Page 5 of 5

Re: MU13 Charlesworth

Posted: 02 Sep 2019, 15:36
by Ben Matu
Thank you for the link. I know that there is a lot of work. I dont want to built full scale. It will be my first old lady.

Re: MU13 Charlesworth

Posted: 27 Oct 2019, 22:53
by John Vella
At last the finishing begins. The fuselage top is skinned in .4 mm ply to blend in with the wings. The cockpit and canopy are painted in flat sky grey acrylic. The rudder push pull system is installed via an indirect 180 deg bellcrank drive. Elevator control is via a carbon push rod to a brass elevator control horn. Access is through a slot in the rear balsa floor. The tailplane is mounted on a balsa seat with steel front pins and a 4M nylon bolt into a captive nut. The fin is attached with a ply tongue located in a ply box and at the rear post a 1mm steel pin mounted in brass tubing.
The diagonal upright into former 7 is supported by a balsa fillet which helps blending the covering at the angle change in that area. The transition under the fuselage wing seat aft from the 0.8mm ply at former 6 is a thin balsa fillet. The covering is in Oratex which works well on compound curves.
The final rigging check is done with wings and fuselage in the garden. The covered empenage are rigged and checked for alignment. The fuselage is covered in four sections with all overlaps going downwards. The radio and servos are fitted and checked. The three servos in the fuselage are Hitec 645mgs.

Re: MU13 Charlesworth

Posted: 28 Oct 2019, 12:25
by John Vella
Thanks Cliff, as you say not to far away to completion. A slow build hopefully gives time to get it right. None of these so called "professional " builds for me. Regards John.

Re: MU13 Charlesworth

Posted: 19 Nov 2019, 23:05
by FlyboyDave
Hi John, looks like the MU is coming along nicely :-)

Re: MU13 Charlesworth

Posted: 13 Dec 2019, 17:10
by John Vella
So after a few issues the covering of the airframe is complete . I had a problem requiring the reskinning of the top rear
Inboard ply skins of both wings. However with some heat the skins peeled back more or less intact. Covering in ORATEX was very straight forward with plenty of shrinkage around the compound curves. BALSALOC was only required on certain edges. The flying control set up was next. The ailerons set with 2 to 1 differential, 10mm down to 20mm up at root T.E. The elevators 25mm up and 20mm down. The carbon push rod is very stiff and so is unsupported from servo under the wing to the elevator horn. The rudder has a lot of movement, about 25 deg each way on a push pull cable system. A spring steel skid completes the back end. I guess that the main wheel being infront of the C of G unlike the K8 will mean the skid will get a hammering. The air brakes were the next job. ScalePolice please note that only the top operating DFS brakes are functioning as the bottom moving back paddles would be vulnerable to out landing on heather etc. The letter box openings are lined with 3mm sq spruce. The arms and side hinge frames are from 2.5mm glass fibre board. The hinge sides are joined by 3mm ply and 2mm steel pins used.the assemblies are fitted and glued to the skins upto the 3mm spruce strips between the letter box and the rear spar. The slots in the skins accommodate about 70 deg movement.the brakes are made from 6mm hard balsa sheet covered by 0.4mm ply skins. 3mm ply reinforcement mounts are inserted for the plastic horn mountings. The airframe needs a rig check when the weather allows. Regards John.

Re: MU13 Charlesworth

Posted: 14 Dec 2019, 10:22
by John Vella
Thanks Cliff, yes an NSFK colour scheme circa 1943 . I Hope to have it as a Munich area glider with the "Flying Man" on the nose. Regards John.

Re: MU13 Charlesworth

Posted: 26 Feb 2020, 12:04
by John Vella
Hi, due to a short illness and bereavement in the family the modelling has come to a tempory halt. Here are the last set of pics taken of the build. The pilot is a Pete's pilot on loan from my Charlesworth K8. Regards John.