NH Duplex frame break

[neilchalmers]

Hello all,
I have a 1958 NH frame and have noticed that there is a gap forming below the top front engine mounting when I apply a little force. The gap is uniform and there seems to be a sleeve inside the tube. The opposite tube had a uniform line at the same spot although has not parted. I assume that the frame is joined at this point?
Any info would be appreciated.
Cheers

[neilchalmers]

[will_curry]

I've seen several break like that, usually under the strain of hauling a badly-aligned
sidecar. I'm still using one brazed up about 40 years ago. It's worth checking that
the bolts are a good fit in the engine plates and the frame lugs.

[Simon.Gardiner]

Many years ago a friend of mine had an FH that went on both sides in just that place. That too got fixed by re-brazing.

SG

[nevhunter]

Once it's been brazed you can't weld it in the normal way, unless you cleaned away all trace of the braze material. Since it's still aligned by the inner sleeve just vee it out and do it with nickel bronze. Best if you strip the frame out and weld it in the best position. (flat and rotate it as you weld). Nickel bronze is stronger than the steel used there. There will be minimum cleaning up if you do it carefully. Nickel bronze will just file with a sharp file. Nev

[neilchalmers]

All brazed up and looking good.
Thanks chaps.