Gina

I'm returning your thread to you Louise ?

I have no plans for an enclosed box - I do not plan to print ABS or other filament needing a heated chamber. Since you ask I'll cover the bed now. Or at least my initial thoughts. A frame made of 20mm x 20mm aluminium extrusion 500mm x 500mm outside will have an aluminium plate on top 500mm x 500mm x 2mm. On the underside of this will be a self-adhesive silicone heater pad rated at 1200W at 240v. On top of the aluminium plate a glass plate will form the printing surface. Here's a CAD model viewed from the underside.

The X and Y axes will be driven by the usual NEMA17 stepper motors with timing pulleys and belts in CoreXY configuration with one motor accounting for X+Y and the other X-Y. This simplifies the construction and uses two motors at the front and four pulleys at the back of the box with two pulleys on each Y carriage. The ends of the timing belts are attached to the X carriage. This is my initial Y carriage design. The X rail fits in the square slot (held with screw into the end) and ball bearing pulleys in the top and bottom slots.

As I recall Dave the Z carriages had rather closely spaced wheels - my Z carriages have the wheels spaced 150mm apart giving much better control. But the proof of the pudding...

Yes, I remember that you did that Dave and if I find the bed is not held level enough I may go for your solution. And yes, I shall be using a Duet control board. I was originally planning on using 3 Z drive rods but with belt drive. Decided it was too complicated and experiments with 4 rods on my Giant printer proved disastrous. Three motors means an expensive add-on to the Duet so if I can get away with two motors I can save money. EDIT :- For @tekkydaveChecked cost of Duex2 - £74-34. This seems an inordinate cost just to add two stepper drivers. Actually, really adding only one as the second extruder driver could be used for one of the Z drives. If only Duet had provided 6 drivers instead of 5 it would have been covered. Considering TMC2100 drivers cost about £8, spending £74 to obtain the same result does seem excessive. I wonder if there's an alternative. I can see the advantage of three Z motors. I wonder if one could connect three motor coils in series like we do for two.

Since the printer box will be on wheels, there will be space available underneath the base of the box. This has enabled me to mount the Z drive motors below the base and not only simplify the construction but add a bit to the available printing height (I might as well get as much as practical). As can be seen in the CAD model, the Z drive uses the standard threaded rods and a pair of stepper motors. The substantial Z carriages keep the bed level. The threaded rods are 8mm 1-start trapezoidal thread-form x 500mm.

The printing capacity of this printer would appear to be more than I originally intended. The increase in box size from 500mm to 610mm has resulted in a corresponding increase in the size of bed that will fit in and the available printing area. So the 300mm x 300mm bed of the Titan is replaced by a 500mm x 500mm bed size and printing area of 400mm x 400mm. By various means I think I can provide a printing height of approaching 400mm. I can't say if I shall actually get these printing dimensions until I have worked out the design of all the parts.

This printer will indeed be very heavy - I shall be fitting it with wheels (heavy-duty casters)! I guess I shall be building it in my living room but where it will end up eventually remains to be seen. Regarding ventilation, I shall not be printing ABS on it as that has been superseded by more user and environmentally friendly filament types.

I've started a Blog for my "GinaRep Concorde" 3D Printer

These photos show the "V" rail arrangement. The printer carriages use four wheels, two each side of the rail and separated along the rail to provide an accurately running carriage, constrained in all but the longitudinal dimension. The 2nd photo shows a "Mini" carriage (gantry plate). The carriages used in the 3D printer have the wheels much more widely spaced and the plates are 3D printed in thermoplastic (PETG). In the CAD model above, the wheels are represented by cylinders on the Z carriages and are 150mm apart to keep the bed as accurately level as possible over the Z range.

The box will be built from high quality hardwood plywood panels 18mm x 610mm x 610mm (2ft x 2ft). The Titan box was built from 500mm square acrylic panels with printed corners connecting the panels except for the base and back which were plywood, so I searched for ready cut pieces of plywood this size or larger and came up with the 2ft square sheets (a bit bigger than I really wanted but not by much). This CAD model gives an idea of the arrangement of some of the parts within the box. X and Y rails are aluminium extrusion "V" rail with the carriages running on them with matching ball bearing wheels. The Z axis also uses "V" rail vertical pieces with 3D printed Z carriages running on them and supporting the print bed. The Z carriages hold the bed level with any remaining deviation from truly level being compensated for in the firmware using Z probing immediately prior to printing. I'll say more about the "V" rail system later.

