14SG -- Increase collective resolution around center stick

[cbrkhan]

This may be a general TX question.... I have just converted to 14 SG from a DX8. Loving the new radio. Only one minor issue, it feels like 14 SG does not have enough collective resolution around center stick..... I have to move the stick way up or way down to get a meaning full response from the heli. I have liner Throttle and Pitch curves programmed. I will try to explain with and example .... on my DX8, I was able to bounce the heli up and down (or a tick tock) with relatively small movements up and down from the center of the collective stick ........ With 14 SG if I want to do the same, I have to move the collective stick way up and way down to get the same effect.


This also has changed the feel that I am use to with during tick tocks and rainbows. I almost put the heli in the ground today because when trying to make a inverted stop in a rainbow, I instinctively moved the negative collective to where the heli would have stopped with DX8 .....but it kept going until I gave some more negative collective and heli stopped inches from the ground.

Is there a way to increase collective resolution around mid stick to match with what I am use to with? Also, is it just me or anyone else have the same experience?

[cbrkhan]

Anyone?

[jimmanyk]

Just a general thought, if your using expo it may work in reverse to the dx8.

[RC Mike]

I have never had that problem but I don’t use expo on collective. Also make sure that your pitch and throttle curves are correct. The pitch curve is what controls the sensitivity.
　

[Costas]

You will find that if coming from some JR [or the DX8] Tx's that the actual physical throttle stick travel is actually much less than on the 14SG.

Jr started this trend many years ago on some of their sets [back in ye old JR10SX, 10X etc days]. JR would fit throttle stick travel limiters on their heli sets. This effectively meant that less collective/throttle stick travel is required to get to full travel. It may have been done by design by input from Curtis Youngblood in those early years?

I have owned a JR10SX, 10X and a JR12X - All these Tx's came fitted from factory with stick limiters on their respective throttle/collective movement/stick. From memory, I think the DX8 is the same?

When I first purchased my 14SG back in April 2013 - I noted that the collective/throttle stick travel was uncomfortably long, as I was used to much shorter travel on my previous JR sets.

In the end, I cut some strips of hard plastic styrene and glued them in place at the top and bottom of the collective/throttle gimbal to physically reduce its travel. I chose the appropriate thickness to suit and after gluing them in place with 5 min epoxy, I simply re-calibrated the sticks. Worked a treat...!

[Bob O]

I actually prefer this change over JR, more precise control being the benefit for me.

If you do like mentioned above and physically limit the travel of the sticks, the 14SG has a feature where you can calibrate the stick for the new limits.

Sent from my phone

[msallua]

The Futaba 14sg has expo in collective?

[Costas]

Expo function is not the same as limiting the physical stick travel. Limiting the stick travel still allows for a linear response whereas adding expo does not.

More expensive sets have user installable/removable limiters so the overall stick travel can be tailored to the pilot's needs.

[cbrkhan]

Glad to know I am not the only one.... its juts a feel thing and maybe I will get use to it ..... but this feel/instinct took a long time and effort to develop...


Great Idea about physically limiting the collective stick and recalibrate ..


How about a little aggressive pitch curve? Something like



I have a liner curve
+100 +50 0 -50 -100
Change to say
+100 +65 0 -65 -100

Will this give me better pitch response towards center stick?

[Magneto]

Doing the stick mod is easy I used a couple pieces of wooden coffee stirrer and glued it in on the gimbal stops and recalibrated as Costa stated.

[cbrkhan]

Costas , Magento or anyone post a picture of this mod ….. How does placing stoppers work…. How did you test this mod before deciding on appropriate thickness? ….. on stock model the stick does not touch the physical stop ……… some stopper inside the gimbal stops and stick is still a bit away from touching the physical gimbal housing …


Do you guys mod such that your new glued on stoppers touch the stick and prevent it from going further?

Also, has anyone tries a more aggressive pitch curve to solve the problem or would this give me another bad habit?

[Costas]

Sorry but I had not taken any photos of the modification. If you open up the back and carefully look at the gimbal action with a flashlight, you should see how the gimbal is stopped at either end of its throw when moving the collective/throttle stick.

You will also see that there is plenty of room to place a small rectangular piece of material [one at each end of the gimbal] so that as the gimbal approaches its end of travel, the spacer becomes trapped between the moving gimbal and the gimbal housing - This will limit the gimbals travel.

You just need to select an item of the appropriate thickness. Like Magneto stated - a wooden stirrer stick or similar would be just about right if comparing to a JR radio. To give you an idea of the reduced travel - My collective stick is now limited in throw so that the small white ticker indicator stops at the second to last indicator at both ends of its travel.

I simply used some 5 minute epoxy to glue the spacers/limiters in.

Playing around with curves will not achieve the same thing as you cannot change the slope of your pitch curve with stuffing up its linearity.

[cbrkhan]

Thanks Costas .. Now I am clear on the mod and will try it soon ....

[cbrkhan]

Before doing the mod, I tried +100 +65 0 -65 -100 pitch curve today...... Its solves the issue for the most part ..... Tick Tocks are perfect and stops on rainbows are right where i want then to be ...
It was cold so i only flew 4 flights ........ will test some more later and keep this thread updated .....

[EdinTexas]

Would it be possible to calibrate the collective stick by simply moving it to the points of travel you want to be +100 / -100 while doing the calibration without actually gluing anything inside the gimbal?
If that's possible what would happen if you bang the stick against the stops? Overdrive the servos? Seems like there should be a way to prevent that as well.

[cbrkhan]

Originally Posted by EdinTexas

Would it be possible to calibrate the collective stick by simply moving it to the points of travel you want to be +100 / -100 while doing the calibration without actually gluing anything inside the gimbal?
If that's possible what would happen if you bang the stick against the stops? Overdrive the servos? Seems like there should be a way to prevent that as well.

I am interested to find this out as well. I may try this before i do the actual mod

[Costas]

If you calibrate the collective stick short of its actual physical end spot it results in a 'dead' area when the stick is pushed passed this chosen spot ie you will just find that the stick does nothing when you pass the calibrated end point.