Drill Bits Falling Out of Chuck...

[Deansocial]

It happens to me almost every time I use my Festool drills.

I guess I am just to stupid to know how to tighten a bit in a keyless chuck.

Maybe you could make a video to show us the proper way to do it.

It happens to me too, and you are correct--it is from being stupid.  [big grin] It is not the chuck, it is the operator not inspecting the bit they just installed. Contrary to intuition, it is actually caused from the chuck gripping too well.

This happens with non-round shanks, like hex and tri-flat bits, and the operator closes the jaws by running the drill and holding the bit. The jaws have enough immediate grip that they will catch the lobes or points on the shank and begin tightening against them. A chuck with less immediate grip will allow the bit to slip a fraction of a turn to align the flats with the jaws.

If you have caught the lobes or points on the leading, or uphill side, the bit will stay locked in place while under load (e.g. while drilling), but as soon as the load is removed, the bit will relax in the jaws and re-seat the way it should have been set. This is what makes people think that the chuck suddenly let go of the bit--because it held it long enough to begin heavy drilling.

To stop this from happening, simply get yourself into the habit of looking at the flats of the bit as you begin to tighten the chuck.

The image below shows the jaws gripping a hex shank bit, but gripping it on the points.

yep because that explains why jmbs video shows the round bit falling out. the same as mine. i find bigger the bit worse it gets and if i use a hole saw i have to endage my fingers holding the hole saw when stopping the drill to prevent damage to the floor and stop it destroying the drills break aswell for that matter. Utter crap chuck

 

[tbellemare]

'Sorry to have left this thread after I started it. I was working on my Fall Project...

The only time I have ever seen a round bit fall out of a Festool chuck was because the operator just ran the chuck closed using the motor and thought it should hold. You have to grab the chuck and turn it clockwise until it can't turn any more. It stops the shaft from turning by itself and the tightening ring of the chuck will continue turning a little. It isn't tight on the bit until you make that last 1/8 turn or so and it comes to a solid stop. Other keyless chucks that I've used required two hands on the chuck because the drill shaft didn't stop turning on its own so you have to hold the back of the chuck while tightening.

As I stated in beginning, hex shanks require more attention and Rick detailed that.

Tom

 

[Deansocial]

i dont use the motor to tighted my chuck i use my hand and turn it tight and it still comes loose, my NON racheting dewalt chuck does not do this and my racheting bosch does not do this so why does it happen on a drill 2 1/2 time the price

 

[Rick Christopherson]

yep because that explains why jmbs video shows the round bit falling out. the same as mine. i find bigger the bit worse it gets and if i use a hole saw i have to endage my fingers holding the hole saw when stopping the drill to prevent damage to the floor and stop it destroying the drills break aswell for that matter. Utter crap chuck

Is it some sort of cultural thing? The rudeness I see from many of the UK posters makes me not want to participate on this forum.

As for the two videos above, the first one shows hex-shank bits. The second one shows him installing the bit slightly skewed (it is obvious enough that you can see it in the video). Re-watch the video and see how much extra time and care he takes to make sure the bit is centered and straight in the second jaws before tightening. It is the same effect I mentioned previously--the chuck grips so well that it will still hold a bit that is not properly seated. If you properly seat the bits, they won't loosen.

 

[Deansocial]

Must be a cultural thing, I express my opinion on things, deal with it

 

[Rick Christopherson]

Now, what is your explanation for round bits falling out of the chuck? Because those are the only bits that fall out of my chucks.

Sorry Chris, I didn't see your posting before. However, I believe I may have answered your question anyway. Another aspect to this may have something to do with the geometry of the jaws. I haven't examined the mechanisms in the various chucks, but I think the Festool chucks grip the bit a little more at the deeper portion of the jaws. While this will hold a bit much firmer, it can also permit it to hold a bit that is slightly skewed.

 

[Deansocial]

JMB, if it no hassle could you remake a video taking the greatest care to make sure the drill bit is it straight to give an apple for apples comparison.

 

[jmbfestool]

yep because that explains why jmbs video shows the round bit falling out. the same as mine. i find bigger the bit worse it gets and if i use a hole saw i have to endage my fingers holding the hole saw when stopping the drill to prevent damage to the floor and stop it destroying the drills break aswell for that matter. Utter crap chuck

Is it some sort of cultural thing? The rudeness I see from many of the UK posters makes me not want to participate on this forum.

