Before I attack the stepped pattern, it made sense to work on the bridle joints that occur where the top of the posts meet the ends of the top rails. Using my super sled and a small attachment I made for cutting tenons, I made the mortise on the top of the posts using a standard blade by making a pass, rotating the board and taking another, before finally moving the fence and using a 3rd pass to clean up the center. The result is a perfectly centered mortise. The only problem I find I have with this technique, and frankly I don’t know what I can do to get around it, is that the wood tends to bend inward once the stock is removed. For some reason this seems more pronounced this time around compared to when I built our entertainment center. My tentative plan is to make a few wedges that I’ll jam in to spread the two halves apart when it comes time for the final glue up. It will be “interesting”.
While I could in theory cut my tenons at the ends of the rails with the same attachment, I find it much easier to creep up on a good fit by slowly raising the blade and making horizontal passes.
Since this produces a slightly rough result, after 99% of the material has been removed I remove the remaining irregularities by sliding the board across the blade, much like you would when cove cutting.
This past weekend by parents came up and my Dad and I spent the better part of two days working on the crib. On Saturday we worked exclusively on mortising. There sure are a lot of mortises in this project! Before he came I built an auxiliary fence for my mortiser. I was not happy with the results I was getting the past when I simply help the stock in place. I used some old inline skate wheels to hold the stock in place. These allow me to slide the stock left and right when it is not clamped in place. I find these doing a much better job holding the stock down when raising the mortising chisel compared to the attachment that came with the mortiser. For now I use a simple F-style clamp to hold the stock against the fence.
After making a series of square holes, we would come back for a second pass to connect them all up. I saw this technique recently and it really makes a difference. By plunging into solid wood in the first place the chisel is equally supported and does not want to move left or right. During the second pass there is no wood on both the left and right of the chisel, so while unsupported the chisel isn’t biased and does not move. Between the auxiliary fence, sharpening my chisels with a cone sharpener, clamping the stock in place and this new technique for making the initial set of holes, I’m finding I’m getting much better results.
Mortising took a long time in part because a number of the mortises were stepped since we were making them before cutting out the stepped pattern. That, and the fact that the various parts are of various thicknesses required a number of depth stop adjustments, but in the end we got it all done in one day.