@oliof As you said there is a peak at very low frequencies, don´t know if enough high as to be a problem but there it is. Also I tested with and without a reinforcement in the X axis (I added a L shaped aluminum of 10x20mm all the wide axis lenght) and the peak around 40hz is now smaller but the VFA is more notorious in the printing, I will still try to dig some improvements at low speeds.
Here is the graph with the totally helpfull new Input shaping plugin:
@dc42 there is no change in terms of configuration, the file is the Ripple_JERK_test.STL anyone can download in thingiverse.
I mean this one:Ripple Jerk test Thingiverse
@zapta that's rigth they use to reinforce but with the accelerometer i measured the amplitudes with and without a reinforce and it does not vary a lot. Anyway if that's the case both x printed sides will ave simillar quality and it did not happen.
Anyway again I am waiting for a 10x10mm square cf tube to arrive and add to the rig.
Hi guys! I wanted to ask for some help here to the speed gods 
I am tuning the printing parameters in my printer, a corexy with a duet wifi. I did printing tests to setup the accelerations and jerks after I tuned properly the input shaping and the presure advance. I recorded the next parameters after trials:
M204 P3000 T1000 ;accelerations
M566 X480.00 Y300.00 Z420.00 E600.00 ;jerks(instant speeds)
M572 D0 S0.0375 ; pressure advace
M593 P"mzv" F42.50 ;input shaping
Temp 200
PLA Smartfill.
And this are the results:
From left to right is front x axis, right y axis, rear x axis and left y axis. Also from top to bottom is from 250mmxs to 50mmxs
At 50mxs there is very VFA visible apart from that ringing. But don't know how to improve that ringing 🥲
The machine has an aluminum 4040 structure so is pretty solid as you can see:
The linear rails in x and y are usongshine MGN9H with Z1 preload, there was no Z0 availables.
Forget to say the retractions are them all in the corner between tha face with the x and the y in the model 0.8mm at 900mmxm retraction speed. The hotend is a Phaetus Rapido with a 0.4 CHT nozzle.
@andreic did you tried to reinstall the previous version so you can check if it is something related to the fw or the config file?
@bberger thanks for the explanation! I will try it so I can see what gives better prints
@dc42 thanks a lot for the response! I not really understand yet the damping factor and another things related to the use of the input shaping and how to read it from the graph.
I think I will go for the 12mm belts (6mm ones was just a test to confirm with the module what I suspect by eye sight) but you did not mention EI2 or EI3, are them not a good choice for this frequency?
I tried to use the new plugin but can´t undertand how it works, is there any guide or reference page to check how it works?
Thanks again!!!
Hi there, I recently installed an accelerometer and did some readings. I am comparing the same system, first time with 12mm gt2 belts and after 6mm ones. All the rest is the same. The test was 200mm , at 10.000 acceleration and 1000mmxs.
As far as I can understand the 12mm is better because they have less amplitude and less wide peak. What do you guys think about it or can you point me something I can do better?
@matthiasweiss not yet as far as I was checking the same, we still need to wait a little bit more
@jens55 problem is if you can see there you can see it by far distance in more slow "quality" prints and we are trying to find yet if it is extruder related or fw related
@luke-slaboratory did you test your orbiter with some cube at slow speeds like 30mm/s and 0.2mm per layer?
Can you please say more about your setup? I mean, is it a comercial orbiter or printed one? What stepper does it use? And what kind of printer do you have?
The artifacts we discussed here and in another thread are more vissible at low speeds and thinner layer heights due less extrussion requires.
@donstauffer yes I detected similar improvement in my prints if I increase the speed regarding the periodic rippling but if a piece is small or need to reduce speed to print it the problem will be there.
Right now I am refining the extruder because just in case and of course a smoother meshing and movement never hurts.
I also did a test printing at 180 degrees instead of 200 as someone advised to increase back pressure but it did not work at all so the more test I do the more prone I am to think in something fw related with small speed on the extruder because it not only happen in a sherpa extruder but also in "good" ones like BMGs
@o_lampe I think I get what you say but can you post a pic or drawing bout what you say exactly?
@phaedrux what can I do to change fw? Because the latest test was done with the rc3 and the previous one with the rc2.
Regarding the extruder change it is difficult because it involves a total redesign on the X carriage, maybe I have enough time to adapt it for a bmg again or do you sugest another thing to do and test?
@donstauffer Maybe I did not explain properly but after all tests I did my only conclusion is that the artifacts are not related to XY moves but extruder moves. Of course there is a little bit ringing but also in the ringing due acceleration and deceleration I can see the periodic patron that gives the extruder. I don´t know why because I am not an expert in the firm or the internal management that the duet firmware do but as far as I can see and understand there is something different in my duet wifi between extruding slow at 30mm/s and 60mm/s that makes not smooth the extrusion at low speeds in straight extruded lines.
Today I ordered a LDO 8 pinion stepper so maybe having more steps per mm (55 insted 44 at full steps) and different inductance and such will help. It will arrive in about two weeks.
@gloomyandy it is difficult to take a pic of it but here it is. And the test is simple, just did an air extrusion lije when you want to prepare the hotend or simillar, just send thw G1 F6 E50 command on the console and that is all.
Well, this afternoon did a few more test, you know just for the pleasure of havi g the same result always hehehe
I printed at 30mm/s all test and the changes was:
So I don't know what rlse to try but I am more than convinced that it is related on how on the duet wifi are managed slow moving as it happens on the extruder at such speed.
I also extruded on the air with the printed stopped 50mm of filament at 6 and 1 mm/s and the extruded filament has the pattern I see on the printed objects so it is like the stepper movement at low speeds is not smooth at all or something weird happens with back pressure or something like that...
@donstauffer I don't know, that's out of my knoledge. What I can say is I inspected the gcode file and the gcode for the cube sides is go from A to B extruding C ammount of plastic at F speed so the extruder has one only order to follow and the cilinder has small tiny segments to be printed in the same way, if I can this afternoon will try to print a cube of 20mm and another of 80mm to see if it vary something but I think it will not.
Maybe @dc42 can shed some light to this issue 
@mrehorstdmd no, that's not the reason, if I were overextruding the perimeter will be higher than 0.4mm I set but consistent and that's not the point and also y speed is double or later height double should show another different issues.