I have a full size foam mattress that I need to cut smaller to a twin size. I can't think what would be the best tool for the job. I have access to an entire woodworking shop and all kinds of tools but the only thing that seems it might work is a single-sided razor blade. Has anyone done this and can offer any advice? I need to do this asap.

Thanks

-- Elizabeth in e tx (kimprice@peoplescom.net), October 01, 2001

Answers

That sounds like a good way to cut it. I would lay piece of plywood or 1x6 on it, stand on wood to crush it a little a cut with razor,

-- ed (edfrhes@aol.com), October 01, 2001.

A single edge razor blade will work, however, the cut edge will be somewhat uneven. Clamping the foam between two boards helps, but the edge still will be slightly curved.

-- Joe (CactusJoe001@AOL.com), October 01, 2001.

Elizabteh, I think it will be very difficult to cut the mattress and get a neat perpendicular cut, especially if you compress and hence distort the foam in any way as you cut it.

So, a few suggestions, an electric carving knife, a hacksaw blade (push about 3 inches of garden hose on one end to make a handle), bandsaw (but move the mattress very slowly). But my favourite for this job is a hot wire.

-- john hill (john@cnd.co.nz), October 01, 2001.

OK the hot wire sounds intriguing but how do I use it? It sounds like a job for two people?

-- Elizabeth in e tx (kimprice@peoplescom.net), October 01, 2001.

I'm sure a hot wire would work, if you could conveniently rig one up. I don't know how perfect you want the cut on this thing, but I've been cutting R-19 insulation (almost 7 inches thick) quite a bit lately, and the cuts have been straight and quite perpendicular. I take a 2X4 and lay it along the line I want to cut for a guide. Then I kneel on the 2X4, crushing the insulation. Then I use a utility knife to cut the insulation, making sure the blade is good and sharp. With foam, I'd use a brand new blade. Hope this helps a bit.

-- Laura Jensen (lauraj@seedlaw.com), October 01, 2001.

I used to work with an Occupational Therapist who needed to cut foam (1" to 9" thick) for positioning. She would use a regular electric knife.

-- Anne-marie (annemarie@tds.net), October 01, 2001.

Re hot wire.

I made a hot wire cutter. I made a plywood shape, a sort of very deep leter 'C' with two long arms (about 18") and at 8" apart.

The wire I used came from an old clothes dryer but any resistance wire should be useable.

The wire was stretched between the two ends of the 'C' with wires connected from there to a power supply, I found with the wire I used that I needed about 8volts to get the wire just barely red hot. It cuts foam plastic and rubber perfectly.

If you dont have the high current, low voltage power supply like mine than a car battery would be perfect except that that length of wire would quickly burn out at 12V, so just use more wire.

Suggestion, make the wire about 18" long, attach one end to a terminal of the battery and an aligator clip to the other terminal. Start with the clip at the full length of the wire and move it towards the other end to decrease the resistance, hence increasing the current and temperature.

You will use up quite a bit of wire playing with this tool!

Hope this helps.

-- john hill (john@cnd.co.nz), October 01, 2001.

I worked where we made coushions from foam, we used an electric carving knife. You need to mark the center where you want to cut with a marking pen, then stand the mattress on the edge, you will need help holding it. Also make sure the knife is kept stright or you will get an uneven edge.

-- ruby (mcfays451@aol.com), October 01, 2001.

Whenever I've cut foam, I've used a long thin blade, such as a fillet knife for fishing. Just make sure the blade is VERY sharp.

-Chelsea

-- Chelsea (rmbehr@istar.ca), October 01, 2001.

Elizabeth, I would have to go with the electic carving knefe. I did exactly what you did and this worked for me.

-- Ria in Ky (MinMin45@aol.com), October 01, 2001.

Yes, an electric knife works very well. You can also use a regular, serrated bread knife (long blade), but you have to be fairly dextrous to get it to come out mostly even. It will not be perfect.

-- Joy F [in So. Wisconsin] (CatFlunky@excite.com), October 01, 2001.

My sister used to have to cut foam and she said electric carving knife the only way to do it!!

-- DW (djwallace@ctos.com), October 01, 2001.

I used a razor blade- but first heat it up.

-- kelly (kellytree@hotmail.com), October 02, 2001.

Hi Elizabeth,

Electric carving knife gets my vote. It also works good on Angel Food cake!

-- Charleen in WNY (harperhill@eznet.net), October 02, 2001.

We used an electric carving knife to custom fit foam padding for shipping test equipment all the time at the plant. It cuts the foam very cleanly.

-- Jay Blair in N. AL (jayblair678@yahoo.com), October 02, 2001.