Review of Festool T15+3 and Centrotec bit holders
After getting the Festool bug last summer, I bought a T15+3 drill. The major advantages of this drill compared to the competition are the brushless electronically controlled motor, the electronic clutch, and the extra chucks.
The brushless motor has several advantages – it is more efficient than a brushed motor, and it doesn’t have brushes to wear out. Festool claims that this extra efficiency allows the 15 volt Festool T15 to exceed the performance of most 18 volt drills.
The electronic control system both protects the drill from overheating and over torquing, and also acts as the clutch mechanism – there’s no grinding mechanical clutch on this drill. At low torque settings the drill’s maximum speed is limited so you don’t overdrive the torque setting with the inertia of the drill and chuck.
The T15+3 kit includes several chucks – the usual Jacob’s-style 3 jaw chuck, the Centrotec bit holder chuck, the offset chuck, and the right angle chuck. I’m not going to invest a lot of time writing about the various chucks since they have been well covered in other reviews, but I wanted to examine the Centrotec chuck and bit holders.
The Centrotec system is a little different than other similar ¼” bit holders in that the Centrotec bit actually fits inside the drive shaft of the drill. The Centrotec chuck is nothing more than a plastic retaining system – the bit holder is driven by the drill shaft itself. The two advantages of this system are the reduced length of the drill, and low runout. Runout is bit wobble. This may not be a hugely important issue in a hand-held drill, but it is listed as a feature.
I have 3 Centrotec bitholders – the one that came with the drill kit (492539), the spring clip version (492648), and a second regular bit holder given to me today by Festool Dan who happened to be at a local tool show today. He gave me the bit holder because I complained that the bit holders I had didn’t seem to run any more true than any others I have used – particularly the spring clip one. I decided to test them. Here is the test setup: a Bridgeport mill with a dial indicator.
This particular dial indicator is a back plunger type.
I chucked it up and let it go. Actually, I attempted to chuck it up but found that the bit holder is actually .275” and didn’t fit in my collet without a little prying.
The spring clip holder that I observed had the most runout measured at .020”.
The regular holder included in my T15 kit measured about .008”
The bit holder from Festool Dan measured .012”
I also tested the drill shaft itself – it measured less than .0005” runout – very impressive.
The Jacobs style chuck measured .002”.
How much is too much? If my spring clip holder had any other name on it than Festool, .020” wouldn’t be unheard of. From Festool, especially since low runout is considered a design feature, I’m disappointed – the bit holder visibly wobbles much more than a $30 holder should. I can say that I am very impressed by the potential of the low runout design of the T15+3, but based on at least one of my examples, Festool isn’t immune to manufacturing tolerance issues. Kudos to Dan for giving me a spare bit holder no questions asked though.
This is a pretty minor issue in the grand scheme of a great tool. I really enjoy the power and ergonomics of this drill, and the electronic control system is really neat.
My rogue's gallery of Centrotec bit holders