As for the two videos above, the first one shows hex-shank bits. The second one shows him installing the bit slightly skewed (it is obvious enough that you can see it in the video). Re-watch the video and see how much extra time and care he takes to make sure the bit is centered and straight in the second jaws before tightening. It is the same effect I mentioned previously--the chuck grips so well that it will still hold a bit that is not properly seated. If you properly seat the bits, they won't loosen.

Rude umm okay whateer. Im glad you dont participate with stupid comment like that.  You clearly dont know what your talking about!  On the second drill I dont try and seat it properly I try and show more clearly that it dont tighten the bit any more than the first drill by rotating it i am showing it isnt tight yet thats all  how can you put a bit on the skew?!?! it would wobble every where if it was not straight.

 

[Mirko]

yep because that explains why jmbs video shows the round bit falling out. the same as mine. i find bigger the bit worse it gets and if i use a hole saw i have to endage my fingers holding the hole saw when stopping the drill to prevent damage to the floor and stop it destroying the drills break aswell for that matter. Utter crap chuck

Is it some sort of cultural thing? The rudeness I see from many of the UK posters makes me not want to participate on this forum.

As for the two videos above, the first one shows hex-shank bits. The second one shows him installing the bit slightly skewed (it is obvious enough that you can see it in the video). Re-watch the video and see how much extra time and care he takes to make sure the bit is centered and straight in the second jaws before tightening. It is the same effect I mentioned previously--the chuck grips so well that it will still hold a bit that is not properly seated. If you properly seat the bits, they won't loosen.

Rick, this comment is uncalled for...

Mirko

 

[mouppe]

Can we just delete/modify the Anglo-bashing comment and move on? This was a really interesting discussion until the totally out-of-order cultural thing comment.

I thought Anglo-US conflicts were limited to the Ryder Cup this weekend!

 

[Deansocial]

Can we just delete/modify the Anglo-bashing comment and move on? This was a really interesting discussion until the totally out-of-order cultural thing comment.

I thought Anglo-US conflicts were limited to the Ryder Cup this weekend!

+1

 

[jmbfestool]

Just loading a second video!

JMB

 

[spikfot]

I've the non ratcheting chuck on my t15 and never had a problem w/ it.  I use it mainly w/ the Centrotec kits, but ran some 10mm shank forsners half the day yesterday with out a slip

 

[jmbfestool]

I've the non ratcheting chuck on my t15 and never had a problem w/ it.  I use it mainly w/ the Centrotec kits, but ran some 10mm shank forsners half the day yesterday with out a slip

Yeah the drill will hold but you have to tighten a lot more than you should be doing with a NEW drill and a drill of that price! Like I said before I have tighten really tight before and it has come loose when I was drilling out 8 door locks! but I dont like to tighten hard and then you have to undo it which is more difficult festool should of just made it a ratchet in the first place and not made a second ratchet chuck which I will have to buy costing more money. Thats why just like Dean I avoid using the chuck if I can simple if I didnt ill properly throw it through the window it.

JMB

 

[jmbfestool]

Here is the second Video!  Even though the first Video was completely fine!    I like festool and own a lot of it and I wouldn't want to ly and make an unfair test on the festool drill its just the truth the festool chuck stinks!.    The first video both drills the bit whas in all the way and STRAIGHT and I tried my best to tigthen them with the same pressure   The second video is just the same AGAIN!  Just a more advantage to the Festool as I give the Milwueakee more hammer I bang it and wiggle it alot more

Oh its a bit of WET MDF I found out side just!  Yes its raining again in the UK!
P1010642

JMB

 

[Deansocial]

Thanks for making that clear jmb. Have you found it hard to drill meta with it as it just wont grip the bit? i do

 

[jmbfestool]

Thanks for making that clear jmb. Have you found it hard to drill meta with it as it just wont grip the bit? i do

Yes!  Often the bit would spin in the chuck when drilling metal you really have to tighten it as hard as you possibly can! really tight! to avoid spinning in the chuck.

 

[Deansocial]

shhh dont tell anyone but ive even used a pair of grips on mine to tighten it

 

[jmbfestool]

shhh dont tell anyone but ive even used a pair of grips on mine to tighten it

lol

 

[Holzhacker]

I've owned or used pretty much every cordless and corded drill out there over the last 40 years. The bit falls out of almost every drill at some time or another. Yes, bits have fallen out of my T15. However, I can't say that bits fall out of the T15 or C12 any more frequently than any other brand drill. Being in a rush and not tightening properly, sudden reverse spin and high torqueing seem to be the root causes of the chuck loosening enough for the bit to fall out. I can't agree that this is a bigger problem with Festool chucks.