Build Limits for Stainless and misc

Well, I have been lurking around here a short time now, trying to contain the impulsive excitedness of 3DP, and I find myself really really really discovering I need this project and I cannot live without it; maybe. Haha. Anyways, I am looking at starting to print pieces here once my current backlog of prints are done.
The goals:
***I would like to make two builds of the machine. One I would like to have become a large dedicated printer that would solely focus on doing large prints. The reasoning is that my current printer has a print area of 9" x 6" x 6" and some of my prints can reach sizes exceeding 48" long and 12" tall. Normally I just split my models and assemble in pieces with alignment dowels. However, this increases post processing time significantly. If I could instead build a MPCNC with say a print area of 48" x 24" x 12", things could get a lot simpler. I am wanting to see if this is easily achievable for ABS and PLA printing? I would also be using 1" OD stainless tubing as suggested with the 0.049" wall or step up to 0.065" walls with mid supports every 18-20". Also would consider building the Printer to be taller rather than wide. Have it print straight up with a small X Y foot print of maybe 12" x 12"? and Z like a stupidly crazy 48"

***The second machine I would have dedicated to milling and routing for 3/4" MDF as well as Urethane Foam for making mold plugs. Still going with stainless and mid supports, would a 48" x 48" x say 6" Z be a pretty workable area for the machine?

***A few leftover questions for the masses

  1. Any need to upgrade the steppers?
  2. Spindle vs router/dremel 660w?
  3. Heated bed design for such a large print area?
  4. Heck…a heated enclosure to keep the part from cooling too much before the extruder makes its trip back (assuming a large print that uses the bed fully)
  5. Haven’t really used the software side of things in several years, shouldn’t have issues if I were to program CNC toolpaths in MasterCam?
  6. How well does the MPCNC handle flowlines and 3D curvatures when tooling?
  7. Upgrades for 1/2" shank tools?
  8. If rigidity is an issue, has anyone considered temporarily capping the tubing and filling with 2 part expanding urethane foam (not great stuff). Remove the caps afterwards and have a dense foam filled tube without having added much weight?

I apologize if this information has been covered. I scoured the forums a good bit until the dates got to be over 8 months old and I figured that with the developer being so good about updating his design, things that were once the Iron Law and now nixed.

Run through the FAQ and see if that answers some of those questions.

And this one

Thanks! I had browsed through the faqs and a large amount of forum material as well as the process of building the MPCNC. Lots of good info, was just hoping to see some input from the guys with similar builds/ideas that are up to date with most recent parts and steel tubing. I guess I will just have to build and see what happens! If things don’t work out, that’s what engineering and modding is for :smiley: