Intro: King Platform Bed From 2x4's and Plywood
The purpose of this instructable is to construct a king size platform bed using 2x4's and plywood. This bed will be going into a smallish bedroom, in order for everything to fit comfortably the platform bed must be no larger than the mattress. Since closet space is also limited the bed will incorporate 4 drawers for additional storage. Overall cost for this build was around $100 including drawer slides I ordered online but have not yet used.
Step 1: Materials
(11) 2 x 4 x 8' Construction Lumber
(1) 5/8" BCX Plywood at least 4'x4'
(2) 1/2" 4' x 8' Sheets OSB
(1) 1/2" Dowel Rod (Optional)
3" Construction Screws
2 1/2" Pocket Hole Screws
Step 2: Cut Seven 72" 2x4's
Cut Seven 2x4's at 72"
- This Yields Seven 72" and Seven 24" 2x4's
Step 3: Cut Eleven 11" 2x4's
- Using the 24" scrap from step two, cut eleven 11" 2x4's. The 7th 24" board from step 2 can be set aside for use later.
Step 4: Cut Four 78" 2x4's
Cut four 2x4's down to 78"
This yields four 2x4's 78" and four scrap 2x4's 18"
Step 5: Remove the Rounded Corners
- Adjust the rip fence on your table saw to 3 1/4"
- Remove 1/4" from each of the following 2x4's as pictured (7) 72", (4) 78", (11) 11"
- Adjust the rip fence on your table saw to 3"
-Remove 1/4" from the opposite side of each of the 2x4's listed above.
- The yield from this step is: (7) 1 1/2" x 3" x 72" , (4) 1 1/2" x 3" x 78", (11) 1 1/2" x 3" x 11"
Step 6: Select the Best
- Out of your (7) 72" boards select the best two to be used on the exposed portion of the bed and set aside the five remaining boards to be used as mattress supports.
- Now is a good time to clean up the scrap pile (pictured)
Step 7: Assemble the Sides and Foot of the Bed
Time to assemble!
I pre-drilled and countersunk 3" screws for the assembly, screwing the boards together from the top and bottom edges. If the holes bother you, they are easily filled in with dowels and a little wood glue.
Step 8: Route a Ledge for the Plywood Panels
- You could put plywood panels in all 8 openings, however I chose to leave four open to have drawers installed later.
- I used a 1/2" x 1/2" router bit in multiple passes to make a slot 5/8" deep and 1/2" wide.
- Square off the corners with a hand chisel so the plywood panels will fit in place.
Step 9: Cut Plywood Panels
- Cut plywood panels to fit the recess we cut in the previous step.
- If you are installing four panels instead of 8 like I am, you will need to cut (2) panels 32 1/2" x 12" and (2) panels 23" x 12"
Step 10: Install the Plywood Panels
- Apply a bead of glue and tap the panels into place.
- Secure with 1" brad nails
Step 11: Use 2x4 Scrap to Make Corner Braces
- Cut one of the scrap 2x4's to 16"
- Cut the 2x4x16 into two 1 1/2 x 1 1/2 x 16" corner braces
- Clamp the side frames and the front frame together and attach using the corner braces made above and (16) 2 inch screws
- The top of the corner braces should be exactly 1/2" below the top edge of the panels, this creates the ledge that our OSB panels will sit on.
Step 12: Rip Additional Bracing
-Using your table saw rip one of the 1 1/2 x 3 x 72 into two 1 1/2 x 1 1/2 x 72
-Shorten one of the 1 1/2 x 1 1/2 x 72 boards 69"
-Using 2" screws, Install the 69" board on the front panel exactly 1/2 inch from the top edge, this will support our platform at the foot of the bed.
- Cut two 1 1/2" x 1 1/2" x 27 1/2" boards out of the other 72" board. Set aside the scrap from this board for use in the step 14.
- Using 2 inch screws install these 2 inches from the top of the side panels at the very back of the bed, these will support the 2 rear mattress supports.
Step 13: Install Two Rear Mattress Supports
Attach the two rear mattress supports to the 27 1/2" boards you installed in the previous step.
The spacing I used for the mattress supports is roughly 18 1/2 inches on center.
Step 14: Cut the Front Mattress Support Brackets and Install the Front Mattress Supports
**To build a better bed skip this step in its entirety and use some 1 1/2" steel angle iron to secure the front mattress supports to the side panels.
- Using the scrap from step 12 cut 4 boards 3/4" x 1 1/2" x 8"
- Drill 3 holes as pictured in each of these
- Remembering our 18 1/2" on center spacing attach these 8" brackets to the side panels using 2 1/2" Kreg pocket hole screws. I used pocket hole screws because the flat bottom on the head of the screw was less likely to split these small boards.
- Drill 4 pocket holes in both of the remaining 1 1/2 x 3 x 72" mattress supports as pictured.
- Position the last two mattress supports on top of the brackets we installed above.
- Using 2 1/2" Kreg pocket hole screws attach the (2) front mattress supports to the side panels.
Step 15: Review
At this point your assembly should look like the image above.
Step 16: Cut OSB to Fit the Platform
- After making sure the frame is square you should find that you need plywood to cover the top measuring 72" x 76"
- Cut two sheets of 1/2" OSB to 38" x 72" after verifying that your mattress supports will fall directly under the seam.
Step 17: Cut and Edge Band the Plywood for the Drawers
- I will be making four drawers to fit this bed in separate instructable, however since I will be staining the bed I want to prep the drawer fronts and stain them at the same time I am staining the bed.
- The openings for the drawers measure 11" H x 22" W
- I know I am going to apply edge banding that is 1/8" thick to all edges of my plywood and I know that I want approximately a 1/4" gap all the way around my drawer after the edge banding is applied so that it fits nicely into the opening.
- Based on this plan I cut my (4) drawer fronts to 10 1/4" x 21 1/4"
- The edge banding I used, was made from the thin rips removed from the original 2 x4 's to produce 1 1/2" x 3" stock. Basically the edge banding would have been fit for no other use except kindling.
- I applied the edge banding a little long and sanded it smooth as shown in the pictures.
Step 18: Apply Finish
I found it best to disassemble the bed and stain each component individually, besides, I needed to disassemble the bed to get it inside my house.
I stained the bed with just one coat of Minwax Water based stain and applied 3 coats of Minwax waterbased polyurethane stopping to sand between the second and third coat with 800 grit sand paper.
There is no need to stain or seal the inside components that will not be seen, but the side panels and end panel and both sides of the drawer fronts should be done at the same time.
Step 19: Assemble and Enjoy!
In review this bed is maybe 2 inches taller than I would have liked, I am a short person at 5'9" and I can get on and off just fine but it is a little taller than my previous setup.
- Drawers will come when spare time suddenly appears, for now the bed is usable.
- Also noteworthy is that the rough surface of the OSB does present some annoyance when changing sheets, I might have to make time to put a coat of poly on those boards as well.
- I would also 45* angle the ends of the foot board if I was to do this project again as the mattress is naturally rounded at the corners and the bed is a solid 90* angle.