Tuesday, 31 December 2013

Hes not the Messiah,hes just a very naughty boy..

Hello,hello,this thing on?.....Ok here we go.Welcome to the new blog for the Spitfire MkVc-Trop A58-27 blah blah blah project:)
A lot of you guys are probably wondering (pointy fingers) if the project is still going?The answer is a yes most definitely.Like a Hydra you cut off one head(me) another one grows..Well to be honest I cut myself off for sanity reasons of a personal nature.I,m still here,a bit wiser and a lot more relaxed..Just not as close to the project geographically as I was once was so I now have a latitude of freedom of what I can do and when I can attend..Ok enough about me (riiiiight)..
Firstly I must congratulate the guys who continued on with the Spit,as all major undertakings it has taken on a life of its own now and is growing both physically and spiritually.
A lot has gone on in the last two years physically with the skeleton now almost complete with only a few odds and ends to bolt in before skinning can commence.Well how did this happen?
If you took your skin and muscle off you are built up of bones (please do not do that).A semi monocoque  aircraft is the same with many big bones joined together with little bones.The big bones are the frames which we stripped off the plastic,sent off to the guys at Amberly AFB to be heat treated and straightened.This involves putting the frames in a big oven and bringing the aluminium up to a set temp for a set amount of time and then removed and rapidly quenched in water.This shocks the aluminium so some twisting is involved so you have 20 minutes to place to frames back into their formers and clamped down before the grains realign themselves and settle resulting in straight frames again.
Back to the workshop it took us half a day to prime up the frames and reinstall in the jig,then using our preassembled intercostals and brackets, skin pinned the whole thing together.A quick go over with the laser level (measure,measure,measure) brings things into alignment ready for rivetting work..honestly it was riveting.A lot of riveting.....On average 11 intercostals between each frame with brackets either end (all different angles) with 7 rivets per bracket,3 on intercostal and 4 on frame.
Next are the Longerons to go on with the spine going on first.This a V section longeron with shaped brackets that tie the frames to the spine.These were all mass produced by hammerforming and then trimmed etc for angles and lengths.Primed,riveted together in pairs they were drilled off and installed on the back edge of each frame.Between F12 and F14 the Longeron assembly changes due to the Antenna mast going up through the middle of it.The designers came up with forming 2 channels of C section and bending/twisting them to suit the curve of the fuselage.This was achieved by marking out a lofting board of bends etc then forming the channel to suit.With these cleaned up and primed straps and brackets tie it all together.A sheet of paper was placed over the skeleton at this area to see if there were any gaps or odd bumps and lumps which would show up with skinning.
The spine longeron was placed in position and then measuring back for each Frame to Frame station the brackets were located and drilled off..To get best fit a sheetmetal strap was clamped over the longeron to achieve positive location.
So drill drill drill,deburr deburr deburr,rivet,rivet,rivet the spine was now installed.
Looking further down is the datum longeron which is split into front and rear halves,the aft half being tapered back to F14 where intercostals take over.
The overlap of the halves requires an offset of surfaces so a joggling (like a juggle but different) is required to bring a continuation of surfaces for the skin to rivet to..Also the back section from F11 aft is curved (wouldn,t be a spitty) so a set of pressing dies are made of hardwood.
Prime,drill off,deburr and rivet :)
Last major parts to go on are the bottom longerons which are of a W section.These are tied in using multiple small angles to the frames.These are pulled in tight to the frames by straps and drilled off,deburred,primed and riveted on..
Oh shit we forgot the end bit... Hmmm now this is tricky as the tail separation point is not vertical but sits 8 degrees off laying back at the top..Lucky with some maffmati,methmat,mathme,mathmetics all the measurements and angles worked out to locate and fabricate the rear jig position.This allows us to tie all the structure back from the tail to F18 as a half frame F18A hangs a bit in midair only tying into an intercostal on its bottom edge..
So what else goes into a spit skeleton?Structurally not much but the designers decided they need somewhere to put a radio (apparently two tin cans and string wouldn,t work) so this is in the process of being fabricated and assembled ready for assembly..
So much said so far..Any questions please annoy me anytime,especially if your female,single and hot looking :0


  1. Good stuff Ross, glad to see you're still at it!

  2. Nice stuff! I am looking for drawings for the pilots seat. Do you have a source for some or can I get a copy from you? Thank you- Cheers