I am attempting to create plans for converting a regular futon frame and mattress into a slide out style sofa bed using the original parts of the futon, an additional iron twin bed frame, and cardboard (including all glues and related materials for strengthening, upholstering and covering the cardboard).
My question is this: Is it safe to cut into the original futon mattress in order to make it capable of completely folding over itself when converted back into a couch? The mattress feels like it's stuffed with a combination of poly-fill and other recycled fill material.
I don't have a sewing machine and planned to measure, cut, apply fabric glue, and sew (to reinforce the glue) 2 lines about 4-6 inches apart down the center length of the mattress (one at a time to avoid getting the filling everywhere), so that when it is folded into a couch it can fold over to make the bottom support, and when it is opened as a bed the center cut piece isn't noticeable.
My boyfriend is worried that cutting into it and sewing by hand would be too messy and take too long. I disagree since I plan on making everything else first, and doing all of the work on the futon mattress last. We also have 2 foam mattress toppers as well as one of the cheaper toppers with the fitted sheet style edges that I planned on incorporating into the design. The futon mattress offers the most cushion for the bed though. Does anyone else have experience re-purposing an old futon mattress and cutting into it without catastrophic disaster?