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I've been designing and printing a model for the H2C Vortek contest to put it to the test. While the vortek system works flawlessly even with 10K+ cumulative filament changes, the AMS and the PTFE tubes are experiencing significant wear while printing with Matte PLA and I want to share my experience and recommendations. Do note that I bet with normal PLA, the wear won't be as significant but I haven't put it to the test yet, this post is my results on the slightly more abrasive matte PLA with thousands of filament swaps. Some things to go over first: - The H2C combo comes with bambu labs new version of their 4-In-1 PTFE Adapter II which comes with cleaning pads which is supposed to help clean the filament before it enters. These cleaning pads are easily swap-able and are inserted into slots that are open to the air. There is currently no recommendations on when this cleaning pad should be checked on the wiki as of 12/21/25, I have some at the end of this post. - When the H2C performs a filament swap with an induction nozzle, it retracts with the AMS fully and loads the new filament fully similar process to any filament swap so the AMS and it's PTFE tubes still go through a fully filament swap cycle even though purging is reduced significantly. - My design for the Starry Night Vase has about 2.7K filament swaps for the small size, 4k swaps for the medium size, and 6.8k swaps for the large size, which is halfway done. In total, my H2C has performed 10k swaps over a period of 6 days of continuous printing these 2.5 items. Do note that my design is really rough on filament swaps. A lot of times a swap will happen and very little filament will be extruded before it retracts and swaps to a different filament. More on that later. IF you do not maintain the cleaning pads in the 4-In-1 PTFE Adapter II adequately or have no cleaning at all then you will start to see problems. The first few thousands filament swaps, everything seems fine, but then by the 3-4 thousand filament swap with matte PLA, you start seeing signs of significant buildup of microplastics likely from the matte PLA wearing out the PTFE tubes and vice versa. - The first sign is you start seeing is that the new 4-in-1 PTFE adapter II will have microplastics spread out around the area where the openings are, this is the microplastics building up on the wiper and having no where to go afterwards other than out. This starts happening at around 2-3 thousand filament swaps and beyond with matte PLA. - The 2nd sign is that when build up starts being dragged around all your PTFE tubes and into other spaces. Because the AMS does a full retraction as normal during any filament changes, a significant amount of filament (depending on how long your PTFE tubes are to your printer) will be retracted back into the AMS. This likely happens because the wiper has done all it can and the build up starts to stay on your filament. You will start to see the same microplastic build up on the inside of your AMS and your filament when wound back up. This starts to happen by the 3-4 thousand filament swap if you have done no maintenance on the wiper on the 4-in-1 PTFE adapter II. It is very likely that without occasional cleaning or replacement of the wiper on the PTFE adapter II, the microplastics will start to spread everywhere. I haven't been able to investigate because my printer is still printing, but I would expect it to be in the AMS hub and the printer head gears. I have been reading reports from other people that they have printed thousands of hours with matte PLA without much issue on other machines, why is my example showing so much more wear than what they are seeing? A valid question, and I believe that the issue is multifaceted and also depends on what you are printing: There is a difference between hours of printing and number of filament swaps. When printing, your filament is advancing slowly and steadily through PTFE tubes as your extruder prints. When your AMS loads or unloads filament to swap colors, it is doing it almost full speed. You can easily imagine that fast and hard feeding and retraction will have significantly higher impact than slow and steady extrusion. The impact to PTFE tubes are best recorded by the toughest metric which will be filament changes. Not all filament changes are equal. Why you may ask especially when the AMS does the exact same routine to do a filament swap. It comes to what you are printing and what happens in between filament swaps. If your printer is extruding a lot of plastic before it even does a filament swap then it will likely be a lower impact on your PTFE tubes. This is because the extruder will flush out more impurities as more filament is used. My design often features 7 colors on one layer so it is the hardest situation where a lot of times very little filament is extruded before a new filament swap routine is started again. This means that the same filament that has traveled through the PTFE tubes to the extruder has been retracted back through the PTFE tubes again and then it will repeat this process over and over extruding only tiny bits at a time. What happens is that as the filament rubs against PTFE tubes, it will shave off plastic from the PTFE tubes and the filament itself. Because not a significant amount of filament is extruded and cleared before retraction, the microplastics will build up on the filament if not cleared. This is what you see in my situation in my photos above. When the microplastics build up on the filament, it likely makes the filament even more abrasive causing a compounding issue and causing more wear on your PTFE tubes. If you consider your filament like sand paper to your PTFE tubes, then these microplastics that build up is essentially you reducing the grit on your sand paper to sand even more. The less grit, the more aggressive the sanding is. This is why it is important to constantly check and clear out the cleaning pad of the 4-in-1 PTFE adapter II or whatever method you use to ensure there is no significant build up. I highly recommend the following based on my experience with printing matte PLA and 10K plus filament swaps as well with my discussion with all of you lovely folks who were willing to share their experience. - Inspect, clean or replace the wiper of the 4-in-1 PTFE adapter II every 2k filament swaps or less. Adjust the frequency depending on how much build up you see on the cleaning pad. More often is better. If you have long prints, you can just take it out and replace it in between filament swaps, its very easy to do. If you don't have the newer 4-in-1 PTFE adapter II with the cleaner, consider investing in one or looking for the various methods of cleaning filament methods that people have shared online. The ones online will likely have more capacity. See the wiki for info about the 4-in-1 PTFE adapter pads on how to replace them: https://wiki.bambulab.com/en/h2c/maintenance/replace-4in1-ptfe-adapter-filament-cleaning-pad - Inspect your PTFE tubes every 4-5K filament swaps with matte PLA. Replace as necessary. Reduce this number to 3kish or less if you know one particular color is swapping filaments significantly more than other colors. - If you see microplastics invading your AMS, make sure to clean and blow it out paying special attention to the mechanical feeders because that stuff sticks on everything, but avoid as possible by maintaining your filament wiper in recommendation number 1 because by this point, that means those little plastic shavings are everywhere. Highly recommend doing this in a very ventilated environment with a computer duster or electrical blower with a mask on. Don't want that stuff anywhere inside you. Remember! this is the ultra high end of prints that perform filament swaps, I highly doubt the normal person will ever experience this high amount of matte PLA filament swaps within a week as my design has but I think it is worth sharing. It is very likely that non-abrasive basic PLA will be better. Obviously my test prints print one at a time, as always it is significantly better to print multiples of the same object if you can. Keep that expectation in mind in any discussion. Here is my model if you are interested in wearing out your AMS. https://makerworld.com/en/models/2129520-starry-night-vase#profileId-2305896 Here is a picture of the waste for a medium sized Starry Night Vase I forgot to add to the album. It is really just the prime tower and a handful of actual poop: https://imgur.com/a/ue7rUin #MadeWithH2C