The Fuse 1 cannot print Nylon 12 GF reliably

To branch off our in depth review topic…

We are unable to get Nylon 12 GF to successfully print on a Fuse 1.

Curling of the extra thick surface armor at the start of the print/chamber will not allow it. It’s a crap shoot if it will succeed and after 4-5 print jobs attempted in a row, in the past 48 hours…all failing…we’re not getting anywhere or closer to any true resolution from the support team.

Support is aware of this issue and are supposedly going to release a firmware update to help make this possible…but as of now I’d say it is false advertising to expect that the standard Fuse 1 can currently succeed in printing Nylon 12 GF repeatedly.

I wish this was an issue with our particular machine, that they could identify, but right now that does not appear to be the case and I think they overshot a bit in promoting Nylon 12 GF, on the standard Fuse 1.

Only thing left for us to try, possibly, is to move the parts way further up the build chamber to allow more buffer between the start of the prints (lots of wasted powder) and or try and run all “fresh” powder versus the current 50% refresh rate we are trying. Nylon 12 GF is suggested at a “spread” of 30%-50%…and wander if we could actually get successful prints again by going 100% fresh powder.

Reason I think these things might make a difference, is that with some buffer in the print chamber added at the bottom, we were getting just one to two prints to fail at the start…lowering the parts today to the bottom of the chamber in Preform (still within allowable boundary)…almost all the parts were curling and failing at the start. Also, we were able to get a few jobs to succeed more at the start of all this…so wandering if the 50% refresh rate advertised is anywhere close to being actually possible…

Neither of these things, if they make a difference, would be optimum due to the excessive waste of powder to make it all work.

We are looking to give this system another solid week in attempting to actually/consistently print Nylon 12 GF before looking at other options.

Our last resort will be to clean out the system and load regular Nylon 12 in to see if it makes a difference. However, even if it does, it is unacceptable as we were sold this machine in the confidence and need to print in Nylon 12 GF.

As of this weekend, it looks like we may be getting our hands on the new Sinterit Lisa X soon to be able to compare these two systems side by side.

Fingers crossed one of these two systems work, as I still have hopes in SLS for our production parts.

After several attempts to reset, clean and print successfully in the past few days. We are left with an unusable system out of the gate with the Fuse 1 and Nylon 12 GF.

Some good videos of what is going on (Note in this example we left over an inch of clearance under the first parts and the start of the print)


and the rest failing


After a few days of back to back failed starts with surface armor warping, seven in a row failing, we dumped the hopper of the 50% refreshed powder (8kg) and dumped in two fresh jugs of Nylon 12 GF.

Zero issues at the start of the print and it’s still printing. Night and day difference.

So now the question is…what is a doable level of reusing powder/refresh rate for Nylon 12 GF, if any?

We currently have over 12kg in 50% refreshed powder that doesn’t appear to be printable…that’s a lot of fresh powder wasted. Both of the cartridges we have are filled and the sift itself is overflowing with it. So we’re about to go purchase a large air sealed container to start dumping all that powder into to free up the sift and our cartridges.

Hesitant on wasting money on figuring out what the actual acceptable/usable mix ratio is for Nylon 12 GF, but I don’t believe it is between 30-50%. We’d have to start at 90% fresh…n work are way down to failure…

Regardless, not being able to reuse powder or even anything above 50% is going to make the return in investment for this machine in our production part attempts, all that more difficult to reach.


I am sorry to hear that you have been having trouble with the Nylon 12 GF powder; I personally am a Services agent for our SLA printers specifically and don’t have much experience troubleshooting the Fuse, but I would advise that you open a ticket with our Support Team if you haven’t already. We have a dedicated team of Fuse agents who can assist and ensure that you are well taken care of!

This is already ongoing with support but I feel an open discussion is beneficial not only to us, but others who are looking into this platform and/or dealing with issues. Support can only do so much and replace so many parts…before the platform itself and these issues are addressed.

The community may help free up support questions for others…if they are resolvable

Just an update for those browsing.

After a total dump of the Fuse 1 hopper and Sift of all 50% Nylon 12 GF refreshed powder, and replaced, out of the jug with fresh 100% Nylon 12 GF…we are back to perfect prints and no warping/failing.

So now we will be testing what a usable refresh rate actually is for Nylon 12 GF. We will start around 75% and move down as we do some more jobs to see where it starts to fail again.