This 3D printer makes a bit of a departure from my others in that it is designed to give the best accuracy I can achieve rather than concentrating on speed or size, though I did want to print at least as big as my Titan printer (290mm x 290mm x 250mm). Like Titan it uses a box as the main frame but unlike Titan and my other printers does NOT use "pink string and ceiling wax". It uses tried and tested 3D printer designs rather than my usual "way out" ideas. I took advice from a friend who has spent a lot of time on developing high accuracy 3D printers.

YEP - RepRap is what it's about! I definitely use one printer to make parts for another - a lot of the printer output is for another printer or even the same printer. Once you have one 3D printer, others come along almost automatically (or at least they do with a Gina in the loop! ? ) My printers are based on RepRap hence my naming the range "GinaRep". Unfortunately, not all parts of a 3D printer can be 3D printed (yet). The frame of my "GinaRep Titan" printer is 3D printed plastic as is the frame of the bed, all the brackets and support structures though it does use aluminium extrusion for the running rails. This printer relies more on 3D printed parts than my other printers.

Yes, that's right! Hope they don't steal this one or I shall get annoyed and that is not a nice sight!!!

I think I shall soon be in a position to create a Blog and stop hogging Louise's thread ?

I think you've won again Dave (as I recall you named my "Titan" printer) - I really like the name "Concorde" though the printer is short and fat rather than long and thin like Concorde. Somehow the name Concorde seems to give a feeling or warmth and niceness. I like other aspects too like "high flying" and super-sonic - speed and grace. I'm hoping I can make this printer graceful and not an untidy mess!

This isn't the complete box as the sides would not be stiff enough. I plan to have solid timber rails across the top and bottom of the front.

PHEW... Lucky! Just one of the other three sheets was 610mm in one dimension as close as I could tell with a steel tape measure. I wasn't expecting to have to "mix and match" my ply sheets to make a box but I think it's turned out alright. The sides and back will have a "higgledy piggledy" top edge but it's for function rather than looks though I was hoping for good looks as well...

Measured the smallest sheet and it's 610mm wide with parallel edges - phew! Next is to measure up all the rest and find one that is exactly 610mm wide for the back...

Interesting thought - thanks Dave ? No cord in this printer though ? "Pink string and ceiling wax" almost describes my other printers ? Pink fishing line cord and melted plastic parts.

Well the plywood sheets are not all the same size ? Nor are the perfectly square So I shall need my large T square (used for drafting in my university days). One sheet is nearly 20mm smaller in one dimension than the rest. Not too worrying as this can be the base and fit inside the other sheets. BUT I need to check the base angles as I need the two sides to be exactly parallel as the Y rails will be attached to the side panel. If the base isn't square it will take a lot more work to get the printer built. Have to say, I'm disappointed as previously bought plywood has been perfectly cut. This CAD model shows the box made up from 4 sheets of 610mm x 610mm x 18mm and it can be seen that the base sticks out a bit at the front. In fact by the thickness of the sheets which is 18mm.

Re. name... Thesaurus hasn't really come up with anything new. The concept is very good and large - best results were "Deluxe" and "Grand". My original thought of "Deluxe" seems to fit and sound best. I think I want to give more an impression of "Posh" or excellence rather than large. I'm open to suggestions though - as occurred when naming my Titan.

Previously I have gone for a range of printers of varying sizes but it struck me that one size, well designed and solidly built printer should be capable of small, accurate prints as well as larger prints either talking longer to print or faster and less refined using a larger nozzle and thicker layers.

Not necessarily - depends on size of nozzle. This printer will have interchangeable hotends and possibly nozzle sizes up to 2mm though smaller sizes will probably get more use. But the main design principle is for accuracy more than speed. Hotends will go from the standard Volcano with nozzle sizes ranging from 0.4mm up to 1.2mm to home made heaterblocks with greater filament melting abilities and larger nozzles.

The industrial strength hardwood plywood for the box of the new printer has arrived and it's heavy. Sheets of 18mm x 610mm x 610mm (2ft x 2ft). I have yet to decide on a name, though one thought was "GinaRep Deluxe". The size works out as between my present "Titan" and "Giant" printers with an estimated printing volume approaching 400mm cube. (Titan 290mm x 290mm x 250mm - Giant 470mm x 490mm x 600mm).