ubatoid]

Thanks Larry, that's a nice tip. I have to admit I have been rather blinkered with my choice of suppliers and only considered Cand. Looks like DMM do some nice kit. Thanks again.