Maybe this is obvious but I was surprised how well it worked ...

I was making a heated insulated box (for melting set honey as it
happens) using the rigid expanded polystyrene foam packing from an old
TV as a lining. The padsaw-cut edges were pretty ragged and the
snowstorm of "crumb" stuck electrostatically to every surface.

So I carefully played a hot-air gun over the sawn edges, which melted
down beautifully to a flat, hard skin with very little loss of shape,
and all the loose crumbs shrank away to nothing.

Worth a try if you don't have a hot wire cutter. Don't know if this
works with PU foam.

--
Reentrant

On Wed, 09 Dec 2009 10:40:11 +0000
Reentrant wrote:

Maybe this is obvious but I was surprised how well it worked ...

I was making a heated insulated box (for melting set honey as it
happens) using the rigid expanded polystyrene foam packing from an old
TV as a lining. The padsaw-cut edges were pretty ragged and the
snowstorm of "crumb" stuck electrostatically to every surface.

So I carefully played a hot-air gun over the sawn edges, which melted
down beautifully to a flat, hard skin with very little loss of shape,
and all the loose crumbs shrank away to nothing.

Worth a try if you don't have a hot wire cutter. Don't know if this
works with PU foam.



But a hot wire cutter can be just a length of copper wire from 2.5 t&e
in a wooden handle heated every few mins with a flame (candle will do).

Leckstrickicy isn't always the answer.

R.

On 9 Dec, 12:34, TheOldFellow wrote:

But a hot wire cutter can be just a length of copper wire from 2.5 t&e
in a wooden handle heated every few mins with a flame (candle will do).

I've just cut nearly a hundred yards of inch polystyrene foam
(breadknife) to insulate the shed. Would have taken a long time with a
candle!

TheOldFellow wrote:
On Wed, 09 Dec 2009 10:40:11 +0000
Reentrant wrote:

Maybe this is obvious but I was surprised how well it worked ...

I was making a heated insulated box (for melting set honey as it
happens) using the rigid expanded polystyrene foam packing from an old
TV as a lining. The padsaw-cut edges were pretty ragged and the
snowstorm of "crumb" stuck electrostatically to every surface.

So I carefully played a hot-air gun over the sawn edges, which melted
down beautifully to a flat, hard skin with very little loss of shape,
and all the loose crumbs shrank away to nothing.

Worth a try if you don't have a hot wire cutter. Don't know if this
works with PU foam.



But a hot wire cutter can be just a length of copper wire from 2.5 t&e
in a wooden handle heated every few mins with a flame (candle will do).

Leckstrickicy isn't always the answer.

R.


1800 stlylie

TheOldFellow wrote:

But a hot wire cutter can be just a length of copper wire from 2.5 t&e
in a wooden handle heated every few mins with a flame (candle will do).

Leckstrickicy isn't always the answer.

R.

I needed to remove some chunks from internal corners where I couldn't
use a wire (or angle grinder). The padsaw was ideal.

--
Reentrant

On Wed, 9 Dec 2009 06:09:06 -0800 (PST), Andy Dingley
wrote:

On 9 Dec, 12:34, TheOldFellow wrote:

But a hot wire cutter can be just a length of copper wire from 2.5 t&e
in a wooden handle heated every few mins with a flame (candle will do).

I've just cut nearly a hundred yards of inch polystyrene foam
(breadknife) to insulate the shed. Would have taken a long time with a
candle!

Trying to picture what you did with that .lol..can you explain
further ?

On 9 Dec, 14:31, Usenet Nutter
wrote:

I've just cut nearly a hundred yards of inch polystyrene foam
(breadknife) to insulate the shed. Would have taken a long time with a
candle!

Trying to picture what you did *with that .lol..can you explain
further ?

Making the 8x2 boards shorter and a smidgen narrower, so as to keep
the spacing of the battens between them in synch with the width of the
plywood panels going over the top.

Reentrant wrote:
Maybe this is obvious but I was surprised how well it worked ...

I was making a heated insulated box (for melting set honey as it
happens) using the rigid expanded polystyrene foam packing from an old
TV as a lining. The padsaw-cut edges were pretty ragged and the
snowstorm of "crumb" stuck electrostatically to every surface.

So I carefully played a hot-air gun over the sawn edges, which melted
down beautifully to a flat, hard skin with very little loss of shape,
and all the loose crumbs shrank away to nothing.

Worth a try if you don't have a hot wire cutter. Don't know if this
works with PU foam.

easiest to use a fine sanding block. Shapes EPS foam easily.

On Wed, 9 Dec 2009 07:38:50 -0800 (PST), Andy Dingley
wrote:

On 9 Dec, 14:31, Usenet Nutter
wrote:

I've just cut nearly a hundred yards of inch polystyrene foam
(breadknife) to insulate the shed. Would have taken a long time with a
candle!

Trying to picture what you did *with that .lol..can you explain
further ?

Making the 8x2 boards shorter and a smidgen narrower, so as to keep
the spacing of the battens between them in synch with the width of the
plywood panels going over the top.

Aah I see...That must have been messy ..I have just made a few cuts in
some insulating foam sheets and that was bad enough ...polystyrene
"dust" all over the place . Glad I have a vacuum .

Usenet Nutter
wibbled on Thursday 10 December 2009 11:45

On Wed, 9 Dec 2009 07:38:50 -0800 (PST), Andy Dingley
wrote:

On 9 Dec, 14:31, Usenet Nutter
wrote:

I've just cut nearly a hundred yards of inch polystyrene foam
(breadknife) to insulate the shed. Would have taken a long time with a
candle!

Trying to picture what you did with that .lol..can you explain
further ?

Making the 8x2 boards shorter and a smidgen narrower, so as to keep
the spacing of the battens between them in synch with the width of the
plywood panels going over the top.

Aah I see...That must have been messy ..I have just made a few cuts in
some insulating foam sheets and that was bad enough ...polystyrene
"dust" all over the place . Glad I have a vacuum .

A long time ago, I made a hot wire cutter out of a bit of heater element
wire (then easily available for repairing bar fires and toasters), a car
battery charger and IIRC a big old wirewound rheostat. The frame was just a
few bits of scrap wood assembled crudely into a "U". Worked really well.

Adjustability was a good thing. Tool cool and the wired gunked up. Too hot
and it was smokey and charred the material. Just right and it was perfect.

--
Tim Watts

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