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Alpina - bad news / good news

Wayne said:
What are the blades made from?
Click to expand...
Whoops, I missed Muck's post. Anyway, as stated, they are made of Spring Steel.

More info:

Wiki:
Spring steel is a name given to a wide range of steels[1] used in the manufacture of different products, including swords, saw blades, springs and many more. These steels are generally low-alloy manganese, medium- or high-carbon steel with a very high yield strength. This allows objects made of spring steel to return to their original shape despite significant deflection or twisting.

Popular grades of 'rusty' spring steel are:
  • 1074/1075
  • 1095 (A684)
  • 5160 (A689)
  • 9255
Non-Rusty Stainless Steel.

Recently, there have been non-rusty stainless steel alternatives, but normally, these are only available in round-wire format. Its pretty unlikely that these can be found in flat rectangular format, but for info: :
  • 301 (A666) Spring tempered stainless steel
  • 304 " " " "
  • 302 " " " "
  • 316 " " " "
  • 17-7 (ASTM A-313).
Doc.
 
This Alpina kit was missing the OEM joiners so I sourced appropriate sized joiner material on eBay. Specifically I have CS95 carbon steel joiners
 
1st time I’ve re-inserted the wings since the accident. Interesting - only the left joiner got bent. The pinch bolt in the joiner box probably pinches the [front] right joiner blade tighter than the [back] left joiner blade , which would allow the left wing to get yanked out / pivot forward at a lower threshold. Also further explains why the left/right asymmetry in fuselage damage is the duplicated on other people’s crash pics.
IMG_7795.jpeg


Update: Well… that was easy!
IMG_7797.jpeg
 
Last edited:
Last patches have been applied. Got the fuselage wing root LE area back to a close-enough match to the wing. Kinda went by feel to determine where the edges of the low spots were and marked them with the sharpie to help guide the application of glass cloth.
IMG_7798.jpeg
IMG_7803.jpeg
IMG_7804.jpeg
 
The end is in sight! Re-installed the left side anti-crush brace socket after roughening up the mating surfaces.
IMG_7808.jpeg

A quick shot of white primer to see where I’m at on surface shape. Looks like I’m pretty close.
IMG_7810.jpeg
 
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