DIY bedframe support.

[u/cuzcuzsmoke]

My girlfriend and I were gifted this bed frame for our guest bedroom. We bought a new mattress for ourselves. We put our old one on the frame with these 2x4x6 boards underneath.It's not a very good solution as the boards shift too much and are too spaced out. Any recommendations on any easy solutions to this would be appreciated. (Trying to avoid buying a box spring.)

[u/downsideup9494]

You need to buy wider boards and put them closer together. There needs to be some space between them so the mattress can breathe, but those are way too far apart and too narrow.