Introduction

I'm new to printing and the forum. I've been lurking for about a week to get an idea of how these printers work. It is good to have a place where there is so much usefull info. I am building a printer of my own design, which I will start a build thread on as soon as it is far enough along to be intersting to the members of this forum. Nearly all of my parts are on order, and much of my raw material is here. This printer uses ramps 1.4 and the standard stepper motors in 17 and 23 sizes, and I have a hotend comong from Hotends.com to eliminate one headache. This will be a large format (2 cubic foot) machine with a heavy steel frame and a Z-axis build plate. I have worked out an adjustment scheme for the linear rods and plan on breaking just about every rule in the book to make this thing work. The goals are large build envelope, high resolution / precision and reasonable speed, as well as the addition of a multi color/material cold end. I do have a specific question: is it possible to use more than one bed heater, under glass, without having inconsistancy in heat around the border(s) of the heaters. Any input would be appreciated. MM

Go big or go home I guess. If this is your first build, you're going to run into all kinds of problems you didn't consider. Even building a tried and true design can be an exercise in frustration, so your starting off building a 2 cubic foot machine with multiple extruders and a (2 square foot!) heated bed is a very lofty goal indeed. Just think of the amount of power required to bring 2 square feet of glass to 110 degrees and the amount of power it will take to move that much mass. There are all kinds of variables and tradeoffs involved in building one of these which is why I would recommend starting with a proven design. Then again, I don't know how much experience you have building things like this.

Well, I do have a bit of experience machining and welding, and I have a lot of machine knowelege. First off power, I will use 2 30 amp PSUs, one for bed heat, one for everything else. As to moving the bed, that was my first concern. So the very lightweight bed will be the Z axis, with pair of 23 size motors turning trap lead screws with top bearings and linear bearings on four 12 mm columns. My frame will be a one piece welded steel frame, which is nearly all cut as of this evening, and is built to high angular and diminsional tolorance. All linear rods have adjustments to allow for precise alignment. There are fans on each motor, the hot end, and additional fans for each PSU and the ramps setup, vented from outside of the main build area. the unit will be enclosed and have heat to use with (particularly) higher density, and larger sized ABS models, and local cooling at the just laid area. This should assure that models don't tend to deform. Keep in mind this heater won't be all that hot, but warmer than room temp. I am working on a design for what will utimately be the multi feeder, for now the cool end will be direct drive. I am working on a design that will allow for a number of filiments to be used but will keep all the size, weight and resistance off the carriage, but for now I do want to get the whole thing working well with one color. If this is successful, then this IS the small machine; my drawing board is a forward looking space but for now this is the project at hand. Once I have the last metal bits cut out, I will post some pics.