14 August 2013
At some point I made a "treasure box" for my older son that basically amounted to me practicing some box joints and giving him the results. It turned out to be a bigger hit than I thought it would be and my other son has been begging for a treasure box. I really didn't want to make another boring square box, so I set out to make a treasure chest with a rounded top.
I started out by mocking up the box in cardboard to get the dimensions correct. I showed that to my wife and we agreed that it was too big, so I cut it down to a more appropriate size. At this point one of my sons looked at the mockup and said "Is that it"? Thus started a long project during which the boys continually asked "Is it done yet"?
I decided to use high quality pine for the project. Based on that I decided early on not to stain the project. I debated between hand cut through dovetails and machined half blind dovetails and ultimately decided on machined. This was primarily a time saving decision since I was going to make four chests. I did not make detailed drawings or CAD on this project because I had a good idea of how it would come together and I had a cardboard mockup for dimensions. I had one open question when I started - how to round the underside of the slats used on the top. I did not find an answer to this online because most of the chests I found online had flat bottom slats laid onto a rounded edge. This creates little gaps that I was not satisfied with. I had some idea of how to solve this, so I started building.
At a glance, the treasure chest is:
The basic construction steps:
My contribution to treasure chest building is a method of rounding the slats for the top. I accomplished this at the router table. The first step is to create two curves that match the side curves of the chest using the same template. These curved pieces get secured to the router table spaced as in the picture below so that the slats can sit across both pieces and the edge (3/4" or so) can contact the router bit (I used a 1/4" bit). I used some double sided masking tape and made sure that the pieces were secured. Whatever you use you will need to make sure that these pieces are secured. The fence should be positioned so that the front of the bit is just greater than 5/8" from the fence (assuming your sides are 5/8").
Once that is all setup it's time to round the slats. The slat cannot be allowed to roll on the rounds. I ended up using some thin pieces of wood taped to each side of my slat to prevent it from rolling. As you cut you will need to hold the slats securely perpendicular to the fence. I found that I could use my hand to hold the piece perpendicular to the back rounded fixture, which effectively held it perpendicular to the fence. Then slide the piece into the fence repeatedly to remove most of the material. The piece will want to twist as you push it into the bit. You need to control the piece and you should be holding it near the rounded fixture that is further from the bit. Once most of the material is removed then run the piece over the bit from one side to the other a few times always keeping it perpendicular to the fence. If you have a slot in your router table and a miter gauge then you could probably use that to keep it perpendicular for this step. After these operations you should have a slat that fits onto your box nicely with no gap!
All I need now is some treasure!