12-23-2016, 03:29 PM
The photos below point out a problem I’ve run into with the boxes I’ve been making. The pictures show two boxes. One is made of kiln-dried cherry and measures 11 ½ x 7 ½ x 3. The other is made of kiln-dried maple and measures 12 ¼ x 8 x 3 1/8. Both have badly twisted lids. All the wood used was free of defects such as twisting, warping, or cupping.
<img src="http://i1074.photobucket.com/albums/w420/jihhwood/cherry%20barrel%20hinge%20box%202_zps1qawhedk.jpg" border="0" alt=" photo cherry barrel hinge box 2_zps1qawhedk.jpg"/>
<img src="http://i1074.photobucket.com/albums/w420/jihhwood/maple%20barrel%20hinge%20box%202_zpsbxqpjzrt.jpg" border="0" alt=" photo maple barrel hinge box 2_zpsbxqpjzrt.jpg"/>
In both cases, the lids are “frame-and-panel” construction. The panel consists of a 1/8” plywood substrate, veneered on both sides. The veneer on the underside is a single piece in both boxes. In the case of the cherry box the veneer on the upper side of the panel consists of a single piece. In the case of the maple box, the veneer on the upper side of the panel is made up of shop-made veneer – thin pieces I arranged for aesthetic purposes to look decorative and colorful.
Before the glue-up, the lid panel was put into position (I cut a rabbet to house it). I spot glued the panel at the mid-point on the “short” sides of the rectangle. I left room in the rabbet for the panel to move feely.
The box was glued up; afterward, box and lid were separated at the table saw. I used 8 mm Soss hinges to attach the lid to the carcase. The lid closed perfectly.
Finish was three coats of paraffin wax. (To avoid darkening the hue of the wood, I did not seal it with super-blonde shellac – something I usually do when I make furniture and frames.)
The completed boxes were put on a desk (out of direct sunlight) in a spare bedroom. We have oil hot-air heat, and do not keep our home very hot (63 daytime, 55 at night). Nevertheless it has been cold where I live (a couple hours north of NYC) and humidity in the house does vary quite a lot (it was a low 29% this morning, for example). When I inspected the boxes a couple of hours ago (the box had sat on the desk for a few weeks), I discovered that both of the lids no longer sit flush to the top front edge of the carcase. They appear to have twisted, as the photos show.
I am stumped as to why the lids have twisted. I asked myself these questions:
(1) Did I allow enough room for the panel to move if it wanted to? I think I did. (2) Did I glue the panel into the rabbet too generously or in the wrong location? I think not.
Thanks in advance for any guidance you can provide – either why this happened or how to “failure-proof” boxes that I am yet to make!
<img src="http://i1074.photobucket.com/albums/w420/jihhwood/cherry%20barrel%20hinge%20box%202_zps1qawhedk.jpg" border="0" alt=" photo cherry barrel hinge box 2_zps1qawhedk.jpg"/>
<img src="http://i1074.photobucket.com/albums/w420/jihhwood/maple%20barrel%20hinge%20box%202_zpsbxqpjzrt.jpg" border="0" alt=" photo maple barrel hinge box 2_zpsbxqpjzrt.jpg"/>
In both cases, the lids are “frame-and-panel” construction. The panel consists of a 1/8” plywood substrate, veneered on both sides. The veneer on the underside is a single piece in both boxes. In the case of the cherry box the veneer on the upper side of the panel consists of a single piece. In the case of the maple box, the veneer on the upper side of the panel is made up of shop-made veneer – thin pieces I arranged for aesthetic purposes to look decorative and colorful.
Before the glue-up, the lid panel was put into position (I cut a rabbet to house it). I spot glued the panel at the mid-point on the “short” sides of the rectangle. I left room in the rabbet for the panel to move feely.
The box was glued up; afterward, box and lid were separated at the table saw. I used 8 mm Soss hinges to attach the lid to the carcase. The lid closed perfectly.
Finish was three coats of paraffin wax. (To avoid darkening the hue of the wood, I did not seal it with super-blonde shellac – something I usually do when I make furniture and frames.)
The completed boxes were put on a desk (out of direct sunlight) in a spare bedroom. We have oil hot-air heat, and do not keep our home very hot (63 daytime, 55 at night). Nevertheless it has been cold where I live (a couple hours north of NYC) and humidity in the house does vary quite a lot (it was a low 29% this morning, for example). When I inspected the boxes a couple of hours ago (the box had sat on the desk for a few weeks), I discovered that both of the lids no longer sit flush to the top front edge of the carcase. They appear to have twisted, as the photos show.
I am stumped as to why the lids have twisted. I asked myself these questions:
(1) Did I allow enough room for the panel to move if it wanted to? I think I did. (2) Did I glue the panel into the rabbet too generously or in the wrong location? I think not.
Thanks in advance for any guidance you can provide – either why this happened or how to “failure-proof” boxes that I am yet to make!