Unfortunately, this really cuts into our margins on individual production parts and I definitely don’t think you can advertise success with Nylon 12 GF down to 30% and we will confirm that 50% refresh is even obtainable, as advertised.

If any actual customers are doing production runs in Nylon 12 GF and seeing different results, we’d love to hear from you!


Thank you for sharing your experience with the Fuse 1. We are currently strongly considering the purchase of a Fuse 1+ and any form of experience helps to get an idea of the machine.


If you read my other posts, I absolutely wish the sales team would have made us aware of the Fuse1+, which came out a week after we received our Fuse 1, but unfortunately they did not. Which I believe would have made this a very viable option for what we are trying to do, which is run production parts.

Since this thread, I’m currently creeping the refresh rate of Nylon 12 GF down from 100%. Last successful prints were at 80% and we’re about to get to a 70% test. This was after the machine started to consistently fail on jobs even at the higher end of what Formlabs advertised (50% fresh powder). They advertise 30%-50% of fresh powder needed… However, I don’t think that is going to happen unless it was just a bad batch of powder that contaminated the system…fingers crossed.

To meet part cost and a ROI (return on investment) we were planning on at least a 50% material refresh with high hopes of getting at least close to 40%. Running this machine 24/7. This is TBD.

It is a big difference in advertising a cost of $375 to even $225 “per chamber/print job” than the current $525 per chamber cost I am roughly getting away with at the moment. When those two small jugs of powder cost nearly $750 and you can’t even get a 50% refresh rate, it adds up and really forces you to pack that chamber tight.

This thing is absolutely awesome at printing consistent production looking parts that we then Rit Dye in Graphite (gray/black)…It runs perfectly with a good cleaning regimen, but the refresh rate issues and the fact we are stuck with the original Fuse 1…is going to make our ROI harder to ever meet.

We’d hoped to have had Nylon 11 CF available to use as well, but a sales rep misinformed us on that possibility as it is only available with the Fuse1+.

Our parts are just a tad too high cost per part…with those current refresh rate issues combined with the print time required per chamber.

If the Fuse 1+ actually has a better “zero waste” refresh rate with nitrogen and with its double the speed…we could have probably made our dreams come true, but with no “upgrade” options and being flipped the old model right before announcing the Fuse1+… we are kind of stuck with what we got.

If we did not require higher end production parts, then I’m sure this base model Fuse 1, with regular Nylon 12, would have been a great option.

All in all, SLS is definitely awesome…compared to the years of trying to do production on FDM (lots of snake oil salesmen in that market). This is a game changer. MJF would be the next big money leap.

Glad you found the posts. I know I spent months looking for a “real person/review”… and they DON’T exist. I make plenty of You Tube videos for our company…and was thinking of launching an in depth review there as well. As there is not a single “real user” video up on the Tube either…which is surprising.

Definitely pay the extra for the yearly Full support…as we needed it and they are at least great and very responsive!

Good luck with your purchase and let me know how it goes.


In fact, we have already had a live demonstration at a dealer to get a better impression of the Fuse1.
Nevertheless, it is simply experience that ultimately passes on the really useful knowledge points.
I also think that the support for such a machine is very important.
If we did, we would book the support option anyway. Still, it’s positive that this consideration is approved.

Regarding the refresh rate, I think I heard from another dealer at a trade fair that although formlabs advertises these low rates as possible, the maximum achievable mechanical properties are more likely to be achieved with these higher refresh rates.

If we buy the fuse1+, I will be happy to write or film reports of my experiences here as well.

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I would like to update those interested in the Fuse 1 system and their Nylon 12 GF after extensive testing on this issue with failed curling prints (surface armor) at their advertised 30-50% refresh rate.

After continuous failures with Nylon 12 GF on the Fuse 1 at a 50% refresh rate, we totally cleaned out the Fuse 1 and Sift of all powder and put fresh 100% Nylon 12 GF back in. As soon as we did this the system was printing 100% powder with 100% success from previously failing every single job.

We gradually worked the Sift down through the refresh rates at 90%, 80%, 70% and everything ran with no issues. We just hit 60% refresh and we are back to the same failed curling prints (surface armor).

At this point I would say it is positively false advertising for Formlabs to say that this thing can do 30-50% refresh… It cannot do 60% and a 30% would be a complete and total lie…maybe 50% if you were printing a solid block part…

This is really cutting in on what we thought this thing could do and our margins per part. It being also at a higher fresh powder ratio than sifted powder ratio… means we have to dump/perge the Sift as we go because of the build up of Sifted powder that can’t be used/wasted.

