Expanding an existing bed frame to accommodate a queen, king or California king mattress requires more than simply moving the sides apart. Many mattress companies void the warranty if your bed frame does not have a rigid center support. A high-speed steel drill bit turns adding a removable center support into a 10-minute job. A welder creates a permanent bond between the rigid center support and the bed frame, but requires more time and a safe workspace.
Things You'll Need
- 3/8-by-80-by-2-inch wide steel bar stock
- 3/8-by-84-by-2-inch wide steel bar stock
- Carpenter's measuring tape
- Soapstone marker
- Small C-clamps
- Wraparound eye protection
- Ear protection
- Power drill
- High-speed steel, titanium-nitride bit set
- 3 bed leg assemblies, with hardware
- Welding gloves
- Welding helmet and full leathers
- NIOSH-approved respirator
- 110-volt gasless MIG welder
- 2 pieces 3/8-by-60-by-2-inch wide steel bar stock
- 2 pieces 3/8-by-76-by-2-inch wide steel bar stock
- 2 pieces 3/8-by-72-by-2-inch wide steel bar stock
- 4 bolts with matching hex nuts, 1/4-inch thread diameter
- 8 fender washers, 1/4-inch hole
Adjustable Metal Frame
Remove the mattress and box spring and move the bed frame to a metal shop, garage or outside. Set the frame up without the mattress and box spring. Stand inside the bed frame at the headboard end, facing that end of the frame.
Use a soapstone to mark the center point between the left and right sides of the frame, along the ceiling face of the head end of the bed. Repeat that same mark at the foot end of the bed.
Use the soapstone to mark the center point on each end of the correct-length steel bar, one inch from each end and one inch from the left and right sides. Use an 80-inch-long bar for a queen or king center support and an 84-inch bar for a California king center support.
Center the steel bar on the marks you made on the bed frame. Use the soapstone to mark the position of the steel bar at both ends of the frame. Secure the steel bar at the foot end of the bed, using a C-clamp.
Place one of the leg assemblies upside down on the head end of the steel bar. Mark all screw positions using a soapstone. Set the leg assembly aside.
Don ear protection and wraparound eye protection. Drill all the necessary holes for the leg assembly. Secure the leg to the underside of the frame -- using the manufacturer-supplied hardware -- with the bolts going through the steel bar and the frame before going into the leg assembly.
Remove the C-clamp at the foot end of the bed frame. Repeat steps 4 through 6.
Mark the center point between the head and foot of the bed frame, along the center support you just installed. Place the third leg assembly upside down on the center support and mark all the screw positions.
Drill all the holes and secure the center leg to the center support using manufacturer-supplied hardware. Replace the mattress and box spring after returning the bed to the bedroom.
Remove the center support and legs when necessary to move the bed back into the house or any time you move to another residence.
Metal Side Rails Only
Install head and foot crossmembers. Use 60-inch-long bar stock for queen-size bed frames, 76-inch-long stock for king frames and 72-inch-long stock for California king frames. Lay a crossmember from the left corner of the frame at the head of the bed to the right corner.
Drill two bolt positions one inch apart at each end of the head cross member, one inch from the right and left ends. Place a fender washer on each bolt and push them through the four holes.
Place a second fender washer on each bolt and secure it with a matching hex nut.
Repeat steps 1 to 3 for the foot crossmember. Attach the center support to the head and foot crossmembers using the same procedures you used on the head and foot of the adjustable metal bed frame.
Tips & Warnings
- The rigid center support must have at least one leg for a queen set and at least two legs for a king or California king mattress set.
- If your doors and hallways are tall and wide enough that it will never be necessary to disassemble the bed frame, you can weld the center support to the frame using 45-degree fillet welds.
- Use the recommended steel thickness, as anything thinner may bend during use and anything thicker may damage the ends of your box spring.
- Always wear both your primary eye protection -- wraparound safety glasses with side shields -- and your welding helmet at all times while operating a welder or while assisting or observing a fellow worker. Do not weld on galvanized, lead- or metal-plated steel due to the risk of producing toxic fumes. Metal fume fever can be fatal. Symptoms of metal fume fever include flu-like symptoms, cough, dyspnea or difficulty breathing, adult respiratory distress syndrome and death resulting from delayed pulmonary vascular fibrosis.
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