Countersink drill w/ depth stop, 3.5mm 492523

[harry_]

I would like to know the maximum drilling depth before countersinking?

 

[AlexThePalex]

38 mm.

 

[harry_]

arg! I was hoping for another 1/8th of an inch or so  [sad]

 

[Daniel_n]

How about changing to a longer 3,5mm drill bit?

 

[harry_]

That's always a possibility I suppose?

 

[AlexThePalex]

Unfortunately it is not that easy to place just any drill bit in it. The Festool bit has a machined plane on the shaft to accommodate the tightening screw. If you put in a normal drill bit with a round shaft it will not be centered. I have experimented with this. However, I succeeded to machine the plane on a normal drill bit with a Dremel and a special router bit for metal. So with a bit of work you can make it happen.

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It sure is a big annoyance that all Festool drill bits are too short, be it wood, metal or countersinks. I don't know why they did this but it is irritating to say the least.

 

[Daniel_n]

Unfortunately it is not that easy to place just any drill bit in it. The Festool bit has a machined plane on the shaft to accommodate the tightening screw. If you put in a normal drill bit with a round shaft it will not be centered. I have experimented with this. However, I succeeded to machine the plane on a normal drill bit with a Dremel and a special router bit for metal. So with a bit of work you can make it happen.

That's strange. I have 2x the 3,5mm drill w. countersink and one 4,5mm drill w. countersink and none of the drill bits have any machine planed area on the shaft (unlike the normal centrotec metal drill bits). They are completely round, like any other drill bit. And any other drill bit will be perfectly centered. The counter-sink bit has a machined plan on the shaft however (not visible on your picture).

I have had my countersinks for a few years, perhaps the design has changed.

 

[tbellemare]

The package shows a depth of 8-20 mm. It looks to me like you could extend it to 40 mm reasonably.

I just took the bit out and it had a totally cylindrical shaft and the OAL was about 50 mm.

Tom

 

[AlexThePalex]

I have had my countersinks for a few years, perhaps the design has changed.

Guess so. Mine is brand new, got it for a month now.

 

[Daniel_n]

The package shows a depth of 8-20 mm. It looks to me like you could extend it to 40 mm reasonably.

I just took the bit out and it had a totally cylindrical shaft and the OAL was about 50 mm.

Tom

The problem with extending the original drill bit to far is that the chip removal might be suffering, as the spirals don't go all the way down to the countersink. However I have rarely have any problems with this. But a longert 3,5mm drill bit with spirals al the way is problably a better choice.

 

[tbellemare]

Good point, Daniel. I agree completely.

Tom