1:3 asg 29

[ARUP]

I bought this Robbe ~1:3 ASG 29 from SoaringUSA last year during a sale. It has a 5m span and the wing is in four parts. The fuselage is 1.78m so transportation and storage shouldn't be a concern... for me anyway. It is a very nice model and includes a fully detailed cockpit (with instrument cluster, seat pan and back rest, joystick, levers, knobs and seat belt harness), retract unit (no wheel?), forward hinged cockpit canopy accessed via a scale canopy vent with scale latch, nice gelcoat fuselage and hollow molded wings. I'll get more pictures as the assembly progresses. I'd like to get it ready for SLED Works next month.

The first order of business was to remove the retract unit so a wheel and servo could be installed. I would have paid an extra 20 bucks just to have the wheel in the kit! It needs to be ~100m dia. or less. I didn't have one so made a trip to the hobby store in Louisville, KY to get one. What I bought for ~18 bucks won't work so that was a waste of $$$ and ~2 hours driving time. I salvaged a foam wheel from the 'extra parts' bin and put an aluminum hub on it. It ought to last a few flights before a better wheel can be sourced. The retract unit had to be partially disassembled to fit the wheel and Hitec HS-5585 servo. The servo bay in the retract unit only has room for two mounting screws. The other locations are where standoffs are mounted. The servo will fit over the button head screws for the standoffs if no gromments are placed on the servo at these locations. I used 4-40 bolts and elastic or 'nyloc' nuts. The servo bay was drilled and tapped for the bolts. Lots of trial and error used to fit the pushrod without binding but getting full lock-to-lock travel.

One gear door hinge had come unglued so it will get repaired. The kit came with rubber bands attached to the retract unit and doors on the model 'in situ'. I guess the manufacturer did that so you could see how to rig it after getting the wheel and servo installed. They had to be cut in order to take the retract out of the fuselage. In lieu of using the rubber band method a torsion spring was fabricated so that the doors will stay closed when the wheel is retracted. The epoxy is curing as I type so more pics will show how it is done.





more...

[ARUP]

More pics! Here are some interior pics.The torsion spring was made as one unit. The 'M' end is bent to fit the inside curve of the fuselage. The 'ears' get attached to the doors and are formed in such a way so they 'pre-load' the doors to keep them closed when the wheel retracted. This has been done on other models and works great! No more rubber bands to break or coiled springs to hang on something. In the past one for each door was made using the music wire as the hinge pin. The door hinges on the ASG 29 are offset from the fuselage surface somewhat so just adding the torsion springs was prudent. The interior of the fuselage was scuffed with sandpaper then cleaned with a vacuum and then a damp rag. The springs were taped into the fuselage and a fiberglass patch with epoxy set at the end. Waxed paper and foam with weights put on this to cure.









Later Taters!

[Mosquito]

Nice work Michael!

I am pretty sure that this is the same ASG 29 that I have that was sold under HF Models. The retract is actually a pretty nice set up. It's nice that the rear bolts are keyed so that only the front two bolts need to be removed to take the unit out. It offers pretty good shock absorption. I love your torsion spring idea over rubber bands. Very nice.

You will like this sailplane. Like you said, it will fit into a small car with it's smaller size and wings that break down. It's a fast flying glider that will spin on you if you are not careful.

Looking forward to towing you up in a 'glass slipper' at Sled Works. It will be the first time I have ever seen you fly something other than an old timer!

--Tim

[ARUP]

Thanks, Skeeter! I've flown just about everything but helio-coptors! The 'old timers' are the most fun... so far!

[MarkRobbins]

Michael the building machine! I like the torsion springs you installed in the Nimbus I got from you! Good feature!

[ARUP]

Thanks, Mark! Just like the blind squirrel finding a nut every now and again I come up with an idea or two... It's funny but I put 'track bars' or Panhard rods on all of my WWI birds that had floating axles. I put this on a build thread for the world to see, especially with Dawn Patrols becoming more prevalent, and didn't get one comment about it. I thought it was a brilliant re-purpose of an old idea but what do I know!

[ARUP]

Here is the torsion spring epoxied and ready for action! The 'M' has a glass patch with epoxy over it as do the 'ears' on the doors.







More...

[ARUP]

Next order of business was to get the rudder servo and its acrutiments together. The rudder (and elevator) servo is in the tail of this model. I used a short Spectrum extension lead, cut it in half then soldered on an even longer extension between the ends. I made up two- one for the rudder and one for the elevator. They will reach the receiver in the cockpit easily. Next, the directions call out for you to mount a fiberglass G10 material 'tiller' to the servo wheel. The servo wheel had to be trimmed to fit the clevis each side without binding. The tiller was mounted to the servo with sheet metal screws then the screws had to be cut using a Dremel so that their ends wouldn't interfere with the servo case. The kit comes with the parts grouped in bags. This is very handy when working on a particular area of the build. The long white 'toothed' plastic/nylon hinge parts are used to mount the rudder.







That's as far as I am. More to come!

[Mark9]

What no labels on the bags? OOH, would be in German anyway, never mind.

