Drilling with 6mm drill for 6mm bolt

[richard7761]

Hi. I need to get some "long series" hss twist drills (capable of cutting through thin metal sheet). About 150mm long-ish.

Basically, the drill needs to cut through a 100mm wide beam (and on it's way also thru two sections of thin metal sheet).

Okay: If I use a 6mm drill for a 6mm coach bolt, will I be able to pass the bolt through the wood with reasonable ease?

Or will I need a 6.5mm drill bit?

Thanks.

 

[Burnerman]

A 6.5mm drill will make life so much easier, Richard!
John

 

[richard7761]

A 6.5mm drill will make life so much easier, Richard!
John

Hi. Okay, I should go for one bit, size 6.5mm and not for a pack of them of 6mm.

 

[Burnerman]

I'd always have more than one drill, and I'd also drill a pilot hole first, just to help things along.
Plenty of lube and low speed should see you through ok.
What depth of metal are you talking about here?
John

 

[richard7761]

I'd always have more than one drill, and I'd also drill a pilot hole first, just to help things along.
Plenty of lube and low speed should see you through ok.
What depth of metal are you talking about here?
John

Hi. Drill needs to go thru 2mm mild steel, twice, because there are two thin sheets to cut through. And of course 100mm wood (actually two 50mm beams side by side).

I was thinking buying something like a Faithfull PP650LS for a 6.5mm hole.

 

[richard7761]

This is the situation:

Untitled

• richard7761
• 4 Apr 2015
• 2

 

[richard7761]

Beams on left (out of sight) and right.

I'm bolting those joist hangers. Getting rid of the top bend overs.

Leaving in the original nails holding the hangers and adding bolts.

 

[Burnerman]

I see....Through the first strap, then the timber and then through the other strap?
It may prove difficult keeping the drill level, but good luck with it!
John

 

[Norcon]

No need for drilling through. Just stick a screw nail in.

 

[richard7761]

No need for drilling through. Just stick a screw nail in.

I need to remove those bend over metal strips. Otherwise I'll not get the new floorboarding to match level.

 

[richard7761]

I'm not a structural engineer, but I cannot see those hangers failing (given the nature of loading) if I remove the strapovers and use two bolts (on each side) to hold the hangers.

 

[Norcon]

Notch the joist slightly and recess them. They should hammer in to place.

 

[richard7761]

Notch the joist slightly and recess them. They should hammer in to place.

Yep, I could do that.