Here you can see what happens after no issues whatsoever at a 70% refresh and the first job where we bumped down to 60%…same same as all the issues we were having before.

Formlabs needs to take down their false claims of a 30-50% refresh rate on Nylon 12 GF immediately from their website and put the proper realistic specs in there so folks can do a realistic cost analysis of bringing onboard this system.

This needs to be addressed immediatly as this is false advertising on their part.

i always thought that 30% refresh rate means that the machine is using 70% new power and 30% recycled.
I got a bit confused by your 60% refresh failure. So are you using 40% new and 60% recycled?

No, the refresh rate is how much is needed to “refresh” the old unused powder. They advertise for Nylon 12 GF that you can refresh 30%-50% “NEW” powder into the old unused sifted powder.

Read this for more info

Nylon 12 GF won’t do anywhere near this as advertised.

We are finding it takes 70% NEW powder to refresh the old unused powder from previous print jobs to get successful prints.

Since the Sift is meant to recycle powder afterwards while post processing your jobs, where it stores this unused sifted powder in its hopper, this “upside down ratio” means you have to physically purge/hand scoop out and throw away unused sifted powder otherwise it’s overflowing the Sift with “wasted powder/cash” and never getting blended in with new powder at that ratio.

To put this in perspective, these jugs of material cost $710 dollars for two (6kg). A chamber of parts is about 6.59kg. In that chamber you are shooting for a 30% density but realistically we’re getting a 20%. This means that all that unused space between parts is “unused” powder that will then be sifted. We will have full chambers with parts taking up 1.5kg ($177) of printed powder and over 5kg ($590) of unused powder. (See chamber example in photo below).

What we are able to do with this material successfully, is a 70% “refresh” ratio. Which is needing you to mix in 70% of new fresh powder into this 5kg of unused sifted powder. So of that 5kg ($590) we are tossing and throwing away $413 dollars every print job or nearly one and a half jugs…of a two jug $710 order…it’s waste.

Totally unacceptable and a terrible amount of waste in material and money.

Hopefully Formlabs can get this right in a different material make up but they absolutely need to stop advertising this original Fuse 1 system and material as they are. We understand “fudging the numbers a bit” for marketing hype….but at this level it’s ridiculous.

Also notice…Nylon 12 GF is the only material they advertise at a ratio “spread”… of “30-50%”… all others they provide a definitive ratio it can do.

For example
-Nylon 12 is promoted at 30%
-Nylon 11 is promoted at 50%
-The all new Nylon 11 CF at 30%

With Nylon 12 GF, being the only material they advertise at a “spread” of…

-Nylon 12 GF is promoted as a “30-50%”…

Honestly I believe this is because they know how questionable that is and anything over 50% being unacceptable for them to advertise. As again, the Sift can’t truly function smoothly with anything over a 50% with the wasted powder build up that needs hand removed and disposed of. Not to mention the amount of waste in material and money as shown in our use.

We need to run rugged production parts and needed Nylon 12 GF or Nylon 11 CF to do so (we would have gotten the Fuse 1+ *see prior posted reviews) but this Fuse 1 system and their Nylon 12 GF is being falsely marketed in costs and materials to do so.

The printer and technology is amazing. The parts are amazing. From our experience, I’m just telling you if you are looking to print prototypes in Nylon 12 the Fuse 1 will probably be great. If you want serious rugged production parts then hopefully the Fuse 1+ can pull this off with its Nitrogen chamber capabilities in Nylon 12 GF or Nylon 11 CF…

We will never know as we were falsely sold on the standard Fuse 1 and this material, unfortunately one week prior to their announcement of the Fuse 1+

It’s a dang shame as we could have really highlighted what this thing could do in our use case but we may never know.

Interested to see how the new Fuse 1+ system handles this material from any real people out there… staying tuned.


I have been following you tread. We are actually on the marked for the Fuse 1, and we will probably be using the PA12 GF.
Do you have any news? Is it up and running with a decent amount of refresh powder?

I’m blasting production parts as we speak and the parts it produces are amazing…

However, I am still waiting on Formlabs to to come up with anything as this machine will only print Nylon 12 GF for me with a 70% refresh rate. (advertised with 30-50%) So I am throwing away about $400 worth of powder every $700 chamber job.

