# Problems with velocity and accel limits in Klipper (Elegoo Neptune 4) **URL:** \ **Category:** General Discussion\ **Created:** [February 23, 2025, 12:45pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167 "2025-02-23T12:45:23Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![Pablux](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/pablux/32/17761_2.png) [@Pablux](https://klipper.discourse.group/u/Pablux)\ **Post date:** [February 23, 2025, 12:45pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/1 "2025-02-23T12:45:23Z")
### Basic Information: Printer Model: MCU / Printerboard: Host / SBC klippy.log _Fill out above information and_ **_in all cases attach your_ `klippy.log` _file_** (use zip to compress it, if too big). _Pasting your_ `printer.cfg` _is **not** needed_ _ **Be sure to check our “Knowledge Base” Category first. Most relevant items, e.g. error messages, are covered there** _ ### Describe your issue: …Hi. This is my first post ever, so sorry in advance. I`m trying to speed up my Elegoo Neptune 4 but everytime I`m trying to set SET\_VELOCITY\_LIMIT VELOCITY=1000 or SET\_VELOCITY\_LIMIT ACCEL=30000, it goes back to 500 mm/s. I’ve tried to make a macro to set this in the middle of the printing or at the start, I’ve set the machine limits in the printer.cfg and unplug the machine screen but none of this worked. Is it something that I’m doing wrong or is it that Elegoo’s klipper is somehow blocking it…? Any help would be appreciated. Thanks in advance. ---
**Author:** ![EddyMI3D](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/eddymi3d/32/1981_2.png) [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)\ **Post date:** [February 23, 2025, 1:11pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/2 "2025-02-23T13:11:23Z")
Hello @Pablux ! Please give this information. Most important: The klippy.log. ![grafik](https://global.discourse-cdn.com/free1/uploads/klipper/original/3X/8/6/86cb5a6adee67a028e6a84944dd2d56a77946730.png) ---
**Author:** ![Pablux](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/pablux/32/17761_2.png) [@Pablux](https://klipper.discourse.group/u/Pablux)\ **Post date:** [February 23, 2025, 1:15pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/3 "2025-02-23T13:15:09Z")
[klippy.zip](https://klipper.discourse.group/uploads/short-url/4tOYiT4KMhAIN4IianhTemKtKed.zip) (797.6 KB) Hi, this is it. Thanks! ---
**Author:** ![3dcoded](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/3dcoded/32/20297_2.png) [@3dcoded](https://klipper.discourse.group/u/3dcoded)\ **Post date:** [February 23, 2025, 2:29pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/4 "2025-02-23T14:29:27Z")
@Pablux Most likely your slicer is overriding your values. If you want to print at 1000mm/s, you’ll need to update your slicer settings to reflect that. Also, I’m not really sure how you’d manage 1000mm/s on a bed slinger like the Elegoo Neptune Max. I have a Prusa MK3S Bear (smaller, lighter bed) and I’ve managed 600mm/s with 20k acceleration after upgrading my steppers and a lot of tuning. I’d start with 300mm/s with 5k acceleration and work your way up. Also, your hot end will have to keep up with your speed. It looks like the Neptune 4 can do around 20mm3/s. With a 0.4mm nozzle and 0.2mm layer heights, that’s 250mm/s. You’d realistically only hit that speed on infill, and exceed it on travel moves. You still want to keep your perimeters at 150-200mm/s max if you want good quality. Some good reads from Ellis’s tuning guide (I’d recommend going through the whole guide, but these links cover the absolute limits): - [Determining Maximum Speeds and Accelerations | Ellis’ Print Tuning Guide](https://ellis3dp.com/Print-Tuning-Guide/articles/determining_max_speeds_accels.html) - [Determining Maximum Volumetric Flow Rate | Ellis’ Print Tuning Guide](https://ellis3dp.com/Print-Tuning-Guide/articles/determining_max_volumetric_flow_rate.html) - [Determining Motor Currents | Ellis’ Print Tuning Guide](https://ellis3dp.com/Print-Tuning-Guide/articles/determining_motor_currents.html) ---
**Author:** ![Pablux](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/pablux/32/17761_2.png) [@Pablux](https://klipper.discourse.group/u/Pablux)\ **Post date:** [February 23, 2025, 2:57pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/5 "2025-02-23T14:57:05Z")
I changed the noozle to a Volcano nozzle and trying to reach more than 500 mm/s and do some testings to see how fast it will be able to print. Just tried to override the speed in the slicer but didn’t work. When I change the speed it works for some seconds but it goes back to 500 mm/s no matter how many times I change the limit value ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [February 23, 2025, 4:28pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/6 "2025-02-23T16:28:10Z")
