Tuesday, October 12, 2010

Frame 10

Frame 10 is another major frame as it holds the attachment brackets for the rear wing spar brackets.It consists of a double frame of U shape and sits under the pilots seat.Material is aluminium of 1.2mm thick.The buttstrap used to connect the webs is the same as Frame8,s although rivet size has grown from 1/8th" to 5/32nd".

Also where the bottom cutouts are for the longeron there are stiffening doublers that differed from early to late Mk Spitfires.Internally is the same spacer arrangment as F8 although at the bottom corners there are U Brackets to help distribute the loads of the wing spar brackets.At the top corners of the port side are holes for fairleads to take the rudder and elevator trim cables.

Sunday, September 19, 2010

Frame 9 and control box

Frame 9 sits just in front of the pilots seat and is fairly complicated as it is the centre structure for the Spitfires control column and rudderpedal assembly.
The assembly consists of three hatsections,one at the bottom and the other two for the port,starboard vertical members.These are 1.5" x 1.5" width and height with a .6" flange out of 20guage aluminium.The tricky part is that the section is twisted slightly due to the curvature of the Spitfires fuselage at that point.
This assembly is diagonally braced with "squared off round tube" of 1"x1"x .036".At the centre are two vertical channels.These are to provide strength for the aileron control drum mounting.Further out are two more channels.These hold a spherical,self centering bearing for the rudder bar slides to move through.
The control box starts at Frame 7 and continues through to Frame9 at its rear using diaghragm members and bracing of 1" and 3/4" square tube.At the front the assembly holds the Spitfires rudderbar which pivots on plates mounted off the F7 diaghrams and longditudal bracing for the pilots heelboards.Just behind F8 sits the second set of diaghrams and bracing of which the pilots control column sits.This pivots in two blocks mounted on the bracing assembly..

Tuesday, July 27, 2010

Frame 8

Update time again.This is Frame 8 which every Spit lover will know as the one below the instrument panel.Actually the instrument panel sits back a bit from the aft edge of frame 8 by about 40mm.
The frame is in 4 main sections,port forward,port aft,starboard forward and starboard aft,These are joined together by buttstraps at the bottom and the compass mount plate at the top.Joining fwd to aft is by c channel brackets that radiate around the frame and by a coaming that wraps around the internal shape.At the top is a capping strip where the Blind Flying panel mounts bolt to.On the webs are the kigass primer,fuel tank selector and pulleys for the Uc locking cables.On the forward side up top is the bracket for the fuel tank bracing tubes.The compass bracket also bolts up and is offset to one side.Think this is to give a pilot a better look as the control column would block the view.At the bottom is the diaphragm attachments for the control column and rudderbar heel assembly.

Monday, June 7, 2010


Next frame back is frame 7 which is the rearmost support for the bottom fuel tank.Virtually the same type of frame as per 6 but a bit deeper due to the drop in the fuselage profile.The top curve is exactly the same as frame 6 due to the mounting of said fuel tank.Also this is the start of the Spitfires cockpit as the diafragms for the rudderbar bracing start here.Just behind frame7 is the cockpit front fireproof bulkhead.A 3D design of the frame and placeholder bottom fuel tank to see if it here...all will fit.

Wednesday, May 19, 2010

frame 6

Working back is the start of the front fuel tank area.Here we have the first frame which is frame6.This is a web at the bottom along with hatsection side members that terminate at the datum longeron.The top curve of the web matches the profile of the bottom skin of the bottom fuel tank.Triangular gussets strengthen the web.

Friday, April 9, 2010

Anatomy of the Spitfire

Starting with Frame5 which is the Spitfires engine firewall assembly and wing front attachment point.The lower assembly is made up of a front and rear web,spaced out with aluminium spacers and C section brackets.On the front and back are the wing main spar attach spars.There are two upper and two lower spars.
Up the top is the engine firewall which is a sandwich of two thin sheets of .022" aluminium and a 3mm sheet of asbestos or fireproof board..Mounted to the firewall are the various parts and brackets like the hydraulic tank,filters and other fittings for the Merlin.

Tuesday, March 23, 2010

Winging it

One of the most amazing structures or frustrating is the Spitfires wing.A genius of his time,Mitchell created an engineering marvel.This is due to the complexities of it,s internal structure,from it,s D section leading edge to it,s different main spar fabrication.Today a man I think who is doing some marvelous work reverse engineering the wing is Justin Adams from Europe.Working off original drawings,especially the Supermarine drawing for the chord offsets and reverse engineering an original wing Justin is slowly creating a 3D model of the wing and it,s internals.He is using a design program called Rhino and here are some screenshots of his work so far..

Friday, March 19, 2010

Up the front...

Another set of WIP pics this time by a friend in Japan named Fumiyuki (Aka Shinpachi).He works in a brilliant 3D program called "Shade".This is to recreate a Rolls Royce Merlin for the project in different ways.all the work has been researched off various factory manuals,photos and some original drawings.Pics shown are the bottom end and some of the top end.

Tuesday, March 9, 2010

Start off.

Here is some beautiful Solidworks screenshots done by good friend Tony and his students at John Swett High School Cad Class at Crockett,California USA.
His work is a conjunction using the Morningford MkIX book and original Supermarine Drawings..

Thursday, February 11, 2010


Well this is sort of new to me but starting off a project like this is something I,ve been wanting to do for a while.Well you all know of the Reproduction Spitfire we are building but this blog is for the designwork going into the project.
This is not a reimagined,or teched up/modernised Spitfire.This is as faithful as we can get it to Mitchells genius as we can get.All measurements,shapes,materials are Spitfire down as close as we can get it.Tracing is being used in some instances but all scaled off known measurements.
Things will go through gradual updating as more info comes aboard as parts become available.The problem..I doubt of the odd 22,000 Spitfires built that any two are the same..Why?Even though they came off an assembly line everyone of them was virtually a handbuilt creation.Oh yes some jigs were used but the majoritory of the structure was drilled off the part next to it.Also having multiple factories using multiple subcontractors added to the problem.
So the idea is to try 'Standardise" a Spitfire in 3D using the worlds design software.These include CAD,ProDesktop,Solidworks,Shade,Rhino and maybe a couple of others.
All in all this will be a showcase of as much of the internals of the Spitfire as we can get.And no I am not alone.There are quite a few guys that I will try get (blackmail,bribe,beg) to contribute to the cause..
Till I get all the screenies sorted..Here,s to a wonderful dream of having these girls flying forever..