Random torque on PDC 18/4 Li

[sdes]

I've had some Hitachi cordless kit for ages but finally gave in to the temptation of Festool UK's free extra battery pack and treated myself to a PDC18/4.

Beautifully built, but what is going on with the torque control?  I've not had an electronic clutch drill previously, but putting up some plasterboard was thinking this would be very useful. The screws seemed to stop at very variable depts, so I asumed there might be variation in the timber battons behind etc, so decided to give it a better chance.

I used a piece of 18mm MDF - cant get much more consistent material and drove a series of identical plasterpard screws into it. Very variable depths (I do understand from the instructions that the torque does vary according to which gear the tool is in, but I kept it in the same gear).

It also seems to vary considerably according to whether you put the screw in quickly or slowly, or pull the trigger quickly or slowly - to a point where you might as well put it in screwdriver mode and judge manually.

To test the theory further, I tried using the drill on a simple torque driver I have for bicycles - basically it just twists a long hex drive bar and you can see the the deflection as Nm on a simple needle pointer, I seemed to get about a variation of about 300% on the same torque setting, i.e. squeeze the trigger very gently and it might register say 1Nm, squeeze fast ant it gets to 3Nm.

My 8-year-old quite knackered mechanical clutch Hitachi seems much more consistent. Anyone else encountered this? 

Thanks

 

[AlexThePalex]

I have the exact same experience with my T15. Torque is soo inconsistent I can't use it. I learned to drive the screws judging the depth by eye.

Some time ago I sold a C12 drill to somebody who paid good money for it despite it being the older type. He wanted this one specifically because it had a mechanical torque control and thought the new electronic ones were crap.

So yeah, you're not the only one who thinks this.

 

[Bob D.]

I have a T15 and also a Bosch PS10BN that both have an Electronic Clutch. The T15 I haven't used the EC enough to say I have this problem but the Bosch I have had for a number of years and while a much lighter duty tool meant for driving screws in tight spaces I see the same issue when using it. The Electronic Clutch does not seem as consistent as mechanical clutches.

 

[sdes]

Interesting - especially someone paying good the older version of the Festool with mechanical clutch because it is more reliable / accurate than the electronic one.

I suppose the lesson is electronic isn't always better, it sounded more advanced and accurate though, seems its brain doesn't react quickly enough to whatever sensor is triggering / arresting it, so better with something that just manually slips intantaineoiusly as soon as the torque limit is reached.

Given it seems to be inaccurate, is there any way to turn that beeping off and I will resort to using delicate finger control like with a basic drill driver with no clutch at all.

Does anyone know if Festool make a mechanical torque attachment that would fit this drill?  Rather defeats the object, but at least I'd have better control.

 

[Bob D.]

I wouldn't be so quick to dismiss the EC based on just 2 or 3 reports.

Mine (the T15 and the Bosch PS10) seem to be finicky/inaccurate too, but I have no means of testing and proving that other than doing a simple test as you did. Yes, MDF seems the perfect medium to test with given it's more consistent than you average piece of timber. But are a couple random tests enough to claim it's inferior to the old style mechanical clutches I don't know. No doubt Festool, Bosch, and anyone else putting a EC on their tools has done loads of research and refinement of the concept before going into production.

 

[Bohdan]

but I have no means of testing and proving that other than doing a simple test as you did. Yes, MDF seems the perfect medium to test with given it's more consistent than you average piece of timber.

If it needs a special setup just to put screws in consistently then in real life IT DON'T WORK

 

[AlexThePalex]

Given it seems to be inaccurate, is there any way to turn that beeping off and I will resort to using delicate finger control like with a basic drill driver with no clutch at all.

Yes, just put the switch on top in drill mode. Unfortunately trigger control of the PDC is not as precise as on the T15, but it should work.

I wouldn't be so quick to dismiss the EC based on just 2 or 3 reports.

Mine (the T15 and the Bosch PS10) seem to be finicky/inaccurate too, but I have no means of testing and proving that other than doing a simple test as you did. Yes, MDF seems the perfect medium to test with given it's more consistent than you average piece of timber. But are a couple random tests enough to claim it's inferior to the old style mechanical clutches I don't know.

We're all talking from our own experience here. I myself don't need a scientific report stating everything is A-OK because next-gen is always better, when my screws don't line up in practice.

No doubt Festool, Bosch, and anyone else putting a EC on their tools has done loads of research and refinement of the concept before going into production.

Sure, they're perfect. I myself, again speaking from personal experience and my own perspective, don't like how Festool puts their tools filled to the brim with electronics. For instance, the speed control on saws like the TS55 and CS70 drive me mad with their constant whining and howling. People always ask me if the saw isn't broken, is it supposed to do that? Yes, I have to explain them, it's just the motor winding up and down to keep the saw at a constant RPM when it contacts the wood. Do I see a better cut than with other saws? Nope.

And then these drills, which are very nice to use, but I could do with a whole lot less beeping. I don't like tools with a constant attitude .

 

[Frank-Jan]

Does anyone know if Festool make a mechanical torque attachment that would fit this drill?  Rather defeats the object, but at least I'd have better control.

They have a depth stop chuck (it's a different one for the pdc/drc as for the C/T drills): link

(Price does seem to have gone up since I got mine, it was around 70€ when they introduced the thing iirc)

Personally I don't care much about the torque control, I just use it as a sort of failsafe for not breaking heads off when installing hinges in hardwood.

I remember when everybody was very happy with the little bosch driver when it got introduced years ago, so when I got one as an extra with a big demolition hammer I got to test it... I hated the thing, the torque setting was very precise... but you actually HAD to use it because it wouldn't stop turning when you let go of the trigger.