Screws for securing back of plywood bookshelf

[Yasha Renner]

Then I run horizontal nailers across at the VERY top and near the bottom.

Hi Mark. I'm with you until this... not quite sure what you're describing here. You mean you attach a 1/2" thick piece of particleboard or MDF to the top and to the bottom of the cabinet? Or do you attach it to the wall through a couple studs? And what does the bottom piece do, just extra security?

When you run a screw through from the inside it captures the back and nailer.

I lost you... please clarify, I'm interested in different solutions.

[Yasha Renner]

For cabinets anchored to the wall, I put a 1/4" back in a dodo set in 1/2" from the back edge.

Yep, that is brilliant. Doing this you probably don't even need to use any fasteners.

[Jim Becker]

Just curious, when would this sort of design ever be appropriate? I'm having trouble visualizing it.

This would be the case where, perhaps, wider shelves were physically fastened to the back panel to provide additional strength and weight handling support.

[Mark Hockenberg]

Hi Mark. I'm with you until this... not quite sure what you're describing here. You mean you attach a 1/2" thick piece of particleboard or MDF to the top and to the bottom of the cabinet? Or do you attach it to the wall through a couple studs? And what does the bottom piece do, just extra security?



I lost you... please clarify, I'm interested in different solutions.

Hi Yasha,

Hopefully my sketch will help. The 1/2" thick pieces that I call nailers are attached horizontally flat to the 1/4" cabinet back at the very back of the cabinet. They end up flush to the back edges of the tops, sides and bottoms. So they can be flat to the wall when the cabinet is installed. The top one sits just under the back edge of the cabinet top. The bottom one can be just above the top edge of the cabinet bottom. You can attach these with some glue and small brads angled into the sides, top and bottom OR with small screws from the sides (only if the sides aren't going to show).

The bottom nailer provides a second area to attach screws through to the wall. Normally, when we hang wall cabinets, we use two screws through each of the top and bottom nailers. In your situation, you'd be fine with just the top if your bookshelf sits on the floor.

Cheers,
Mark


Cabinet Back.pdf

[Mark Hockenberg]

Yasha,

Here's a 3-D view that may also help clear up my explanation.

https://www.google.com/search?q=wall...4GCi5C6_YllOM:

Cheers,
Mark

[Yasha Renner]

Ahh, I see now. Thanks Mark, I really appreciate it.

[Yasha Renner]

Here's a 3-D view that may also help clear up my explanation.

Mark, are these the cabinets you build or just an example you found? I was wondering how well the dowels hold up, or if that's customary. I would love to redo our kitchen cabinets some day.

[David Stone (CT)]

On the question of what screws to use, McFeeley's square drive, flat head wood screws in statuary bronze finish are IMO the handiest all-around screws in woodworking and are usually the way to go, unless they don't work aesthetically or would create an anachronism. I'd advocate picking up an assortment of lengths in #6 and #8 sizes to have on hand, though you might need to drop down to a #4 for your immediate purpose if your 1/4 inch back is being let into a rabbet and you don't have as much beef to screw into.

[scott vroom]

I agree drywall screws have their limitations but to tack a non-load bearing cabinet back to a base cabinet, just about any type of suitably sized screw will get the job done including DW. Both my impact driver and drill have a clutch and if set properly will never cause a screw head to pop. That's been my experience, anyway.

While there certainly are many folks who use drywall type screws for non-drywall applications, they are not the best fastener for furniture and cabinet building because they are quite brittle...by design. They are so easy to snap off, especially given most folks drive with an electric powered drill/driver that can exert a lot of torque when the fastener sinks home. In a pinch, well...you do what you gotta do, but I decided a long time ago to just bite the bullet and buy quality screws more designed for woodworking and cabinet making. I use mostly #8 screws, but also keep #6 and #10 for when they are most appropriate. I use # 7 trim heads for my tack trunks which use 12 mm (1/2") plywood as they are primarily for "clamping" while glue does what glue does.

[lowell holmes]

When faced with a decision like this,I will go buy a small package of various screws and epxperiment.

[Mark Hockenberg]

Mark, are these the cabinets you build or just an example you found? I was wondering how well the dowels hold up, or if that's customary. I would love to redo our kitchen cabinets some day.

That photo was just an example I found. My construction is very similar to that diagram. I use the 32 mm system for line boring and use those holes for hinge base plates rather than what is pictured. Since I got a Festool Domino machine, I use Dominos for the connections. I use screws in addition to the Dominos in situations when a finished side is not required. The screws serve as clamps during glue up. Dowels are widely used and certainly acceptable. I've seen doweled joints come apart over time when there is enough stress on the joint. That's why I add screws when they won't show.

[Gary Ragatz]

First question is why 3/4" ply?

All of the plans in the Popular Woodworking document Yasha is using are designed so that you can build the carcase and shelves from a single 4x8 sheet of 3/4" veneered plywood. The bookcases end up 60" tall by 28-1/2" wide and 9-1/2" deep.

If you're happy with those dimensions, and you don't know whether you'll have use for leftover veneered ply, it's probably more cost effective than buying a sheet of 3/4" and a sheet of 1/4".