Time for a new printer, Core XY, V Slot

So as the subject suggests, its time for a new printer!

If your looking for a printer made from flimsy printed parts and steel rods this page aint for you!
If your after something a little stronger with aluminium brackets that anyone with a pillar drill and hand tools can make, then this might the one for you!

Iv had a box prusa i3 for about 3 years now and my issue with it is the axis's are way to flimsy, mainly due to the use of 8mm steel rods for the linear motion. Also its not exactly house friendly as it pretty big, noisy, and the bed level gets thrown off eveytime it moved.
So I set about trying to find a new design that would fix these issues, and meet the list of requirement below,

Small foot print. This printer will hopefully live in the house, unlike my current printer which lives in the garage, so id like it to have a relatively small foot print.
Direct Linear motion Iv played with a delta bot before, and I found calibrating the non linear motion system and getting the bed level a bit of a nightmare. I know it can be done, but its not for me.
Quite Again been in the house id like it to be nice and quite.
20x20 V slot linear rails Iv got about 8m of the stuff loads laying around so its time to use it!
Mini V Wheels Again iv got a bag full in the garage so time to use them!
Portable Its likely the printer will like in our spare bedroom so it might need to be moved when we have guests
Mega rigid In my opinion rigidity of the frame and motion systems is crucial to achieving good print quality, and is often over look with most reprap printers. To achieve this I plan on making all structural parts from 5mm thick aluminium sheet, but only using hand tools and a pillar drill.
KISS Keep It Simple Stupid. Simple is best, why add complexity when its not needed. Simple means it easy to design, easy build, easy to modify ...

The first couple of points on that list essentially dictate a fix or Z only build plate, and the X and Y axis been on the extrude. (Im sure theres a name for this type of design, but you all know what i mean!)
So i set about looking for design that met these requirements, but nothing jumped out at me, so i decided to design my own. After all I find it much more fun designing and making my own designs, so why not!
I settled on Core XY style motion as i like the idea of stationary motors, and i can enclose the sides of the machine with aluminium or polycarbonate sheets to make it super rigid. Also all the electronics can be safely and neatly hidden away inside the frame.

So this is the design so far.

[postimg.org]
[postimg.org]
[postimg.org]
[postimg.org]

Couple of things worth point out.
Firstly this is far from the finished product, epically the Z platform and overall frame dimensions.
In the images the frame is currently 500 by 500mm, but once i am happy with the design i will reduce this down to fit a print area 200 x 200mm, im not sure about the height yet.
The X and Y carriage are all made from double sided aluminium plate to improve stiffness. The Z carriages are single sided. I chose single sided for the Z axis so i can easily enclose the back and sides, improving the overall frame stiffness, and the lateral load on the Z platform should be very small anyway so there is no need for double sided carriage hear anyway.

The current Z platform design uses 3 guides and 3 m5 threaded rods all driven from one stepper motor. I really don’t like the look the canter leaver beds, so three guides and screws was a minimum. I was tempted to change this to 4 but that would make enclosing the back a little more difficult. The choice of threaded rods over lead screws might surprise, but assuming the Z platform is sufficiently stiff in the lateral direction to prevent any Z wobble due to not perfectly strait screws, i see no reason why i should splash out on lead screws. Also if they are good enough for the E3D big box, they are good enough for me!

For the build platform I currently plan on using a sheet of ecocast aluminium from aluminium warehouse. The benefits of this are i can fix it directly to the z platform frame, and there should be no levelling problems like you get when you remove and replace a glass bed. I plan on simply sticking a standard 12V heated bed to the underside of the aluminium.

Any comments and questions are greatly appreciated, I’d really like to input of the reprap community!
I will keep updating this thread during the design and build. Im going to print all the parts and assemble the printer first before cutting any metal.

Edited 1 time(s). Last edit at 05/10/2016 03:00PM by Andy1989.

Personally, I think the delta design wins for print areas as small as 200x200mm because of its simplicity. Delta calibration can now be done automatically in less than a minute. You still need to build the printer accurately to get the best results.

Using cast aluminium tooling plate for the bed is a good choice. However, standard 12V PCB bed heaters are underpowered if you want to heat the bed to 100C for printing ABS, and the thermal mass of the Ecocast plate will further increase heating time. My advice is to design for 24V instead of 12V and use a 24V silicone heater attached to the underside of the bed plate, with a heating power density of around 4 to 5KW per square metre. For a 200mm square bed, that's between 160 and 200W, rather than the 100 to 120W that you get from typical PCB bed heaters. Using 24V power keeps the thickness of the bed heater cables reasonable, and keeps the current low enough for the electronics to drive the bed directly without needing to use an SSR.

I'm not sure what you have against using a glass plate to print on. I like the fact that I can remove the glass bed plate when a print finishes and stack it vertically for faster cooling so that I can remove the print (and start another print meanwhile if I want to). Otherwise you may have to wait a long time for your Ecocast plate to cool down enough for you to remove the print. Bed levelling should only be a problem if the glass is thin and isn't backed by a rigid bed plate such as your Ecocast.

These people [www.aliexpress.com] have a good range of silicone heaters, and they will custom-make one to your size/voltage/power specifications at a very reasonable price.

Edited 3 time(s). Last edit at 05/10/2016 03:31PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Deleted duplicate post

Edited 2 time(s). Last edit at 05/10/2016 03:30PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I was just think about 24v after I posted this. I will need a new power supply for this printer anyway so I I think 24v is defiantly the way to go.
Regarding glass I never though about glass ontop of cast aluminum! The reason I initially dismissed glass was just because on my prusa everytime I remove and replace it the level gets thrown off because it is only clipped to the flexible heated bed. I guess if it's clipped to a milled flat piece of aluminum that would remove that problem, and also allow faster part remove as you suggest!

Thanks for the suggestions!

If you have to swap out build plates, why not try clamping a piece of 1/8" or 3mm aluminum to the bed instead of glass? You can swap it as easily as glass, and since the cast plate underneath is flat, it will stay flat while printing. Aluminum has a greater coefficient of thermal expansion than glass, so when the plate cools after you remove it from the printer it will shrink more than glass and should release the print very easily. There's no danger of breakage and cuts with a piece of aluminum.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

That bed support arrangement looks so familiar (my SCOUTcorexy concept)
I like the simplicity of the rollers on the frame... they were criticized, demonized, then you see their adoption skyrocketing on kits and individual builds.

Edited 3 time(s). Last edit at 05/25/2016 11:08AM by realthor.

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RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff