Hi all

I need to drill two holes on the flat side of this clamp

they also need to be countersunk from the inside...

what is the best drill bit / countersink to buy?

im a bit concerned about countersinking as you can see from the dimensions... the width of the channel isnt very wide to get a c/s bit in to

(I am screwing this bracket to the ceiling and want the screws flush in to the clamp)

you cannot countersink the inside without making a special tool and several hours even then how do you insert and do up a screw??
if drilling a large hole in the opposite side off the bracket is not an option
best idea is use a tap to put a thread then use threaded rod or bolts from the other side as in through the structure into the bracket

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we are all ------------------still learning

Do you mean the short side? What is the material, is it aluminium? If it is then you would get by with HSS bits and a woodworkers countersink I would think.

DWD

I would use an 8mm or 6mm drill to countersink with, ideally one the same size as the screw head you are using.
Don't go tooooo far or there will be very little material to hold the screw.



John

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Growing old is compulsory, growing up is not!

You can get countersinks in various sizes, easily get one that would fit between, but shank length would be a problem i imagine.

You can also get clamps like that with holes ready drilled in them ;)

In this instance, you need to get yourself a half decent HSS bit, the size you want, And one about the size of the head of the screw.

As above, take it steady on the second, Very easy to drill right through.

Ideal you would grind the end of the larger drill to 45 degress to suit the screwhead, but its not worth the effort. Use it at the 60 it is.

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Why isn't the number 11 pronounced onety one?

Where would I get a ready drilled clamp hitch? Must clamp 10mm glass

Have a look here: http://www.crlaurence.co.uk

If you got a grinder that's what I'd do...only takes a few minutes. I'd also knock off the edge a bit otherwise the drill might be a bit keen and grab.

Failing that, just use a normal drill which matches the size of bolt/screw head you're using, as Hitch suggested.

wrinx

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www.ilmostro.co.uk

Or here-

http://www.parkertools.co.uk/Group/QRA/Q-Railing

This sort have a removeable pin too, so the glass cannot slip out....

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Why isn't the number 11 pronounced onety one?

To get the drawings for them, you may need to cross refference with this site-

http://shop.q-railing.com/ts/en/glass-c ... ess-steel/

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Why isn't the number 11 pronounced onety one?