I'm interested in the steps that your shop uses to process 4/4 stock into door and cabinet parts.
Being that I run a small shop, yield is important. Usually 4/4 is planed down just enough to see the color and figure of the species. Rails and stiles are ripped to 1/8 over width (more on long pieces) and cut to over length (amount depends on defects and cracks in end pieces.) Better boards are crosscut to panel sizes. At this point, everything is put aside for at least a day for pieces to warp, relax, crack, twist, etc.
I will continue to use this process in steps, depending on the parts. For instance, door panels will be face jointed and planed down another 1/8 or so and allowed to sit again. Rails and stiles will also go through this process 3 times; rough, relax, and final dimensioning. I try not to do the final dimensioning until I am able to machine and glue it up that day. After final dimensioning, I run everything through a drum sander to remove snipe and planer marks. Then it's off to the shaper or glue table.
This seems a bit overboard. I seldom have cracked panels or warped doors, and although it seems like a laborious process, I swear I make it up in later phases of construction when I have good, straight and uniform stock. I don't have a wide belt to run everything through, so the time saved sanding seems worth it alone. Face frame and door joints require only fine orbital sanding.
Any comments or suggestions? I'd love to hear the process small and even larger shops use, as some of us smaller shops envision being at that level some day.
What about just buying S4S material? It would seem a lot cheaper to me than going through all you go through. Do you get paid for all this "laborious process"? I would buy S4S for the stiles and rails, and edge-glued panels for the panels.
More importantly, there's no waiting for whatever's going to happen, just cut the stuff and put it together. We've done it that way for years and never had any problems in the "later phases" of construction.
Here's our solid wood production schedule for kitchen cabinet doors:
1. Rough rip - rough cross cut stiles and rails to final dimension plus allowances for further machining
We made thousands of doors using these methods with a near-zero reject rate (and our standards were quite high). If you're involved in higher production, then you can save even more effort by using production equipment in place of the planer-jointer-shaper combination.
If you are buying well made lumber, you can rely on its stability.
I do not have a waiting time between processes, except for glue to dry. This is a time-consuming process. If I were in mass production I would have to do it differently. Out of the hundreds of doors I have made this way I have not had to replace any. When I started woodworking in high school and then at my first job, we used only S4S lumber. What I learned then is why I do it this way today.
Comment from contributor A:
I have a process which is slighty different from the the rest I've read. First I would start by planing the rails/stiles 1/6 oversize, then the panels 1/6 oversize after they're glued together. Second, rip the rails and stiles (gang rip would save a lot of time). Third, shape all the rails/stiles. Fourth, crosscut rails/stiles to the desired measurment by setting up a stop block jig. This will enable you to cut 8 or more peices, making them all the exact same size. Fifth, crosscut panels. Sixth, cope cut the rails on the shaper, then the panels. Now assemble. There is one part I left out - after ripping rails/stiles, pass as many as possible trough the planer on edge, keeping a square edge. This ensures uniform width.