New Tuning Instructions Wiki Page

Hello Jake,

I am working on a large hexacopter myself with a similar setup (30 Inch Props on 100KV Motor). I have completed the assembly and Pixhawk setup and done all the tuning setup according to the new tuning guide. I will be attempting a first flight soon and wanted to know your experience with first flight and what changes did you made from default parameters specifically the PID gains.

How different are the gains now after tuning and fine tuning. A screenshot of Extended Tuning page from Mission Planner before and after tuning would be a great help, or perhaps you could share the .param file.

Many Thanks

First flight was with default PIDs. After conducting an auto tune PID values were in the middle of the specified range, I can post the specifics at a later date, but not at the moment as the aircraft is being used for a project. Do be cautious with the values after the tune as we attempted a tune with the aircraft that returned very low values, around 0.6. We are not sure what caused this, after a crash and a second tune we got values that made more sense.

With default PID gains and MOT_THST_EXPO set appropriately you should be able to safely fly the aircraft. Best of luck!

I’ve got a question regarding prop size and Octoquad/X8 config;
A few key parameters can have initial settings based on prop size, so how do we treat the X8 with two props (the same size in this case) on one arm?

I think we would still treat this as just one size, for example 1555 props upper and lower = 15 inches in all the above posts and parameters, and we wouldn’t try to sum them (30 inches) or do anything special.

I’m not as sure about an X8 config with different size props (and possibly different motors too) for top and bottom. For example, upper props are 1855 (18 inches) and lower props are 1555 (15 inches) probably with high KV motors for lower props.
Would we :

  • Try and average the two, 16.5 inches in the example
  • Pick whichever you think will have the most effect (thrust, drag) 18 inches

and use that for the calcs in the new tuning guide.

Although I’m using props of the same size and same KV motors for upper and lower, I read where people think there’s merit in using slightly smaller higher pitch lower props and high KV lower motors - so I wonder about the tuning intricacies of such a config. Still I’m suspecting the difference in prop sizes (and potentially coupled with motor KV) wouldn’t make much difference.

All thoughts welcome

1 Like

This is correct.

If you want better than that you need to start measuring the thrust curve.

Yes there are lots of theories out there but most of the data has been produced without considering how multirotors are configured. For example most of the data is based on torque matched upper and lower blades. This is not the way an X8 aircraft will drive the props so it is not relevant for those aircraft.

Thanks a lot for your reply Leonard - I think I understand your answers, it certainly clears up some things for me.

I put together this spreadsheet for calculating some initial values based on the new tuning guide. You will need to judge for yourself if the calculated values suit your craft.
You should probably read and understand the new tuning guide to know what these new values mean.

WARNING: formulas are derived purely on eye-balling the graphs in @Leonardthall 's guide and recreating them to gain some formulas. The graphs I recreated are on separate tabs and you don’t need to look at them unless you feel like updating them and putting changed formulas back into the main tab.

  • Enter your prop size in inches, and the number of LiPo cells.
  • Copy/Paste the calculated values into notepad++
  • Search, Replace
  • Select Search mode “Extended”
  • Find what: /t {tabs}
  • Replace with: , {commas}
  • Save As some_filename.param

Apply the new .param file using Mission Planner or similar - I find this quicker and easier than manually finding all the parameters and trying to set them without making mistakes.

Everyone is free to provide feedback, modifications or otherwise.


Thanks, very great work!

Thank you for sharing.


Good work, handy, very handy.

I’ve simplified and fixed a couple of things in this updated sheet, please download and it try out while I work out how to get it functioning in the Tuning Process Instructions doco.


It looks a little cleaner and I like how you separated out the battery settings from the others. The new suggested settings are appreciated. I noticed that three parameter have been removed from the new spreadsheet:


I am just curious what was the reason for removing them?

It’s good to know someone is checking :slight_smile:
For those settings the defaults are the correct settings and shouldn’t be changed unless you undertake a little further investigation. I was keeping in mind this spreadsheet is for initial setup, and for first-time builds.
They’d been included before because I was tweaking them previously and needn’t have been in that old spreadsheet.

1 Like

I updated my spreadsheet again to fix mistakes in parameter names, please download a new copy


That is looking good mate. The values seem to work well accross the full range of aircraft that are practial right now.

Well done!

That spreadsheet is awesome. It matches the hand calc values that I do all the time. What would be super cool is… if you could export those vales into a text file that I could use to upload into MP :slight_smile:

I really do think there you be a “How to Setup your Multirotor with AP” sticky that includes this sheet as well as a link to the tuning page.

There seems to be a bunch of folks posting their “I crashed” or “it just does’t fly right” type of threads that never set all the initial tuning parameters before their first flight.

That is just what you can do, copying the data and import them to your FC (via a quick edit in notepad ++)

I did try that, and yep… Copy, add in the comma and good to go

Here’s the notepad++ instructions

  • Enter your prop size in inches , and the number of LiPo cells .
  • Copy/Paste the calculated values into notepad++
  • Search, Replace
  • Select Search mode “Extended”
  • Find what: /t {tabs}
  • Replace with: , {commas}
  • Save As some_filename.param

I toyed with the idea of getting the spreadsheet to generate a param file but then you lose cross-platform compatibility, and it gets quite complex.
It’s already proving difficult to get it working as an “online” interactive sheet or calculator, but I haven’t given up yet.


Great work so far. It’s much easier than having to look up the tuning page everytime in order to remember all the settings

Was going to suggest something in javascript to post online. Should be able to host via github pages if you keep it simple.