How to Build a Flat, KWLT Style

KWLT uses flats known as ‘hard’, ‘traditional’ flats. This means they are build with the lumber flat, not on edge (flats built with the lumber on edge are ‘hollywood’ style flats) and faced with luan plywood (flats built with muslin covers are called ’soft’ flats). Flats can be any dimension, but the standard for KWLT is 4′ wide by 8′ tall. We also stock 2′x8′ flats, as well as 4×8 flats pierced for doors and windows. KWLT flats are built using 1″x3″ material (sold as ’strapping’ in hardware stores). Pick straight pieces when purchasing the lumber. 1/4″ Luan plywood is used to face the flats. Some stores call this ‘doorskin’. Locally to KW, Swanson’s Home Hardware stocks this material. You will also need material to make corners and keystones/tabs - thin scrap ply, hardboard, I’ve used all of these.

Materials

To build a KWLT Style 4×8 Flat, you need :

• 2 Rails (bottom and top) * 1×3x4′
• 2 Stiles (sides) * 1×3x7′7″
• 1 Toggle (middle) * 1×3x3′7″
• 4 corner pieces * right angle triangle of scrap, cut 6″x6″ approx.
• 2 Tabs * rectangle of scrap, cut 4″ by 6″ approx.
• 1 cover 4′x8′ full sheet of 1/4″ luan

An ideal surface to build a flat on is a 4′x8′ table, such as one made with a pair of sawhorses and a 4×8 3/4″ plywood top. If that isn’t available, any large, flat surface will do.

Flats are held together with glue. The easiest way to clamp the wood in place is to use a pneumatic nailer/stapler and narrow crown staples. I own one of these, so that’s what I do. Small screws can be used instead, if necessary.

The Assembly
Lay out your 1/4″ luan. Start with a 4′ rail, cover one flat side with glue and lay this across the bottom of the luan, flat side down. Slide this edge of the laun off the edge of your work table and attach luan to rail, using either staples or small screws. Be careful not to break the laun, it is thin.

Cover one flat side of a stile with glue and put into place along one long edge of the luan. Attach as with the rail. Cover one side of a corner block with glue. Use the corner block to reinforce the join between the stile and the rail. Make sure that the corner block is at least 3/4″ from the outside edges of the flat. Attach with screws or staples, at least two into the rail and two into the stile.

Repeat for the other stile and the other rail, placing corner blocks at each corner.

Cover a flat side of the toggle with glue and place it in the middle of the luan, running from stile to stile. Cover a tab with glue and place it over the join between the stile and the toggle, making sure that the tab is at least 3/4″ from the edge of the flat. Attach with staples or screws, making sure there are two screws in the stile and three in the toggle. Repeat on the other side.

Wait for the glue to dry… and that’s all there is to it.

Note 1 : The sketchup file used to create the picture of the flat is available.

Note 2 : In traditional flat building, a shaped piece called a ‘keystone’ is used to attach the toggle on each side. A ‘tab’ works just as well and is a lot easier, so that’s what we do at KWLT, but if you want to use a keystone, you can.

Note 3 : Traditionally, the rail is always the full width of the plywood, with the style being cut to fit between the two rails. This is so that there is no joinery where the wood meets the stage floor. A few KWLT flats don’t follow this rule. You live, you learn.

Note 4 : Many of KWLT’s flats use 1×4 instead of 1×3 - either is fine. 1×3 is cheaper. If you use 1×4, you will need to adjust the toggle and stile lengths.