I update, revise and improve my design for my fixes very often. Please only use my Print Profile (Labelled as Designer or SPStudio) to ensure this fix is updated & work well. Profile with Non-Designer tags may be of poor functionality or non updated model.

Click on Like if this model helped you in some way. It is very important and will help increase the exposure of this design to more people who might need it. Cheers!

This is an experimental fix, although it have been tested more than 15k times in total, effectiveness will varies. Please use new V1 version of this fix if this V2 didn't work for you.

I do advise you try all my other Ams fixes, if those still doesn't solve your problem then you can try out this fix as an last resort. Most people got their problem solved even before requiring this fix. You can easily find the rest of my Ams fixes by clicking on my Profile then go to the Collection tab.

Announcement
New and Improved V2 Versions for the Ams Buffer Fix Before Buffer and After Buffer have just been released. Do check them out in my profile to see what are the improvement. Thank you for your continuous support.

Introduction

Failed to pull back filament error can be caused by multiple different variables & factors. This is a part of an series of Ams fixes that i have designed which can complement each other when used together. I do suggest you install all my fixes together for the 0ptimal effect to help your filament travel properly across the entire system which in turn can help improve, reduce or remove any potential Ams errors.

I have grouped all fixes into their respective Collection for ease of searching what to install.

V2 Collection are improvements done on the shortcoming of V1 Collection. Feel free to try V2 Collection and if it doesn't work properly then you can try the V1 Collection. You can easily find each of the Collection by clicking on the Collections tab on my profile.

Unfortunately there isn't a single fix that can 100% work for everyone. What works for others, may not work for you but my fixes is definately a great place to start and have worked for majority of the users. My fixes are precisely measured then modelled. A Proper Fix would have the highest chance to reduce or solve the error.

If you are too bored to read the entire lengthy write up explaining the need for this fix, here is the TL:DR.

What is this?
V2 Extruder Ams Filament Pull Back Fix will correct and maintain a nearly 100% straight line to move the filament in and out of the extruder. This will also reducing wear on the Ptfe tube. Its design allow the filament to travel in the most smooth, least amount of friction and pressure for the proper angle to go into and exit the extruder thus greatly reducing the possibility of an Failed To Retract Filament error or similar errors from popping up.

Who needs this fix?
I believe that anyone With or Without a Ams or even a modded Hydra Ams would benefit from this fix / enhancement regardless of do you have any problem or errors with the Ams / Printer or you do side or back spool loading.

Main difference with the previous model Extruder Ams Filament Pull Back Fix

Completely New Internal Design. This new internal design should properly aligned the Ptfe tube to the print head ending position when move to retract or extend the filament into the extruder.
Using the same installation method as V1 but with a robust build body to last longer with prolong usage.
Maintained precise measurement for reduced friction of filament moving through
Single version for all Bambu Printer Setup, regardless with riser or with stock glass positioned on tp of frame.
Can be used together with the new Rear Stabalizer which greatly complement each other.

Why use this fix?

ez to print
Dimensionally accurate to allow the Ptfe to be straight at the extruder part
Tested and measured to get the most optimal height and size to be fitted on the extruder plate yet light enough to prevents any problems that might negatively affect the movement of the Print Head.
Well Supported as its designed to be fixed with the original screws, not free floating thus removing any possibility of the Ptfe tube misaligning during movement.
Compatible with all Bambu Printers
Compatible with riser or non riser users
Unlike the common similar fixes, this fix is designed to avoid rotating with the Ptfe tube changing directions when the print head moves, when there is movement and rotation then chances of misalignment may follows. This fix is fixated on the print head itself, no matter how the Ptfe tube move it will not affected the alignment of the inwards angle of the Ptfe tube so it stays straight.

This can and will allow the filament go into and exit the extruder with a smooth movement with the least amount of friction.

Warning: V2 requires a lot mre attention to details.

Every part of the instructions below is very important to sure the fix worked properly. Please follow it strictly as it is replicating the exact machine setup details that i have done in the nearly 20k retraction tests. If you fail to do so, the fix may not work properly.

Pre-installation

Step 1 : Check the Ptfe tube inside the machine, it should not have any sharp bend or any part of the tube being squashed or misshaped in anyway. It should be also of the Bambu Specification of I/D of 2.5mm, that should have came with the printer.

Step 2 : Disconnect the Ptfe that is inside the printer enclosure. Measure and Cut the Ptfe tube, i am unsure how long is the original Ptfe that came with the machine but what we need here is Exactly 52.2cm + - 0.20mm Max.

Step 3: Move the Ptfe restrictor piece to this position. Take special note of the orientation and and its position according to measurement on the ruler. Observe the blue clip. Please do not install it the opposite way. This is a Key part please ensure and double confirm.

The rear of the restriction to be at 10.2Cm and the front of the restrictor to be at 11.1Cm

Ok the hard part is over. Read on for installation video. There are 2 part for the installation, please watch both video carefully.

Installation Video - Part 1 The Extruder Fix

Set the fix in place lightly first then align and adjust it to sit in the groove at the back plate. Notice how the fix just resting on tp of the Ptfe connector. Then slowly screw back the screws in a left right rotation motion till you feel some tension then stop.

The fix must not move up and down freely.

The screw might be tight but Do not jam in the screws all the way or screw it in too tightly. Its unnecessary. V2 requires the screw to be mre tighten fully compared to V1. Please take note.

There MUST be a very small gap in between the fix and the Ptfe Connector Head.

Do not press the fix down pressing the Ptfe Connector Head down then screw in. Please do not do that.

Just lightly rest the fix on tp of the Ptfe Connector Head , there are groove behind the fix that will match the rear plate, just sit it in and screw in lightly left right rotation, That's all.

