Guides

Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

I wanted to try out the Sherpa Mini extruder for a while now, so I installed it on the FLSUN Super Racer. In this article, I will show you how I upgraded my FLSUN Super Racer to Direct Drive, and how I tackled the Sherpa Mini installation.

Why convert the FLSUN Super Racer to direct drive?

I was pretty happy with the stock extruder setup on the FLSUN Super Racer but I wanted to convert it to Direct Drive because you get better filament control in this setup. Besides that, you also eliminate some of the annoying retraction noise caused by the stock extruder, and TPU can be printed easier.

Here’s a quick test I did using the Sherpa Mini. I was able to print Polymaker PolyFlex TPU95-HF at 100mm/s with ease, and that was before doing any kind of calibration. I will share more prints and videos soon.

Here are some images with the end result:

You might think that the Sherpa Mini installed on the Super Racer effector will make it heavy, but in my configuration it sits at ~370 grams which is not that bad. I think it’s worth the weight increase considering the benefits of having a direct drive extruder. Besides that, the added ringing will be fixed with Input Shaper.

Sherpa Mini on Super Racer weight | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

Prerequisites

To install the Sherpa Mini on your FLSUN Super Racer, you need to have the following:

  1. Sherpa Mini extruder
  2. Printed mount
  3. Spare M3 nuts and bolts
  4. Super Glue
  5. 5015 fan with printed mount (optional)

Before you begin

Before you begin

Please note that converting your FLSUN Super Racer to direct drive requires some experience with 3D printers and hardware. This is not a trivial task for beginners, and you may break your printer during the process.

Read the full guide carefully and follow this guide only after you properly understood all the steps involved. If you have questions before starting, leave a comment and wait for a reply.

I am not responsible for any damage you may cause to your printer by following this guide. You are doing this on your own responsibility.

Steps to install the Sherpa Mini on FLSUN Super Racer

Remove the effector from the printer

The first thing you should do is to remove the effector from the Super Racer. This will allow you to easily disassemble everything and install the Sherpa Mini.

Flsun-Super-Racer-Effector-1

Disassemble the print head and remove the old metallic mount

I removed all the fans, metal housing and the fan ducts. In this image the PTFE coupler is still attached, but remove that too. You won’t need it with the Sherpa Mini.

FLSUN Super Racer Effector without housing | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

Attach the mount to the effector

Attach the printed mount to the effector, then attach the part cooling fan. Don’t overtighten the screws for the fan because you can easily strip the plastic and the fan won’t be securely attached.

Sherpa Mini printed mount for FLSUN Super Racer | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

Attach the Sherpa Mini extruder to the mount

Now, you can install the Sherpa Mini extruder. I used a 24mm PTFE tube to guide the filament from the Sherpa to the hotend, but your PTFE tube size could be different. I have a bi-metal heat break installed which is different compared to the stock heat break.

As usual, don’t overtighten the screws which keep the Sherpa Mini attached to the printed mount. Tighten them just enough so the extruder is fixed and does not move.

To avoid issues with the SLS printed sections of the Sherpa Mini, I also used M3 washers to protect them

Metal washer for Sherpa Mini | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

Attach the fans to the printed mount

You can use the stock fans and install them back using three M2 screws for each fan. I didn’t trust the M2 screwed in the plastic mount, so I just super-glued the fans to the mount. I know that this is not really the best way, but if something happens, it’s easy to just re-print the mount and add new fans.

Sherpa Mini on FLSUN Super Racer | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

I had dual 5015 fans with the bowden setup, but now I use one of the stock fans and a single 5015 fan due to space limitations. Even in this setup, the part cooling performance is good enough, and a decent upgrade compared to the stock dual 3510 fans.

Install the effector to the printer

With the Sherpa Mini installed, you can attach the effector to the printer and do some wire management. You could route the motor cable trough the wire loom but I was a bit lazy and I just routed it over the mesh. This allows me to quickly remove the Sherpa if I want to do it in the future.

The motor connector goes in E0 port on the board.

IMG 2039 | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

Update the extruder configuration

As you know, I use Klipper on the Super Racer, so updating the extruder configuration took me less than 30 seconds. This is the config I used:

microsteps: 16
full_steps_per_rotation: 200
rotation_distance: 22.67895
gear_ratio: 50:10
Extruder config with Sherpa Mini | Sherpa Mini Direct Drive Upgrade for FLSUN Super Racer

My Trianglelab Sherpa Mini came with the LDO-36STH20-1004AHG(XH) stepper motor which allows me to use a vref value of 0.850.

[tmc2209 extruder]
uart_pin: P1.8
interpolate: True
run_current: .850
hold_current: .500
stealthchop_threshold: 100

Calibrate the extruder

As usual, after changing the extruder, it’s recommended to calibrate E steps and flow rate. Besides that, I also recommend calibrating Pressure Advance and Input Shaper to ensure that you get the most of your new Sherpa Mini Direct Drive extruder setup.

Wrapping up

I hope this guide is helpful to you. Upgrading the Flsun Super Racer to direct drive was easier than expected and I am quite happy with the results. I am sure we’ll have a dual 5015 fan mount soon which works with the Sherpa Mini, so I’ll update the article when I do that upgrade. Until then, enjoy your new Sherpa Mini!

You can also join theΒ 3DPrintBeginner ForumΒ where there’s a dedicated thread for FLSUN 3D printers.

Liked it?
Consider supporting 3DPrintBeginner if this content helped. You can also join Patreon for exclusive perks!

