The journey to convert my Ender 5 Pro to direct drive.

[Ender5r]

Well, now that my printer seems to be getting dialed in, and is printing reliably, I want to convert it to direct drive. I found a printable mount on Thingiverse that let me move the extruder from the vertical support to the hotend mounting plate. There are several aspects of the mount that I would've done differently, and might yet do, but it works, so there's that.

I also discovered that the data cable that connects to the extruder stepper motor was too short to reach it in its new location. Oops! I looked online for extender cables. There a few available, but not many, and they're ridiculously expensive, like $18 for one 18" cable. That's just price gouging. So, I found some spare 6-wire cable in my stockpile. I only needed 4 of the wires so I just peeled off the extra 2. I then got out the old soldering iron, plus small heat shrink tubing and spliced about 20" of it into the middle of the existing cable. That way I didn't have to deal with fitting new connectors.
Despite triple-checking the wiring to make sure I wasn't accidentally cross-wiring any of the 4 wires, I managed to cross-wire 2 of them anyway. I put it down to my declining eyesight. From having between 20/5 and 20/10 eyesight most of my life, I'm down to something like 20/27, with cataracts starting to form. I will definitely need surgery in the not-to-distant future.
Anyway, I left it late last night and tackled it again this morning. I did a continuity check with my DVOM and found the cross-wiring. A few minutes of desoldering and resoldering had the problem sorted.

That leaves the spool holder to sort out. The normal side mounting position is certainly not ideal for feeding a direct drive setup, and mounting the existing holder to the top of the rail the holds the Y axis motor is not possible because it's too low, which can lead to the hotend mounting running into the spool. I found a spool holder extension on Thingiverse that will lift the spool up high enough to clear the X axis altogether. The kit also includes a spool insert that's supposed to make the spool rotate easier. I'm currently printing both pieces.

I'll post some photos when I have the new pieces installed. Now, have to go to Amazon and order some T nuts and bolts.

[Ender5r]

I may need to order some extra T nuts for my Ender 5. Can anyone tell me the proper spec to search for, or even post a link to an amazon page for the right ones?

[StumblingBumblingIdiot]

I may need to order some extra T nuts for my Ender 5. Can anyone tell me the proper spec to search for, or even post a link to an amazon page for the right ones?

I am guessing as I never got any more but any 2020 t-nut should fit - https://www.amazon.com/VIGRUE-Fasten.../dp/B07PLKVW69 - for example.

[Ender5r]

Thanks, but it seems there are different sizes, so many that I decided to ask if anyone knows the exact size. As you say, the fact that they are 2020 extrusion specific does help.

[Ender5r]

OK, quite a few developments over the past 4 days:

1. I have printed and installed an adapter plate from Thingiverse to the stock hotend mounting plate;



I have discovered that the small gap between the extruder and the Bowden tube is an issue. Last night, I was printing when I noticed that the filament had skewed to the side of the tube and had begun coiling like spaghetti around the tube. I'm not sure why this happened, but it did, twice. The problem is that I can't really have a coupler in the output from the extruder because it's too close to the one in the top of the hotend. I will have to modify the adapter plate some more so the extruder sits higher and allows me to not only install a coupler in the extruder, but also makes it possible to have Bowden tubing all the way up into the output of the extruder. Hopefully, that will prevent any spaghetti action, and also help ensure I can use more flexible filaments, such as TPU and Ninjaflex. While I'm at it, I'll change the extruder mounting holes in the adapter plate to horizontal slots, so I can slide the extruder left and right to ensure it's directly over the hotend.
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2. I've printed and installed an extender to raise the stock spool holder higher above the printer, so it won't be hit by the X carriage when it 'homes';


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3. I've discovered that the extruder stepper motor gets much hotter than the X, Y, & Z motors. I don't know why this is, but it's led to an issue with the adapter plate (which is, after all, printed using PLA). If you look closely, you can see that the heat from the stepper motor has caused the PLA adapter to sag backwards.


