Shoulld a piano hinge be mortised for a trunk lid ?

[Herb Linderman]

Getting ready to install the lid on a trunk and l was wondering if I should mortise the piano hinge. I don't really care for the gap that results if you don't mortise. Not sure how deep to mortise for the hinge or if I should do one side only. The hinge is not flat when folded up so I would be guessing at how deep to mortise. I have searched for instructions but was unable to find any. The only tip I found was to countersink the screw holes in the wood so that the screw heads don't bottom out in the wood. This is due to the thin material of the hinge. Any suggestions or advice on the best way to install the hinge.

[Andrew Hughes]

Herb you can mortice the hinge but if your lid may not close in the front,if the back of the lid touches before the front.So if you close the hinge and measure the thickness.You can split the number in half,That's the max depth.For the lid and trunk.Its better to have a gap in the back,i also don't like a big gap and even a little one seems big.Hope this helps Aj

[Mike Cutler]

Herb

Piano style hinges can come in mortised and non mortised styles. It sounds as if you have a mortised hinge.

As Andrew stated to find your mortise depth, fold the hinge as if installed and measure the thickness at the barrel, or pin. Divide in half and that should your mortise depth.
The width of the mortise is a little subjective. I like to have the hinge pin just slightly hidden by the wooden material so that there isn't a gap when you look at it. Some folks make sure the entire pin is exposed.
Pre drill all of the mounting holes in the wood. I know about countersinking the pre-driled holes, but I always thought it was too stop the hinge from lifting up, because the wood was expanding at the screw insertion point. None the less, it's a good idea.

[Carroll Courtney]

If you should miss on the depth and its just a tad to deep then use some thin/thicker paper as a shim.I have use the thicker cardboard that is on the back side of a notebook,now only two of use knows about my mistake.----

[Mike Cutler]

If you should miss on the depth and its just a tad to deep then use some thin/thicker paper as a shim.I have use the thicker cardboard that is on the back side of a notebook,now only two of use knows about my mistake.----

Now that is a great tip!!!

Thank you Carroll.

[Matt Day]

If you should miss on the depth and its just a tad to deep then use some thin/thicker paper as a shim.I have use the thicker cardboard that is on the back side of a notebook,now only two of use knows about my mistake.----
You might have left off a couple zeros to that number Carroll ;-)

[Herb Linderman]

Well I guess the way to do it is to sneak up on the depth of the mortise and keep some shim stock handy. My hinge is a 1-1/2" solid brass one from Lee Valley. The hinge barrel measures .181 so I think I will start with about 1/16 depth and then check the fit. As Andrew said the gap is better at the back than the front. My material is 3/4 thick oak so I think I will set the hinge edge flush with the wood thickness. I was really surprised at the lack of directions for installation on the internet. Learned more about it here than anywhere else. Thanks for the help folks. Don't worry Carroll your secret is safe with me. :) Oh, and by the way happy new year.

[Bill Huber]

I have not done a lot of piano hinges but the last one I did this is the way I did it.

I measured the thickness of the hinge and then divided it in half, then took some off of that.
Set up the router with a straight bit and an edge guide.
I used 2 scraps of the same wood I made the box out of and made test cuts in both.
Clamped the two boards together like it was the back and the top.
I got the router set to the point it was a real tight fit to get the hinge into the slot, it was to the point I had to tap it in what a small hammer.

This worked out very well, when I installed the hinge and everything was done, with the lid closed I could slip a playing card in the back and couldn't in the front.

[Jim Becker]

You can, but it would be a "not fun task". I've never even considered mortising that type of hinge. All of the piano hinges I've used do not have provisions for flush mounting screws, either.

[glenn bradley]

I do as Bill does:

I measured the thickness of the hinge and then divided it in half, then took some off of that.

And as Jim points out I did use a HSS countersink and dress all the holes for flush screwheads. I did this with the hinge in position so that I coutersunk the material behind each hole as well. It is time consuming but, we're talking about 20 - 30 minutes for the whole job so, relative to the time I had in the piece it was not much for the look I wanted.

303129

[cecil rolfe]

I only mortice the chest side for the full depth of the hinge. It just mounts on the surface of the lid.

[Mike Schuch]

I have not done a lot of piano hinges but the last one I did this is the way I did it.

I measured the thickness of the hinge and then divided it in half, then took some off of that.
Set up the router with a straight bit and an edge guide.
I used 2 scraps of the same wood I made the box out of and made test cuts in both.
Clamped the two boards together like it was the back and the top.
I got the router set to the point it was a real tight fit to get the hinge into the slot, it was to the point I had to tap it in what a small hammer.

This worked out very well, when I installed the hinge and everything was done, with the lid closed I could slip a playing card in the back and couldn't in the front.


I would definitely test your depth by hinging together two scrap boards BEFORE you start in on your chest like Bill suggests!