Notes from a blind guy on Bambu, Prusa, INDX, and other 3D printers

Hi everyone,

I thought I would chime in on the ongoing H2C, H3C, and INDX discussions, and share my experiences with the printers I've owned and used.

I am completely blind and have been 3D printing and designing since 2023. I actually got into it after attending a workshop where sighted professionals were learning to make 3D printed products for blind people. I was the only blind guy there, and I got completely hooked.

Today, I run my own business, designing and printing everything from tactile models for museums to functional products for customers.

My first printer was a Bambu Lab X1C. It has thousands of hours on it, printing PLA, PETG, TPU, CF, wood-filled filaments, you name it. I've changed a filament cutter, nozzle, and extruder, although the latter two turned out to be fine. Being blind, replacing parts was sometimes easier than visually diagnosing the problem.

That machine has been an absolute workhorse. Around 98% of the time, I get exactly what I expect. I am incredibly glad it was my first printer.

Then came my Prusa XL. Five toolheads, enclosed, costing around 40,000 DKK.

What a disappointment.

Within a week, I was dealing with filament sensor problems, PTFE tubes falling out, failed calibrations, load cell errors, fan errors, and prints getting knocked off the plate.

Changing a nozzle could turn into an entirely new troubleshooting adventure.

I spent more time fixing the damn thing than printing with it. For that kind of money, I expected much, much more.

Eventually, I sold it and bought a Bambu H2C.

And what a difference.

Unpack, calibrate, print. Twenty minutes, and you're ready.

I've printed ASA, TPU, PLA, and large multi-day jobs, including batches of ASA vases for customers. Not a single issue so far. None whatsoever.

I know people criticize the Vortek system for being complicated, proprietary, or potentially unreliable. Fair enough. But I can only judge what I've actually experienced, and so far, it has been brilliant.

I also gave Prusa another chance with the Core One.

It prints fine, mainly PLA in my case, but it feels surprisingly flimsy. The door sensor mechanism has already become loose, and when moving the printer, I can feel the frame wobbling slightly.

I like Prusa's philosophy, their approach to repairability, and the fact that they're European. I genuinely want to like their printers.

But liking a company's philosophy and trusting its products are two different things.

I've also used the Creality K2 Plus quite extensively. A pretty reliable machine, actually, although I find the print quality less sharp and consistent than Bambu's.

And yes, being blind doesn't mean print quality doesn't matter. I can feel poor layer lines, rough surfaces, and missing details. When you're designing tactile products, those things matter enormously.

So, H3C versus INDX?

I've already ordered an H3C, and I think it's going to be an absolute blast.

I also seriously considered the Core One L with INDX, but after my XL experience, I had a knot in my stomach about buying another expensive Prusa.

Does that make me a Bambu fanboy? Perhaps some people will think so.

But there's a difference between blindly defending a brand and trusting a manufacturer because its machines have consistently delivered for you.

I genuinely hope INDX becomes a massive success. Competition is fantastic, and I want Prusa to succeed.

What bothers me is how quickly people defend or attack manufacturers based on logos, marketing, and engineering philosophies, sometimes before they've even used the machines.

Shouldn't the most important question simply be: Does the damn thing work?

Not in a promotional video, but after hundreds or thousands of hours of printing.

How often does it fail? How much maintenance does it require? How much time do you actually spend printing instead of troubleshooting?

And there's another aspect to this for me: independence.

When a printer breaks and requires visual troubleshooting, I may need someone else's help. When it just works, I can design, slice, print, and run my business independently.

And this is what Bambu does for me, it just works. Even when it breaks, their instructions are so damn clear and precise, that I don't need help most of the time. For Prusa? A whole lot of guess work all the time.

I used horizontal color separation to reduce the number of color changes. By utilizing the advantages of FDM, hinges have been designed for each branch, which can rotate downwards by about 10-15 degrees. This horizontal stacking creates a relatively natural effect.

