Have you balanced the propellers?

(18-Jun-2017, 10:35 AM)unseen Wrote: Have you balanced the propellers?

Hi Unseen, yes that is the first thing I do when I get new props.

(18-Jun-2017, 02:40 PM)Keyboard Kid Wrote: Hi Unseen, yes that is the first thing I do when I get new props.

Well, that strikes prop balance as being an explanation for the (quite large) variation in thrust.

   

(19-Jun-2017, 07:24 AM)unseen Wrote: Well, that strikes prop balance as being an explanation for the (quite large) variation in thrust.

Hi Unseen, I think I have found a perfectly reasonable explanation for that variation in thrust. have a look at the photo attached and you will see that all three prop bosses are different sizes indicating to me at least that all three props came out of different molds.

Here are the prop boss thicknesses from thinnest to thickest.

(a) = 6.32mm (soft)
(b) = 7.07mm (harder)
(c) = 7.76mm (hardest)

Also there are variations in the stiffness of the props themselves with the thickest being the stiffest and the thinnest being very soft. No doubt blade flexing reduces the thrust or increases it. Sadly I did not realise this at the time and I have no idea of which prop gives the most thrust. To put that test jig back together again is a real chore, but if you blokes so desire I will do it just to please you.

Personally I have learned a valuable lesson from this and I will be subjecting all new props in future to much closer scrutiny.

KK

   
Howdy Boys, I have been meaning to do this for some time and never seem to get around to it.

Back In 1968 Silvertone invented a frequency control system for R/C transmitters based on the bandwidth of the R/C system in question. Each transmitter was given a frequency key the width of which was proportional in scale to the bandwith of the TX. Thus a 20KHz TX was given a 2" key, a 10KHz TX a 1" key and so on. This allowed for the maximum use of our allocated frequency block.

When not in the keyboard the key was to be plugged into the TX rendering it inoperable until the key was removed. This was called frequency interlock and all Silvertone TX produced from 1968 on was fitted with frequency interlock. The aim was to reduce frequency accidents in R/C model clubs. This was all before 2.4GHz came into operation. There were only two conditions. The key was in the board so it was safe to fly or the key was in the TX and completely inoperable. Thus no shoot downs.

The Silvertone keyboard was eventually to become the Australian standard frequency system and was used in most clubs throughout Australia.

Thus I became the "Keyboard Kid". So you see, absolutely nothing to do with music. Neat wot?

KK

Haha thanks for that! You know, when i read your name on this forum for the first time, i was tempted to ask "do you intend to fly using keyboard and mouse" lol ... so thanks for clearing that up.

(19-Jun-2017, 01:28 PM)Keyboard Kid Wrote: Hi Unseen, I think I have found a perfectly reasonable explanation for that variation in thrust. have a look at the photo attached and you will see that all three prop bosses are different sizes indicating to me at least that all three props came out of different molds.

Here are the prop boss thicknesses from thinnest to thickest.

(a) = 6.32mm (soft)
(b) = 7.07mm (harder)
(c) = 7.76mm (hardest)

Also there are variations in the stiffness of the props themselves with the thickest being the stiffest and the thinnest being very soft. No doubt blade flexing reduces the thrust or increases it. Sadly I did not realise this at the time and I have no idea of which prop gives the most thrust. To put that test jig back together again is a real chore, but if you blokes so desire I will do it just to please you.

Personally I have learned a valuable lesson from this and I will be subjecting all new props in future to much closer scrutiny.

KK

Wow!

That's completely unacceptable variation. What brand are these props? I'd like to avoid accidentally buying them in future!

(19-Jun-2017, 05:13 PM)unseen Wrote: Wow!

That's completely unacceptable variation. What brand are these props? I'd like to avoid accidentally buying them in future!

Hi Unseen, they are all branded APC 12 x 6 but do not be too hard on APC yet. I believe what we are looking at here is an evolutionary process where APC has over time improved on this prop style. Just be aware that is all.

From memory I bought some of these 12 x 6 props from two suppliers and some may have been from an older stock batch.

KK

(19-Jun-2017, 04:50 PM)fftunes Wrote: Haha thanks for that! You know, when i read your name on this forum for the first time, i was tempted to ask "do you intend to fly using keyboard and mouse" lol ...  so thanks for clearing that up.

No problem FF, glad to be of service.

Now some help from you if you do not mind.

I would like to load the iNav software into the Hero to give that one more try.

I am a complete dunce with this stuff.

How do I remove the original program and reload the INav firmware?

I have installed the configurator already.

Where to from there?

Regards,
KK

Hi KK, I just flashed iNav onto my Beerotor board last night and it was a breeze.
Download Impulse RC Driver Fixer and save in a convenient place (I just saved mine in downloads
Open iNav configurator and click on firmware flasher (top-left corner of main screen
Choose your board from the dropdown
Choose the most recent firmware for your board (1.7)
Enable no reboot sequence and flash on contact
DO NOT enable full chip erase
Click on download firmware (online)
Now you'll have to put your board in bootloader mode by either jumping the boot pads or holding down the boot button then plug your board into your computer
You can now release the boot button or remove the jumper. You should have a solid green LED which indicates you're in boot mode
Now the important part - go to your saved Impulse Driver Fixer and open it, you'll get a screen with an indicator bar that will load up in a few seconds and give you the message "driver fixed"
In iNav, click on flash firmware. If all goes well you'll see the new firmware being loaded onto your board and will get the message "successful"
You should be good to go

(21-Jun-2017, 04:48 AM)RENOV8R Wrote: Hi KK, I just flashed iNav onto my Beerotor board last night and it was a breeze.
Download Impulse RC Driver Fixer and save in a convenient place (I just saved mine in downloads
Open iNav configurator and click on firmware flasher (top-left corner of main screen
Choose your board from the dropdown
Choose the most recent firmware for your board (1.7)
Enable no reboot sequence and flash on contact
DO NOT enable full chip erase
Click on download firmware (online)
Now you'll have to put your board in bootloader mode by either jumping the boot pads or holding down the boot button then plug your board into your computer
You can now release the boot button or remove the jumper.  You should have a solid green LED which indicates you're in boot mode
Now the important part - go to your saved Impulse Driver Fixer and open it, you'll get a screen with an indicator bar that will load up in a few seconds and give you the message "driver fixed"
In iNav, click on flash firmware.  If all goes well you'll see the new firmware being loaded onto your board and will get the message "successful"
You should be good to go

Thanks very much Reno.

My eyes were spinning after reading that but I am sure I will manage taking it step by step.

Regards,
KK

To make it easier, do a Youtube search for "flashing iNav firmware". There's a vid by Blue Falcon that explains this process

(21-Jun-2017, 01:29 PM)RENOV8R Wrote: To make it easier, do a Youtube search for "flashing iNav firmware".  There's a vid by Blue Falcon that explains this process

Many thanks Reno. I will keep you posted on progress.

To confirm, is this the flight controller you're using?
http://www.ttrobotix.com/product/hero

(21-Jun-2017, 03:59 PM)RENOV8R Wrote: To confirm, is this the flight controller you're using?
http://www.ttrobotix.com/product/hero

Just a heads up - if it is this one, you won't be able to flash iNav onto it, as it's closed-source.

If it's the AirHero F3, you're OK