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foam you can carve
jabbahutt - 27/9/07 at 12:55 PM

Hi

I've seen a few photos of what appears to be foam that you can shape. It looks a bit like the stuff surf boards are carved from.

I was looking at using something like this for the lower part of the centre console but haven't a clue what it's called or where to get it.

Anyone any ideas? sorry for the vague description but any help appreciated.

Cheers


Hammerhead - 27/9/07 at 12:59 PM

It's used as insulation in modern building projects. You can get it from big B&Q's think it's manufactured by krauf. Comes with silver on the outer faces that can be peeled off.
Use a dust mask as the fibres are barbed (when seen under microscope) and stick to lungs very well.
About £40 per 4'x8' sheet.


BenB - 27/9/07 at 01:01 PM

There are various type of insulating polystyrene foam. Blue stuff carves and sands much nicer than the white stuff.

In B+Q you can (in some places) buy it without the foil covering. Usually its max 10mm thick but you can bond bits together with glue... the glue doesn't sand or cut well though....

better to get a single piece if its thick stuff you need....


iank - 27/9/07 at 01:02 PM

CFS sell the Ethafoam which is what I think you're talking about. But the PU foam might work OK.

http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__FOAMS___CORE_MATERIALS_14.html


Hammerhead - 27/9/07 at 01:10 PM

quote:
Originally posted by BenB
There are various type of insulating polystyrene foam. Blue stuff carves and sands much nicer than the white stuff.

In B+Q you can (in some places) buy it without the foil covering. Usually its max 10mm thick but you can bond bits together with glue... the glue doesn't sand or cut well though....

better to get a single piece if its thick stuff you need....


The thickness of the stuff at b&q is more like 100mm thickness. I used blue foam at university for making models and its great to shape, I just don't know where you can get thick blocks from commercially. The b&q stuff will probably work ok for you.
And as stated, if you glue two pieces together the glue does not sand (pva adhesive works) like the foam does.


Fred W B - 27/9/07 at 01:12 PM

You want polyurethane foam - like this

Cheers

Fred W B


body 23.5
body 23.5


[Edited on 27/9/07 by Fred W B]


02GF74 - 27/9/07 at 01:18 PM

dunno what the b&q foam is - but if it is expanded polystyrene then that makes one hell of a mess and the little bobules stick ot everything

there is alos the foam in a tube stuff that is not to bad to carve, depends on what you are doing you may be able to make a cardboard former and fill it then shape it but is probalby no so locaost for huge pieces.


BenB - 27/9/07 at 01:22 PM

Oh crapola. Yes 100mm is more like it.
It does bobble (unlike the blue stuff) but this is less of an issue if you use fairly mild sand paper and go by hand.
It hot wires quite nicely..... I made a cheap hot-wire cutter out of an old battery charger and some other bits and pieces. Works very nicely too!!!


Hammerhead - 27/9/07 at 01:28 PM

Guys - at B&Q the stuff from Krauf is very dense and doesn't have bubbles like that crappy packaging stuff. You can sand it cut it carve it it's pretty good.

Looks more like the stuff Fred is using, it's yellow in colour. Many people have used it sucessfully.

Let us know how you get on (with pics)

[Edited on 27/9/07 by Hammerhead]


Fred W B - 27/9/07 at 01:44 PM

It's specced by density - the yellow stuff I am using is 32kg per metre cube.

We presume you are making a plug for a mould? If the shape you want to make has straight flat sections, I recon its easier to make as much as possible from wood and just glue on the foam where you need to make fancy shapes

Cheers

Fred W B


jabbahutt - 27/9/07 at 01:48 PM

thanks for the help, after wandering around B&Q in the past can anyone give me an idea which section I'd find this foam in as asking the staff normally gets you no where. What's it's proper use insulation?


BenB - 27/9/07 at 02:07 PM

Yup. Loft insulation....


BenB - 27/9/07 at 02:09 PM

but the blue stuff is much nicer


Ebay link
[edit]link fixed

[Edited on 27/9/07 by BenB]

[Edited on 27/9/07 by BenB]


westcost1 - 27/9/07 at 02:40 PM

I have used pink foam from b&q it didn’t have any silver foil on it cuts sands easily I made a hot wire cutter and used 2 x mdf jigs ether side to get an exact sape.


Hammerhead - 27/9/07 at 03:05 PM

quote:
Originally posted by westcost1
I have used pink foam from b&q it didn’t have any silver foil on it cuts sands easily I made a hot wire cutter and used 2 x mdf jigs ether side to get an exact sape.


As an aside, how did you make the cutter?


BenB - 27/9/07 at 05:12 PM

I made one very cheaply using a broken old battery charger. That had a nice powerful transformer in it, an dc amp gauge and a charging IC.

I got a dimer switch and stuck it on the side of the charger casing, I chopped the wire going from the charger mains power fuse into the transformer and fed it via the dimmer switch. The transformer output I fed through a bridge rectifier and into the amp guage. I let the juice flow through the crocodile clips as when it was a charger.

I got some nichrome (resistance) wire from Maplins to use as hot-wire and made up a frame to hold a nice length of it. Heated it up nice and quickly (voltage adjustable via the dimmer switch).

Obviously doing the above modification needs care and attention cos we're talking 240v AC here and if you're not sure what you're doing don't do it.

But I think all in all it cost me a broken battery charger (the charger IC had bust) and about 5 quid....

Strictly speaking you don't need to have a rectifier but if not you'll have to by-pass the current dial (which is designed for DC) and being able to see how many amps you're pulling is useful for setting up the cutting wire as its the current that controls the heat....

Go nice and slowly to avoid judder (and wax the edge of the MDF formers if you need super smooth)...

[Edited on 27/9/07 by BenB]


trextr7monkey - 27/9/07 at 07:50 PM

A bit late I know but we've use both the blue styrofoam (high grade model making /prototyping stuff) as wellas the yellow stuff (off cuts from builder- cheap but incredibly dusty and hazardous to breathe in .
Syr foam is available from all of the usual educational technology suppliers - trendy to use it for rapid proto typing on cad cam machines as the tools never wear out!!
try
technology supplies
Techsoft
Denford
K and M Supplies; sheffield
Rapid Education
Middlesex University TEP
Suregrave - engraving suppliers etc

There's a firm called Clarke - not machine mart guys , in Wales who make line benders, hot wire cutters seperately and combined and vac forming machines - stuff does turn up on e bay .
Alternatively visit a local secondary school