16 Jun
Episode 21. The Krenov-inspired cabinet: Knife hinges
Posted in Blog, Cabinetmaking, Krenov by Al Navas (Sandal Woods)Download Quicktime (*.mov)
In this episode I show how I did the layout, and chopped the mortises for the knife hinges in the doors, and in the carcase. Then, for the first time, I do a dry fit of the frame and panel doors to the carcase.
The knife hinges provide an elegant solution in this cabinet, because they are unobtrusive; they remain hidden for the most part, with only the heel showing a fraction of the hinge. They are seen only when we open the doors.
The tricky part of using this type of hinge is the layout: The more accurate the layout, and the more accurately we cut the mortises for these hinges, the better they appear once we finish chopping the mortises. The secret (I can’t remember where I read it) is to cut inside the dimension of the hinge, and then enlarge the mortises to final dimension when we reach at least half the final mortise depth. This ensures a tight fit; on the other hand, if we start at full mortise width, we run the chance of ending with sloppy mortises, much wider than the hinges.
Chopping the mortises using hand tools, using only sharp chisels and a small hammer, is a pleasurable experience. This is the time to take our time, and do a good job, for the reward is nice-looking, and tight-fitting mortises around the hinges. I found myself taking breaks, both planned and unplanned, during the time I was chopping the hinges. Planned, to allow me to retain my concentration, and unplanned due to powerful storms that swept through our region. But over the course of two days I finished the eight mortises, with total time of about 6 hours on the 8 mortises.
Remaining patient is absolutely key, to make it a pleasure to do this job. Turn on some jazz, or whatever favorite music you enjoy, and get it done!
Now, an apology to Norman Pirollo, of Ottawa, Ontario, Canada: Norman, I made a typo on the web site address I gave for your blog. The correct URL for Norman’s The Refined Edge web site is: http://refinededge.blogspot.com/ . Norman does superb work in his studio; from reading his blog I have learned several hand tool techniques I employ in the building of this cabinet. And, after reformatting my 500GB hard disk drive (the result of one of the brutal storms that swept through here), and other video rendering problems possibly caused by power surges, I did not dare go back to make changes to the final version of the video.
Relevant links: All posts in my blog dealing with the Krenov-inspired cabinet, from veneering, book- and slip-matching, to making the doors.
Mark Mazzo
on June 17 2008
Hey Al,
The cabinet is looking very nice. Love those spalted maple panels!
Nice work on the hinge mortises as well. I was wondering whether you’ve ever tried an alternate method - rather than staying away from the marked knife line and then creeping up on it after reaching the correct depth. What I usually do is to chisel angled “V” cuts from inside the mortise toward the knife lines all around gradually working to final depth. Then I pare away the material from the center of the mortise. Both methods are fine and work well.
Keep up the great work.
–Mark
The Craftsman’s Path
Al (Sandal Woods)
on June 17 2008
Mark,
.
Thanks for dropping by, and for your comments and suggestion on the alternate method of chopping the mortises. I did try the “V” method for a limited time, but had better luck staying to the proper dimensions by using the method I describe. Of course, at the time I used chisels that were (very) dull. I finally learned how to sharpen them properly, though; it makes a huge difference!
.
I will try the “V” cuts, as sharper chisels should give me much better results. Thanks for the reminder, Mark!