Fuselage Tubing Diameters

[John M]

Hello,

I would like to get information on the fuse structural tubing diameters and possibly the wall thicknesses on a typical BC12D. The diagram on the website has numbers such as A-1234, but I don't know the diameters. It appears that there may be 3 or 4 different sizes? This is for a general model, so exact aircraft type may not be critical.Also, did the diameters change much over the years?

Thanks in advance for any assistance.

John

[astjp2]

Re: Fuselage Tubing Diameters

Prewar and post war airplanes also switched from 1020 mild steel to 4130 in some of the tubes, stiffness is the same but strength was improved Tim

[Hank Jarrett]

Re: Fuselage Tubing Diameters

If you have particular tubes we may have the ID and OD in our repair records. Start with the part number if you need or post a photo where you are pointing to the tube. Push comes to shove, there a number of wrecked fuselages around and someone may be able to actually measure it.

Hank

[John M]

Re: Fuselage Tubing Diameters

Hank, thank you. For example B-1504, B-1510, B-1807, B1809.

I was hoping to get the general ODs of all of them, but maybe there is quite a variety? For example where are all of the longerons typically one size, the bottom rear diagonals another size, etc.?

Any wrecked or otherwise accessible fuselages that you know of near Seattle, WA?

[Scott]

Re: Fuselage Tubing Diameters

longerons on my BC12D are 3/4"OD x.035" wall
most of the tubes aft of the rear carry-through are 3/4. I suspect they're all the same wall thickness as well but I only opened the lower longeron.
there are larger OD's in the gear structure and carry-throughs and smaller diameters, 1/2" I think as diagonals and cross-braces. I can measure the ODs if its of use to you but can't give you wall thickness info.
Scott

[Hank Jarrett]

Re: Fuselage Tubing Diameters

My 45 is uncovered and all teh tubes are accessible. I will get my fuselage drawings and check some part number dimensions. Hopefully we will get some verifications from others. I also have a couple of fuselage sections in thh hangar and can check some wall thicknesses.

Hank

[Scott]

Re: Fuselage Tubing Diameters

Upper longerons are 7/8" OD back to the fwd stab attach 3/4 aft of that. lower are 3/4
Some of the cross tubes are 1/2" some are 5/8
Diagonals are all four of these OD's depending on location

[John M]

Re: Fuselage Tubing Diameters

Thanks so much!

John

[John M]

Re: Fuselage Tubing Diameters

Thanks so much!

John