Back with a new mini talon - questions

chris-s · April 07, 2017, 05:54:15 PM

Hi folks!

Its been quite a while since I last posted on here but I have been popping on from time to time to see whats going on. Up until last weekend it has been best part of a year since I've flown any fpv, but after dusting off the hex and helping a guy with his Vector equipped wing I think I've got the taste for it again. My hex flight at the weekend was 'eventful' and as a result I logged onto the forum on monday to see if BigNose was still around for a new skew (still to message him), and after seeing someone was 'shouting' about cheap MT's earlier in the week, I've just had one delivered today.

Up until now, my fpv fleet has been made up from a dji hex, bixler (deceased after a combat gliding incident) and a skywalker kitted with an APM and all the bits. Whilst the skywalker and apm combo flew great, I think my motor/prop combo wasn't the best and flight duration isn't as great as I had hoped and it's a pig to throw/launch as it has a horrible pitch-down at high throttle that I have failed to resolve.

I'm thinking of fitting the MT with a mini apm as I really like the features and am familiar with the how it all works. Is there anybody here who already has an MT with apm?

Are there any must-do/must-have points for the MT? I've already noted the cg on the build sheet was incorrect at 70-something mm!

I see there are quite a few 3d-printable MT parts around, anything in particular worth using? I like the idea of the 'front skid'.

Cheers!

Chris

SnoozeDoggyDog · April 07, 2017, 10:05:22 PM

Hi Chris
I posted up early this week about the 34 quid talons. I ordered a spare one that arrived yesterday.

I have only used a vector in the talon sorry and have just swapped it out for an MFD (bad maiden today).

But i can recommend the front skid highly as well as the ap bay and Runcam2/fpv mount. I'm running a sunnysky 2216 1250kv with a 8x5 prop on a 4s 8000mah battery. The wing chord if my serves is about 25.5cm which works out at a CG of about 8.5cm

Regards
P

FPVSteve · April 07, 2017, 10:21:39 PM

My Mini Talon I have set nose heavy, I can't get on with the recommended CoG at all ... it balances about 1cm in front of the CoG markers on the underneath of the wing. Having said that, I have my motor mounted externally on a flat mount glues to the back instead of inside the fuselage, so perhaps that's why.

Your mileage may vary but just make sure it isn't tail heavy, they don't like that one bit!

chris-s · April 18, 2017, 12:17:58 PM

Thanks for the replies.

I was rather hasty and ordered a set of four Hitec HS81 servos for my mini talon and then realised they were too large, at least for the tail end so I'm going to order some smaller HS65 for the tail at least, but do you think it would be ok to use HS81's on the wings?

Chris

FPVSteve · April 18, 2017, 03:15:12 PM

Should be able to - you'll need to cut extra foam out of the slots, but the MT's wings are pretty thick.

Coyote · April 18, 2017, 09:59:48 PM

HS81's will be fine

Loopdreams · April 19, 2017, 12:31:31 AM

I've got mine balanced on the servo wires or 65mm from the leading edge and it's really easy to launch and has good low speed handling. Feels like the CG could still go back a little too.

With the CG too far forward it'll be a pig to hand launch because the stall speed will be much higher.

English Turbines · April 19, 2017, 12:43:45 AM

Quote from: Loopdreams on April 19, 2017, 12:31:31 AM
I've got mine balanced on the servo wires or 65mm from the leading edge and it's really easy to launch and has good low speed handling. Feels like the CG could still go back a little too.

With the CG too far forward it'll be a pig to hand launch because the stall speed will be much higher.

Im just finishing mine now, Im going to use this as a starting point...It has to be right on this model..So pleased you didnt say " 6.5cms"....lol..

:vulture:

sstorrow · April 19, 2017, 10:21:44 AM

I have a CG at 50mm and it performs just fine. Never failed a hand launch with ~75% throttle. It's better to be nose heavy than tail heavy for a maiden, so i would start further forward and then gradually move it back as you get more confident in the airframe.

I might try moving it back a touch now that I've had a few successful flights.

Loopdreams · April 19, 2017, 10:45:09 AM

You should find it improves if you do that.

Whilst the old maxim that nose heavy planes fly badly and tail heavy planes fly once is largely true for planes with an undercarriage where getting up to flying speed is never usually a problem I think it accounts for at least some of the problems people seem to encounter with hand-launching various planes.

I've read lots of accounts of how the mini talon can be tricky to launch and won't slow down for landing. But with a correctly set CG neither of these things are true.

With more weight towards the front then to fly straight and level at a given airspeed requires more up elevator and the plane is therefore going to be flying along at a higher angle of attack. Which means that the critical angle of attack will come at a higher speed. If that speed is higher than the speed at which it can comfortably be thrown then you might have some problems. Often with a decent throw and enough power it will accelerate away and it'll all be fine. But it still won't be flying as well as it could.

A word of caution, though. When you do start moving the CG back and the plane starts flying properly the elevator will gain more authority so it's best to reduce the throws, preferably by moving the pushrods along the servo arm or the horn.