Mellow Fly LLL Pro Filament Buffer

[mvdveer]

Well had some free time and decided to build the Filament Buffer. The plan is to add one each the to Mercury one, VZBot and the Two Tridents. As both of the Voron 2.4's have a BoxTurtle Unit, they already have a filament buffer fitted. Nothing as complicated as this one though.

Ordered the kits from the Mellow Store on Aliexpress. Had some issues as out of the 4 kits ordered, only one was delivered. However Mellow was pretty good and express mailed the remaining three units.

The documentation on the build is not the best, comparing to the Voron or  BoxTurtle manuals as an example. There is also an instructional video from Mellow. This build diary is my personal take on interpreting the instructions from both those sources.

What's in the packet?

Plus a wired limit switch which did not make it into the photo.

What do you need to print?

Just remember to print two of the buttons.

HEATSERTS:

The documentation does not show all the heatsert to be inserted. So, here is what the parts need to look like after installing both the M3 and the very tiny M2 brass heatserts. (11 x M3 in total and 7 x M2

  

M2 - Heat Insert

On with the build. 

Assemble the gear to the motor (Remember Locktite for the grub screw) and insert motor in the main part. Secure with two M2.5 x5 screws.   Note the orientation of the motor wires.

  

The documentation next calls for installation of the limit switch, whereas the video moves on to the PCB, which I have done. The board will be secured with four M2 x 5 screws

Slide the board in at an angle and secure.

 

Next the limit switch. This is secured with two M2 x8 screws. Not the orientation of the microswitch.

       

At this point I connected the motor and limit switch to the board

  

 

Next:  The filament slider and onwards............

[mvdveer]

FILAMENT SLIDER

Next was to install the slider that triggers the microswitch if the filament runs out. The most fiddly part was the installation of the tiny spring onto the slider.

   

Slide this into the slot where the microswitch is situated and make sure it triggers the switch:

Assemble the filament block. 

     

Insert at an angle, fitting the tube to the filament exit hole on the main part, then seat and fix with two M3x8 screws

        

Install the slider into the main part.

First install the tubing into the hole in the main body. 

Assemble the printed part to the slider

.

Slide the assembled unit over the tubing and make sure it moves freely. Not the flange of the slider needs to travel below the sensors on the board.

     

Secure the slider to the main body with two M2.5 x 5 screws

      

Make sure it moves freely

 

Install the small spring by firstly hooking it over the printed pedestal on the main body

  

Now with a M2x5 screw, hook the loop of the spring and fit to the heatsert on the printed slider

Fit another M2x5 screw into the plastic post

 

 

Next - Let's finish this......................

 

[mvdveer]

FILAMENT BEARINGS

Install the filament guidance bearings

 

 

This is the sequence of the parts to be assembled

 

   

 

Fit to the main body

 

 

Assemble the main gear - Remember - grub screws tend to loosen over time - use a bit of locktite now

 

     

 

Install into main body

 

 

Assemble the idler gear.

 

  

 

Slide the rod in from the side and fit the assemble part to the main body with the M3X30 screw

 

   

 

 

Fit the tension control screw

 

 

      

 

I fitted the pneumatic couplers at this point but it can be done at any stage

 

     

Last steps on assembly - fit the buttons and the cover. This was a bit tricky as the documentation wants you to balance the buttons on the two black posts from the switches on the PCB. This is impossible. The easiest way I found was to install the buttons in the lid and then angle it onto the main body

  

 

 

Secure the lid with five M3x8 screws

 

 

 

Well, not only did I build one, but as said at the start - I built four:

Hope this may help someone.

Thanks for reading

 

[TitusADuxass]

Somebody's  been busy.

Nice posts.

Thanks for sharing. 

[therm_virtual0y]

Yes nice post!  I have three of these but then realized I could use my already installed PicoMMU with Happy Hare and it follows your extruder to help with long runs during printing.  The Pico wasn’t working correctly with OrcaSlicer anymore unless I went to an earlier Klipper build.  As the great Stan Lee said, “Excelsior” or “Onwards and Upwards”!

[PFarm]

@mvdveerI'm trying to find the STL for the Pro Buffer. Do you have a link? 

[mvdveer]

10 hours ago, PFarm said:

@mvdveerI'm trying to find the STL for the Pro Buffer. Do you have a link? 

I have attached the files I have - don't have any links. Downloads in two posts. (size constraints per post)

Post 1:

Improved Mellow LLL Filament Buffer.zip Redesigned Mellow Filament Buffer 2.zip

[mvdveer]

 

I have attached the files I have - don't have any links. Downloads in two posts. (size constraints per post)

Post 2:

 

Penetrator Files.zip drive-download-20251220T215022Z-3-001.zip

[mvdveer]

Just some links I have:

Configuration

Mellow Documentation

Fly Buffer Download

 

[PFarm]

@mvdveer Thank you!

[PFarm]

@Penatr8tor I assume you made some changes to some of the parts? 

[Penatr8tor]

2 hours ago, PFarm said:

@Penatr8tor I assume you made some changes to some of the parts? 

