Help - cutting 8" foam?

Old 08-29-05, 12:13 PM
Visiting Guest
Posts: n/a
Help - cutting 8" foam?


I want to cut a double bed all-foam (no inner springs) mattress down to fit a small antique day bed. What type of tool can I use to cut thru @ 8" of foam to reduce a 56" x 72" mattress to 30" x 70"? Thx. Clare
Old 08-29-05, 12:17 PM
Join Date: May 2005
Location: Northeast, US
Posts: 129
Upvotes: 0
Received 0 Upvotes on 0 Posts
Do you have an electric kitchen knife? Like the kind you'd use to cut the Thanksgiving turkey? Those work really well for cutting foam!

Sans that tool, what about any type of small hand saw? Do you have anything like that?
Old 08-29-05, 11:50 PM
Join Date: Aug 2004
Location: Vancouver, Canada
Posts: 1,126
Upvotes: 0
Received 0 Upvotes on 0 Posts
You can shred through foam with serrated tools.

But a clean cut is not difficult either, with a sharp knife (e.g. utility knife AKA box cutter) and the right technique.

1) Lay the foam flat and use a straightedge and felt pen to mark the cut line.

2) Place the cut line over and in line with the edge of something (like a railing or bed frame) so the foam can be bent away from the blade as you cut. This will keep the blade from binding in the foam, that producing a stuttered or torn cut. It helps to use a board or such to form this bend and hold it while cutting. An extra set of hands is good too.

3) Tilt the blade to one side if necessary so that it always points through to what was the opposite side of the foam when flat. For example, if you've bent the foam 90 degrees then the knife should be at 45 degrees. Do not saw. The stretched foam will easily part with very light full-length passes. This is where it becomes confusing - the foam changes shape as it springs apart. Just hold the foam at the same bend, though, and don't try to compensate with the knife, the cut will work out.

That 2" cut off will be difficult. Again, the cut line needs to be pulled open, but there just isn't much to grab. I think this one will be easier with the foam laid flat, and the friction of a board used (by a helper) to separate it in cutting. Press the board down enough it doesn't slip, and pull. The knife would not be tilted in this case. Do the easy cut first for practice.

You might also consider marking both sides, and cutting from each to meet half way.

Enjoy. If done right, foam cutting feels like magic.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: