"Art Box" Tutorial #8: It all hinges on this.

Before shaping the lid we need to put in our hinge pins and fit our handle.
Why now?,you may ask.
Two reasons:

The hinge pins keep the lid positioned during the carving stage.And its also to ensure that we know what areas to avoid with the grinder.We want to preserve as much wood over the pins as possible.The same holds true for the handle.Its best to cut the mortise in the lid for the handle while the lid is still flat.And we want to be careful around the area near the handle.

Pin location:
As the lid drops into the box it scibes a larger arc than it would if we were using barrel hinges or butt hinges.If we locted the pins at the far back corner,then the lid would contact the back lip before it fully opened.

After much experimenting, I came up with a placement that allows the lid to swing down into the box and then lean back enough that it will stay open on its own.Also,this location will position the pin 1/4’’ up from the bottom of the lid,which will be in its center after we grind away the top portion of the lid.
( Remember,we have a lid that is 3/4’’ thick,and our recess is 1/2’’ deep,which leaves 1/4’’ of the lid standing out of the box.So,if we shape the top of the lid down to the lip of the box,we will end up with a lid that is only 1/2’’ thick at its edges,which places the pin in the center of the edge.)
More on this later.

You can use a drill press or with a hand drill if you are carefull.I made up a simple jig using the hardened centers out of some old VIX bits.It is just a 90 degree corner with a bushing to drill one pivot hole and another on the other leg.I then move it around to the other corner and repeat.A good piece of dense hardwood would service just as well for many boxes.

The picture below shows the lid removed for illustration only.

Tip:
Secure the lid with tape while you drill your pin holes.Make sure the lid is bottomed out and all the way to the front.

Drill into the lid about 3/4’’ to ensure the pins are well seated.

I use roofing nails about 1 1/2’’ long as temp pins because they are easier to grab.They will be in and out many times as you trim the back of the lid so it will open.

Before we can open the lid we need to pare away some wood on the top and bottom,at the very back.
First,remove the lid and set it aside.Take a sharp chisel,or using a sanding block,remove the leading edge of the rabbet in the pocket.You will be making a chamfer about 1/4’’ wide.Dont worry about dressing it up at this point.Just take off the “corner” of the rabbet from pocket to pocket.As the lid sweeps downward its corner will hit this corner…so we remove a little of both.
(If your pin holes are a little low,or off side to side,then you may need to take more or less)

Next,set the lid back into place and while holding it firmly in place,mark a pencil line around back of the lid, at the point where it rises above box lip.Extend this around the corners,just past the pin holes.Now,bevel the top/back corner of the lid as shown,sanding down to that line.Do the back edge and just around the corner past the pin holes a little.

To clarify:
What we are doing is removing any wood at the back edge of the lid that sticks above the back lip of the box.As the lid pivots,the front comes up and the back drops down,but any wood above the pin actually moves backwards at the same time,hitting the inside face of the box which causes it to bind up,and thus,wont allow it to open.So why dont we just remove all of the wood above the pin holes ? You could do this,but you would need to grind away the back lip also,otherwise the lid would be below its level.And the top of the lid at the back would have a pretty steep taper,which I dont care for.

We need to leave the wood just below the taper you made,untouched for the time being.But we need to taper the bottom side of the lid,at the back and corners,so the lid will sweep downwards.This is difficult to explain,and takes alot of trial fitting to get it right.Its not hard,just sand a little,put the pins in and test it.Go slow and easy. Tip:
Wiggle the lid up and down when you have the pins in,even if its a little bit,remove the pins and look for rub marks where its tight and sand those away.Keep doing this.

Warning: I want to caution you about going too fast, because it is very easy to remove too much wood at the back, leaving a thin line that will disappear if you grind into it. Final fine sanding will remove additional wood,aggravating the problem even more.If you arent sure how much wood you have left along the back edge,then just stay away from there when shaping.

This photo
shows a side view of the lid after beveling the top/back edge and bottom/back edge and corners.Final fine sanding will be done later.
Here you can see the line where we stopped the top bevel,and if you look to the far right,in the middle,you can see a flat spot about 1/4’’ high.That is the only area that is still in contact with the back of the box.Carefully hand sand along this line until the lid opens without rubbing.Do this at a downward taper.
Keep in mind,that your finish will add little material to each surface and you may get areas where it will rub.This is one of those things that depends on many factores including humidity.Just be sure it works pretty good for now and you can fine fit it later,just before finishing.

And here we have a working lid.

Next we will be fitting the handle and cutting a seat for it in the lip.

-- " If I can make it,so can you" Andy in Oregon