As indicated above, the general limits are set forth in the `[printer]` section, but these limits can (and will) be potentially overwritten by your slicer settings. If there are such settings in your sliced G-code file, you can set what you want via a macro or in the `START_PRINT` script, but it will quickly get overwritten by the G-code commands from the sliced file. ---
**Author:** ![3dcoded](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/3dcoded/32/20297_2.png) [@3dcoded](https://klipper.discourse.group/u/3dcoded)\ **Post date:** [February 23, 2025, 5:20pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/7 "2025-02-23T17:20:45Z")
> [@Pablux](#): > > I changed the noozle to a Volcano nozzle That should be faster than the original hot end. For 500mm/s, you’ll need 40mm3/s. Keep in mind only your infill and internal solid infill should be printed that fast if you want good quality. You might want to do some flow rate benchmarks ---
**Author:** ![Pablux](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/pablux/32/17761_2.png) [@Pablux](https://klipper.discourse.group/u/Pablux)\ **Post date:** [February 24, 2025, 7:32pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/8 "2025-02-24T19:32:35Z")
I changed the parameters in START\_PRINT and in the slicer (Orca Slicer) but it doesn’t stay. Somehow whe it starts printing the velocity goes back to 500 mm/s, something overrides it and goes back to the old limits. Does anyone know what’s going on? Is it that somehow the Elegoo’s Klipper is not allowing me to do it? Is there any way to get full control of the velocity or do I have to flash “non Elegoo” Klipper in order to fully control it? Thanks in advance. BTW, the Volcano hotend allows me to get better flow rate and extrusion at full speed than the usual Elegoo nozzle ---
**Author:** ![3dcoded](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/3dcoded/32/20297_2.png) [@3dcoded](https://klipper.discourse.group/u/3dcoded)\ **Post date:** [February 25, 2025, 6:45am UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/9 "2025-02-25T06:45:17Z")
Did you change the max speeds and acceleration in the machine limits section of Orca? ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [February 25, 2025, 7:35am UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/10 "2025-02-25T07:35:08Z")
> [@Pablux](#): > > Is there any way to get full control of the velocity or do I have to flash “non Elegoo” Klipper in order to fully control it? It is possible that Elegoo somehow crippled their Klipper version, but since they also seem to be violating the Klipper GPL license by not publishing their changes, this will be hard to verify. Whether you can run a pristine Klipper on this printer is equally unknown. See [3D Printers with Preinstalled and Modified Klipper Versions](https://klipper.discourse.group/t/3d-printers-with-preinstalled-and-modified-klipper-versions/20467) for some information on this topic. Generally, I would think it is a slicer setting thing. ---
**Author:** ![Pablux](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/pablux/32/17761_2.png) [@Pablux](https://klipper.discourse.group/u/Pablux)\ **Post date:** [February 25, 2025, 5:31pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/11 "2025-02-25T17:31:52Z")
Yes, I did, but it doesn’t work, it goes back to 500 mm/s, doesn’t allow me to go further ---
**Author:** ![3dcoded](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/3dcoded/32/20297_2.png) [@3dcoded](https://klipper.discourse.group/u/3dcoded)\ **Post date:** [February 25, 2025, 6:05pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/12 "2025-02-25T18:05:28Z")
Could you upload a G-Code file so I can inspect further? ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/klipper/original/1X/64419bf2aac6639e6ef5cef200dcd456b0a01ac3.png) [@system](https://klipper.discourse.group/u/system)\ **Post date:** [April 26, 2025, 6:06pm UTC](https://klipper.discourse.group/t/problems-with-velocity-and-accel-limits-in-klipper-elegoo-neptune-4/22167/13 "2025-04-26T18:06:09Z")
Closed on April 26, 2025, 6:06pm UTC This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.