Best way to do an invisible pin hinge in a small box

[jtpr]

I'm putting together a small box as a gift. I only have a couple of days to get it done so it won't be real fancy. Anyway, I wanted to do a top that hinged like this:

believe it is a pin that connects the two sides with the back of the lid. In this type of box does the front handle and the aforementioned pins support the top, or does the back have a rabbet? Is there a method to calculate where to place the receiving hole in the top for the pins or is it trial and (god forbid) error? As I said, I don't have a lot of time, so I kind of have to do this without a prototype build first.

Thanks, Jim

[Josh]

I don't think there could be a rabbet because it would prevent the very back of the lid from dropping down as the front comes up, wouldn't it?

Josh

[jtpr]

That is exactly my thought. I might have to burn some midnight oil and make a prototype, I was hoping somebody here had done this.

-Jim

[Teamcasa]

Why not make a spring pin hinge? Dave

[MikeMac]

I built the exact same box. (almost ;) ) The pins in the lid are 1/8" brass into the sides.. with a 1/4 round on the back edge.

[OneThou]

I recently finished a similar type box

masking tape to center and hold the lid in place, then the drillpress to drill for the brass pins, worked out perfect. The pins are exposed at the sides, but the polished brass is decorative. No rabbets, the lid is held by the pins at the rear, pins are glued to carcass sides, float in the lid section and are exact length so lid cannot shift side to side, lid is held at the front using the "tongue" as the depth stop. Spacing around the lid to carcass was pretty tight and had to put a slight chamfer on the upper rear portion of lid so it would clear the back when opening

Joe

[Josh]

What kind of pins do you think such things use? A pogo-pin or spring pin like in watch? Or is it a solid pin which has to be inserted from the inside somehow?

I did a recipe box for SWMBO and I hollowed out the inside of the lid with a router, so that if one held the lid upsidedown, it would look like a small dinner tray. Mine didn't use pin hinges, but if you did a lid like that, you could then drill small holes through the "wall" of the lid near the back where the pins (or brads or whatever) would go. Then you could assemble the box without it's bottom and set it upside down on a flat surface. You could then set the lid in place inside the upsidedown box. The flat surface would ensure that it was flush with the rim of the box. Then you could insert brads into the pin holes in the inside of the lid and press them into the sides of the box to mark the hole locations. In fact, if you sized the lid at first so that it fit quite snugly inside the box your holes would be very accurate. You could trim the lid afterwards to leave a little room for expansion.

Unless the box could then be disassembled again, you might have a hard time actually drilling the holes in the sides, once they are marked unless you have a really small drill. If you have a flexible drill extension (I have one with my Dremel tool), that would probably work well.

Josh

[Oleg Lego]

The jtpr entity posted thusly:

Placement of the pins will depend on the geometry of the lid at the rear of the box. If you round over the top rear, place the pin at the center of the roundover radius or a little toward the front of the lid.

I was thinking about the pin idea a few days ago, and thought a nifty (and puzzling) way to do it would be to drill the holes in the top deep enough to take the whole pin plus a bit, then drill the sides to take perhaps half the pin length, and to come very close to the outside of the box.

Make the hole just a tad larger in diameter than the pin diameter. Then use a syringe/needle to place a little superglue or epoxy in the bottom of the side hole. Finally, place the pins (steel) in the holes in the top, and use a rare earth magnet to draw the pins into the side holes, so they come into contact with the glue. If the side holes are deep enough, the magnets will apply plenty enough force for superglue.

A bit of bother, but think of the puzzled looks of those trying to see your hinges/holes.

[Josh]

Now that's a COOL idea.

[jtpr]

I thought the way it was done was to put the pins in the carcass before assembly, then do the glue up, and put it together around the top with the receiving holes. But your way sounds like more fun.

-Jim

[Oleg Lego]

The jtpr entity posted thusly:

Heh!

Figures.. a REAL easy way to do it. The idea of the pins came to me while I was reading an article on 'secret compartments' in furniture or boxes. One of the methods consisted of magnets attached to plungers that would unlock the compartment.

[Randy Thomas]

My approach would be to drill the holes in the lid deeper than they need to be and put springs in before the pins. Compress the pins into the lid, slide it into the box and wiggle it until the pins snap into place in the sides. Invisible, but if you had to you could work one of the pins back with two thin blades to get the lid off again.