Grumman AA5 Traveler Project 5

[lastvautour]

Excellent so far. This will make a fine quintuplet.

Lou

[Gearup]

Thanks Lou. The goal is to get all five glued up this week.
Fraser

[Gearup]

Wings and tail glued.

[Gearup]

rough filler applied. Some of the tools visible include a small trowel shaped dental tool that works great in tight corners. The big end is about 1/16" across and the small end is probably 1/32'.

[Gearup]

Major filling is pretty much done. I've been working on inlets and the ventral fin. The AA5 Traveler has a different cowl nose and a ventral fin compared with the later Tiger and Cheetah. The tail surfaces are really tiny on the aircraft and it probably needed more lateral stability so it had a small ventral fin attached. 

I carved out the cooling inlets firs. Then I added the chin on the cowl that forms the carb inlet and carved the carb inlet. 

I used my clamp to hold the model for gluing the parts on. I'll also use the clamp to hold it while installing the gear when the time comes.

[lastvautour]

Excellent so far. Much more detailed than my stuff.

Lou

[Gearup]

Thank you Lou.  The beauty of solid models is the opportunity for the builder to detail the model to their liking. To include more or less detail is part of the process. All of the models on SMM are testaments to the research, skill and imagination of the builder. If something is missing, the minds eye will fill it in if needed. 

The last line can actually be a problem if something needed to be there for other reasons than aesthetics....like four bolts in a door plug installation. 😳

[lastvautour]

So true.

Lou

[Gearup]

A bit more progress on the AA5.

Something was off about the lower cowl. Had to do a rework with a bit of filler, but it is on track now.

I discovered the shape was wrong as I was giving attention to the landing gear installation.

I have built up all three gears for the airplane. The Grumman series has both a rather simple and advanced landing gear system. The main gear legs are laminated fibreglass and are mounted into an aluminium fitting that is bolted the main spar center section. Th axel on the opposite end is also a fitting bolted to the outboard end. 

It is amazingly light and can take a very hard landing without damage. I once watched a fellow land hard enough that the top of the main tire almost contacted the lower wing skin. Ouch! There was no damage to the gear or aircraft.

The nose gear is more like a shopping cart castor on a stick. It is a spring steel strut attached to a torque tube mounted to the firewall. Most of the up/down load is absorbed by the torque tube.  The mount for the wheel is just that...a castor with no steering input. Direction control is accomplished by differential brake action on the mains. it's very effective at low speeds and above 20 kts or so the rudder becomes effective. When parking the airplane, you can apply one brake fully "on" and the aircraft will pivot around with the nose gear swivelling hard over.  The nose gear is prone to shimmy on landing if the adjustment of the belville (cupped) washers are not correct.

To construct the mains I started with .025" brass sheet 1/8" wide and tapered to the wheel end to about .1" wide. I drilled two 0.020" holes, one for the mounting pin the other for the axel. Using a flat pair of pliers i gave each end a 45 degree bend.  I then soldered .020"  brass pins through the holes and left them long for further adjustment.

The nose gear used 1/16' rod bent to shape. the nose castor was made using 1/8" square brass tubing wth the top and bottom sanded down to a taper. This also makes the square tube turn into a nicely spaced "U" with the end still a complete square. A 1/16" hole was drilled to accept the strut and then soldered to the strut. A bit of sanding and some filler to close the open end finished to off.

I'll now have get to locating them on the airplane.

[lastvautour]

Beyond my skill level. Excellent undercarriage.

Lou

[Boomerang]

 Excellent work!

 Gordon