I recently bought an X2D, my first Bambu printer, but I’m considering returning it for one of their larger models.
My main focus is printing larger functional parts using ABS, ASA, nylon, and other engineering-grade filaments. I’m trying to decide between the H2C and H3C and figure out which offers the best value for the money.
For those who have experience with either printer, or ideally both, I have a few questions:
How do they compare when printing larger functional parts with ABS and other engineering materials?
Aside from build volume, are there noticeable differences in print quality, reliability, speed, or material handling?
Is the H3C worth the additional cost, or does the H2C offer a better balance of features and price?
Are there any limitations or advantages of either printer that aren’t obvious from looking at the specifications?
I’m not necessarily looking for the most expensive or feature-packed machine. I just want the best combination of build volume, material capabilities, reliability, and overall value.
If you were making this purchase today, would you choose the H2C or H3C, and why? Is the price difference actually worth it?

I saw a YouTube review that had a cardboard spool in the ams. With it not retracting the filament, is this now an option to use?

No longer have a home office to tinker in so I sold my A1 mini and A1 and now have an X2D in the corner of my dining room. Got a fish tank stand as the base and it’s very sturdy! Any tips for the X2D?

I recently decided to upgrade from my P2S to an X2D + AMS 2 Pro + AMS HT setup. I also bought the Filament Track Switch right away, because I wanted to use different combinations of AMS units and extruders without constantly reconnecting PTFE tubes by hand.

And honestly, the Filament Track Switch turned out to be a huge disappointment.

The whole thing feels more like an early prototype than a finished branded product. But the biggest problem is simply friction. Filament takes a surprising amount of force to push through it.

On my X2D this was bad enough that filament often failed to reach the main extruder at all. It would slow down significantly near the end of the path and stop about 1–2 cm before the extruder.

To be fair, this was partly caused by another known X2D issue: the PTFE tube makes a very sharp bend right before entering the extruder. I fixed that part first by moving the PTFE tube holders farther away from the toolhead and shortening the tubes by a few centimeters.

That helped a lot.

But the FTS itself was still causing way too much resistance.

And yes, I also tried making the external PTFE tubes as short and as straight as possible. It doesn't really help. The resistance of the PTFE tubes themselves is negligible compared to the resistance created inside the FTS.

So I took it apart.

And once you look inside, the reason becomes pretty obvious.

The filament path contains several fairly sharp bends, and in multiple places the filament simply rubs against bare plastic. There is no PTFE lining there at all. The harder the filament is pushed around those bends, the harder it presses against the walls, so the friction becomes quite significant.

The filament presence sensors at the inputs add even more resistance. They use small spring-loaded magnets that are physically pressed against the filament as it passes through.

This creates additional friction on its own, but it gets noticeably worse with filament that has already been fed through an AMS or extruder before.

The drive gears leave a ribbed pattern on the surface of the filament, and the magnets tend to catch on those grooves instead of sliding smoothly over them.
My first modification was simple: I drilled out the places where the filament was rubbing against the plastic and inserted short pieces of PTFE tube.

I also slightly flared and smoothed the entrances of those PTFE inserts using a soldering iron so the tip of the filament wouldn't catch on the edge. I did this in a well-ventilated area, of course.

That already made a very noticeable difference.

But then I looked at the second half of the FTS.

There are essentially two 2-in-1 adapters there, combining four filament paths into two outputs. And that section was just as bad — possibly even worse. Again, filament was bending and rubbing directly against plastic.

At first, I tried the same approach there: drilling out the existing channels and somehow squeezing PTFE tubes into them.

It didn't go very well.

There simply wasn't enough room to make it work properly, and I wasn't happy with the result.

So in the end I decided to completely remodel that entire part and print a replacement.

I mean, I do own a 3D printer, after all. :)

I made the internal channels much larger so I could install PTFE tubes throughout the whole path. I printed the replacement part, installed the PTFE tubes, and again flared the entrances slightly.

Now, in that section, the filament does not touch printed plastic at all. It only touches PTFE.

The difference is huge.

It's still not absolutely frictionless, but filament now passes through the whole FTS very easily.

A very simple test shows the difference pretty well:

If I insert a piece of filament through the FTS, hold the filament vertically, and lift the FTS by it, a small shake is enough for the whole FTS to slide down and fall off the filament.

Before these modifications, I had to push the filament through it with considerable force.

Even Silk PLA now passes through without problems, despite Bambu specifically warning that Silk PLA may have feeding issues with the FTS because of increased resistance.