Literally scooping out and “throwing away money”, because the ratio is “flipped”. I have a stock pile of used sifted powder that will never get reused with that ratio…

Even for Nylon 12 GF I would have preferred to have splurged on the Fuse 1+ for its additional speed and because I believe the nitrogen filled chamber would have gotten that refresh rate down. Both time and material would have probably made this worthwhile.

I have yet to talk to another real person printing production parts with Nylon 12 GF, even though supposedly the recent “out of stock” of Nylon 12 GF is because a single company just bought up all the available material… I would absolutely love to talk to this company to see how their refresh rates are going! (you out there…?)

Support passed me to their engineers who are supposed to give me a Beta software update to try to stop/test the surface armor curling I’m seeing under 70% (fresh)… but its coming up on a week with no information on that yet.

Definitely pay the yearly full support… as I had my first Sift turn out to be a lemon, a faulty chamber I am waiting for replacement on (I ordered two). The other $3500 chamber has been sitting here for nearly two months collecting dust with its significant Z shifts. They wanted me to tear it apart and retighten everything…but I’ve been busy and honestly not sure why I’d need to do all that with a brand new chamber out of the gate. I’m all about maintaining things as you go but it should work perfectly out of the box.

They’ve given me plenty of free powder to troubleshoot all this as again support at least has been great.

As far as the capability again, it is amazing… you just have to calc the cost of the above but for me having the need to run this system 24/7 for my production parts, I believe the Fuse 1+, even though its double the cost with Nitrogen system etc… would have been more profitable in its speed and hopefully in the fact it can print even anywhere close to the Fuse 1’s advertised 30-50% with Nylon 12 GF…

Good luck and let me know how it goes with this material! Would be great to hear from someone else actually using Nylon 12 GF…as I feel like I am alone on a remote island… Ha

@LEADNAV I’ve had several ongoing major issues with my Form 3L’s that stretch back as far as the first day I got them over 2 years ago. As with any of their new products, you as the customer are the guinea pig and help them develop their products. They overpromise and under deliver.

I have read your other threads about the Fuse 1 and you indicated that you had looked at the Lisa X. Knowing what you know now, would you have purchased the Lisa X instead? Any other machine for SLS that you’d be looking at?

We’re about ready to dump our fleet of 3L’s and move onto something else and likely trending towards SLS.

Answered this in the outside post you tagged me in but I will put it again here for anyone else reading this.

The system itself has been running amazing parts and the Formlabs support team has been outstanding. I am however, definitely frustrated with the waste and cost of material over what they promised. After a few months of troubleshooting we finally found out it was really a case of the printer not being able to print anywhere near the advertised material refresh rate. There were a few other “lemons” in hardware but they replaced those components.

In my year long search for “production run” capabilities… “SLS” and MJF are the only true options out there…period.

After a year of trying, there is no true way to run “professional parts” (instead of toys) on any FDM printer and as far as Resin…it makes great detailed models and prototypes but there is no way I’d deal with the post processing and mess involved with that in any production run environment. It also does not have the strength or temperature resistance that we needed. There are definetly uses for it though…just not in our product line up.

With SLS, there is literally no real post processing pains and the system we have for blasting and dying, leaves us with flawless, identical, rugged parts.

Can’t express enough how happy we are with the SLS decision and the Fuse 1 has been doing outstanding running our production parts…

However, I do think Formlabs need to be a bit more transparent on the true expectations of these machines and materials, and adjust.

They did launch an update/beta but I am hesitant to bump down to 50% refresh…after everything we been through…as I got parts to run and don’t want to kill an entire hopper of working powder to try it.

After lots of headache of trying to dial this thing in at their “highest recommended refresh rate”… we found out that the machine just cannot successfully print within the advertised “30-50%” range. We are running successfully now at 70% refresh and starting to push that down to 60%.

Again, support has been great at helping me but like all corporate companies…there is obviously a breakdown between the support teams and what the engineers are passing down.

The Sinterit LISA X looks interesting but it is not yet readily available. It could be great as I am waiting for my buddies out west at Vision Miner to finally even get their hands on one but they are still waiting. If it does have issues though, I’d be hesitant on the fact they are outside the US with a language barrier, so I’d definitely get it through someone here in the US to offer support.

Anyone looking at rugged production runs… GO SLS!! But I would have preferred the upgraded Fuse 1+ and/or the cost of material has to come down to make up for the unrealistic expectations they are putting out when considering your cost per part and market.

