F4U spot welding

[greatgonzo]

I hope somebody familiar with Corsair construction can help me with this. It is known that Vought used with the F4U some non standard technology. Spot welding of the construction and skinning was one of them. I am trying to find out, which parts were spot welded. Also is the spot welding technique used on restored corsairs too? This could help to recognize the weld points in the good quality pics of existing birds, but I am not sure there is still anything to look for.

[JohnTerrell]

Just as one example, in all of the brightly-marked areas seen in these photos of a freshly rebuilt Corsair rear fuselage/empennage, those are all areas where there are lines of spot welds:
http://www.sandersaeronautics.com/resto ... 1-1024.jpg
http://www.sandersaeronautics.com/resto ... 5-1024.jpg
http://www.sandersaeronautics.com/resto ... 3-1024.jpg

The bright areas of the metal is where an acid wash has been brushed onto the aluminum to purify the surface prior to spot welding.

More on just the rear fuselage/empennage assembly can be seen here:
http://www.odegaardwings.com/corsair-pictures/


As you can see on the reverse sides of these sections, the skins are spot-welded to the stringers and ribs, with rivets applied in strategic locations and at the edges of the panel (to the longerons and joints/joining ribs).
http://www.sandersaeronautics.com/resto ... 2-1024.jpg
http://www.sandersaeronautics.com/resto ... 9-1024.jpg

On these sections of the wings, you can see more indications of lines of spot welding where there is brushed-lines/swaths on the metal that is a different tone. All of the rivets are dark in color/tone.
http://www.sandersaeronautics.com/resto ... 7-1024.jpg
http://www.sandersaeronautics.com/resto ... 5-1024.jpg
http://www.sandersaeronautics.com/resto ... 8-1024.jpg

Through the main cockpit section, again you can see how, for the most part, the skins are spot welded to the ribs, with riveting only mainly at the edges of the panels.
http://www.sandersaeronautics.com/resto ... 4-1024.jpg
http://www.sandersaeronautics.com/resto ... 5-1024.jpg
http://www.sandersaeronautics.com/resto ... 6-1024.jpg
http://www.sandersaeronautics.com/resto ... 8-1024.jpg

[greatgonzo]

Now, can you get a swell answer when you need one?

Thank You very much! You've been most helpful.

[AndyG]

Hi John,

that answered a long time mystery for me also, thanks very much too.

A question, how do the these aviation spot welds fair over time compared to conventional rivet construction, both from a structural and corrosion perspective?

(I thought previously that only the spars were spot welded, that gives a much greater insight into the overall construction)

many thanks

Andy

[Jerry O'Neill]

Here's a photo from the Igor I. Sikorsky Historical Archives showing to Vought Employees spot welding a Corsair part.
https://www.facebook.com/photo.php?fbid=10212335118045717&set=a.1281240203752.39608.1612480691&type=3&theater

[Pogo]

Fascinating thread, cheers to all!