1951 A10 lower front engine to frame stud...

[Swarfcut]

In my youth we just used a length of Whitworth threaded bar and enough washers to centralise the crankcase, then more washers and nuts to get a nice fit for the exhaust pipes.

  In these more enlightened times I would suggest boring the well fretted crankcase holes just an inch or so deep and turning up a top hat bush which is a nice snug fit into the case and onto the mounting through bar. The bar will be a nice fit into the bushes which join the front and rear frame members.  Then thread each end of the bar, but make sure not much of the thread enters the frame bushes.  This means that everything fits nicely and the chance for further fretting is reduced. Choice of material? Some more enlightened member will be along soon.  Studded bar worked, so mild steel should do unless you have access to the more exotic suggested metal.

  Swarfy

[RDfella]

I'd say mild steel was a bit soft for that. I'd prefer EN32 but when stuck for small amounts of material for such things as decent studs, etc , I usually get a long allen (capscrew) bolt, cut it to lenght & thread it. Quite high tensile and machines fairly easily.

[duTch]

 

.......In these more enlightened times I would suggest boring the well fretted crankcase holes just an inch or so deep and turning up a top hat bush which is a nice snug fit into the case and onto the mounting through bar. ...........

 That's a sound idea, but precision alignment is imperative, there's no room for error (in my humble opinion.....) No doubt the holes are elongated due to loose nuts, so to avoid the risk of misalignment of the 'tophats' and depending how 'elongated, would be almost better to use as-is (iknow,I know- a bit rough but....), and ensure the nuts stay tight....

 I agree that harder metal than soft cheese bar will be better, mine's 7/16" BSC