The files of mine that @mvdveer posted doesn't include a part that I modified for better printing. I added some angular faces to the spring mount, the slide mount and sensor tab so that it could be printed without supports. I didn't want to put it out into the world without first testing it. So here I am now... uploading it to this post. You want to print it 180 degrees from what's depicted and you won't need any supports, it also works perfectly.

Buffer Tube_Mellow LLL Filament Buffer v2.stl

 

[PFarm]

@Penatr8tor Thank you, I've downloaded your mounting bracket from another thread as well 

[NikosSprocket]

@mvdveer these are great info.!

I downloaded the zip files as these installation PDFs they do not exist anymore, or I could not find them anywhere.

All the "official" info. on LLL Plus are I have used, are located at FLY-LLL PLUS Buffer (the URL has some ASCII codes; these are Chinese characters!)

Btw I just noticed they have a newer Firmware 1.1.5 but no info. on what's new. I know 1.1.4 had a great feature that when there is no filament in the LLL Plus and you “pushed” some new filament, the motor will start without any buttons and keep feeding filament until it "hit" the extruder! Attached the firmware bin below. Updating filament instructions here.

One day, I would like to modify the LLL Plus case to handle all internal and external cables more ... elegantly!

buffer_v1.1.5.bin

Edited April 21 by NikosSprocket

[TonyN]

More information here than anywhere else I can find on this buffer! I bought one, that was parts, and couple built ones but pretty sure I fried them because I can't get any info on the power supply that is needed. I am scrambling for some solution to a long and apparently friction heavy PTFE run and this buffer was the only one that runs independently. I have a Snapmaker Artisan and the extruder keeps lifting from pulling on the filament. If you have any advice on this buffer or another solution I would be forever grateful. 

[mvdveer]

4 hours ago, TonyN said:

I can't get any info on the power supply that is needed.

Here is the pinout of the board. I get my 24V power from the powersupply in the Voron (Meanwell LRS200). But you can use any 12V-24V powersource. Power in is on the main switch, the first two pins.

Here is the link to the documentation that shows the connection: (In this configuration the LLL Plus operates as a buffer only, no runout or other functions.

[goofballtech]

6 hours ago, mvdveer said:

Here is the pinout of the board. I get my 24V power from the powersupply in the Voron (Meanwell LRS200). But you can use any 12V-24V powersource. Power in is on the main switch, the first two pins.

Are you running with the stock firmware or have you flashed klipper?

[Penatr8tor]

1 hour ago, goofballtech said:

Are you running with the stock firmware or have you flashed klipper?

I'm running the latest firmware from Mellow. You just need to download and flash per the instructions. Once you've done it once, you can very quickly update all of your buffers. 

There's two ways to configure, one which is auto mode with klipper macros and filament run out detection and the other is straight buffer mode where you only flash an hook up power.

@mvdveer and I are using the buffer only mode as we have other devices already installed to detect filament run out.

The way buffer only mode works is that when the filament passes thru the rollers and triggers the switch, the buffer will run the motor, advancing the filament until resistance is felt and the buffer tube rises until it triggers a sensor and stops.

The way buffering works is as follows. As you printer pulls in filament the buffer tube lowers until it hits a sensor. That event triggers the stepper motor which make the buffer tube rise until the tab on the tube hits the upper sensor. As long as filament is being pulled into the extruder the buffer will continuously be filled.

The advance buttons move the filament forward or reverse. I believe single press starts and stops filament advance, the reverse button needs to be held to fully remove the filament. 

[goofballtech]

Interesting. I flashed klipper on them to play with and am essentially recreating very close to the same behavior with the additional ability of the head filament sensor sensing unload happened and auto retracting the filament back to the buffer similar to a typical AMS style behavior. I am trying to use them to feed each head of a stealth burner but perhaps the unload feature isnt worth the additional effort. I'm pretty close now though, just tyring to get the async smooth when running higher speed prints. 

[Penatr8tor]

I'm curious to see what you come up with. Post your results when you get something useable please.

[mvdveer]

5 hours ago, goofballtech said:

Are you running with the stock firmware or have you flashed klipper?

Yes, stock firmware - Version 1.1.5

[PFarm]

@mvdveer @Penatr8tor Sanity check "buffer only", only 12/24 needs to be wired, nothing else? Do I need to change any of the default parameters?

[Penatr8tor]

48 minutes ago, PFarm said:

@mvdveer @Penatr8tor Sanity check using in "buffer only", only 12/24 needs to be wired? Do I need to change any of the default parameters?

Yup, just 24v power. You can bench test it easy on your rig. No need to change anything just flash the latest firmware. You can attach the sensor wires later and control filament detection with macros they supply.

I'm not doing that because my arbiter filament sensor already does that and all I need is positive pressure on the filament to reduce the pulling burden on the extruder.

You might want that functionality. Just know it can be added later.

[PFarm]

@Penatr8tor Thanks for the reply, I don't need filament detection, like you Orbiter Filament Sensor looks after that. I ran some Nylon-CF, which is much stiffer then other filaments, causing more drag on the PTFE tube and causing the sensor LED to flicker from green to yellow. Hoping the buffer will eliminate that. 

[PFarm]

@mvdveer Thank you for the awesome assembly guide tested my buffer this morning had to slightly enlarge the hole the filament passes through on the PTFE guide. It works flawlessly