Tail Spring Mount shims ??

Instructions says to "make 3/4 square from scrap aluminum to shim any gap between the WD-409 Tail Spring Mount and the F-811 Bulkhead Assembly"


In the middle, between both of them, the mount does not contact the bulkhead.


Wouldn't it be better if the shim was triangular shaped corresponding to the whole face of the mount?
This to better distribute the load from the mount to the bulkhead and to eliminate the off-set angle (top to bottom) between the bulkhead and the mount created by the shims?

Thanks !!

Hi Eric-

If it were me, I'd prefer to have as much surface contact between the weldment and the bulkhead, avoiding a gap created by a small shim on the bolt area only. I am by no means an engineer, but by having a more mating surface would help distribute the load more evenly across the bulkhead vs. just in shear on the bolts.

I had a small gap on mine, but it was across the entire surface. I made a shim that replicated the entire weldment surface. Hard to tell by the pics but looks like welding process may have created a slight curve on your weldment ends. You might try to gently bend the weldment ends back to flat and then see if the gap disappears or at least get the gap even between both weldment and buldhead. Then you can create a shim that's fills the entire gap vs. just where the bolts go.

My 2 cents....

In additon to needing a shim, I buggered up one of the flanges, so I made a shim to back up the entire spring mount that also incorporated a new flange.

Shim fabrication

Here's what I came up with;
It took a few layers of aluminum sheet, and I made sure I had a "handle" to grip it so I could maneuver it into position…the handle came in useful during drilling and bolting. This was my best attempt to create a "wedge-shaped" shim to fill the void.

[URL=http://s1381.photobucket.com/user/AAflyer/media/IMG_2296_zps776601b6.jpg.html]
[URL=http://s1381.photobucket.com/user/AAflyer/media/IMG_2298_zps348c566f.jpg.html]
[URL=http://s1381.photobucket.com/user/AAflyer/media/IMG_2287_zps82163f8d.jpg.html]



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http://i1381.photobucket.com/albums/ah213/AAflyer/IMG_2286_zpsc7489b55.jpg
http://i1381.photobucket.com/albums/ah213/AAflyer/IMG_2285_zps4ac1bd34.jpg
http://i1381.photobucket.com/albums/ah213/AAflyer/IMG_2287_zps82163f8d.jpg
http://i1381.photobucket.com/albums/ah213/AAflyer/IMG_2296_zps776601b6.jpg
http://i1381.photobucket.com/albums/ah213/AAflyer/IMG_2298_zps348c566f.jpg

Thanks!!

Thank you to all for your great replies!!

I will check the mount for straightness.

And I like the "handle" idea, I will do that on a full size shim.

I see your shims are on the 812 bulkhead.

Mine would be on the 811, anyone with comments regarding shims on either?? I don't think it really matters on which one it is...