12 replies to this topic

[MiniBGT]

Does anyone have experience or ideas on how to repair the thread at the tip of a top Mk1/2 external door hinge?  Mine has obviously been overtightened at some stage and when I try to securely tighten the nut behind the A panel it pulls the stud out.  There is very little metal at the pointed end of this hinge.

[Daz1968]

They are cast so only way I would think would be a helicoil thread repair, but as you say not much room,

[MiniBGT]

That is the problem Daz1968, this one is wafer thin at that point.  It the underside of the hinge was not sculptured it could be drilled and tapped 1" back and the A-panel re-drilled. It maybe that I must purchase a new one and spray it.

[Daz1968]

As a temp repair put on some epoxy resin and set stud in position. Then keep eyes open for a replacement hinge, note all 4 are different. If you can get an original one as the new ones are aluminium

[MiniBGT]

Perhaps I should go to Beaulieu at the weekend.

[1984mini25]

If you can weld and the hinge will need repainting afterwards. Drill and tap the damaged thread all the way through the hinge and out the other side. Grind away some of the front and thread a new bolt (with the head removed) or stud through form the from and weld it in place. Welding the bolt/stud to the hinge and filling in the front face, so that it can be ground down and reshaped.

[MiniBGT]

I like the idea 1984mini25 but, Daz1968 implied that as they are cast they cannot be welded.  Have you actually used this method successfully?

[Daz1968]

I have seen mig repairs on cast but not really good where strength is needed, maybe ok for this application. At then end of the day you have nothing to lose by trying

[elf66]

Welding cast iron can be done using a mig if you pre heat the casting until its cherry red then weld it before it cools. If you dont pre heat it, the weld will just crack where it joins the casting. Once welded just let it cool slowly.

I have successfully used this method on a cast iron bell housing and a dif casing so a mini hinge should be no problem. The only down side is you need a lot of gas to get it hot enough! 

[1984mini25]

I like the idea 1984mini25 but, Daz1968 implied that as they are cast they cannot be welded.  Have you actually used this method successfully?

 

I've done the same repair to a few of the mik1 hinges I used on my 89 project, to witch I converted to use proper mk1 hinges. My hinges were cast, but were definitely not cast iron.

 

Anther option could be to braze/silver solder new studs in, but that's not something I've personally tried. Although it did work on a very early set of brass mk1 hinges I bought/was going to use.

[tiger99]

It seems that MIG brazing would be ideal, but the price of a reel of wire will shock you! I don't know why it is so expensive, even if it is technically bronze. Good on cast iron. TIG or gas brazing, or bronze welding, would require maybe 1 rod, so would work out a lot cheaper.

 

But are they cast iron, which does not weld easily, as discussed correctly above, or are they cast steel, which in most cases does weld? Several ways of finding out, one obvious...

[Dr s]

Mine had a second hole drilled and a machine screw fitted from the outside.

[MiniBGT]

That's the solution that I have been contemplating for the past few days.  Do you have any photos of what it looks like please?