[ARUP]

Thank goodness the bags of various items are grouped logically!

[ARUP]

The first snafu has arisen! The rudder servo is mounted inverted inside the fin, i.e., the tail wheel opening is the servo access. The G10 tiller has a hole in its center to access the servo arm screw. The G10 tiller is 28mm eye-to-eye and can't be any wider due to space constraints inside the fin. The rudder horns as designed are 40mm eye-to-eye. That geometry won't work if using both pushrods because it doesn't form the ideal parallelogram, Being a trapezoidal shape the pushrods connected to the rudder horn will essentially lock everything in place. I could work around it by making another 'bent' or boomerang shaped tiller but I like pull-pull cables better and this snafu gives me an excuse to install them! This will allow a little weight to be removed from the tail saving weight in the nose. So... I won't need the long extension lead previously made and the servo gets relocated forward. I tapped the rudder horn ball joint connectors to fit 4-40 threaded couplers. The rudder hinges and pin were set up, the receiving holes in the fin were cleaned up to fit the hinges then everything epoxied in place after test fitting.







The servo rails have been added to the fuselage. Once the epoxy cures the rudder servo and cables install will be shown. The rudder servo has to be clear of the centrally located wing mounting pin. Get ready for more!

[Asher Carmichael]

I like me some ASG29 ;-). Looking good, Michael. Should be a real performer.

[ARUP]

Howdy, Asher! This 29 is pretty! I've been looking at some trim schemes online but may just stick with stock stickers since no one around here has one.

[MarkRobbins]

I'd be willing to test fly this for you at SLED, Michael.

[ARUP]

Thanks, Mark. Deputy Dawg has one so we are getting together on it!

[ARUP]

The rudder servo was fitted with a longer tiller so it has eye-to-eye measurement of 40mm just like the rudder horns. The servo to rudder push rods shown in a prior post were re-purposed. One threaded end was cut off. The end was heated cherry red, hammered flat then drilled to receive a pull-pull cable. The cables were run and that is done! The elevator servo and set up is next. That'll be tomorrow.



Buenas noches!

[ARUP]

The elevator pushrod connections and CF pushrod were put together using epoxy. The servo end is an adjustable clevis with a lock nut. It was pretty much follow the enclosed directions... except... the ball link part would not thread onto the connector (hole too big) so I just epoxied it onto the CF rod directly instead of trimming the CF rod to fit the two threaded end pieces. Good thing I test fitted everything first! The ball link connector had to be bored out to fit the larger diameter CF rod. The ball portion of the ball link had to be fitted and epoxied to the elevator. A stone on a Dremel was used to make more clearance at the elevator where the link fit onto the ball. Again... lots of installation, test fitting, removal of parts, grinding, test fitting again. Is this what is called 'fettling'? A piece of scrap fuel tubing was used to hold the ball so it could be threaded into the elevator after the hole was tapped. When all things fettled to satisfaction they were finally assembled with epoxy. The mechanicals of the tail end are done! You can see the rudder hinge pin that allows its removal. The stab is held in place with two large whit nylon screws.







Bonne nuit!

[Mosquito]

Looking good Michael!

[ARUP]

Thanks, Tim!

[ARUP]

Mosquito Tim, aka, Deputy Dawg, clued me in about wing servo set ups. Spectrum 7050 thin wing servos are being used. The kit has centrally hinged wing control surfaces. The control surfaces at the servo locations are ~24mm thick so they rotate around an axis of 12mm radius. The servo mount from the bottom of the wing and drive flap and aileron pushrods to the upper surface. Test fitting these and full travel for the push rod one way is only 4mm. The horn protrudes from axis center line to be a length of 17mm. The kit horn eye is only 5mm above the surface of the control surface. Yikes! This might be okay for someone planning to fly sedately (like me) but if there is ever a case where excessive speed occurs then flutter might be an issue. New horns were made and they are 18mm above the control surface for a total arm length of 30mm. This should be more resistant to flutter all other things being equal. A longer horn won't pass through to the top of the wing like the kit item so these will be located on the bottom.

The spoiler servos can only be installed one way, that is, the output drive has to face toward the LE of the wing. One servo arm will be pointing toward the upper surface and the other will point toward the lower, if one wants a totally mechanical symmetrical spoiler function. To clear the servo horns one servo has to be elevated within the servo bay and the other has to be recessed within it. Here are a few pictures showing the spoiler and flap servo install. More pictures when done will, hopefully, provide a clearer view (pun?) of what is intended. This has been a real chore for someone used to antique birds!







The first pic shows spoiler servo elevated on mount blocks and the aileron servo on mounts blocks as well. The bay was scuffed and cleaned before using epoxy on the wood blocks. The second pic shows the marking of the flap so a slot can be cut to receive the new horn. The third and fourth pics show the paper pattern used so the recess can be cut into the servo bay for the other wing's spoiler servo. The wood blocks will get epoxied from below. That's where I am so stay tuned for the rest of the story!

[ARUP]

The flap and spoiler servo installation is done! The two pics show the differences. The third pic shows an empty aileron servo bay. These will be a piece of cake compared to the previous work.




Later, folks!