Advice on installing frame anchors in PVCU doors please.

I'm about to install some PVCU (plastic) French doors from Wickes and I'm not sure about how to go about installing the frame anchors.
The anchors are 8mm diameter so I need to make an 8mm hole through the door frame to accommodate them. The problem is that the hole will go through the steel frame inside the plastic frame as well and I'm not sure whether I should start with an 8mm HSS bit and just try to make the hole in one go, or would it be better to use a pilot HSS bit of smaller diameter first to stop the larger 8mm bit wandering?
Anyone have any experience of doing this? What should I do?
Thanks for any advice.
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On 11/05/2011 22:18, clangers snipped-for-privacy@yahoo.co.uk wrote:

Having drilled hundreds of thousands of holes through anything that can be drilled, by hand with a power tool, I would put in pilot holes first. Start off with 2.5mm and increase to 5mm. The 8mm drill will follow these holes ready for your masonry drill to follow into the wall. Just be gentle and ensure that you don't put the pressure on the drill from the pistol grip, but just use the handle to access the switch and put lots of pressure on the back of the drill. Just make sure the drills are sharp. If you had started with an 8mm drill, who knows where the hole will end up in the frame. You can grind a drill, can't you?
Dave
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SNIP

You should have asked if the OP can grind a drill PROPERLY
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On 11/05/2011 22:18, clangers snipped-for-privacy@yahoo.co.uk wrote:

Bosch multimaterial bit straight through the lot works quite well IME. (it may not be long enough to drill the full depth in the masonry - but it will serve to start the hole off if nothing else.

Use packers to keep everything square, keep testing as you tighten things up. Once its all sat square you can foam it in place. You don't need that many frame anchors in total - say three per side and depending on width one or two along top and possibly bottom.
Remember the opening bits derive much of their rigidity from the way the glass is fitted. You want the plastic packers to brace the glass in the rebate so that it acts like a restraint to the door drooping.
--
Cheers,

John.

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aye heel and toeing
http://www.malbernwindows.co.uk/trade/toeandheel.html
links too!!!
Jim K
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