Applied Versus Captured Drawer Bottoms
Cabinetmakers discuss the strength, appearance, speed of construction, and perceived value of different drawer-bottom attachment methods. May 12, 2008
Given the strength of modern glues, it would seem to be at least as strong to glue the drawer bottom onto the sides rather than capturing it in grooves. Rabbiting the sides to leave an 1/8" tongue would seem to resolve the aesthetic problem. Does it create other problems? Other than aesthetics, is there a down side to an applied bottom? Are there advantages? Once you have the process down, is there any significant difference in the time or care that applied bottoms would take? Any suggestions are welcomed.
From contributor O:
Looks like you are trying to do almost as much work to get a product that might/might not be as strong. I can't answer if it would be as strong. It might be, might not. But you have to worry more about the 'perception' of strength than the actual strength anyway. I think many would balk at seeing an applied drawer bottom. Just my opinion.
From contributor A:
Depends on what slide you are using. We use the Grass Zargen or Nova drawers now, but used to build our own melamine drawer boxes. We used an applied bottom because we were using the Blum 230M drawer slides that screwed through the drawer bottom into the sides, so the edge of the 1/4" bottom was covered and the screws provided more than enough strength.
From contributor B:
I always do an applied drawer bottom when using epoxy coated slides because they support under the bottom anyway. Makes drawer building really quick, and my "selling point" is my drawers have more useable depth than the guy that captures the bottom in a plowed dado. If you set the bottom up even 1/4", you lose that 1/4" under the dado. I can build them in a hurry, and I can give them extra depth. It is a win/win situation in my book.
From contributor M:
Using any type of "side-guide" drawer slide hardware allows you to hide the edge of a bottom-applied drawer bottom. If you are going to use a bottom-mount hardware, like the current-craze self closing variety, it requires you to set your bottoms up from the bottom of the drawer in dadoes.
I abandoned drawer dadoes years ago with noting but beneficial results. But I still use side-guide hardware. So pick your poison according to what hardware you pick.
From contributor L:
If you are using Euro guides then applied bottoms are the only way to go. If you are using any sort of man-made drawer sides applied bottoms would be at least as good as, and probably better than plowed in.
From contributor C:
In my humble opinion, it is nice to be able to produce a dovetail drawer when asked, otherwise I think you can usually get the same money with any well made drawer box, unless they ask and then it is a good bit extra, otherwise just asking for extra work (cost) for limited benefit.
From the original questioner:
My thinking was that a 1/2" side times the perimeter of the drawer box gave a fair amount of glue surface. But, because it's not as commonly done, I wondered if I'd missed an issue.
Contributor M - thanks for the suggestion of dropping the slide to cover the bottom's edge. That's the kind of obvious solution that usually evades me for awhile.
From contributor V:
I think the dadoed in drawer bottom is a historic carryover. Before plywood, drawer bottoms were solid wood and usually worked into tongues at the edges. These were set into grooves in the sides to allow for cross grain expansion/contraction, typical frame and panel technique.
The process just got carried over to drawers after plywood and other manufactured sheet goods came along.
Even so, the dadoed look is neater. And of course, the "L" shaped side mount guide covers the side edges of an applied bottom. Its definitely strong enough simply glued and stapled.
From contributor C:
If you groove your sides and use the slides which wrap around the bottom , and are drilled to accept both side and bottom screws, both of these screw locations are in a weak place. They are either too close to the groove in the side, or too close to the fracture plane in the bottom, especially if your sides are plywood. A bottom screw into a plywood bottom is strong.
From contributor S:
We cut our parts on the router, use 5mm dowels, and captured 1/4" bottoms. This does take a bit longer, but I find a few advantages. The captured bottoms keep the box square, even if I have an unskilled laborer building the box. I don't have to worry about the new guy shooting a staple through the side, or getting it racked. The dowels line the sides up nicely, and again no need for fasteners.
Have you thought about using 3/4 material for your boxes and using your 8mm dowels? That Koch ought to be able to crank them out.
A question that I do have for the applied guys - what do you do about the front and back edges. I understand that the euro guides add some mechanical strength, but what about the fronts and backs? If you have a drawer that is 20" wide, the middle may need extra support.
From the original questioner:
Yes we run drawers on the Koch with 8x35mm dowels. The machine processes the parts faster than the operator can keep it loaded, (four operating positions, two bore and insert, two face drill.)
From contributor W:
Much of it depends on your buyer. However in my professional opinion if you're not making at least 1/2 - 5/8 thick solid maple dovetailed drawer boxes with at a minimum 1/4" ply bottom that's dadoed in and hot glued square and snug, than you're making a lower end draw box. It's not a craftsman tradition for any old reason, it's because it is the strongest way to build the drawer box. People who nail and staple things together to save time aren't concerned with quality; you have to decide what you're selling, quality or quantity. For me, I like charging my prices knowing my stuff will outlive my customers.