BC12 wing main spar

[taylorukuk]

Hi
We have 4 wings for our BC12 restoration and are trying to make 2 good ones from the wings we have.

However - On 2 of the wings the ribs have been attached to the spar with what looks like woodscrews?

Was this ever an option or is it a result of a botched restoration attempt?

BR Ian

[Hank Jarrett]

Seen a lot of strange stuff but never screw holding ribs to wing spars!

[Guest]

Hi
We have 4 wings for our BC12 restoration and are trying to make 2 good ones from the wings we have.

However - On 2 of the wings the ribs have been attached to the spar with what looks like woodscrews?

Was this ever an option or is it a result of a botched restoration attempt?

BR Ian

They do something similar on Aeroncas. There is an STC to use small #4 sheet metal screws instead of nails that back out .

Dave R

[MBednarek]

The STC for screws is SA02295SE (https://rgl.faa.gov/Regulatory_and_G...t=%20sa02295se), is held by Rainbow Flying Service of Moses Lake, Washington (https://rainbowflying.com), and also covers Taylorcrafts.

[PA1195]

Excellent find re the alternative means of rib attachment to wood spars! Good to have available. https://rainbowflying.com/shop?olsPa...ews-stc&page=1

Gary

[Guest]

The STC for screws is SA02295SE (https://rgl.faa.gov/Regulatory_and_G...t=%20sa02295se), is held by Rainbow Flying Service of Moses Lake, Washington (https://rainbowflying.com), and also covers Taylorcrafts.

I had not realized that Ron's STC covered T-Crafts also thanks!

J2 thru J4 too!

Dave R

[astjp2]

Excellent find re the alternative means of rib attachment to wood spars! Good to have available. https://rainbowflying.com/shop?olsPa...ews-stc&page=1

Gary

Not really Gary, the damage the shit out of the spars.

[PA1195]

Not really Gary, the damage the shit out of the spars.

Substantiate.

Gary

[Jim Herpst]

I would think the little screws would not harm the spar. Nails do not always stay put . Interesting dialog

[Ragwing nut]

I have never found a big issue with nails backing out of ribs on a t-craft, and I have taken dozens of wings apart. I found more with the head rusted off that backed out.

[astjp2]

Scews break the fibers, a Brad will split them

[PA1195]

Dr. Tim I can see what you're saying about the potential shearing of wood fibers with screws. Bellanca used small ring nails at one time but even they were prone to backing out and an AD followed. I think they reused the nails with maybe some wood glue. A call to Rainbow Flying Service the screw STC holder might be worth the time to get their basis for the STC. Surely any potential for strength reduction or damage has been addressed through testing.

Gary

[astjp2]

I have a hard time drilling bolt holes! Just because of the possible damage to the grain

[astjp2]

Oh and the Bellanca had smooth nails that came out, the put the ring shanks to stop it from backing out

[PA1195]

Thanks Tim for the correction on the Bellanca nail history. I had it done on my 7GCBC in a few spots. Tapped some back in or replaced with ring nails. Dry climate and spar flex were the cause I was told. Grabbing and shaking the wingtips up and down will make a doubter out of new pilots.

Gary