Walter’s Modifications part 4 - CoreXY conversion

[Walter]

No I didn't consider that option.Too expensive in transport and customs
But i did have some fun in desiging and building this one with the restrictions I imposed myself.
It's meant for smaller parts and yes : from scratch to 'working' in less then 2 weeks is quite quick with a full time job AND a wife!

[Ron]

I like that.
I have almost collected enough spare parts to build another printer.
One of these days........

I am curious, how big is the build plate in that printer?
It looks to be around 120mm square, and is it heated?

[Walter]

As I did !
I bought a standard prusa-style MK3 heated bed. Size 215x215 and heated (12 or 24V).
Since I used the original 12V 30 amps power supply, I added a MOSFET switch to get the high currents off the board.
I didn't really optimize as I wanted a compact printer able to print the easy stuff and 'normal' sized parts.
Usable bed surface : 170x170mm. I could squeeze out the 200x200 by making the frame wider.
Usable height is 220mm.
Probably I will throw the the components on Thingiverse, but since I made a lot in alu profiles (the whole bottom and printbed support) this will something for the more 'advanced' builders.
Some of the them are already there. The Z-endstop, the Y-endstop, the bed holders and -adjusting knobs

[Ron]

Very interesting.
Thanks!
I think there may well be a mini FT-5 in my future as a backup printer.
215x215 seems like a good size and would meet the vast majority of my needs.

I used the original FT 12 volt PSU for another project (non-3D-printer-related).
However I have another nice 24 volt supply on hand and so I would just go with it.

I have spare motors, extruder parts, hot end parts, a display, cables, idlers, fans, and much more.
All I would really need to buy are the bed, some framing pieces, belts, pulleys and a controller board.

I am thinking in terms of scaling down the dimensions of the FT-5 proportionally to fit the smaller bed and building a generous electronics enclosure in back as you did.
I'll bet it would be very rigid and could handle very fine layer heights.
I have metal-working tools so metal work is not an issue (I did notice all your nice metal parts).

Hmmmmm..... this could be a lot of fun.

(so far no pestograms.......)

[Walter]

Some more detailed pictures (Not necessary in a logical sequence ...):
Y-stop mount and adjustment screw on the bed assembly

Carriage. Build around a couple of LM8UU's. Alu mount for the E3D hotend and heatsink. electrical connections on the back and a microswitch build in on the right as X-endstop.

Z-endstop on the left vertical 2040

Carriage seen from the left with the partcooler

Topview of the carriage. On the right the X-endstop. On top 3 leds as indicators for fans and heater. (I like LEDs )

Rear view

Rear view of the left side

Electrical connection and partcooler.

Top view. With both Z-steppers and extruder. I wanted to install only One stepper, but lacked the right size of belt. Reused the 2 smaller belts from the FT5 for this.

Left side view

View on integrated the X-endstop

Low rear view

Z-stepper assembly

larger rear view

Top rear view

X-stepper mount

Y-endstop and base mount

Side view on the top mount

Power supply is mounted on an alu sheet (1,5mm thick) to the base ad side profiles

View on the bottom side of the X-Z connection block with the threaded rod screw and Z-endstop

[Dave]

I think there may well be a mini FT-5 in my future as a backup printer.215x215 seems like a good size and would meet the vast majority of my needs.
...
I am thinking in terms of scaling down the dimensions of the FT-5 proportionally to fit the smaller bed and building a generous electronics enclosure in back as you did.

I've often thought the exact same thing... Something similar, but more desk friendly.

But then I remember how much I've wanted to change things, experimenting with the FT-5, that a "Mini FT-5" the way I wanted it would basically just be a Hypercube or the like.

[Ron]

@walter
Wow!
Thank you so much for the photos.
That inspires me to start planning something.
Unfortunately, I am spending far too many hours at work at the moment to allot what little free time I do have to such a project, and I am likely to be doing so for at least the next 2-3 months.

Question- Is the guide rod setup stiff enough for the X axis?
I am thinking that I might still want to go with ball slider rails (like the FT-5) even if building the same style of printer as you did.

But then I remember how much I've wanted to change things, experimenting with the FT-5, that a "Mini FT-5" the way I wanted it would basically just be a Hypercube or the like.

Well, yes more or less.
But I do think it could be made better or at least different.
For example this is what I would want to do-
* child-friendly (no pinch points, hidden wiring, few if any periodic adjustments)
* the most compact envelope size practical with a ~220x220 bed plate and perhaps ~250 build height
* minimum number of printed component parts
* one motor each for X, Y, and Z
* ultra rigid frame perhaps re-using the old FT-5 T and L plates (why not?)
* easy printed part access from the front (homing to the back and build platform down for example)
* fully supported and guided build bed (no cantilever)
* integral lighting
* high up display
* reverse Bowden feed with an integral filament reel holder and brackets
* 24 volt operation from the start
* large, fully enclosed electronics box at the back, especially the AC portions
* true auto power-off at the end of the print
* a decent part cooler
The challenge and fun (for me) would be to build it from things that are literally just laying around collecting dust.
And also to do it for the minimum possible cost "just because".