Important Key Point

There should be 1 or 2 Ptfe Clip in the 2 circled area, Do not use excessive amount of clips to tie down the Ptfe to the cable chain. If you don't have the cable chain then leave the cable dangling.

The green circled part must not have any Clips or Restriction and should be left like this. Please do not place any clip anywhere in or near the green circled area.

Installation Video - Part 2 The Rear Guide

Get the rear stabilizer here https://makerworld.com/en/models/105334

This is how it should look like if fitted correctly. There will be enough length at the exit for you to slot in a The Smooth 4 Way Splitter or the original Ptfe connector.

Important Notes:

Note 1: This is compatible with any P1P P1S X1C with or without Ams.
Note 2: Please follow the instructional video carefully its very important.
Note 3: Hydra or Non Modified Ams can all benefit from this fix.

Note 4: Please do NOT overtighten the screws. Just tight.

Note 5: Align the fix then lightly screw in one screw follow by the next then slowly screw both screws in bit by bit turn by turn. Do not screw in either side fully then the other side fully. This is WRONG.

Note 6: You need to ensure there is a gap between the fix and the Extruder Head. Its a must. Scroll down for mre details

Note 7: Do ensure the Ptfe is inserted all the way into the extruder after you installed the fix.

Note 8: Please check and follow installation video below.

What Mod / Fixes / Enhancement do i offer?

Please don't download the wrong one. Only those in the photos below is designed by me who painstakingly took a lot of time to measure carefully and design just to get it working. #SupportOriginal Love you guys for all the support so far!

- Ams FIX Failed To Retract Filament Error (a preventive measure and solve the bay 2 and 3 error and prevent bay 1 and 4 to have any possibility of having an error due to tension and friction) (Updated design on the 2nd photo below, try 1 then if it doesn't works properly for you then install the other one.)

(BRAND NEW) Ams Filament Pull Back Fix V2 Upgraded - Completely New Design Upgrade For Ams Filament Pull Back ERROR! Precisely Measured

- Ams Buffer Fix For Failed To Pull Back Filament Error (reduce wear on the external Ptfe tube and allow the most smooth, least friction angle to go into the Ams buffer thus reducing the possibility of an error popping up)

- V2 Ams Buffer Fix For Failed To Pull Back Filament Error (reduce wear on the external Ptfe tube and allow the most smooth, least friction angle to go into the Ams buffer thus reducing the possibility of an error popping up)

- Ams Fix - Stack the Ams on tp (Using a carefully measured holder to hold the Ptfe in a curved angle that will allow filament to go through with the least possible amount of friction when the Ams is stacked on tp of the printer)

- Ams Buffer Ptfe Right Guide Mount Fix will correct and maintain a nearly 100% straight line when the Ptfe tube exit the Ams buffer to move into the printer extruder.

- V2 Ams Buffer Right Ptfe Guide Mount - The Fix For Failed To Pull Back Filament a newly improved fix designed to replaced the V1 This will correct and maintain a nearly 100% straight line when the Ptfe tube exit the Ams buffer to move into the printer extruder. ez Installation. No screws needed!

- Extruder Ams Filament Pull Back Fix will correct and maintain a nearly 100% straight line to move the filament in and out of the extruder. This will also reducing wear on the Ptfe tube. Its design allow the filament to travel in the most smooth, least amount of friction and pressure for the proper angle to go into and exit the extruder thus greatly reducing the possibility of an Failed To Retract Filament error or similar errors from popping up.

- V2 Extruder Ams Filament Pull Back Fix will correct and maintain a nearly 100% straight line to move the filament in and out of the extruder. This will also reducing wear on the Ptfe tube. Its design allow the filament to travel in the most smooth, least amount of friction and pressure for the proper angle to go into and exit the extruder thus greatly reducing the possibility of an Failed To Retract Filament error or similar errors from popping up.

- The Smooth 4 Way Splitter. Look No Further. Combined with Ams Hub Lite together with this small attachment, you will have the Smooth 4 Way Splitter.

Technical Write Up

Friction - The cause of most of the Ams filament failed to retract problem.

As shown in the following photo, the Ptfe tube that go into the extruder may and is often bent in an angle. It creates bends or pressure on the shape of the Ptfe tube in turn creates a lot of friction, as the Printer and Ams is equipped with multiple sensors, these friction will cause filament not passing through the Ams to the printer smoothly and thus causing the Ams Failed To Retract Filament Error and similarly related errors.

So what is the possible solution to the problem?
Firstly we need to reduce friction for filament passing through Ptfe tubes? Simple! If we optimise the angle of the Ptfe it will allow the filament to enter and exit the Extruder with the least amount of friction and pressure.

So what i have created to solve the problem?
I have made a fix that will extend and hold the Ptfe in place at the extruder for a proper exit angle when filament is push or pull out of the extruder.

What do i need in additional to installing this printed fix part?
Nothing, just remove the screws from the extruder plate and install the new upgraded fix that's all. See the installation video for info.

Removal Video:

Loosen the 2 screws just enough for the fix to wobble then press down and release the Ptfe tube the remove the fix.

Additional Notes

The error itself is complicated and non definitive. Whatever cause the error today might not be the same area that cause the error again, same with person A and Person B setup, as the error itself is mainly due to tension with friction triggering the sensors in the machine.

I would suggest you download and try and install all my fixes together for the proper effect as together they will ensure a smooth delivery of the filament with much lesser friction (read write ups) and hopefully that will help and reduce or resolve the error. If you use only one or 2 of the fixes the error could still happen as there are still other area might still be causing excessive friction.

Bambu P1S ajustments