Vintage Fireball Rebuild

[treefoil]

This old Jim Walker Fireball from my Dad's youth had survived to a degree in his basement and then hung on the wall of my garage until this fall. I'll be rebuilding it from plans i found here so am very appreciative about that. I'll be receiving full size plans from American Junior Classics along with a canopy and decals. Dave

[gossie]

This old Jim Walker Fireball from my Dad's youth had survived to a degree in his basement and then hung on the wall of my garage until this fall. I'll be rebuilding it from plans i found here so am very appreciative about that. I'll be receiving full size plans from American Junior Classics along with a canopy and decals. Dave

Congrats......Pics as you do it please.

[OZPAF]

That's a great idea - good luck with it.

John

[treefoil]

Some 1/8" parts rough cut. Ribs and tail feathers. Wing bottom 1/16" balsa. Scaled rib and wing pattern. I'm chuckling a bit. I'll have most of the cutting and building done by the time I get the full size plans. Dave

edit. old wing section also shown that was left inside fuse.

[treefoil]

Interesting construction...ribs on a solid balsa skin. Nothing else. It'll be a bit of a challenge getting the top skin on while leaving the wing straight. There is quite a bit of flex in it as is. 2 1/4" dihedral at each wingtip. Four original inboard ribs were used. Dave

[OZPAF]

That was quite common back then. Lots of pins needed when gluing the top sheeting on I think I would use PVA or Aliphatic due to the lower drying time.

John

[treefoil]

Thanks John...I like the PVA suggestion. Here are the original build instructions and diagram for covering the wing. Seems there's a a 1/4" twist built into the wing at the outside leading edge. Also the top skin goes on in two steps. Magazines and the kit box are involved....love it. Dave

[OZPAF]

Fascinating old techniques! You would want to keep the kit box in good shape to use it for construction The magazine idea is still used and is a good way to spread weight.

The 2 stage gluing of the wing skin I believe was done due to the fast drying glue - similar to Ambroid, that would have most likely been used then. Although the 2 stage gluing is not really necessary with a slower drying glue such as PVA or Titebond, it could give you more control when attaching the top skin. However I would consider lining up the sheet at the LE and gluing it to the ribs and bottom sheeting only, first - holding it in place with masking tape strips with the wing weighted down flat on the board. When dry the top skin could then be glued to the ribs and weights (magazines - etc) and tape on the TE. You would need to be very careful to keep the wing flat any warp will be there forever. definitely don't do this on top of the kit box

The 1/4" wash in on the left wing is an interesting way to allow for the reduced lift on the inboard wing - assuming the model is flying in an anti clockwise direction. I would leave that out and build both wings flat and add a bit of tip weight to the bottom of the outboard(right wing). It would only need to be about 1/2 oz or so. The effect of the wash in will vary with speed where as the tip weight will not, and is the accepted approach now.

Good luck and Merry Christmas

John

[Balsa Ace]

Great restoration project,Dave.

Scott

[Big G]

I visited the Toledo RC Symposium in I think 1978, and there was a guy with a stall who was displaying and selling nothing but Fireball kits and finished models. As I always liked the look of the Fireball I got talking to the stall-holder and had a good look at what I took to be an original Fireball kit, the one that didn't have the bubble canopy. I'm sure it had a solid balsa wing, machined to airfoil section. I was impressed with the overall quality of the wood and the kit itself, given its manufacture date of about 1943. Strange how the Americans could produce such an elegant CL model when our first shot was the plug-ugly Voetsak.......

G