Its a toughie...
One option is to use double stick tape to locate the lid hinge. So, install the case leaf, assemble the hinge with the pin...or with a slightly loose drill bit, so you can get it apart very easily. Use the double stick tape on the lid side leaf. It can be tough to get a good adhesion on the tape, but a couple of tries gets it...gently lower the lid onto the assembled hinge. Don't drill your pilot holes until you are comfortable that your adhesion on the lid side leaf was positive. This is a two person operation, I think, do it several times until you get the sense you are where you want to be.
The other thing to watch, after getting the hinge where you want it, is drilling the pilot holes. The bit finds it hard to center on the countersunk hinge leaf hole, and moves the carefully placed hinge leaf. Use a bit that is the exact diameter of the countersunk hole. Given the countersunk and the bridge point, the bit will wander still, but with a light touch as you start the hole, let it enter the wood far enough to get past the countersink and the bit point, and if you do it lightly it will center nicely. Then change bits to the proper size pilot...gently let the bit find the center of the previously started hole and finish your pilot.
This is really a pretty tricky thing to get right..even if you're a shop troll.
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
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Original Message:
Sent: 11-02-2017 21:36
From: Craig Miller
Subject: Need advice on installing lid hinges.
I have a customer with a Mason & Hamlin BB that needs both original lid hinges replaced. The originals were damaged because someone removed one pin and then someone else lifted the lid. Luckily only the hinges were damaged. Replacement hinges are available, but the screw holes do not match. I will need to fill the holes in both the lid and the case and then re-drill new screw holes. I'm not sure how to do this and have everything line up. I can attach the hinges to the case, and then mark the screws for the front hinge by reaching under when the lid is sitting flat in the case, but I'm not sure how to mark the holes for the rear hinge. Any suggestions?
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Craig Miller
Marietta GA
770-321-9390
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