I have several ideas of how to deal with this, including: printing in a more temperature tolerant filament; modifying the plate so it has more lateral reinforcement, so it withstands the temperatures better; adding a 40mm cooling fan to the side or the motor to cool it. This would be another mod to the adapter plate that would be where the fan would mount.
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4. I don't have a lot of metric nuts & bolts around. This led to me having to improvise. I did have the two M5 bolts and T-nuts that held the spool holder to the vertical rail of the printer. I used them to hold the extension down to the rail on the side that experiences the most load:

[Ender5r]

5. On the less stressed side of the spool holder extender, I used a couple of M5 PLA bolts I created in Fusion 360
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From the photo it's obvious the threads aren't perfect, but they worked surprisingly well, as seen here:
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6. To secure the stock spool holder to the extender, I drilled out and tapped (M6x0.6, I think) the 2 blind holes that are part of the design. I then used the 2 extra M6 bolts kindly provided by Creality to faster the holder to the extender:
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7. Finally, at the recommendation included with the extender files, I printed and am using an extra spool roller that the author says reduces the rolling friction of the spool as it unwinds:
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BTW, if anyone isn't aware, you can click on the pictures to see larger versions.

[StumblingBumblingIdiot]

Thanks, but it seems there are different sizes, so many that I decided to ask if anyone knows the exact size. As you say, the fact that they are 2020 extrusion specific does help.

The 3mm,4mm,5mm,etc would just be the screw size as the t-nut should be the same to be able to fit in the 2020 channel...?? Again I am guessing as I never ordered any but a 2020 t-nut should work in ANY 2020 rail......

[Ender5r]

The 3mm,4mm,5mm,etc would just be the screw size as the t-nut should be the same to be able to fit in the 2020 channel...?? Again I am guessing as I never ordered any but a 2020 t-nut should work in ANY 2020 rail......

Hopefully so but, of course, you do have to pay attention to which nuts to use because the hole/thread sizes change with the bolt size (M4, M5, M6, etc.)

[Ender5r]

Some more news. I gave up on the Thingiverse adapter. This happened after I found some old aluminum plate that I had stored in my garage since the 70s. It was from some shelves out of an old communications equipment cabinet. Anyway, it's good, strong stuff, but still quite light.

Here's a shot of the new plate mounted. I made it a little on the large side, in case I want to add a cooling fan. Looks like that may not be necessary: the new plate seems to keep the extruder's stepper motor much cooler than before. Nice.


A shot from the side:


A closeup of the cutout I had to make to accommodate the X axis drive belt on the left side of the plate. I don't have a band saw, so I had to make do with a jigsaw -- not fun.


A closeup of the new mounting point for the right-hand guide wheel. I was unhappy with the original location because it was located too much behind the hotend. The new hole is 20mm further right than the original, so I moved the X axis endstop switch 20mm further right.


I still need to drill a couple of small holes to attach a cable guide/strain relief. Also, I'm finding that the location of the filament reel on top of the printer isn't ideal. The filament, expecially PETG, keeps jumping over the sides of he spool. I'm thinking of using the original mounting bracket to place the spool at the back of the printer. I will need to design and print a guide bracket that will keep the filament from hitting the Y axis axle, and will guide the filament up and above the extruder.

Overall, I happy with the mods. I haven't seen any degradation in print quality, so the extra mass doesn't seem to be hindering movement of the X axis. I hope it will make printing flexible filaments easier down the road.

[PsyPhyGuy]

Fan dang tastic! Great design. Also great explanation. I have some Al flat stock in the shop. Now I know what it is going to make.

[Ender5r]

If I was to remake my adapter, or decide to modify it, I would make 2 changes:

1. I would make the holes for the stepper motor into vertical slots, wide enough that the extruder can be slid left and right, so it lines up with the hotend perfectly, but also long enough so that I could move the extruder up & down, to get it as close to the hotend as possible. I suspect this might help with flimsy filaments;
2. I would turn the hole for the stepper motor into a vertical slot as well, to accomodate the changes made for the extruder.

I've decided to leave it alone for now. I haven't yet printed any really flimsy filaments, but I will make alterations if they prove to be troublesome. Also, moving the right-hand guide wheel to the right was a good decision...recommended.

BTW, flimsy filaments should be the name of a band. "Ladies and gentleman, I'm very proud to present the hottest new group, the Flimsy Filaments!".