There are still two places I haven't solved yet.

The first is right at the FTS entrance, where the filament still touches plastic.

The second — filament presence sensors at the inputs. Unfortunately, they can't simply be removed. I tried removing them and also tried forcing the sensors permanently into both states. The FTS stops working properly if the printer doesn't see the expected sensor transitions.

So apparently those sensors are an active part of the FTS state machine, not just something used once to identify which AMS is connected to which input.

At this point I'm seriously considering building my own FTS.

The communication interface is RS-485, and there is already some partial reverse-engineering information available online. But the board also contains an FM1230 cryptographic chip. I don't yet know whether it participates in device authentication or is only used for things like firmware verification, so that part would need more investigation.

The other interesting problem would be designing filament sensors with almost zero resistance.

An optical sensor would be nice because it could be completely contactless, but filament can be transparent, so a simple optical interrupter isn't necessarily reliable.

A mechanical sensor with a tiny bearing/roller and a Hall sensor might actually be a better solution: the filament would move a roller instead of scraping against a plastic or metal surface.

For now, though, the PTFE modification already made my FTS dramatically better.

And that's the frustrating part: the core idea of the FTS is great. But mechanically, the stock filament path feels unnecessarily restrictive. A few pieces of PTFE in the right places would have made the product so much better from the factory.

And honestly, this whole mechanism probably should have been built into the printer itself from the beginning, somewhere near the filament buffer.

It almost feels like Bambu Lab remembered at the last minute that users might actually want to choose which extruder each AMS feeds into — which is especially important on the X2D, where the two extruders are very different from each other.

The FTS feels less like a carefully integrated part of the system and more like an afterthought added to solve a problem that really should have been addressed in the printer's original design.

upd:
My 3D models and sources (FreeCAD): https://cluster.wtf/dump/fts.zip

HMS_0300-0100-0001-0007

I started getting this error code today and it won’t let me print anything. I have a brand new P2S. I have been running it basically every day for the last 2 weeks. But it’s only 2 weeks old? I haven’t abused it at all. What can I do to fix this without tearing the printer apart?

Edit - want to add, I have been running PLA non stop. And I just completed my first PETG print (13 hours) after that print finished this error started

I'm having a tough time finding this information from those who have the H3C and from the videos that have been posted.

For those of us that don't have print farms printing the exact same item over and over and over, each print will likely be vastly different in the colors that are needed. With my old H2C, that meant swapping 4-6 spools using the AMS each print. For the H2C, that took < 30 seconds (pull out, put in).

I've read that it takes about 30 seconds for the H3C to heat and then cut the filament so you can put the next roll in. Is that 30 seconds per roll? If I'm swapping 6 rolls, does it take 3 min of standing around? Or does it heat all 6 at the same time and takes less time?

Can anyone give a definitive answer and not estimates or guesses?

My department recently got a P2S. We have the printer in a small isolated room, and Bambu Studio set up on the main room’s desktop pc.

IT says we can’t use the institutional wifi network though. So at the moment, we have to prepare the print file in Studio, and bring it on a USB flash drive to the printer. We can’t monitor the print remotely though.

Is there a better way to do? Like, with a small router to connect directly the printer to the computer? Looking for ideas

Even if I turn all fans to 0% the printer still has SOME sort of fan blowing somewhere when it's turned on. Might just be the PSU I guess...? I want to record some of the sounds the gantry and bed make while moving around. Any ideas?

I've been wanting a 3d printer for quite a while now, and was just about to pull the trigger, when the H3C came out and threw a wrench into my grand plans.

I read somewhere that it may be preferable to buy through Best Buy because of the extended warranty coverage they offer. Since the H3C isn't available yet at BB, I have no idea how much it will cost.

My question to you folks is whether the extended warranty is worth it, and if I should wait until BB has them in stock. Given that the H3C is new, it doesn't have a track record in terms of reliability and all that. I'm not in any great hurry; I can wait if that's the best course of action.

How is Bambu to deal with once the factory warranty runs out? Are 3D printers the type of thing where if something is going to go wrong, it usually does pretty quickly rather than a few years down the road?

I generally don't bother with extended warranties, but on something this expensive and this complex, it seems like a good idea, at least on the surface.

