4 replies to this topic

[mk=john]

Hi

I want to restore the external door hingers for my 1960 mini. They are the very early brass hinges, and the pins and holes are quite badly worn.
Anyway, I have the hinge pin kit from Minispares (link below).

I would need to drill holes big enough to press fit the bushes into place, but what is the method of making sure they are perfectly alighed through both parts of the hinge.

Also, would I have to use a reamer to ensure a good press fit?

Click here

Thanks
John

[dklawson]

Brass hinges are indeed rare. I have a partial set somewhere.

You will want to ream the large hole for the bushing. What I call a drill press I believe you call a pedestal drill. That's what you are going to need/want. The best method would be to temporarily fit the old pin to the parts and attach the hinge to a wooden fixture. Remove the pin and orient your fixture on the pedestal drill so that a drill of the right size will pass straight down through the holes in both hinge parts. Then remove the short hinge part and drill (then ream) through the long part of the hinge to get the right size hole in the right alignment. (I'm picturing blocks of wood C-clamped together to allow you to adjust all the angles.)

You will then press the bushing into the long hinge part. (I would use some Loctite-680 [green] on the bushing prior to pressing it in). You are likely to find that the bushing closes up a bit when this is done and you will then need to ream the bushing just enough to get the pin to pass through. After that it will be pretty standard stuff... fitting the new pin, dressing the pin to match the hinge profile, and painting.

[mk=john]

Brass hinges are indeed rare. I have a partial set somewhere.

You will want to ream the large hole for the bushing. What I call a drill press I believe you call a pedestal drill. That's what you are going to need/want. The best method would be to temporarily fit the old pin to the parts and attach the hinge to a wooden fixture. Remove the pin and orient your fixture on the pedestal drill so that a drill of the right size will pass straight down through the holes in both hinge parts. Then remove the short hinge part and drill (then ream) through the long part of the hinge to get the right size hole in the right alignment. (I'm picturing blocks of wood C-clamped together to allow you to adjust all the angles.)

You will then press the bushing into the long hinge part. (I would use some Loctite-680 [green] on the bushing prior to pressing it in). You are likely to find that the bushing closes up a bit when this is done and you will then need to ream the bushing just enough to get the pin to pass through. After that it will be pretty standard stuff... fitting the new pin, dressing the pin to match the hinge profile, and painting.

Thanks Doug
I need to go and obtain a reamer set really, and suitable drills. i have a pedestal drill, and now need to make some kind of support to hold the hinge assembly firmly in place while I am drilling the holes.

[dklawson]

I almost forgot to mention this John.

Brass doesn't really like the angles on "regular" drill bits. As such, you can expect the hinge to want to "grab onto" the drill bit and/or get yanked upwards as you drill. To avoid this as much as possible, use progressively larger drill bits, slow speed on the pedestal drill, and a thick oil to lube the drill bit. Stop short of the bushing diameter and ream that last little bit out for the desired finished hole size. You'll benefit from clamping your fixture to the pedestal drill so it can't move much.

[mk3 Cooper S]

I used reamers on mine and made the pins to suit with the appropriate fit depending on which bit needed clearance and which bit need a transition fit.

I also drilled a hole down the centre of the pin (not all the way through ) and a smaller hole at right angles to it to act as a gravity filled oiler. I filled the hole woth oil and it lubricates the hinge and hopefully won't wear the soft brass again.