Upgrading to E3D Revo

Ender 3 undergoing upgrades

    Over the last year and a bit, I've been involved in beta-testing E3D's new Revo series hot-end, this is the process of upgrading my two mainline printers to run on it. One is getting my final beta hot-end, the other is getting a Revo6 I won in one of the contests E3D was running earlier this year.

 

Revo Micro on Voron Afterburner mount

    My Ender 3 got the beta Revo Micro, mostly since it was due for an overhaul anyway. Mount is the Voron Afterburner AB-BN variant, mostly since that was the only version that had proper support for the Revo Micro heat-sink in February, the current Stealth Burner had yet to be released at that point. Installation was fairly straightforward, I mostly followed the extruder assembly section in the Voron 2.4 manual, then it was just some calibration for the new tool-head and it was up and running.

 

#ShamrockE3D

     After getting it fired up, I was completely shocked by how good the print quality was, the image above is done with the 0.25mm nozzle, and aside from some light stringing, the print is basically perfect other than some ringing artifacts that are more to do with the printer frame than anything else. Incidentally, this print also won the random draw in #ShamrockE3D contest, netting a second Revo Six hot-end, so it was time to refit the Sculptor.

 

Revo Six on Bear Extruder

     The Sculptor had been overdue for a rebuild on its tool-head for about 6-months now, so I decided to make the conversion over to using the BearEXXA project, the same as what I'd fitted the Mendel90 with last year. Once the new printed parts where assembled, the Revo Six was a snap-in upgrade, it fits the old V6 mount design perfectly. One thing that I changed from normal assembly was adding a length of M3 rod-stock to extend the x-axis cable management tail, mainly to protect the Revo electrical quick connects, the Molex Micro-Fit 3 connectors are a known weak-point for stress failures if bent by gantry movement. The other tweak I made was installing BearEXXA Delta P v2 Fanduct, mainly due to the BearEXXA stock ducting being rather overdue for an update.

Revo 6 with Delta-P ducting

     Once I'd gotten the updates fully dialed in, the jump in quality was frankly night and day, probably a combination of the high-performance heat-break on the Revo systems along with substantial upgrades to the part-cooling setup on both printers. And with the new high-flow and hardened nozzle-cores that have just been announced, I'm looking forward to years worth of fantastic prints out of both machines.

 

Ender 3 on left, Sculptor on right

Upgrading the Sculptor: Bondtech BMG gearing, Silent fans, and Thermistor replacement

Sculptor ready to print

    Time for some 3D printer upgrades! This time it's the Sculptor i3MK2.3 under revision, specifically the print-head assembly. After refitting my Ender 3 with Bondtech gears during the early fall. I was quite impressed with how reliable they after a couple hundred hours of printing. So when a decent quality clone of the BMG turned up on Amazon, it was time for a much needed upgrade and overhaul for my second oldest printer.

E3D Thermistor and Capricorn XS PTFE tubing.

New (top) and old (bottom) E3D thermistors

   First step of the upgrade process was to strip down the existing tool-head and check the electrical parts for any issues that may have come up over the last year or two of use. One issue that I'd been aware of going into this refit was a bad bearing in the hot-end fan, but as soon as I removed the part fan it became clear that there was a major safety issue with the thermistor cartridge, specifically that part of the insulation had frayed away from the wires it was supposed to protect, that could cause a fire if the control board glitched at the same time, so getting a replacement became the top priority for this upgrade cycle. Fortunately it turns out that E3D had already fixed the manufacturing fault that caused the issue, so I ordered a couple of the updated version, one as a replacement and one spare for future repairs.

Secondary extruder gear installed on idler arm

    Bondtech actually has a specific kit of the BMG that is meant for refitting an i3MK2, so there are SLS optimized source files to work from for the printed parts, fortunately I found an FDM optimized remix on Thingiverse (thing:3347150), so it was just loading the parts into a batch on one of the other printers, cleaning off supports and starting assembly using the online instructions from the official kit as a guide on what goes where.

