FLSUN V400 Delta

So my new V400 is quite remarkable. I am very happy with it. The speed pad and Klipper are awesome, I am getting used to it now. Input shaping works great. My only issues are the total lack of profiles. There are some on various sites but I am not super pleased and have been tuning settings for days now.

Does anyone use one of these monsters and have settings they like?

I have prusaslicer settings for 0.2. I am happy with if anyone wants mine I am happy to share just ask.

It might help to let us know which ones you have already tried? And what exactly are you unhappy with in the prints, this could help to get you a proper profile or fix your current one!


I have tried the stock cure version. I tried the Prusaslicer by Art3Design Printables

I took their profile and started changing it. I have ended up changing a fair bit of their settings. The top surface is a bit rough. I am trying not to compromise speed too much. The printer prints a great bench in 22min stock profile. mine runs it in 36min
Image 7120 is the bottom.


Have you ensured that the extruder is properly tuned? You may want to look into Klipper extruder calibration (great tutorial linked below). It may be helpful as well to dial in your flow rate, my slicer of choice Superslicer has these functionalities built in but I know that you can still achieve this on Prusaslicer, it may just take some more tweaking.

I also notice that there are some gaps around the walls of your print. This could be caused by many things but I wonder if you may need to bump the temperature up slightly. If you are printing fast you may need to bump the temperature up to allow for the proper flow rate. I would try the other 2 suggestions I mentioned up top before trying this one however, it is possible that after fixing those this issue could also be remedied!

Are there any imperfections on the wall of the print or are those fine?


How to Fix Gaps Between Wall & Infill (Wall Separation) – 3D Printerly.

Thank you @Matthew .

That was an old test the gaps were from using the Arcane perimeter generator, gone completely with classic. I hope they sort that out in the full release, I’m using the alpha 5 release. I have calibrated the extruder, esteps and multiplier. The dimensions were so close to perfect so the calibration is unlikely. The manufacturers pre sliced also show the same issue, cure and prusa slicers too.

The walls are as close to perfect as I have ever seen. My first printer I had in 2016, so that is a lot of prints, we have 20 Pursa’s at work and the walls are better than them all the same speed.

I think that is the real issue, The prints are blazing fast. (the shamrock with similar setting on the MK3s+ is over an hour compared with 15 mins.) The walls are perfect? So few imperfections its hard to say anything but the tops are ugly. It’s so disappointing.

I am hoping to tune settings to keep the speed (mostly) and get better surfaces. I use printers service then but don’t really tinker too much. I have a lot of experience in some areas but very little in others. I hope that there is something I am missing.

Stupidly I am testing with a filament I dislike and don’t print with. Not taking my own advice, I am switching to one I have used a lot. I plan to test higher temps in case the extruder isn’t quite keeping up. It is going very fast.

Any other notions?

Hi there, thank you for your response!

My first suggestion would be to just switch back to the stable release of PrusaSlicer. It may not show any improvement but it just helps to cut out any potential variables in troubleshooting. Another thing you may want to try is to change the amount of top and bottom layers, this could help to smooth out any inconsistencies in the final print. I would first try adding more and then try subtracting if that doesn’t help.

One more setting you could try would be to enable ironing. Or subsequently remove it if it is already enabled. This may help to smooth out some inconsistencies in the top layer, in my opinion it makes the top layer look much nicer too! I have included a guide down below for how to enable ironing.

Hopefully this helps,

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So I have a solution to my issue. The V400 prints seriously faster than every other printer I have seen Revelling the Bambus. It is a product of speed, I think. But not wishing to slow the printer but in need of better top layers (better not perfect) I have an interesting solution.

Ironing. Normally ironing speed is 15mm/s very slow and adds a serious amount of time. The V400 is easily 4x faster than most so I tried ironing at 60mm/s much better,

I kept tinkering and I am ironing all top surfaces at 120mm/s it isn’t perfect and smooth but it is only adding 4 mins over 30. so acceptable. I am still tinkering but once I get a few variants dialled in I’ll publish them and post a link in case anyone else needs them.

HAHA great minds. Your reply came in as I was writing.

Wow, how about that eh?

Glad you figured it out! If you could post what setting you find work the best when your done that would be great!


I plan too, I will dial in a 0.2 maybe a .3 draft no ironing speed setting and a .15 quality.
For comparison the right side chip cube is the stock settings. It is slower but not substantial the high speed ironing adds 3 mins to the cube. 10 min cube.

