A few questions before starting

[The-Techy]

Hi,

Recently came across this printer, and it looks super interesting. I have an old Ender 3 lying around that I want to use for a project, and this seems pretty perfect. I've already seen this discussion post with some design changes to use Ender 3 parts, which is super useful, but I had a few more questions, and it would be great to get some answers.

First, I assume I can reuse stepper motors, aluminium extrusions and power supply from my Ender. There's a few parts I'm less sure about though. I have the Creality 4.2.7 mainboard, guessing I can't use it since it only supports 4 steppers but want to make sure. There's also the extruder - obviously the BIQU H2 V2S is the one used here, and it's quite different to the Enders one (not least of all because it's direct drive and Ender is Bowden), so no way to reuse that? The X and Y carriages are presumably out too. But can I use the belts, pullys and idlers? At first glance they seem to be the same, or similar. And I see the design uses a switch for levelling - anyone know if I could use the limit switch from the Ender? Anything else I'm missing?

For the bed, what material is going to be best? I've seen tape on the aluminium and textured PEI (from a delta printer?). I have the knockoff build tack surface that came with my Ender which I could probably cut to size, or is tape going to be simpler and easier? Similarly, is a heated bed going to be worth it? My plan was to build it without, but I know that can cause issues (and rules out some surfaces e.g. PEI). I've also seen various plates on Aliexpress that promise perfect adhesion without heat - I wonder if those would work.

Mainboard - is any RepRap supported board with at least 5 stepper drivers fine? Seems to be a few cheaper options out there than the one in the BOM. Also, I've only ever used Marlin, is that likely to be an issue?

Is printing all the parts out of PLA (except extruder mount which I'll probably get metal 3d printed) fine? Only ever used PLA, if it's not ideal maybe this would be a good excuse to finally try some other materials.

Is the current BOM everything you need? I know some people have been working on updated versions, but if I follow the current one, is there anything missing?

And finally, does anyone (aside from Joshua) actually have one of these built, and printed something with it? Just want to make sure I'm not wasting my time too much (though I know this is doubtless going to involve a fair bit of troubleshooting, and not a ton of printing).

Thanks!

[oldnslow]

See Team Gloomy Supported Main Board list here for non Duet 3D boards that have RepRapFirmare (RRF) support. 5 stepper drives is indeed the minimum requirement.

As RRF natively supports the kinematics required for the Core-R-θ, it is the only practical option at this time. Installing RRF is fairly straightforward see the Team Gloomy instructions or this work in progress Wiki specific to the Core-R-θ. Although the RRF GCode approach can be a bit cryptic at first, it allows for simple tuning, tweaking and development. The GCode Dictionary is a handy resource and there is a long running forum as well as the Team Gloomy/RRF discord.

A more comprehensive BOM for the original jyjbird design can be found here, should be pretty complete but is untested - will finalize when i finish building in a month or so! If you methodically go through the discussions and issues, there are some good mods and component sources provided by those who have already built or are currently building a Core-R-θ.

As Joshua has noted somewhere in the discussions/issues (which are searchable), PLA is a suitable material.

Extruder type and reuse of your other Ender components is limited only by your imagination, ingenuity and understanding of printer configuration setup.

[jyjblrd]

This is a great answer and covers a lot of the main points. Some quick things to add from my side:

There are a few threads on here about heated beds. Personally I decided against adding one as this printer is just a prototype and I wanted to keep the complexity as low as possible. Also I only really print with PLA, and good old painters tape has always worked fine for me.

A few people have successfully built this printer, with their work documented in this forum. It's definitely possible to build, but you're right to expect quite a bit of troubleshooting :)

[the-Geeson]

I bought an Ender 3 Just for this project, this is where Im at;

As for the steppers, In the end I only used 2 of the four stepper that came with the Ender 3, I swapped out the two stepper moters that go in the Z carriage, where the cables come out of the steppers is blocked by a wall. I ended up subbing out those steppers longer ones, I did modifly the file in Fusion360, but never printed it. As for the Z moter, the Ender 3's lead screw is 150mm longer then then Z rails, so I just used 40mm standoff to have the coupler hang above the moter mount.

Some of the aluminium extrusions will need cutting down, both the 2020 and one bit 2040, I used some of the tapped holes as fixing points insted of using Tee nuts.

I did buy the H2 V2S as im not a huge fan of Bowdens, but I do think you could use the bowden from the ender 3, If you cut down the bracket, It MIGHT fit behind the Z moter, see below for possible cut lines.

Belts, pullys and idlers:

The Ender's belts are not loops, they just have each end fixed to the carriage they are moving, your best swaping them out for looped belts,

For the pullys, the ender 3 only has 2 pullys, and those are press fit onto the X and Y moters, on the C axis (bed) the pully will fit though the hole in the base, on the Z carriage however needs the pullys remove to fit. I ended up having to cut one of the pullys off the moter to put them into the Z carriage, so I ended up needing 2 new pullys.

In the end I just ordered new belts, pullys and idlers all from the same seller.

for the leveing switch, the ones off the Ender 3 should work, It just will need a new braket to fit the board or you can unsolder the switch from the board aswell.

for the bed I was just going to use a no headed aluminium bed and tape, but looking on Aliexpress, I did find a 240mm round head bed cheaper then bare aluminium that I could get local, so I have ordered that and a slip ring to have the option of heating the bed

Ive printed all my parts out of PETG but PLA should be fine aslong as it doest get too hot