Related Articles

Latest Replies

  1. Avatar for Mykado Mykado says:

    Why are you using run_current: .850?
    I ask because when i run this on my mini sherpa for the SR, it gets really hot.
    I was reading somewhere that a current of .3 or .4 would be better?
    i havent tested yet, i wanted to hear your thoughts first

  2. Depends on the type of motor you have.
    Find the exact part number written on it and do a search online.
    I can’t remember the exact value used, but I did the same and found the value.

You can leave a comment for this article on the 3DPrintBeginner Forum

Participants

Avatar for 3DPrintBeginner Avatar for Mykado

16 Comments

  1. Hi everyone, I’m making the mod with the sherpa mini, but when I bought it it was only available with the moon motor.
    Could someone help me by providing me the vref because I can’t find it online.
    Thanks in advance, congratulations for this guide!

  2. hi, what bi-metal heat break di you use in your configuration on flsun sr, can you provide a link? did you have also other differences from the stock hotend?
    Anyway thanks a lot for your guide πŸ™‚

  3. Hello. I have managed to mount the two 5015 fans but I have the problem that they do not start up, I assume that they have to be mounted on FAN1 AND FAN2,
    can you help me with this?

  4. Hi,

    I just installed my Sherpa Mini and it works.
    But its getting really hot because i forgot to change the vref settings.

    honestly i dont understand how i change it , and why you change it the way you did.

    Here are the values i found online by searching for the datasheets of the original, yours, and mine (cause i got a different one)

    Original (42shdc4047z-23sy)
    3.96V | 0.9A

    Your Sherpa (ldo-36sth20-1004ahg(xh))
    2.1V | 1.0A

    My Sherpa (g36hsy4405-6d-1200a)
    2.4V | 1.0A

    M906 values i found with pronterface
    T0 | E1250

    i dont understand why you chose a vref of 0.850, and also dont know how i change it. Also why is the default value E1250? is this the current it runs with? if it is why is it higher it should be?
    I run my printer with Octoprint and configured the estep value with pronterface.

    can you help me?

  5. “Mini Direct Drive”

    Admittedly, you got it wrong when it comes to what “direct drive” really means. They way 99% 3D printer lovers use for “direct drive” is … technically wrong or, at least, incorrect. Direct Extruder (or Direct Feed, to be accurate) is not the same than Direct Drive extruder.

    See https://www.matterhackers.com/articles/extruders-101:-a-crash-course-on-an-essential-component-of-your-3d-printer for a crash course covering the BASICS you should already know.

    TL;DR : a direct extruder is not necessarily the same thing as a direct drive extruder. A direct drive extruder just means that the filament drive mechanism is directly mounted to the motor shaft. Both bowden and direct extruders can be direct drive.

  6. I installed the Sherpa Mini and adjusted the vref to 0.3V. The Sherpa Motor is getting still very hot!
    Any ideas?

  7. I coincidentally did an almost identical upgrade to my week old SR a few days ago using that same mounting block on Thingiverse. I had ordered a FYSETC Sherpa Mini from Amazon in anticipation of your guide coming soon (after seeing your SR Sherpa TPU video hit YouTube)… but got suddenly motivated to give it a try myself after having troubles with the stock BMG clone jamming. Now that your guide is up, I’m glad to see your take on it!

    I’m running the stepper at only 350mA based on some other posts I found, but will give 850mA a try as you have… since it’s not even getting warm at 350mA. Apparently the FYSETC Sherpa doesn’t use a genuine LDO stepper like yours did, so we’ll see how that goes.

    Mine came with a long stepper extension cable, so I ran that up to the mainboard and shortened the stepper’s cable so they can be unplugged along with everything else to remove the effector.

    The hexagonal filament holes on the FYSETC Sherpa were impossibly tight with both the included PTFE tubing and the Capricorn PTFE I ended up using. I had to smooth them out a bit with a drill to get the PTFE in there. Since I still had a lot of Capricorn PTFE left over, I used a 6″ or so piece instead of the short one at the top of the Sherpa and zip-tied it just above all of the hotend plugs (similar to the stock FLSUN instructions)… this seems to help hold those plugs and wires up out of the way of tangling with filament.

    I should be using washers on the Sherpa mounting bolts as you did. πŸ™‚ I’ll add those next time I work on it.

    I ran into the same issue with only one of those 5015 mounts fitting, but ended up going back to the dual 4010s for now because of the way the single 5015 mount blocks the tension thumbscrew. I’m thinking to try my hand at remixing that mount block with integrated 5015 mounts that angle outwards, and maybe an ADXL345 mount too… unless someone else beats me to it πŸ™‚

    I’m really happy with the results so far. Next steps are getting Klipper going on this SR’s MKS Robin Nano and trying input shaping! Thanks for the guide, especially the detail on the Klipper config changes!

      1. I did try 850mA on the FYSETC Sherpa’s unlabeled stepper… and it started making high pitched noises once energized. It also got pretty hot quickly. As I lowered the current, the noise and heat got less intense. Right now I’ve got it running at 450mA with no noise and only warm to the touch while energized. Trying some prints now to see how that runs for an extended period. The Amazon listing for the FYSETC Sherpa actually does specify 350mA for the included clone stepper.

        The latest stock Marlin firmware supports adjusting the current via the M906 command, e.g. M906 T0 E350 to set the extruder stepper current to 350mA.

        Based on that experience, I went ahead and ordered a real LDO 20mm stepper from AliExpress as linked in your guide and plan on swapping that out. I’m hoping the higher-spec’d motor will come in handy once I start pushing the print speed.

Leave a Reply

Your email address will not be published. Required fields are marked *