Welding to sills

[alfadave]

The sills on my Sud were repaired a few years ago.

But I now see that the bottom flanges are looking raggy in places

Is it ok to cut these off, and then repair with a flat plate under?

[LooLooSud33Spider]

Dave.
Be careful the sill sections add critical structural integrity of the shell. The reason they use a vertical seam to join the outer sill to the floor section as mainly due to the need to spot weld that seam during manufacturing process. Whilst the majority of the strength is in the sill section that little vertical seam will be adding to the overall strength of the sills.
What you’d be better doing is recreate the original seam by folding a length of 1 mm through 90deg. And then welding that to the floor and then you’ve got nice new steel to attach your sill seam to. Hope that makes sense
Lou

[alfadave]

Thanks Lou,
I''ll give it a good clean up and have a look. But most of the floor and outer sill looks good. Just the vertical seam is flakey.

I understand what you say about the spot weld . But I'm not trying to re create the original here. Just get my runabout up to MoT standard!

[Kegsti66]

Dave, that flange actually sandwich's three pieces together.
There is an inner strengthening panel that runs inside the sill. Outer sill on one side and the floor flange on the other.
Meeting at 90 degrees with the inner in the middle.

[alfadave]

Thanks Keith,
I remember seeing the innards when the welder repaired the sills for me.
Just the bottom flange seems flaky now, but I need to get under and clean it all up.

I wonder why they made the inner with holes rather than a solid piece? Might last longer if solid!

[LooLooSud33Spider]

The holes were added in an attempt remove some weight from the inner sill panel. Without weakening it look inside an old adroplane and you’ll see loads of structural members full of “Dimple Died” holes. The dimpled edge to the holes again adds strength

[alfadave]

The saving in weight must have been minimal compared to the overall weight of the car!

[Kegsti66]

As Lou says, the holes with a flange around it actually adds strength to its length.

[alfadave]

Adds strength until the bottom parts starts rusting away!
Call me old fashioned possums, but sometimes I think originality can be improved upon.

[alfadave]

Got out and under, and cleaned up one sill.
The bottom flange looked flaky, but after removing some weld and seam sealer looked better.
Pics to follow.

Welding was done by RBS welding in Manchester.

Those of nervous disposition, look away.

[LooLooSud33Spider]

Pics from Dave

[LooLooSud33Spider]

RH side