Trex 500 Pro DFC BeastX, step J and ball links

[RontaryUS]

I have 15mm thanks to the secraft horns and this allowed me to be spot on blue for J (was not with the align arms in inner hole with 18mm servo center to ball). But the link is now hitting the AR on the elevator when just in red (1 click from purple...) in L because of the shorter horn...the binding is just as I describe. Works well in other directions/throttle positions. This gives me about 8* cyclic pitch (with +-12 in K for the collective pitch). On the secraft I can go down to 12 but because of the position of the servo it would make the binding worst and the geometry would become a bit weird (link/servo arm is not 90* already with these shorter horns. I kept the horns 90* to servo, not the links, hope this is correct, let me know if it should be the other way around...)

I tried reducing the pitch in K but same binding issue. If I lower the swash in G, the binding is on the aileron servos.

[BigIreland]

The amount of throw required to bind the servo arm doesn't look like much but actually is a lot because of how the DFC head works. You definitely want to run the same servo arms on all 3 cyclics. Also, remember that the binding you are dialing out is at the most extreme limits for the servo movement. Set it up with matching cyclics and try it out.

[RontaryUS]

BigI, thanks for jumping in. Am I interpreting your point point correctly that the DFC head design might require less cyclic pitch for an adequate roll rate?

With my setting (and maybe it is standard as my reference points are setup OK), the beastx is happy in point L (blue) between 10-12* cyclic, red in 8-10* range and purple when less than 8*. I am just on the edge red/purple and getting 8* with the slight binding described before but if 8* is enough because of the DFC design, I am happy with this...

I cannot find info from align on the required cyclic pitch for the 500dfc head...

[ddj74]

Coming in a hole on the arms may fix the binding being closer to 13mm spacing. Gives less throw and no chance of binding. I can set up the beastx at extreme max limits on my old 500 and never got any binding. Then i dialed it in from there to my flying preference.

[RontaryUS]

Spent some more hours. I finally reverted back to the align servo arms. I also changed the balls on the aileron servo arms to get a bit more resolution: now using short balls. I am in red on J at 6* (6.9 blue but I set it up at 6*). I now have plenty of throw in L without binding (blue light!): about 11.5* cyclic pitch whereas I was getting barely 8* with the shorter horns...

This is not perfection but I guess this is the best I can get. The geometry looks really good (straighter links and 90* angles). I read lots of guys are flying being in red on J without problem as far as set up to 6*. I'll just go fly and will see. Will report back when I get a chance to fly...

[mhills51]

You are using the short balls on the inter part of your swash? The align arms work just fine. I have been flying mine going on two years with the beast in red just shy of blue without a single issue.

Just checked it is the dfc helicopter kit so it has the dfc swash

[RontaryUS]

I don't see any advantage of changing the inner swash plate balls on the 500DFC head - would be too tight and they are not oriented to the outside so I think it would not change the resolution. I changed the balls on the servo arms for aileron. I put small balls (same as the one on the elevator servo arm). This gives me a bit more resolution and having them in the inner holes of the servo arms give me a red in J (instead of purple when I started this thread) and all other setup steps are right where they should be.

Fun fact: I read the french version of the microbeast manual (like to do that to get different perspective...). Same verbiage as the English version for J with the fact that you should adjust geometry if you don't get blue but if I translate literally the framed note it says: 'Always adjust to 6*....the LED is then secondary, red will also be acceptable'...

[mhills51]

the English manual states "the blue color of the status-led is secondary and just for information." In the yellow caution square on page 51.

[Phil79]

I had the same issue with my 500 pro dfc. With the align arms on the outer hole, i didnt get blue light on stp j. And when using the inner hole, i got barely the blue light, but i got binding on the antirotation bracket and in the tail boom case. Then i used servo arms with a 15mm hole, and i got easily the blue light, but i got more binding on the servo arms. So i found to be best using this 17mm servo arms,

http://www.espritmodel.com/aluminum-...futaba-m2.aspx

I used dremel on the antirotation bracket, and in the tail boom case. Also using shorther balls on the swash. Now i have blue light / 6° on step j, and 10.5° of cyclic throw on step l.

Im considering to buy this part, http://www.rc-tek.com/store/i2rc-tre...unt-p2302.html

With that part, the servo arm will not bind, and you could get the 12° of throw.