How to remove rusty screw

I'm trying to replace the broken hinges on top-opening uPVC double glazed unit. But some of the screws attaching them to the frame have rusted through. I sprayed WD40 but I get no grip at all with my screwdriver. Is there a way to remove the screws without causing damage to the frame? TIA.
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Chris Oates wrote:

Either way, try *tightening* them a tad first, then undoing them.
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Alec wrote:

Assuming they are crosshead, get the apropriate anti cam out rib screwdriver bit and undo them.
MrCheerful
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I thought your spell checker had failed but no - summat I've never heard of http://tinyurl.com/gp4r
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standing on a ladder and my hand on an awkward angle it isn't easy to apply solid pressure.
BTW, what kind of screws do I use as replacements - brass, SS, galvanised? As I live near the sea it doesn't take long for the rust to appear on anything metallic.
Alec
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http://www.mutr.co.uk/MechComp/Mech_screws_nscrew.htm
--
BigWallop

http://basecuritysystems.no-ip.com
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On Fri, 11 Jul 2003 22:47:03 +0100, "Alec"

Diamond paste in oil, sold as "magic screwdriver grip". It's impressively effective.
A good screwdriver bit helps too. I have a Wiha with diamond-plated faces that is handy for awkward ones. They don't last though, so don't use it for "everyday".
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