best methof of cutting foam?

[[2574]]

I've some thick foam that needs trimming (mattress); what's the best way of cutting it? Bread knife? Carving knife? Tenon saw?

 

[BobPrell]

Bread knife way better than carving knife.

Maybe try tenon saw for straight lines.

 

[john_morris_uk]

I successfully cut some once with an electric carving knife (remember them?)

Don't the suppliers cut them with hot wire knives? Can you get a foam supplier to trim it for you? It would take seconds and cost you a bottle of something or a very few £.

 

[ianfr]

I use an electric carving knife, which is no longer in kitchen use. Just need to cut steadily and carefully.

Regards

Ian

 

[ghostlymoron]

I too use an electric carving knife but it's true that commercial suppliers use a hot wire. I've thought about making the latter using some thick fuseewire powered by 12v battery. Would need some experiment on wire size (or calculation)

 

[srp]

Can't imagine using a tenon saw. I always use a bandsaw as it gives a much more accurate cut than any other method. The pro's use a scalloped blade but that's too much expense for the odd job, so I just use the blade that I normally use, a 3tpi skip tooth. If you don't have a bandsaw then you have to make do with a carving knife. Hot wire is frowned on nowadays because of the fumes given off.

 

[Buck Turgidson]

I too use an electric carving knife but it's true that commercial suppliers use a hot wire. I've thought about making the latter using some thick fuseewire powered by 12v battery. Would need some experiment on wire size (or calculation)

0.12 gauge guitar string is the normal weapon of choice for hot wire cutters but beware the fumes!!

 

[TrueBlue]

I use a bandsaw, but not a lot of use if you haven't got one OR you're cutting more than 8" off.

I sometimes have success with a Stanley knife (a bit tedious) - perhaps you can get a variant with a long blade (not toothed) ??

 

[Bobobolinsky]

Never heard of urethane fire proof foam being cut by hot wire. I cut polystyrene foam with a hot wire bow saw, though I have seen it cut with a tension saw with handle on either end, cut over a former, quite skilled work.
Usual method is bandsaw, I use an electric carving knife, bought at auction for 50p.
I did have a Bosch tailors saw, which is the real Mccoy.

 

[vyv_cox]

Dunlopillo/Aeroprene cut all their foam with bandknives when my wife worked for them. We have not come across foam cut with hot wire but I have cut polystyrene with one many times. Electric carving knife is the usually quoted method but we do not own one and use scalpels.

 

[prv]

Electric carving knife all the way. Bloody ridiculous device for the kitchen, brilliant on foam.

Only problem I had was that the cheapest seller was the QVC website, so now it looks like I watch daytime telly

Pete

 

[ianat182]

In the past I've used a carving knife wetting the blade with detergent to keep it slippery;spraying with silicon/teflon may do the same; rather a slightly serrated edge than razor-sharp.


ianat182

 

[VicS]

For small jobs like just trimming a sharp kitchen knife will do it but electric carving knife is just about the ideal tool for larger jobs such as cutting whole new cushions, except that decent suppliers will cut to a template.

 

[ghostlymoron]

0.12 gauge guitar string is the normal weapon of choice for hot wire cutters but beware the fumes!!

i've got plenty of old guitar strings. 0.12 is a heavy top string I believe. Just attach to car battery?

 

[JSYmartini]

Electric carving knife is the reccommended way for cutting foam in Peli cases etc

 

[LadyInBed]

Only problem I had was that the cheapest seller was the QVC website, so now it looks like I watch daytime telly

My Electric carving knife was sourced from one of our local charity shops
so it now it looks like I do my shopping in charity shops - I do, I do

 

[VicS]

I though the objection to using a hot wire for cutting upholstery foam was the possibility of producing toxic fumes .

 

[Stemar]

I recently did the deed for forepeak mattresses with a hardpoint wood saw. It does the job, but you wouldn't want the cut edges on display.

30-odd years ago, I worked in a furniture shop and we'd cut foam with an electric carving knife. It's easy to get it OK, but quite skilled to get clean square edges.

 

[coliholic]

I cut quite a lot of foam for model aircraft wings and fuselages using a hot wire bow and it works fine. I cut both white polystyrene and blue insulation foam and the bow works fine. For quick cuts I use it on 24v and it's surprisingly quick, for more intricate carving I connect it to just one battery charger, so 12v and it gives a bit more time to do the job. fumes can be a bit eye watering so do it in thje garden or with the door open.

Never tried the electric carving knife, that's reserved for the Sunday joint. Why do you lot sneer and turn your noses up at them? Am i missing something here?

 

[prv]

Never tried the electric carving knife, that's reserved for the Sunday joint. Why do you lot sneer and turn your noses up at them? Am i missing something here?

If the Sunday joint is so tough it needs a culinary chainsaw to cut it, the solution is better cookery rather than power tools

Pete