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Dec 05, 2019, 05:26 AM
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Mark 2's Avatar
Quote:
Originally Posted by 19000rpm
I've got mine assembled and when going about setting the CG to 80 mm I found the heaviest battery I could use was a 2200 and that lines up with the back of the canopy opening. I've read where people are using 4000's and wondering how that is possible without adding weight to the tail.
I’m using 4s 4500 batteries, the front of the battery lines up with the marked line in the picture, no problem getting the right CG.
I didn’t add any weight at the back, but I have kept the water rudder.
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Dec 05, 2019, 05:40 AM
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Bill Glover's Avatar
IIRC the water rudder mechanism and pushrod are 30-40 grams in total (and obviously this is a long way behind the CG). So removing that does make it a little more difficult to balance. Adding custom paint jobs etc. on top of the standard finish would move the CG back of course, so then you might need that extra space in the nose to get it balanced.

It's not that unusual for ARTFs to be a bit nose heavy. My Tundra and ASW 28 both balance level without a pack on board!
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Dec 05, 2019, 07:57 AM
Registered User
Thanks guys!
Dec 08, 2019, 02:14 PM
Registered User
Out to the field with snow on the ground and a nice NW breeze in the 8 mph range at 32* for the maiden.

The Albatross took to the snow like a Duck takes to water. A couple of nice flights exploring the envelope, loops rolls, touch and go's and landings. Completely forgot to use the flaps on landing but plane slowed nicely dead stick with a small flare.

I haven't pulled the water rudder yet. It is very functional in the snow. Looking forward to many more snow ops before I get to try it out on grass and water.
Dec 18, 2019, 06:35 PM
Registered User

Differential thrust on DX 7


Hey guys I'm trying to program differential thrust on my DX 7 and not having much luck. Plugging my second motor into the gear channel. Can't seem to get the two mixing channels right. Advancing the throttle channel only revs up one motor. If I move the rudder stick to the right the o the mother revs up. Horizon Hobby tech support sent me this programming.
Mix 1 - Rudder to gear, Rates: 100 + 0%. Assign a switch to the mix.
Mix 2 - Rudder to Throttle, Rates 0% -100. Assign same switch as mix 1.
Any help is appreciated!
Dec 18, 2019, 07:13 PM
Registered User
Try this video. It should help you with differential thrust setup.
Differential thrust on Spektrum DX6 or DX9 (8 min 0 sec)
Dec 18, 2019, 08:14 PM
Registered User
I tried that and it doesn't seem to work because of the reverse ESC with the spektrum system. Maybe with the reverse out of the mix it will. Or if I'm missing something clue me in...
Dec 19, 2019, 10:46 AM
Registered User
Quote:
Originally Posted by 19000rpm
I tried that and it doesn't seem to work because of the reverse ESC with the spektrum system. Maybe with the reverse out of the mix it will. Or if I'm missing something clue me in...
What receiver are you using? I tried the AR636 but couldn't get everything to work so I went with the Lemon 7 ch stab+ .
Dec 19, 2019, 11:22 AM
Registered User
Quote:
Originally Posted by mburton47
What receiver are you using? I tried the AR636 but couldn't get everything to work so I went with the Lemon 7 ch stab+ .
As it happens I used a used AR636A which came from another plane. I had to use one servo reverser on elevator to work with the AR636A stabilizer program. Other than that it works fine less the differential thrust. Ordinarily I would have used a Lemon.
Dec 19, 2019, 11:40 AM
Registered User
I like to use the AR636 (store bought) and program it myself but couldn't get it to work on the Albatross and have differential thrust and reverse. The Lemon worked for me.
Dec 19, 2019, 12:32 PM
Registered User
Quote:
Originally Posted by mburton47
I like to use the AR636 (store bought) and program it myself but couldn't get it to work on the Albatross and have differential thrust and reverse. The Lemon worked for me.
Which Lemon did you use and what mixes allow both the reverser and differential thrust on a spektrum compatible Rx/
Dec 19, 2019, 01:17 PM
Head NEAT geek
Tom Hunt's Avatar
What am I missing here? The RX should not be relevant. All the mixing is done in the TX. The receiver just does what it's told. You just need enough channels to do all the functions.
Dec 19, 2019, 01:35 PM
Registered User
Quote:
Originally Posted by Tom Hunt
What am I missing here? The RX should not be relevant. All the mixing is done in the TX. The receiver just does what it's told. You just need enough channels to do all the functions.
The Rx needs how many channels to do thrust reversing and differential thrust? What are the mixes? Thanks.
Dec 19, 2019, 02:20 PM
Head NEAT geek
Tom Hunt's Avatar
Quote:
Originally Posted by 19000rpm
The Rx needs how many channels to do thrust reversing and differential thrust? What are the mixes? Thanks.
19000

I don't "DO" spektrum (I'm a taranis guy), but you would need a minimum of 7. something like this:

1 left motor (which also needs to drive 5)
2 aileron
3 elevator
4 rudder (mixed into 1 and 5 as opposites)
5 right motor
6 flap
7 esc reverse (which has to be mixed into 1 and 5)

The easiest and "safest" way to get this right is to do it on a spare Rx and put servos in the throttle channels.
Dec 19, 2019, 02:28 PM
Registered User
Quote:
Originally Posted by Tom Hunt
19000

I don't "DO" spektrum (I'm a taranis guy), but you would need a minimum of 7. something like this:

1 left motor (which also needs to drive 5)
2 aileron
3 elevator
4 rudder (mixed into 1 and 5 as opposites)
5 right motor
6 flap
7 esc reverse (which has to be mixed into 1 and 5)

The easiest and "safest" way to get this right is to do it on a spare Rx and put servos in the throttle channels.
Thanks.


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