New Build Advice for large bed printer

I find myself in a dilemma where I have build a jukebox casing I made from 20mm ply with my MPCNC and now need some finer detail beadings around the Opal Perspex which I am not able to find as a ready made off the shelf item. I have set the front forward by 100mm and the perspex is cut to fit the curve at the top. This leaves me with an ugly edge where the bendy ply sits on top of the ply form. I need a trim to follow the radius of the curve. 15mm x 15mm deep approx 5mm thick

I made a prototype from ply but want something a bit more classy.

Why is it that when ever I need to print something, my bed size is always too small and I end up having to break the item up into pieces? None of my 3d printers can handle anything over 300mm. For this, breaking it up into pieces is not an option, I need it to look right. My OCD

My gut is leading me to consider 3d printing the beadings as cnc tends to break them apart being so fine.

Trouble is that I would need a bed size of say 700mm long. The width I don’t think is an issue as the curve is such that it can fit inside 200mm width.

As this is a fairly small demand project I dont want to throw too much money at it so i was considering building a modified version of the MP3DP V1/2 with an extended bed.

Is that my best solution or should I consider a smaller version of the MPCNC but with a print head?

I have loads of projects that have been build and disassembled so I have lots of bits to hand including extruders steppers etc. Which would be the most cost effective method to achieve this goal?

I am considering the MP3DP version 1 which is a nice simple design that would lend itself to an extended bed. I did build a 400x400 multi color Corexy which I considered to use a similar design but its a lot more work than I was hoping for for a small project.

I quite like the idea of a printer along the lines of this one I saw on youtube

Anyone got any ideas? I do have a really old Wanhao i3 V2 that I could perhaps try modifying but from my research it does not seem to be very highly regarded as a model for modification. I know Jeffeb3 had one of the early versions and did not think it was a great starting point. I would like to include auto bed levelling obviously with such a long bed.

Has anyone any experience in building something of this nature. I dont want to go with a huge 700x700 as that is just too cumbersome especially when it comes to heated beds. I can get 200x 300 silicon beds at a reasonable price so was considering using those in tandem.

Any ideas appreciated but my gut is to go with something similar to the MP3dp v1/2.

I wouldn’t use a 3d printer for this.

Cut a form out of plywood. Pick a hardwood you like the looks of. Steam the hardwood and bend it to the radius using the form. Depending on the wood, you might have to make the radius tighter as it will spring back after it cools/dries. Use a regular router table to put a decorative edge on it (round over, chamfer, etc)



Make a form/mold in multiple parts, and use resin to make a single fitted part.


Make a CNC milled part larger than your cnc bed by tiling the job. Use a couple of registration holes in the material, then cut half, flip the material over and cut the other half.

A very large 3D printer means more possibility for things to go wrong, and also takes a long time to print. Coordinating a triple length heated bed is a lot of work, and keeping the motion smooth on that long axis is difficult.

My dad still uses it. It is good. But I added enough parts to mostly replace it, and the usable bed area is smaller than a mini now.

If you want to print it, what about a belt printer? A long bed like that will not have good Z height if it is only supported at the ends. The middle will sag, which is where the print is happening. If you printed on a big raft, it might work. But it would be a shame to make a printer that large and have it fail.

Another option is to just order it from a printer.

I do think making it from wood is easier. I don’t know if I would bother bending it. It could be cut from a larger piece. It would waste some. But it could be cut on the cnc. I bet the original was bent.

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Thank you all for your input.

Bending wont work as it needs to be an ‘L’ shape. I tried the cnc route to route out the curve and the ‘L’ but then I needed to add a chamfer on the other side and routing something that fine did not sit well with me. I had to keep checking I had all my fingers. A proper router table I am sure would help, but that’s not something in my tool collection.

I did consider making a mold but by the time I had broken my design down small enough to fit my printer bed I decided that was going to be a messy lush.

The original in my photo I did on the MPCNC out of ply and then routed the bevel as the square edge did not look pleasing. It took several goes as the ply kept having bits break out of it. A solid wood would certainly be a better bet, but Where I stay, is not very plentiful. I also worry that with a small piece like that it will keep breaking on the grain.

I looked at belt printers Jeffeb3, I see a few mod kits available for some of the creality printers. I have just ordered one of the Creality Ender 3 Neo machines which are cheap as chips right now, I guess as the V2 is out and pushing the prices down. Has everything you could ask for, auto bed levelling etc. I am going to set it up for a friend who is just starting out in 3d Printing and the easier it is for her to get to grips with it, the more likely she will stay invested in it as a hobby. She was going to buy my Wanhao but I decided it would frustrate her more than she would enjoy it.

I looked at rubber profiles as an option but that did not work out either as I couldn’t find the right profile nor did it look pleasing.

I think I have convinced myself to mess around with the old Wanhao i3 as a project anyway as its just collecting dust and start by trying to get auto bed levelling to work with the standard Melzi board. Just because I have time, curiosity and most people say it cant be done. If I brick it, then I can always stick one of my Ramps boards in or break it up for parts.

I guess I am resigned to being stuck with a wood beading for the jukebox but still going to see if I can accomplish a 3d printed version just as an interesting problem to solve. You always need a printer with a larger bed size than the one you have. Maybe try the MP3DP V4 in a 600x200 size.

Thanks to all for your responses.

The melzi does not have much flash. I remember updating the firmware on it (I made a post on thingiverse with the pinouts many years ago). I had to disable a lot of features to get it to compile. It would be interesting to make it work, but it is largely academic. Even a ramps combo has a lot more horsepower. An skr turbo would be an easy replacement for the brain and give you plenty of room for any features you wanted.

THanks Jeffeb3, I have a few ramps units here if it ends up being the needed. I have see nthe same comments posted a few times. I am going to try
[Wanhao Duplicator i3 with BLTouch Bed Leveling | Yet Another Tech Blog]
which references the configuration and configuration_adv
[Marlin/Marlin/example_configurations/Wanhao/Duplicator i3 bltouch at 1.1.x · chasetec/Marlin · GitHub]
as they recon their setup will work with the SD card and the LCD and the BL Touch. I am sure there will be a trade off, but my enquiring mind is making me try it.

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Thanks Della. I have made a few printers already hence a few boxes of parts at my disposal. You are quite right, Safety is paramount especially where working with mains electricity and making sure all power supplies are well insulated and away from prying fingers.

For this new project I was wandering the payoff between building another corexy type printer with the bed lifting and lowering vs the moving Y axis and running the extruder and X axis up and down the Z axis. I made S.T.E.V.E which was a core xy and worked ok but didn’t float my boat. Had too much flex at the extruder for my liking. I then made the DashX printer which was a good solid machine but I got side tracked and it became a dual extruder until I got disillusioned with the dual print process and didn’t really have a lot of call for it so ended up breaking that up as well. Using the parts from those two projects I wanted to try and see about making a bigger bed machine. I am now leaning towards rebuilding the Dashx machine but on a larger scale.

Just finished doing the hardware modification to the Wanhao i3 and got the 3D touch fitted. Going to spend the next few days researching and sorting out the flashing of new firmware.

Funny that with all the machines brought and built, my daily go to machine is my old Flsun Q5 that just keeps going and never given me a days trouble since I learned about glue sticks. Just the bed size is small.

I am thinking more towards the MP3DP V4 machine now with a 200x 600mm bed.