What size drill bit (mm or inches) to drill the lugs?

[GarrettP1]

I want to drill my lugs on my 1655 Explorer case. Several good "how to" articles are available,

but I wasn't clear on the size of the drill bit.

Does anyone know?

Thanks,

Garrett

[JoeyB]

1.3mm

[GarrettP1]

Thank you. That was fast!

[alligoat]

Snap-On #55 works pretty well- PN- DBCE55A.

[FxrAndy]

I use 1.3mm

[username here]

is that true of all lug holes? i.e. GMT, sub, Explorer II- all 1.3?

[alligoat]

I think so and also Explorer I

[JoeyB]

is that true of all lug holes? i.e. GMT, sub, Explorer II- all 1.3?

The Date-Just is smaller, 1mm.

[Omega]

We had a discussion here about it! I can guarantee, you can NOT push a 1,2mm drill into a gen lughole! I tested it a several times!!! So it is definitly smaller than 1,2mm! Don't ruin your case...

But 1,2mm is OK, it's not visible. Lugholes drilled with 1,3mm you can spot easy (even with a nacked eye), because the springbar has not tide fitting!

[preacher62]

is that true of all lug holes? i.e. GMT, sub, Explorer II- all 1.3?

Everthing that uses the 2mm springbars.

[FxrAndy]

We had a discussion here about it! I can guarantee, you can NOT push a 1,2mm drill into a gen lughole! I tested it a several times!!! So it is definitly smaller than 1,2mm! Don't ruin your case...

But 1,2mm is OK, it's not visible. Lugholes drilled with 1,3mm you can spot easy (even with a nacked eye), because the springbar has not tide fitting!

Below in the attached photo is my 1978 gen sub with a bit of 1'2mm steel stuck through the lugs and it is loose. In fact a 1.3mm drill bit fits in but is very tight.

If you look at my comparison post between the rep and gen you will see there is almost not visible difference between the gen and the rep in terms of lug hole size on a vintage worn watch and a rep that is supposed to be a vintage watch, they may well have been 1.2 or less when new but they are not new any more

To save you the time i will repost a photo here

gen is on top by the way

[Omega]

Andy, I don't want to discuss anymore about it. I own several of gen vintage watches and every month also a lot go thru my hands for overhaul. Use the upper side of the drill and try to put it in the hole. If it works your holes are dead!