"Desk friendly" is a key consideration in my situation too, mainly because I would likely give it to our son and his family when it was completed and thoroughly debugged.
They have less available space than we do.

[Walter]

Answer to your question:
Yes absolutely stiff enough. 2x 8mm rods.32mm apart around 20mm inserted in the ZX-connectors. And not much weight to carry.

Only 7 structural plastic printed parts. Base and top part, ZX-connector and carriage. The vertical guides are with LMFLUU bearings pressed in the ZX-connectors like in the FT5.

[Ron]

Thanks, that is good information.
The rods are certainly less expensive than ball slides.
So perhaps that would be the way to go.

As for minimizing the printed parts, it is only a personal challenge I am giving myself.
However, if going with rods at least some printed parts become a virtual "given" (to minimize the moving mass).

Something to ponder.

Yours seems like it is a great little printer.
Thanks again.

[Walter]

Some more details of the construction of the bed (had to remove it to dismount the burned MKS ...)

An I use these instead of a nut in an insert if it fits in the design (Works really good!):

[Ron]

Nice!
I like the captive nuts.
I have used similar things in building furniture and they can be a real blessing.

So....... when are you going to start offering kits for sale?

I am really getting enthusiastic about building a "junk box mini-FT-5".
I think I will call it an FT-2.5.
But as I mentioned earlier it will have to wait 2-3 months until I have enough free time.

[Walter]

I like the captive nuts.

I used them (size M4) in the carriage to mount the alu-profile for the hotend. Doesn't move at all. Part is printed in PETG. 0,4mm layers. Easy and no worries

[csorrows]

@Walter, this has gone way OT. The I3 build should not be in the Ft-5 section.

I'm not trying to be mean but yea.

[Walter]

@csorrows : yes you are right. It all started as a kind of fall back project while preparing the coreXY-mod..
Just in case I would have to reprint one of the more complex items that I couldn't easily make otherwise.
I don't want to justify myself, but it's one of my bad habits : sharing with other people..I will publish that on thingiverse once it's working fine. That's the better platform.
Thank you for keeping me on the lane!
Next post will be about the (real) CoreXY mod.

[Dave]

The large knobs do indeed make adjustments very easy. I struggled with smaller (or no) knobs for a while and finally just printed up the ones shown in the photos.I like them very much.As for fine adjustments, well yes and no on the bed springs.Once the bed is leveled it is preferable not to mess with them (especially if you have the belt and bearing setup I have so everything stays level).So the end stop for Z becomes "the" adjustment that controls height.Using these knobs I am able to tune in very fine changes if needed.And yes, it also makes things easier and faster when I change nozzles or build surfaces.I know that you are supposed to be able to do changes of that sort through the display, but for whatever reason the Z offset setting doesn't work effectively on my printer.So I just tweak the height as needed using the knobs.It is faster and easier.FWIW.......

Thanks for this info. It made sense when I read it at the time, but it didn't really soak in until I started printing with different materials and changing back and forth. Now I completely understand. And I have an adjustable Z endstop printing as we speak.

[Ron]

Yes, they seem like such a trivial thing until you have them..
Then they seem more like a necessity.

I used a slightly modified version of the bed-mounted bracket from @csorrows's Z stop set and designed a top bracket of my own because of the E3D parts and their different stack up height.
When I have on occasion switched between long and short hot ends and different mountings for them I use a 1" long aluminum spacer that I can add or delete to the end of the screw to gain a wider adjustment range.
I already had used the longest M3 threaded screw I could find.
Once you get the bed plate stabilized (in both the X and Y directions), you won't have to adjust the Z stop much, and the bed leveling springs only rarely.

To keep the thread on track, perhaps this would be a good addition to @walter's setup?

[Walter]

good addition to @walter's setup

For the moment I will continue to use the BLTouch. Works fine and even with a level bed : It's the endstop at the right place.

I installed the new MKSGEN 1.4 on my quick and dirty printer. I am not used small prints taking over an hour to print. A 0,4mm nozzle and 0,1 or 0,2mm layer heights are not my thing. But... Now they can print somewhere in the corner, while printing the 'real' stuff on my FT5
Here is a video of the very first print (0,1mm layers, 10x10x30mm). Really nice! But taking so much time.

[csorrows]

I don't want to justify myself, but it's one of my bad habits : sharing with other people..I will publish that on thingiverse once it's working fine. That's the better platform.Thank you for keeping me on the lane!Next post will be about the (real) CoreXY mod.

I love that you share and will always encourage you to do so. I would also love if it was in the correct category and the thread stayed on topic. People seeing your title and expecting to read about your coreXY project might not be interested in another project. Keep in mind, this forum is just as much a resource for other users as it is a place to get direct help. Keep up the great work.