Looks great! That was definitely the solution, 10 minutes for the cube is still nothing to scoff at. I remember when I way waiting for up to an hour to have one of those printed.

Happy printing!

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the latest version of CURA has a profile for the FLSUN V400 (delta)

i bought my V400 direct from FLSUN, ( and they paid the import fees , here in thailand);
the unit came with a 4 GB(!) thumb/flash drive; it had a version of cura executable on it ;was version 5.0;
here are the instructions in the Read.me:
"1. Place the “flsun_v400 folder” in the “share\cura\resources\quality” directory under the cura5.0 installation path.

  1. Place the “flsun_v400.def.json” file to “share\cura\resources\definitions” directory in the installation path.

  2. Place the “flsun_v400_extruder_0.def.json” file in the “share\cura\resources\extruders” directory in the installation path.

  3. Place the “flsun_v400. stl” file under the “share\cura\resources\meshes” directory in the installation path.

  4. Close all open CURA software and add V400 after opening it again.:

the refefenced files are all on the drive;

i didnt need to do this as cura 5.3.0 has a profile for the V400

Thank you. I knew this however, the cura profile one would expect to be able to replicate the quality of the pre sliced files with Cora stock profile. I used the chep cube and could not duplicate it. I then used the pre sliced file to build a profile that did not match the included profile. I don’t really like cura much and especially as the PS improvements of the alpha 6.

I have been tinkering the profiles since. I am now getting good quality top layers. Faster prints that cura so I can actually print slower and get the same speed at the same layer height. I don’t understand how and it is model dependant but I am not arguing.

The inclusion of clipper coding I have yet to get a handle on the cura acceleration is bonkers.Too fast way way too fast. I don’t know if the cura profiles are actually sending the acceleration they list. 8000mm/s it runs so fast that the print quality and strength is poor.

I almost have my set of prusa slicer profiles dialled in for my needs and plan to publish them once I am happy with them. You can see the difference the stock cura and an early version of my prusa slicer version. I have it slightly faster now it is within 0.5% on the cube. Some files are faster some slower but all are in 5% of each other. That is with acceleration not on in PS. I still need to dial that in the alpha made the difference.

really like my V400 but my assembly revealed a pia flaw in the design;
wondering if others have seen this and maybe have other workarounds;
the referenced flaw is the assembly that fits into the ceiling of the cage that handles the filament run-out;
it isnt all that hard to fit into the ceiling But in my experience the filament , feeding from above, always has a little bit of bend to it, sometimes a hair of a twist ; the combo of bend and twist makes it less than 50% reliable that the filament will feed all the way thru that assembly , it just knocks against the steps inside and stops feeding;
so rather than just bypass the runout assembly i make it “free-hanging”, it doesnt set into the ceiling anymore it just hangs from its wires** that Are still attached to their connection points on the ceiling but the run-out assembly hangs usually about 5 inches below the ceiling; the filament still feeds thru but i have to manually guide each new spool; (yes, i do angle cut the filament before feeding it thru);
i dont like that arrangement but that was my first go at a fix;

other ideas ?

** terrible, i know, but at least the assembly is pretty light

I really don’t have any issues with feeding filament. I have a sidewinder x1 and if it is not really close to perfectly straight it sneaks out sideways missing the extruder gears completely.

The Fsun is far better so I don’t have a problem (in comparison) my other printers have far better and far worse filament paths so the V400 is kinda in the middle.

can’t wait for your sharing, i bow to your acceleration knowledge and will use your recommendations ( FLSun V400)

looking ahead, the search for a spare nozzle for the V400 was quite problematic; flsun doesnt have any accessories for the v400 listed on their site (only the SR,etc);
the only CHT nozzle on amazon was out-of-stock;
it seems the longer throat on the v400 stock nozzle is there for the “high-low”; there are some other V6 nozzles that can be had that have the shorter throat ( like 5 threads instad of 9);
i did find one long one that explicitly said “CHT clone” in the title of the product, wasnt particularly cheap

I am not sure about how good the CHT clones are now as I haven’t had a chance to try any recently. But I remember when some of the first clones started coming out they actually performed markedly worse than the standard V6.

Hopefully they have improved since then but that is something to keep in mind.


i contacted flsun about any means of obtaining extra nozzles; they replied that they make their own nozzles;
in addition they said i could paypal 20 USD to them and they would send me 3 nozzles;
i dont use paypal so they sent me the following (never encountered such a mechanism in all my online shopping, good idea tho):

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