N.m or Ft. Pounds equivalent torque setting on drills

[skipclemmons]

For the different Festool drills, is there a torque setting which corresponds to a torque wrench?  If I set the dial on my T15 or CXS at a particular point, what is the torque I can expect?  Is this in the manual somewhere?  This will help me explore the socket driver attachment of the Centrotec Set.  Thanks.

 

[Captainwrinkles]

I've often wondered this myself.

If you have a torque wrench, you could attaching your drill to the front and test it out. It should give a fairly accurate result.

Benn

 

[stairman]

no need to wonder,  use this
http://www.unitconversion.org/energy/newton-meters-to-foot-pounds-conversion.html

 

[ach_78]

Hi all,

New to FOG!!  [tongue]

I'm in the market for a new drill and those questions about torque are quite interesting and IMO overlooked. The electronic clutch is one of the highlights of the Festool line of drills and a really neat feature. I strongly believe that it has more potential than it is regarded by most.

I've been using a BOSCH drill (and not even a blue one at that) with a mechanical clutch before and did some tests with a Facom torque wrench that I have (the one that has a screwdriver shape, range 0.5-2.5N.m). I could easily stick some labels on the clutch setting ring, pinning down the exact position of the selector for landmark values in N.m (I did from 0.5N.m to 2.5N.m in steps of 0.5 on mine).
First it has proven to be a reasonably repeatable addition as long as I drove the screw slowly at the end.
Second, it has taught me that the ring was not linear.
Third, I started developing a kind of "sense" of what was the proper torque for each screw size/wood hardness combination. I think it isn't a bad habit. Knowing this, for a given job I could just dial in the value I knew was just right (for example to flush the screw heads in pine without driving through) with little to no trial and error adjustments.

When browsing the T18 specs (as an example since it's the drill I'm am eyeballing  [embarassed])  I see in the french website states that the torque range of the electronic clutch are : position 1 => 0,5 - 8N.m / Position 2  => 0,5-6 Nm

First it is interesting to see that the lowest setting (0.5N.m) is identical regardless of the drive speed. IF that is right, it tells us that the system knows in which gear you are in, and adjust it's clutch torque at the motor level to achieve the same desired output shaft torque. It is smarter than I thought.

--> Can anyone confirm that the actual output torque seems to be identical in speed 1 and 2 when selecting the lowest torque setting ? (try driving a small screw in soft wood, and see how flush the head goes in both positions. Go slow, approx same rpm in both speeds to rule out any inertia factor out of the experiment)

Second, the higher value is not identical : 8 vs. 6 N.m. I wonder if in gear 2, the torque limiter is bottoming out from a certain selector number (say, from 22 to 25, in speed 2, the torque limiter follows a flat curve) or if the range is fully redistributed on all the selector numbers. Again the driver could be "smarter" than I think, remapping the torque curve differently in speed 2.  Actually that would be a bad news for me as I would prefer that the torque setting was identical in both speeds (i.e one dial number = 1 torque value in N.m) at least up to a certain number that I would know where a flat curve is reached in speed 2.

--> Again it would be interesting to try and see if you are actually getting more torque in speed 2, all the way up to dial number 25 or if it reaches a maximum before that and then just does nothing more.

Idealy, if some one could test his dial settings in both speeds, going slowly against a torque checker like this (though this one has a slightly too hight of a measurement range) we would have all the answers right away. I wish I had access to one, unfortunately I don't
http://catalogue.facom.com/fr/categorie/serrage-controle/controleurs-de-couple/produit/e-2000-controleurs-de-couple/e-2000-50

I got one more question : at a given torque dial setting, does it seem to make a difference if you drive the screws slowly or at full speed until the clutch kicks in ? Again, easy to try, and I am very curious about how good the controller is at sitting screws repeatably no matter at what speed you're going (quite difficult to achieve as at higher speed some inertial is involved).

Now it's been said a driver/drill isn't a torque wrench. That is right, BUT, in many cases it could serve a great purpose nonetheless.

For example, that table here :
http://www.dynamometrie.facom.com/fr/support_telechargement/guide_serrage_boulonnerie.pdf
Tells you for each type of metal screw and bolt, what is the proper torque to use. Anytime you are working on metal assembly (metal working, cars, bicycle, you name it), working on relatively small screws (say M3-4-5-6) the proper torque is very well within the capability of Festool drills. Why not work on your big $ bicycle with your Festool drill ? If we had a good sense of the N.m value it would be a ton safer than using L shape wrenches manually.

Sometimes I just want to bold down things knowing that I am in the ballpark of the proper value... firmly setting the assembly without stripping anything and yet, I don't want nor need a torque wrench precise down to several % for that job.
Getting in the ballpark is A LOT better than nothing.

The Festool e-clutch being electronic, the range being specified, it is totally possible that the torque selector is actually quite consistent even between different drills. Although Festool doesn't advertise nothing about that, just saying. It's technically possible.

Anyone willing to make some quick tests and share the results, you are welcome.

Cheers!

 

[AlexThePalex]

Why not work on your big $ bicycle with your Festool drill ? If we had a good sense of the N.m value it would be a ton safer than using L shape wrenches manually.

Hi, welcome to the FOG.

I love my Festool drills, especially the T15, but I find the electronic clutch very inconsistent and therefor very unreliable. I prefer to not use it, ever. If I need to use a clutch, I get out the older C12 NiCd with mechanical clutch, that's something I can work with.

I have a very nice bicycle and ride over 1200 km per month on it, so I also have to do a lot of maintenance. I really don't like to use any of my drills on it, no matter how precise they are. I always use hand tools. The extra speed delivered by a power tool is simply not required, and the risk of stripping screws or slipping and damaging something is way too big. I never use a power tool working on any kind of equipment, in my eyes they're better used for constructions purposes. When it comes to delicacy, the hand wins.

 

[ach_78]

Hi,

That is the first time I read a complain on the electronic clutch, very interesting though, could you explain what you mean by inconsistent ?

Is the clutch too slow to react ? Or does it disengage properly just not applying the same torque each time ?

 

[AlexThePalex]

Well, by inconsistent I mean that with the same clutch setting the screws don't always stop at the same depth, but can vary a couple of millimeters. Even if you take care to drive them with the same speed. When you use different speeds the difference is even bigger.

So I more or less stopped using the electronic clutch with my T15 completely. Good thing is though, that the control of the trigger is sublime, so I learned to ease the screws in by using the trigger instead of the clutch. It does work slower though, and I wouldn't recommend this technique in a production environement.

 

[ach_78]

Ok got it.

Have you ever had a better result (inconsistent depth of flush screws) with a different drill ?

Because of the very nature of wood, it isn't a reliable way to set screw depth by torque. That is why they have a depth stop chuck.

Still if the drill e-stop itself is unreliable, that would be a deal breaker (for me at least)