Manxman (oz14562)

About this Plan

Manxman. Radio control sport aerobatic model.

Quote: "Manxman. Build from our free pull-out plan your own version of Dr Frederick Knox's 49 in low-wing sports model for a .40 size engine.

The Manxman is a small, quick responding low wing sport plane which is easy and quick to build at a low cost. The original was built for about £20.00, including wheels, tank, engine mount and Solarfilm. The thick wing, large radius leading edge and washout make for a gentle, predictable stall, good low speed characteristics and general good manners. It is reasonably fast, quite aerobatic and handles windy conditions well.

Tail first: The fin is, of course, built integrally with the fuselage. The tailplane and elevators are cut from hard 1/8 balsa sheet and the elevators are joined with a piece of 3/16 dowel, which is then sanded on top and below to blend in with the 1/8 sheet of the elevators.

When using 1/8 control surfaces, I prefer to make control horns from 1/16 ply which are then epoxied into a slot cut into the balsa. Some thin CA glue can then be applied to the balsa around the join, which also toughens up the wood. The surface of the horn then receives a thin smear of epoxy to make a strong set-up; stronger, I think, than the bolt through nylon type. However, this latter type can be used, in which case a plate of 1/32 ply should be glued to each side of the surface, as shown on the plan.

Fuselage: The sides are cut from 1/8 ply. This is quite easily cut with a hobby knife, using a steel straight edge and making several firm cuts. Lite-ply can be substituted, or, for those who prefer balsa, that's alright too. If 1/8 balsa is used, a 1/16 ply doubler from F1 to just behind F4 will be needed. No doublers are needed with the plywood sides, apart from a 1/8 balsa wing saddle to provide a wider seat for the wing.

In this part of the world (Canada), they build houses by the hundred and throw out enormous quantities of wood, including plywood of all thicknesses. The firewall was cut from such a piece of 1/4 in plywood which was sanded and coated with 5 minute epoxy on both sides after drilling for the motor mount, fuel lines and throttle wire. As motor installation varies according to the motor used, no specific one is shown on the plan. A commercial mount is used for side mounting the engine. F1, F2 and F4 are epoxied to one fuselage side, using a square on each one. When dry, the other side is epoxied to the formers, squaring everything in the process. 3/8 triangular stock is added at the firewall. F2a should be drilled for the 3/16 dowel before gluing it to F2. The sides are then pulled in at the tail and glued to each other, being very careful to get them true. The 1/4 sq spacers are added as shown, to stiffen the fuselage. Bolt on the motor mount and fit an 8 ounce tank and the fuel lines, as this is quite a close fit and can't easily be done later. Fit F3 and its two triangular braces.

The front deck is either planked with 1/8 x 3/8 balsa strips, or a single sheet if you are feeling brave. Actually, if 4 in wide soft balsa is used, and is kept wet on the outside, it isn't too onerous a job. Thick CA glue works well here. The rear sheeting is prepared by cutting the fin outline from 1/8 balsa and edge gluing to the lower sheet (note that this extends from F5 back; the side sheeting in the cockpit area between the front deck sheet and F5 is done as a separate piece) which is trimmed after it has been installed. F5, F6 and F7 are next to be fitted and then the tailplane is epoxied to the fuselage. This is a somewhat critical phase and needs care to get it aligned with the fueelage so that the fin will be vertical to it after the next stage..."

Manxman plan/article from RCM&E, September 1994.

Direct submission to Outerzone.

Supplementary file notes

Article pages, thanks to RFJ.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction