1/3 scale Japanese vintage glider Mita type 3

Let us all watch your new project progress.
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norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 27 Nov 2019, 05:20

VinceC and Jolly Roger, Thank you for your comments.

Jolly, I used the carbon powder available from retailer and mixed it with epoxy glue. Although it is named "powder", it contains small carbon fibers and if you mix it with epoxy glue it becomes CFRP. It is very tough and light. Weight of the completed basic fuselage I posted yesterday is only 710g nevertheless its length is over 2m. It is very rigid too.

Carbon pipes are jointed with a short piano wire inserted and glued by epoxy where possible, but most joints are just epoxy bonded only. Those joints that seem to be important are bonded with a small carbon plate for reinforcement. The wing support beams are tied up with the longerones by carbon threads and glued. Please see attatched pictures.
Attachments
Carbon powder.png
Carbon Powder
Epoxy bonding.png
Bonded joint close-up
Joints with small carbon plate.png
Joints with small carbon plate
Wing Support Beams.png
Tied up wing support beam
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norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 27 Nov 2019, 12:00

Tail Wing Mounting brackets, Tail Skid and the Elevator Bell crank
The horizontal stabilizer is mounted with three M3 bolts through carbon pipes placed on the AFT fuselage. The vertical stabilizer is mounted at the end of the fuselage with two M3 bolts.

The real Mita's tail skid is made of three ply of steel plates with an abrasive shoe. In my model it is made of carbon plates with an alminum shoe. These plates are not bonded each other for the maximum spring effect.

A bell crank made of carbon plate/pipe is equipped under the horizontal stabilizer which is connected with the elevator.
Attachments
Tail Installation Plan.png
Tail Parts Installation DWG
Tail Wings Attachments.png
Tail wings mounting brackets
Tail Wings attached.png
Tail wings Installed
Tail skid and Elevator Bell crank.png
Tail Skid and Bell Crank
Elevator control Linkage.png
Skid and Bell Crank Installed
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Peter Balcombe
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by Peter Balcombe » 27 Nov 2019, 12:31

Norm,
How did you cut the bellcrank plates?
Are they all made by hand, or do you have CNC cutting facilities?
Very good work anyway :)

norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 27 Nov 2019, 12:54

Peter, I cut them by hand with a mini router which has a diamond saw. Then they were trimmed by a diamond file.
Attachments
Mini router with a diamond saw.png
Mini router
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norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 28 Nov 2019, 02:34

Fuselage sub structures
The Mita's fuselage has sub structures around its rectangular main structure, the lower sub-structure, the upper sub-structure and the side beams. With these sub structures its cross section forms octagon when coverd with fabric. Both the upper and lower sub-structures are made of carbon pipes and the side beams are made of paulownia plates.
Attachments
Making the understructure.png
Making lower sub-structure
Understructure completed.png
Lower sub-structurer
AFT Fuselage upper structure.png
Upper sub-structure
Side Beams Installed.png
Side beams added
Side beam.png
Side beam
Fuselage cross section.png
Fuselage cross sections
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norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 29 Nov 2019, 06:59

Motor mount
This time I will show you the motor mount.

Why Motor? This may be a common question of the European scale glider fans. First of all I must explain the Japanese scale soaring enviroment. Japan consists of innumerable islands, lage and small, of which four islands are relatively large and most people live there. Total area of Japan is about 370 thosands square km. It is a little bit larger than Germany but, in contrast to Germany, its 70% area is mountainous and 2/3 are covered with forests. On these islads there live more than 120 million people. So there remain little spaces for model glider flying. Because of these enviroments, it is not common to use a tag or a winch that requires somehow a large space. It is common to install a motor and a foldable prop. By the way, because of limitted space, 1/5 scale models are called big and 1/3 scales are extra-big in Japan.

The motor mount of my model extends forward from the main fuselage and requires a special jig to build it correctly. The motor is mounted on a plate made of 9 mm thickness plywood. This plate is supported by carbon pipes and plates. A plywood plate is bonded on the upper side on which the ESC and a battery for the receiver will be installed later. The motor is FUTABA FMA-5065 KV300, 2000W class motor.
Attachments
Motor Mount Plan.png
Motor mount Plan
Jig for Mount ASSY.png
The Jig
Making Mount.png
Making Mount
Mount Completed.png
Completed Mount
Mount with a Motor.png
Mount with the Motor
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norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 30 Nov 2019, 06:18

Tow Release
There are two tow release equipments in the original Mita, for the aerotow and for the winchtow. The former is at nose and the latter is in front of the landing gear. I have no tag nor winch but I made these equipments for the model. They are not dummy but really work. These are hand made with aluminum plate. One servo actuates both. As the elevator control tubes pass through the center of fuselage, the winch tow release is attached on the port.
Attachments
Winch tow release plan.png
Winch Tow Release plan
AeroTow release Plan.png
Aero Tow Release Plan
Winch Tow release Parts.jpg
Winch Tow Release Parts
Winch tow release.png
Winch Tow Release ASSY
Aerotow Release.png
Aero TOw Release ASSY
Winch Tow Release Inst.png
Winch Tow Release Instalation
Aerotow Release1.png
Aero Tow Release Instalation
Winch Tow Release test.png
Winch Tow Release Test
Aerotow Release test.png
Aero Tow Release Test
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Cliff Evans
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by Cliff Evans » 30 Nov 2019, 07:03

Spectacular detail Norm.

norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 01 Dec 2019, 10:00

Pilot Seats
The original Mita's pilot seats are composed of a curved wood seat, steel pipe legs and a fabric seat back. Top side of the fabric seat back is wrapped around an aluminum tube and this tube can be moved back and forth for requilining by changing two pins that fasten the tube with the fuselage structure. I simulated them with a curved plywood seat, bamboo rods legs and a fabric back. The aluminum tube is simulated with a balsa rod.
Attachments
Pilot seats Plan.png
Pilot seats DWG -side view
Pilot seats Plan2.png
Pilot seats DWG -top view
Pilot seats.png
Seats
Pilot seats Instaled.png
Seats and Back
Pilot seats Instaled2.png
Top view of the Seats
Top View.png
Requilining bar
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norm
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm » 02 Dec 2019, 13:27

Landing Gear Cover
To prevent air comes in fuselage through the gap around the landing gear, there are two kinds of covers. One is a wheel cover made of plastics and the other is a seal made of fabric. For my model I made the wheel cover with plywood and balsa and the seal with fabric.
Attachments
Landing Gear Cover DWG.png
DWG
Wheel Cover.png
Wheel Cover
Gap seal.png
Gap seal
From the Inside.png
View from inside
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