My 2020 project - Taft Viper - Completed - flight video added

Aireal Anarchist

Elite member
great project Caroline, I am watching this build, if you dont mind could you refresh my memory on that head tracker device you installed, are you still happy with it any issues

thanks
 

CarolineTyler

Legendary member
great project Caroline, I am watching this build, if you dont mind could you refresh my memory on that head tracker device you installed, are you still happy with it any issues

thanks
Still haven't tested the head tracker in anger. It should be fine but until I'm flying with it I can't recommend it. Have noticed that the tracking unit needs to be still and flat when turning on or it doesn't calibrate correctly. Hopefully testing this Sunday, along with a 1.3Ghz video transmitter on the mini talon.
 
Last edited:

CarolineTyler

Legendary member
Progress...
Servos fitted for the rudder and elevator.
IMG_20200613_181036251.jpg
Can you see the issue? The elevator is acting more like ailerons. Looked up the servos I'm using and it doesn't have a reverse version. So I've ordered two servo reversers as I'm also going to need one for the flaps.
 
Last edited:

PsyBorg

Wake up! Time to fly!
Are you running those off a servo tester? They are physically positioned correctly to work as two channel elevators so all you do is reverse one channel in the radio once its plugged in to the receiver. This is common on jets so you can set up equal control changes better at higher speeds.

Two props pushing slow air across an elevator on single channel set ups isn't to susceptible to unequal thrust. Air moving from 2 edfs fast or slow are more likely to be unbalanced thus the need for separate and finer control on each surface with the smaller throws being more sensitive at high speed.
 

CarolineTyler

Legendary member
Are you running those off a servo tester? They are physically positioned correctly to work as two channel elevators so all you do is reverse one channel in the radio once its plugged in to the receiver. This is common on jets so you can set up equal control changes better at higher speeds.

Two props pushing slow air across an elevator on single channel set ups isn't to susceptible to unequal thrust. Air moving from 2 edfs fast or slow are more likely to be unbalanced thus the need for separate and finer control on each surface with the smaller throws being more sensitive at high speed.
Yes, a servo tester, I was going to merge the two elevators to a single channel, adjusting physically for slight differences. I have a seven channel receiver coming for this which includes basic stabilization so cannot run each elevator servo off a different channel. I thought about reversing the direction of one of the servos but the control horns on the surfaces will not allow for that.
The airflow from the EDF doesn't flow over the surfaces.
 
Last edited:

PsyBorg

Wake up! Time to fly!
If you flop the servo on its other side you could custom bend your own control rod to make like a larger z bend to accommodate the alignment change. Im sure you have tons of control rod wire with all the building you do.
 

CarolineTyler

Legendary member
On one build to save weight and it's a bit of a pain but I reversed the wires on the servo motor
Would you also have to change the wires to the potentiometer also? that's fiddly!!!! I'm not hunting down grams on this build - if I can keep the all-up weight around 3 to 3.5 kg, I sould be good :)
 

CarolineTyler

Legendary member
Spent several hours fitting the front retractable wheel on my TAFT Hobbies Viper. The steering servo and it's linkages are so fiddly and their geometry is really difficult to get right. Doesn't help that I'm still waiting on the right screws to secure the retracts to the wing.
Still to do...
  • Wing lights (easy)
  • Receiver fitting
  • Final mounting of the ESC, undercarage sequencer
  • Pilot fitting (may 3D print one)
  • Final mounting of the EDF (properly closing up the access hatch so it looks clean
  • Wiring extentions to be made and tidying. bought myself a proper crimper for the dupont connecters - so much better than using needle nose pliers!
  • Buy the batteries - that will be from next month's pay
  • Final assembly and getting the CofG right
Fly it - o_O
 

CarolineTyler

Legendary member
Done this week ..
  • Wing lights fitted and wired each with the correct in-line resistor to limit current. Designed and 3D printed LED clips to hold them secure.
  • Bought 2x 5000 6S batteries, arriving next week
  • Undercarriage secured with screws that turned up on Wednesday
  • All servos and undercarriage retracts with their linkages in place.
This weekend...... wiring. Got some 8-way connectors that I hope to use for the wings so they can be removed, this plane is pretty big!
 

CarolineTyler

Legendary member
Wing connectors done and what a hassle, I was up till 1am last night !!!!
The wings can now be easily disconnected with two screws and one multiway connector.
Issues found...
  • The three analogue servos for the gear doors do not play nicely with the other digital flight surface servos - replacement digital servos ordered!
  • The sequencer for the landing gear and doors is not working for the front gear door (the sequence is wrong for that and it's not adjustable) - will use an FMS one for that - ordered!
Finalised the ESC location and made a small support for it so there will be no chance of it moving when glued in (that will be the last thing). Set up the ailerons and flaps, three rates for the ailerons and a motor cut. Also set the failsafe.

My soldering iron bit is knackered so I cannot finish the tail feather connections at this moment. Two 5000mAh 6S batteries ordered (ouch!) and still to find the 'perfect' pilot figure.
Here's a few piccys of the plane on it's mains - it's looking fantastic.
IMG_20200628_152316028.jpg IMG_20200628_152326506.jpg IMG_20200628_152339659.jpg IMG_20200628_152410923.jpg
 

CarolineTyler

Legendary member
This has taken so much longer than I was expecting ---- Those DuPont connectios are a complete pain in the arse!!!
That the landing gear, flaps, ailerons all working. All digital servos.
Had to totally redo all the wiring, the idea I had to reduce the number of + and - cables backfired completely. :(
 

CarolineTyler

Legendary member