How to make 60mm holes in new sleepers ?

[brightspark]

Forstner bit is the only doable modern option. You will struggle to find one with a long enough shank though.

With a bit this size, a normal drill will be bu**ered in short order though.

You say "new sleepers", so does this mean large bits of tanalised softwood, or proper hardwood sleepers, which will be tar impregnated ?

What you really need is a good old fashioned wood auger with a tee handle, which they used to make old timber framed buildings, or failing that a Brace, with a square shank bit

thats why my arms are knacked now allways gave the apprentice to do it had muscles like popeye once

 

[Smallfry]

Good suggestion by Blue Chips. Might get away with that. I find these bits too aggressive, and power drills are a bit too fast, and if it jams, it can hurt you wrist, or worse. Also I find that if they go out of line, they are almost impossible to realign.

The OP only has 263 holes to drill

 

[Kram]

Could you link to a supplier who offers them in the required 60mm diameter?

Expensive but they do them upto 64mm

https://www.amazon.co.uk/IRWIN-IWAX2007-Self-Feed-Speedbor-Supreme/dp/B09G8VLNF5/

However given it needs to pass 48mm a cheaper 2" would do it. Op has not said why he wants 12mm clearance on the scaffold bar

No more dangerous than a 9" angle grinder, it's the muppet using them incorrectly that's the problem......

I'd happily use my 020t, g372xp or say, 3120xp all day long. Safe if you know how to use them. Wont find me anywhere near a 9" grinder.
I did shatter a tiny 10mm die grinder stone today if that counts, hit me on the cheek but no damage.

 

[brightspark]

the speedbor goes up to 50mm

but theres another type as well 57mm it does the same thing

https://www.amazon.co.uk/IRWIN-INDUSTRIAL-TOOL-Self-Feed-Drill/dp/B001VND728

a cutter that size needs a bloody good sized motor drill about 1500 watts with a clutch and reverse when it grabs it will take you round with it . an old wolf gutbuster would work well with extended handles and 2 people