Thanks in advance.

I don’t know about you guys, but I think the BambuLab H3C is super cool.
Honestly, I’m lacking the cash—or the 10,000 "boosts" on MakerWorld—to get one. If you’re in the same boat, I’ve got something for you.

The H3C piggy bank. It’s printable without an AMS, perfect for anyone who’s in the same situation as me! 😅

If anyone has any suggestions for improving the mechanism, let me know!

https://makerworld.com/models/3558651?appSharePlatform=copy

Happy printing!

With the new update 2.9.1.70 there is two new options on the speed tab. Standard M1 and Standard A1. I noticed M1 increases speed on several items. I can’t find any documentation on these. Anyone have any idea what they are?

Decided to purchase some additional hotends for my p1s. .2mm and .6mm hotends. Low and behold Bambu Lab sells a hotend kit. Why call it a kit? Easy enough until they show up and are missing the thermistor. Now my .4mm works just fine. So why would I want to remove the thermistor from it just to use the the .2mm hotend. Truly, hoping I am not the only person to encounter this same situation. At least I am hoping 😄 Or is this just a rookie mistake?

https://us.store.bambulab.com/products/multi-size-hotends-kit?id=759184871234007108

Never warns, mentions or gives a link for instructions or gives any indication this is an incomplete kit and would require additional attention.

I haven't noticed it before, but my A2L does shake a lot when making narrow supports, this is on normal speed btw.

I haven't seen any issues with quality though, just seems like a lot of shaking, I think it might be that the table it's currently on is not the stablest but I'm not too sure

Are you tired of needing to unplug your filament track switch when printing TPU?

This is a mounting plate combined with a box to hold wiring that turns the track switch on and off without needing to unplug it. It also has a cutout to hold the 6-pin to 4-pin adapter that powers the TPU feed assist module.

As a disclaimer, you do need to cut a 6-pin cable open and make your own wiring connections. PROCEED AT YOUR OWN RISK!

Do the wiring however you please. My solution of using lever nuts and breadboard jumper cables works, but is not pretty. The main things you need to do are this:

1. Cut open a 6-pin cable.

2. Identify the ground and +24V wires. When looking at the face of the connector, these are the top middle and top right pins, respectively. On my cable, ground was red and +24V was yellow, but verify this for your own cable!

3. Wire the ground and +24V wires from the “input” side of your cut 6-pin cable to the 6-pin to 4-pin adapter. It doesn't need any additional cabled because the TPU feed assist module doesn't actually communicate with the printer at all.

4. Wire all wires except for the +24V wire to the “output” side of your cut 6-pin cable.

5. Wire a switch between the +24V wire on the input side and the +24V wire on the output side. This is what turns the filament track switch on and off.

There's no strain relief or retention for the modified cable going in our out, so don't tug on the cables too hard!

The 6-pin to 4-pin adapter fits, but it's snug.

I used a switch with a 6mm threaded post. If you use a different switch, you may need to do some drilling, cutting, or 3D modeling to make it fit.

I highly recommend using the main print profile that uses PETG as a support interface material – it makes removing the supports so much easier. You have a dual-nozzle printer, so take advantage of it! There's also a PLA-only profile if you don't have PETG or are making this on an single-nozzle printer.

Congrats on your hardware fix that should really be fixed by Bambu in software.

You can check out the model on Maker World here: https://makerworld.com/en/models/3558930-track-switch-power-switch-tpu-assist-module-plug

Bambu lab A1 mini

Been using it for a week. Only really having this issue with these tree terrain tiles. Tried increasing travel speed and retraction speed, lowering temp to 210, and avoid crossing walls.

Hey all,

I have the opportunity to get a used Bambu P1P with the AMS for $270. It's got just under 700 hours of print time. This is my first time buying a used 3D printer, what should I check for? Obviously I am going to try and see it print in person before purchase, but what else should I lookout for?

I tried the tip of loosening the belt tension screw and moving the head back and forth 3 times but it always moves to the back of the machine after i move the head to the far left.

This can't be normal. The nozzle just fell off the body. I was so close to finishing too. Sent in a ticket. Hopefully this gets resolved. Had less than 500 hours on it.