Gearing system half installed on motor

Assembled Tool-head bolted onto gantry

    Once the mechanical assembly was done, it was time to sort out the electrical issues that had cropped up. Since I had the tool-head apart anyway, the hot-end got stripped down to components and refitted with new parts, Capricorn XS PTFE for the barrel lining, a fresh nozzle and the replacement thermistor, all fairly simple refits but you do have to dismantle the lite6 hot-end to do them. With that side of things done, it was time to deal with the worn out fan.

Fractal Designs Silent Series R3 4010 12V fan

     My local computer store turned out to have some nice 4010 fans from Fractal Designs in stock, so I picked one up to test it out and see how it compared to the Noctua model on the Mega Kossel. Visually, they're quite different, the Noctua has a smaller core with larger blades whereas the Fractal looks more standard, but sound-wise they're about the same when powered up, so I'm fairly happy with the Fractal Designs model and I'll probably be using them in future refits.

Fractal Designs fan installed and ready

     Once all the fans were mounted, it was time to calibrate the extruder and do a test print. Instead of the usual 3DBenchy, I decided to try the Lattice Cube by Lazerlord (thing:1850320) and see how it turned out. 6 hours of overnight printing later, I was greeted by a nearly perfect print when I came into the workshop to check on it. Overall I'm expecting this upgrade to keep the Sculptor running reliably for several years to come.

Lattice Cube freshly printed

Building a Prusa i3 MK2 from Scratch

Prusa i3MK2 'Sculptor"

    So, time to reveal what the mystery replacement for the Micro Kossel is, I've repurposed the electrical harness into a Prusa i3MK2 clone build. Sourcing the parts was a bit of a nuisance, but most of it had close matches at my local hardware store or was stuff I had on hand.

Imperial equivalents of the M8 (5/16") and M10(3/8")
 with 1/4" threaded rod for the z-axis screws

Idler arm for the extruder with a 625 bearing from OpenBuilds

     Now, some of the parts for this machine do require CNC cutting normally, but following some of the tricks used by Tom's 3D build from march, I printed the frame template on paper, glued it onto and cut it out from some 3/4" plywood for the frame and 1/4" plywood for the y-carriage.

3/4" plywood frame with template attached

Frame and y-carriage ready for painting

     After cutting out the wooden parts, the next step was to paint and seal them, otherwise they'd change size with the ambient humidity. I used some black acrylic for the first coat, then followed up with a coat of Varathane to seal them.

Main frame waiting for paint to dry

Y-axis parts and tools

     While waiting for the paint to dry I moved on to assembling the y-axis/base frame. Assembly is fairly straightforward, only major thing that you need to watch is that the frame is completely square and flat. Squaring the frame is fairly simple with an old woodworking trick, just take a tape measure and check that both diagonals are the same length, if they match the frame is square in that plane. As for making sure it was flat, I used the one surface in the workshop guaranteed to be perfectly flat, the top of the table saw.

Checking the diagonals for squareness

Checking the other diagonal

     Once that was assembled, the next step was adding the vertical frame, then installing the x/z-axis assembly followed by the extruder carriage to complete the primary frame assembly.

Main frame assembled

Extruder ready for installation

    With the Extruder installed, it was time to sort out where to mount the main control boards. The normal place for them is on the back left of the main frame, but the cables on the LCD module I'm using are only 10cm long, so I've mounted the Ramps package on the front left side with the power block on the back.

Installing the Ramps casing (Thing:761806)

Power brick with custom brackets

Raspberry Pi Zero W for Octoprint host

    I designed a couple custom L-brackets for mounting the power supply and Pi camera, with those installed, it was time to sort out the firmware and calibrate the z-height. For the print-bed, I'm just using a sheet of Buildtak stuck to some 3/8" plywood, basic but workable.

Completed i3MK2