Cutting foam at home question...

I am trying to make a DIY Full XL sized foam bed, using one of the following links as the base layer:

The problem being that neither is offered in the Full XL size, so my thinking is to get them in the Queen size, and then cut off what I don’t need. I do not have any professional foam cutting tools, but I’ve seen several people online suggest that using a large bread knife works just fine. I wanted to know if anyone has any experience with this and is able to tell me if this is true?

If you are doing it by hand then usually an electric carving knife works best but don’t expect professional results especially when cutting thicker foams.

Alright, well thanks for the feedback, not sure what I’m going to do yet.

Hi NeedHelpPlease.

Mattrebuild is right. The recommendation is to use an electric carving knife if available. To quote DIY Natural Bedding: You could use anything you like, the sharper the blade/finer the teeth, the smoother the cut you will get. You can use a razor blade but don’t be surprised when your cuts are jagged. If you have a knife with a blade longer than the latex is deep you will get a better cut than with a razor blade or box cutter.

Sensei also shared a latex cutting experience here

Ultimately, as long as you aren’t making horizontal cuts to “slit” the foam into a different thickness (which would generally need specialized equipment that you would normally find at a mattress manufacturer, a foam fabricator or supplier, or perhaps a fabric or upholstery store) … it’s not difficult to cut foam to size using an electric knife and all you need is an electric carving knife and a straight edge for a guide and just go carefully and slowly and move the knife in one direction (not a sawing motion). The length of the blade should be longer than the thickness of the layer you are cutting.

Hope this helps you moving forward!

Hi Nikki,

I appreciate the information. I’m leaning towards giving it a go.

I agree with Nikki and the benefit of the electric carving knife is that it’s less prone to get “stuck” in the foam than just using say a normal very sharp carving knife. I don’t suggest a bread knife unless the foam is more rigid because you really aren’t sawing, you’re cutting the foam (sawing motion makes the cut very rough). A long thin very sharp blade (like a carving knife) works best if you don’t go the electric carving knife route. You’ll want to only pull the knife towards you through the foam to cut but you will also have to slightly open the cut area with your other hand (even better to have a helper do this for you). This is so the knife doesn’t bind up as you pull it through the foam. It’s also why I say don’t expect professional results because no matter how careful you are the lines will be a bit wavy and certainly not perpendicular. Although it may not look pretty, it’s not really a big deal unless you are gluing the foam edges together or trying to create different firmness zones in the bed (these situations I would suggest using a proper foam saw if your budget allows).

Interesting, and good to know, thanks!