Torquing down a Bit in the T+3 Drills

[ForumMFG]

Ever since I have been using the T+3 drills I have been having this issue that is bugging the crap out of me.  When you insert a new bit, start to tighten it and then when you torque it, it sounds like gears  or something is grinding for a second or 2.  It makes me feel like I am doing something wrong or maybe this is not the way I should be tightening the bits?  Has anyone else experienced this?  Is this normal or not?

-Dave

 

[Tom Hummel]

Ever since I have been using the T+3 drills I have been having this issue that is bugging the crap out of me.  When you insert a new bit, start to tighten it and then when you torque it, it sounds like gears  or something is grinding for a second or 2.  It makes me feel like I am doing something wrong or maybe this is not the way I should be tightening the bits?  Has anyone else experienced this?  Is this normal or not?

-Dave

Dave,
That sounds like the normal racheting action of the newer chucks

Tom

 

[Brice Burrell]

Dave, do you mean the keyless chuck? Tom posted about the ratcheting action of the some chucks, the Festool keyless chucks don't have the ratcheting feature.

Are you getting this sound when you really give the chuck a good hard twist? I noticed the my T15 will make a bit of groan if I really give it some torque, I think what is happening is the torque is slightly turning the motor and that is the sound you're hearing. That is a guess on my part, maybe Rick can chime in on this one.

 

[ForumMFG]

Brice,

Yes, that is what I am talking about.  I am getting the same sound and aI kind of figured it hard something to do with the motor.  Since it has something to do with the motor I thought it might be bad for the drill?

-Dave

 

[Brice Burrell]

I don't know if it's bad or not, however, I only got this sound when I was trying to figure out what the heck you were doing to get a grinding sound. I had tr really torque the chuck to get it groan, in my opinion that was more torque than you'd need for the chuck. I'd consider that much torque excessive and I wouldn't be comfortable doing that to my drills on a regular basis. 

 

[JJ Wavra]

I don't know if it's bad or not, however, I only got this sound when I was trying to figure out what the heck you were doing to get a grinding sound. I had tr really torque the chuck to get it groan, in my opinion that was more torque than you'd need for the chuck. I'd consider that much torque excessive and I wouldn't be comfortable doing that to my drills on a regular basis. 

Brice,

I have the same grinding sound and if I don't torque on the drill I have had quite a few bits fall out.  Usually I just spin the chuck in my hand and it is tight enough but that has not worked for me with either a drill bit (round) or hex like on a driving bit. 

JJ

 

[tbellemare]

I'm not sure if I understand what you guys are talking about but with my C12 and T +3's, I have the same results using the keyless, Jacobs style chuck.

I get a whirring sound and then the transmission seems to grab and I can crank the chuck tight. I've never had it come loose and I've done a lot of drilling and driving with it.

Tom

 

[ForumMFG]

I'm with JJ.  I don't don't apply that much force.  Just enough to make it tihgt and not have the bit fall out.  If I don't use that much force, I don't get that sound but the bit falls out.

 

[Brice Burrell]

With the drill I tried it took excessive force to get the transmission to groan. I've had bits fall out too, great drill but poor keyless chuck.

 

[bobbobbob]

Are you putting the direction switch in the middle (or 'interlock') position when tightening the jacobs chuck?  I know that's how to do it on a C12, but not sure on the T+3.

 

[ForumMFG]

I've tried to put it in the middle but as soon as the chuck turns to the left or right, the switch moves on you.

 

[bobbobbob]

You may want to check your manual to see if the new T+3 drills even has the 'interlock' position on the reversing switch.  I tried the Festool site but didn't find the manuals for the new drills.

 

[Forrest Anderson]

You may want to check your manual to see if the new T+3 drills even has the 'interlock' position on the reversing switch.  I tried the Festool site but didn't find the manuals for the new drills.

If you check out Part 1 of the Consolidated List of Festool Links here on FOG, and look under "Drilling", you'll find a link to the manual.

As far as I can see, it makes no mention of needing to put the right/left switch into the in-between position in order to tighten the chuck.

Forrest

 

[ForumMFG]

Can someone confirm this?

 

[tbellemare]

Hi Dave:

I have never done anything with the C12 or T +3 drills other than turn the chuck collar clockwise. The drill motor grabs.

Tom

 

[Rick Christopherson]

No, the forward/reverse switch is entirely electronic with a neodymium magnet that the control board senses to tell it which direction to turn. There is no interlock and the switch does not connect to anything.

I never understood the original question so I did not respond previously. If the drill is rotating while tightening the chuck, then the shaft lock pins are not engaging. These are the 3 green pins in the image below. When the motor is driving the output shaft, these pins are held in the center of a detent area and allow movement. However, when the output shaft is turning the transmission, these pins move out of the detent area and jam between the pink colored lobes and the gear housing.

There are two situations where these pins will not function as well as they should. The first one is having too much grease in the gearbox. I learned this because I mistakenly added grease to my gearbox when I reassembled it. On my older C-12 this added grease causes the chuck to make a full revolution before the pins engage.

The second cause would be from over torquing the output shaft and damaging the pink colored lobes shown below, or the transmission housing. I have heard of some people that wanted to compare the power of two different drills by chucking them both together to have a "tug of war". If you do this with a Festool drill, you will likely destroy the Festool transmission and possibly burn out the other drill.

Once these pins engage, you cannot turn the output shaft. If you turn the output shaft hard enough to overcome this mechanism, you probably have damaged your drill (sorry Brice).

 

[JJ Wavra]

Rick,

I wonder if I can make an inquiry into what you just said.  Is there a time when the green pins would not me engaged after using the drill?  I ask because what sometimes happens to me is that when I go to tighten the jacobs chuck, I can do it without any change in position of the chuck in relation to the body of the drill.  Other times and I think that this was what the initial post was about you go to tighten the chuck and you will maybe get a 90 degree rotation before it stops and you can tighten the chuck appropriately. 

JJ

 

[greg mann]

Sounds to me like you are hearing the pins engage as you rotate the chuck, at which point it will resist furter rotation because of the pins being engaged. Unless, as Rick has pointed out, you use excessive force and damage the pins or their surroundings. This should be unnecessary and it should not be difficult to tighten the chuck enough. Interestingly, the gold coating, or Tin coating, put on drills these days make gripping with a chuck much harder if the coating is on the shank. It has a lower coefficient of friction than an uncoated tool. That is why you usually don't see the coating on the shank. Just another piece of trivia.

 

[Brice Burrell]

Rick and Greg, the sound I heard was a small groan, what sounded like the motor turning ever so slightly. Maybe it is the sound of the pins. My drill is working fine so I don't believe there is any damage. I don't plan on torquing my chuck like that nor do I see a reason to.

 

[Rick Christopherson]

......Other times and I think that this was what the initial post was about you go to tighten the chuck and you will maybe get a 90 degree rotation before it stops and you can tighten the chuck appropriately.  

Yes, this is similar to how my C-12 drill operates because the thick grease that I added makes the pins a little sticky and it takes a slight rotation for them to move into position. The other C-12 drill that I did not take apart does not do this.

I haven't noticed this on the T-12 or T-15 yet, but I don't use these as frequently.

Brice, yes it appears you are spinning the gearbox slightly (as do I). It is not that big of a deal so long as you cannot rotate the motor too much. I fried the electronics on a C-12 that I took apart by spinning the motor by hand fast enough to send power backward from the motor (generator) into the electronics module.