• Administrator
  •  
    Before your membership becomes valid, you will receive an email that must be answered.
    Please check your spam folder or this email.
     

Scratch built Pilatus B4 to 1/4 scale.

Let us all watch your new project progress.
B Sharp

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by B Sharp »

I really don't need another 3gm at the tail end Rog!
Brian :oops:
User avatar
VinceC
Site Admin
Posts: 613
Joined: 22 Feb 2015, 11:45
Contact:

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by VinceC »

Signs of old age creeping up. Don't worry as it only gets worse
User avatar
RobbieB
Posts: 547
Joined: 07 Mar 2015, 22:22
Location: North West

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by RobbieB »

:lol:
B Sharp

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by B Sharp »

In the last few days I have tackled the wing roots and fairings of the fuselage. My workshop is not large enough to have both wings attached to the fuselage and still have room to work round about it so proceedings were transferred to the dining room table (with the kind permission of Mrs S).
The airframe was assembled with the wings resting on two large boxes and the fuselage hanging between. An incidence meter was attached to wings and tailplane and this showed a decalage angle of 2.2 degrees (quick nod to Antonia) which will do quite nicely thank you. Once fuselage, wings and tailplane were all squared up the inner wing root ribs were attached to the fuselage with epoxy and thin ply forms. Once disassembled and back in the workshop the gaps between the ribs and the fuselage were blocked in with balsa then covered in “Epol” filler before lots of careful sanding. I am quite pleased with the finished result. :) :) :)
The next job will be to wet and dry the glass on the whole fuselage and then the wings – not a job I am looking forward to.
Brian. :?
Attachments
Wing roots during set-up.
Wing roots during set-up.
The finish product.
The finish product.
Jolly Roger
Posts: 573
Joined: 30 May 2015, 20:35
Location: Sutton Bank, North Yorkshire

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by Jolly Roger »

Looks really smart Brian. What's your wing joiner?
B Sharp

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by B Sharp »

Hi Rog. It's a 14mm carbon rod in 16mm carbon tube. This should be more than man enough for a 1/4 scale model, even taking into account my occasional hooligan episodes.
Brian. :)
Jolly Roger
Posts: 573
Joined: 30 May 2015, 20:35
Location: Sutton Bank, North Yorkshire

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by Jolly Roger »

B Sharp wrote: 10 Jun 2020, 17:36 Hi Rog. It's a 14mm carbon rod in 16mm carbon tube. This should be more than man enough for a 1/4 scale model, even taking into account my occasional hooligan episodes.
Brian. :)
Yeah, that should do the job! I found it impossible to break a 12mm carbon rod in a 5kg, 4m model by aerobatics alone. I needed a hillside to do the job properly. ;)

So you should have a decent margin. In theory a 14mm rod is nearly 60% stronger than a 12mm rod, as section modulus goes up with the cube of diameter.
B Sharp

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by B Sharp »

Rog, section modulus is a term I haven't heard or used since my early 20s and at college.
Brian. :)
B Sharp

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by B Sharp »

I’ve been focusing on some of the fiddly bits today. I started with the canopy frame as I am expecting to get my newly pulled canopy mouldings back from Barry at Sarik in the next few days. It’s constructed from 3.5mm ply, held in place at the front with a 6mm dowel and at the rear with 4 x 10mm button magnets. The instrument binnacle has been shaped with balsa block and has then had 0.7mm plasticard wrapped round the shape to give a good flat surface and a slight overhang to the instrument panel.
I have started on the undercarriage doors by bending a piece of 1.0mm aluminium sheet round a form to achieve the curve of the bottom of the fuselage. I have created lips inside the fuselage front and rear of the opening so that the ali sheet sits flush with the fuselage surface. Once I have formed the hinge seats inside the fuselage I will cut the ali sheet in half to create the two doors.
Brian. :) :)
Attachments
Cockpit frame in place.
Cockpit frame in place.
Undercarriage doors during fitting process.
Undercarriage doors during fitting process.
User avatar
Peter Balcombe
Posts: 1399
Joined: 18 Mar 2015, 10:13
Location: Clevedon, North Somerset, U.K.

Re: Scratch built Pilatus B4 to 1/4 scale.

Post by Peter Balcombe »

Very nice Brian :)
Post Reply