If you want to drool over some parts here ya go. For these, I am running a hundred units in roughly 30 hours consistently, 70% refresh rate, with about 2 hours of labor blasting them off and dying them in our heated tank. They look identically perfect…

“Hole Punch”/Flat head screw driver sheath in Nylon 12 GF. You can’t break it…we tried…

Any chance that FL would upgrade you to the Fuse 1+ at modest cost?

Hi all,

Thank you for sharing your feedback and experience. I certainly recognize the need for transparency in terms of expected results with the units. I don’t know specifically of any upgrade options, but our Sales team would be best equipped to address this.

Just an update

Formlabs Support gave me a custom Beta (3.27.1-BetaLeadNav_GF) that I have since ran a handful of chambers through and immediately ALL problems were solved while I gradually bumped my refresh rates down from 70% to 50% in Nylon 12 GF. Ran back to back jobs at 50% refresh with perfect prints and zero “lifting/curling” of the surface armor. Night and Day difference.

It appears in this custom Beta they refined the way and distance the surface armor projects off the different edges of the part. Giving it “less to curl” would be my guess but I have had zero issues running this beta now down to 50% refresh as advertised.

I have not tried any larger parts and my only concern, not tested, is the added warping we may get with less surface armor…

Through this process I was made aware to try and “bump up the Calibration of the chamber temp”…which I had no idea you could even do but it appears you can bump it up in increments to +5c in the printer settings.

HOWEVER… on the same email chain I was getting conflicting information on if the printers chamber calibration setting actually did anything at all. Regardless I set it to +3c for all the tests on the custom Beta.

I bring all this up as an update…but also a forewarning…as they launched this week both a Fuse and a PreForm firmware update at the same time.

I hit up support and ask them about it and if I should update because I’m still running this custom Nylon 12 GF Beta they gave me…with it finally working successfully down at 50% refresh? I thought maybe they made my Beta I’ve been running public in this new release…but I guess they did not… Not sure why, as I am confident no one out there can run successfully with Nylon 12 GF down at the advertised 50% range. If I am wrong…please speak up out there…

Anyway, they said I should be good to update the Fuse 1 printer itself and keep running my Preform custom Beta.

When I did update the Fuse 1, I saw some new changes popup in the UI on the screen. One of those was telling me that any chamber temp calibration I had set prior would be zeroed out and I’d need to retune it again. I asked support again if the chamber calibration was in fact working before this and in the same email thread I had multiple support members telling me different answers.

So I bumped the calibration back to +3c and ran half a chamber of my parts…

Well…all the parts are toast. There goes $300… Not sure what this Fuse 1 firmware did but the tolerances of the parts went all out of whack. The parts were not detailed at all as before. Some parts were cracked like a hotdog left too long on the grill…and I noticed the surface armor was harder to get out and remove.

I imaging half the support team was right in that the chamber temp calibration was broken before this update and now that it works the +3 was too much… (which I find it hard to believe that just a +3c would do that much damage but…)

I am running another test row at a default “0” chamber temp offset with this new Fuse 1 update and crossing my fingers…will let you know tomorrow.

  • Only thing I know, is that the custom Nylon 12 GF beta they gave me to run, absolutely fixed all the surface armor curling I’ve seen since day 1 while trying to run at the high end of their 50% refresh rate. (This being on my smaller parts/100 per chamber…warping in larger parts is still TBD with this custom Beta…)

  • No idea why they have not made what I’m running public yet…?

  • Tip… once you get everything working…never update the firmware…I’m already prepping to go back to the last release

If its not broke…don’t fix it /or once they fix it…don’t break it!

Side note, after the failed chamber that appeared to be printing fine, was complete, I did get an error message that I’ve never seen before while it tried to print the label.

Again… I am still looking for friends out there that are actually running the Fuse 1 with Nylon 12 GF…would love to hear that I am not alone…

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The articles about the PA12GF are great to get an insight into working with the printer and with Formlabs.
In fact, we have now put the project of a Fuse1+ into action. Our printer was delivered yesterday. We are currently doing some setup work to have a dedicated SLS workspace and will be performing the installation in about 5 days.
Unfortunately, we have planned to test the normal PA12 for our applications for the time being, as test prints made in advance at Formlabs have looked quite promising.
However, since PA12 and PA12GF can be changed relatively easily according to Formlabs due to the same polymer base, I definitely plan to try this out in the future.
As soon as we have made our own first experiences here, we can also exchange ideas in a more direct way.
Greetings from Germany