50mm Drill bit

[Phill Peck]

I have a hole saw, I just don't have one that will go through 200mm of wood. typically they only go about 35mm deep. There does not seem to be such a thing a wood core drill bit for that size.

I have a feeling I am going to end up using a hole saw as deep as it will go, chisel out what is there and repeat.

Your op said 2no 8x2 timbers that's not 200mm. My hole saws will drill a 2" joist remove the core and drill through the 2nd one. Issue is more extending the drill bit.
And then getting your core drill in

 

[Elthrin]

Right 200mm in total including the block, so an SDS extender is what I need.

 

[Nige F]

Diamond core extension from Screwfix -£15.00 And a Starrett holesaw.

 

[Agile]

Right 200mm in total including the block, so an SDS extender is what I need.

The problem is that they don't seem to actually make any SDS extenders!

But you can get pretty long core drill shafts.

 

[DP]

I can't help but picture a Venn diagram consisting of
A- those with structural understanding of timber joists
B-those who have not heard of a holesaw

With @Elthrin standing lonely in AnB

You are very much faster than me on the keyboard
You fail to take into account tools you can carry on a bus

 

[Agile]

Tools on a bus?

I don't see the relevance to drilling a wooden joist.

 

[Gasguru]

A little patience and you can do anything with a core.....

http://media-cdn.tripadvisor.com/media/photo-s/03/49/da/e8/churchill-war-rooms.jpg

 

[durhamplumber]

Why do so many ppl come on..ask advice..then spend days arguing the toss as if they are an expert?????? Bizarre