Thursday, September 1, 2011


I wrote about making the two ends of the crib which consisted of the posts, a top rail, a bottom rail and the panel that is enclosed in the frame. I realize now that making the ends of the crib was the easiest part of the project.

The second part of the project is to create the sides of the crib. Both sides are open. I designed them according to CSA requirements. The vertical pieces are 1 1/2 inches wide and 3/4 of an thick. They are spaced 2 inches apart. Actually, CSA allow the verticals to be about 2 1/3 inches apart. It was easier to space them 2 inches apart.

The issue was how to secure the verticals to the top and bottom rail so that it was strong and would take lots of abuse from an active, growing baby. All things considered, I decided that mortise and tenon joinery would be the strongest joint for this construction. I had no idea what I was getting myself into. Design the joint was easy. I used the 'thirds' rule with common sense. The tenons were 1/4 of an inch thick and 1/2 an inch wide. The mortises were obviously the opposite dimensions in the rails to accept the tenons.

On paper, it looks completely doable in a short period of time. In reality, it took a lot longer than I thought it would. I have completed the process of cutting the tenons and the mortises. When I look back it was quite a task cutting 56 tenons and 56 mortises. Even though I already have a tenoning jig that I had built myself several years ago it took me and entire weekend to cut 56 tenons.

The tenoning jig works great. It holds the piece straight and tight. The problem was that the maple was so hard that I had to take small cuts or else it would burn the wood which it did anyway.

In the end, I had 56 precision cut tenons.

Now the mortises were an entirely different story. If I had a mortising fixture it would be a relatively easy job. But I do not have a mortising fixture, they are expensive and I do not cut mortises every day so I cannot justify the cost. Second choice would be to use my router on a router table. This would be a great idea but I do not have a router table. It is on my list of things that I am going to build for my work shop...right after I finish making this crib! The only logical choice was to come up with a temporary set up that I could use to cut the mortises and then take it down when I was finished which is exactly what I did. the setup worked well enough. It required a steady hand and a lot of good hand-eye co-ordination but I got all of the mortises done as well.

This is the set up. I screwed a piece of aluminum to a pine block that I had planed so that it was perfectly flat. I spaced the aluminum piece so that it lined up the router bit with the center of the rail.

Here are the first few mortises that I cut. they measured exactly in the middle of the rail. Not a bad setup.
Here you can see where I marked out the center and the edges of the mortises. I marked out the edges and put a mark on the rail where I had to place to router then I plunged three holes and cleaned out the mortise after wards. You can see that it makes a nice clean looking mortise.

Once I got the hang of it the work went fairly smoothly, it just took a long time to cut all 56 mortises.

Now I am ready to start fitting and gluing the verticals to the top and bottom rails.

1 comment:

  1. I don't understand the technical stuff but I can tell it was A LOT of work. Chloe is one lucky little girl!