Jump to content
Playing in the Sandbox Group Build Sept 1, 2024 - Jn 1, 2025

1:24 Grumman F7F Tigercat N7654C


Recommended Posts

evening folks smile.png

 

..just a few quick snaps now the U/C is pretty much finished..

 

..added the gubbins to the retraction arm which must be part of the actuator - there is also a little junction box like thing that has a pipe coming out of it that runs along the arm and back up into the bay via the noseleg..

 

WIP731_zpsgdo7khgn.jpg

 

..added the actuator arm and taped up a spacer to protect it..

 

WIP732_zpsmrjsfcwt.jpg

 

..calling this done..

 

WIP733_zpscu78yt7a.jpg

 

WIP736_zpsqgnmxeun.jpg

 

WIP734_zpstynbrb1h.jpg

 

WIP735_zps1nmbhpsu.jpg

 

TTFN

Peter

Link to comment
Share on other sites

  • 3 weeks later...

evening folks :)
 
..thanks for stopping by..
 
so, it's engineering time - some serious structural work to sort out wing spars and mountings for the main undercarriage..
 
first I thought about how to mount the U/C in the wings - the answer was a chunky brass plate that also could be used to tie in the wing spars as one unit and allow me to slide them in and out of the stub spars while I build the wings..
 
..I clamped it all up and fearful of burning the whole thing to the ground soldered together with a torch - I put some metal clamps on the spars before they go inside the airframe as I hoped they would act as a heat sink and not cause any disturbance to the fuselage...
 
WIP792_zpszn9wqp9z.jpg
 
..cleaned up the joints and it is rock solid..
 
WIP793_zps1zwuztch.jpg
 
..made up the other side..
 
WIP794_zpsyomnxygh.jpg
 
WIP795_zpsahq8uojj.jpg
 
..the main gear leg is perpendicular to the spar, but is canted at an angle to the wing chord...it is also a solid leg until it gets in the nacelle then it is a mass of rods & arms. I can't model it like that, I need a rigid mounting so will have a mounting tube to slide the leg into...
 
WIP801_zpshssel41m.jpg
 
..the geometry is complicated so I mocked up a nacelle and the gear door openings (the cut-out at the front) with an old spray can lid so I could work out where to put the mount..
 
WIP796_zpssfmdennj.jpg
 
..I also don't trust my eye as the whole airframe has been built away from jigs or any kind of traditional keel so I hung the plan over my kitchen table and worked out where on the mounting plates the fittings should be by working from the wing leading edge so they are correctly positioned...
 
WIP797_zpsblc9miva.jpg
 
..and with some careful setting up was able to solder on the mounting lugs...
 
WIP798_zpseaurhbvd.jpg
 
..the structure seems to look ok and equal, and importantly if I balance it where the gear will be it is not a tail sitter (by quite some way) so the resin nose & lead weight worked...
 
WIP799_zps3brxbsor.jpg
 
..the 3mm card wing cores sit above these and have cutouts for the air intakes - I also made a wing root rib which along with a few more half ribs along the wing will be the points to sand the balsa down to to get the core right...
 
WIP800_zps2vgb2vts.jpg
 
..lots more to go, but it's a start...
 
TTFN
Peter

  • Like 1
Link to comment
Share on other sites

  • 1 month later...

evening folks :)

 

it's been a while and things have moved on a bit, so here is the latest on the big cat..

 

..I set myself goals to move through the stages needed to get a bird like this done - "make the nacelles, so you can skin the wing", "sort the landing gear geometry out so you can detail the nacelles", "skin the lower wings so you can build the nacelle internals" - I have to discipline myself to do these steps so there is some order to the approach and things don't clash with each other..

 

..the current goal is to get the lower wings skinned so I can get the nacelle structure built, so I thought as it is the lower wing just go for it in one big sheet..

 

..I marked out rivets, panels and use colours to tell myself whether to rivet from the back (so domed rivets) or stop points so I don't rivet through a panel etc.. restoration photos are great for this as you can see panel & rivet details - unfortunately it is much more difficult with a Dark Blue GSB F7F sitting in a hangar which is what most of my reference is - but I think this is near enough...

 

WIP959_zpslvzh8oqe.jpg

 

..then after at least an hour's work the panel is fully detailed - here is the template being peeled off..

 

WIP960_zpsro5phway.jpg

 

..I also masked and wire woolled the roof of the U/C bay as the litho plate has a sort of coating I am not sure will take paint, so I stripped it down & will metal prime it..

 

..I will be cheating as this will need to pretend to be the wing top skin, as I don't want to go chopping the wing about

 

WIP961_zpsokwylafj.jpg

 

..and fixed it in place..

 

WIP962_zpsriufspb7.jpg

 

WIP963_zps8g1ymwor.jpg

 

..another little challenge on some of the top wing skinning are some vents in what is the U/C bay roof - they literally are just holes I think to maybe let hot air created by the engine out of the U/C bay..

 

I cut some thin slits in the panel and tried making a shaped punch to indent them, after experimenting I had to make a female part to stop the vent mishaping or becoming too big - better to find that out on a test part than a panel you just spent time on..

 

WIP964_zpsj2qg4jpu.jpg

 

..they turned out ok though..

 

WIP965_zpsv931xo1p.jpg

 

..and thats it - stage complete - the undersides are done and I can start on the U/C bays...

 

WIP968_zps3sgp3kve.jpg

 

WIP967_zpsnjw0matn.jpg

 

..and to give a sense of scale, here it is with a 1/32 Sea Fury - the only other model I have completed since I re-started in 2010... ahem...

 

TTFN

 

Peter

Link to comment
Share on other sites

Peter,

Another epic update, you make it look so simple but then again so is math ( if you have a feeling for it).

Really looking forward to see it ( and you) at Telford. Perhaps your skills may lead me towards

Trying that scratchbuilt Hampden one day, as I don't see Tiggers's Models repairing the moulds.

Cees

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...