Thread: Pistol drill - chuck removal etc

How do chucks on pistol drills normally attach? I've got the LH screw out, but does the chuck screw on or is it just on a taper? If it screws on, what do I grip to turn against? This is a DeWalt 240v. Picked it up at the dump. Cleaned the plaster dust out, works great, but needs an output bearing. It has a sturdy 40:1 gearbox that I was eyeing off for my power feed but it might be too good to sacrifice. It's got a ton of grunt.

G'Day,
I usually put the short end of a large allen key in the chuck and tighten, a sharp whack with a hammer does the deed.
Regards,
Martin

Afternoon Bryan, haven't had dealings with a DeWalt, but B&D and Bosch, just place the chuck key into the appropriate hole in the chuck, and whack it with a resilient hammer anti-clockwise (as you face the output end of the chuck). Essentially the other two models had a double ended threaded spigot. HOWEVER the attached manual p4 implies a hex bolt - this may be useful info.
Current new purchase $318- $365 - well done. Seems like its sold as a 'mixer' drill as well as rotary. Mark

Before whacking anything with a hammer, open up the chuck jaws,get a light and peer down inside. Sometimes there is an axial retaining screw that holds the chuck to the shaft.

If you go here and look at Dewalt power drills you can scan through the various parts diagrams to see the various ways that they hold the chuck to the shaft. The model number of your drill is not there but i am sure you will find something similar.

DeWALT Electric Drill Parts - Tool Parts Direct

So it's a RH thread, great I'll give that a try. Thanks for the manual too. I'd say this one had been used for mixing. Seems to be single speed, as in on or off, which is odd when the spec says 0-550 rpm. Maybe it's a fault and that's why it was binned. Makes it unsuitable for a power feed as is. Certainly seems heavily built though. Probably weighs twice my Hitachi. Ok, significantly more.

Edit: Yes I found the axial screw, thanks Avery. And I even remembered from somewhere it would be a LH thread. The manual Mark posted shows the hammer method of unscrewing. But thanks for that link also.

Chuck removal (fig. B)
• Open the chuck jaws as far as possible.
• Insert an Allen key (10) into the chuck and remove the chuck retaining screw (9) by turning clockwise.
• Tighten an Allen key into the chuck and strike it with a hammer as shown.

Originally Posted by Bryan

Seems to be single speed, as in on or off, which is odd when the spec says 0-550 rpm. Maybe it's a fault and that's why it was binned. Probably weighs twice my Hitachi. Ok, significantly more.

I note the weight is 3.4 kg!! Also that it is touted for tapping (once you get the variable speed operating, eh)!! The manual p20 points out that "To run the tool, press the variable speed switch (1). The pressure exerted on the variable speed switch determines the tool speed. If necessary, press the lock-on button (2) for continuous operation and release the switch. The lock-on button works only in full speed, forward rotation." Presume you'll want to confirm the operation of that pressure switch.
Cheers, Mark

Mark, yes I noticed that too. Definitely an issue with the trigger. That looks like the sort of thing that never goes back together.

It's certainly a beefcake. It's rated at nearly a horsepower, and geared down 40:1.
Wait a minute, to produce 550 rpm the motor would have to do 22000! Can that be right? But I counted 40 turns. Maybe I should count again.

Edit: Sorry, that's power draw, output is 560W - closer to 3/4 hp.

They reckon that the output is 560W (as opposed to input 710W). This rates the tool at 3/4 hp. Norwest Tool Centre - Professional Quality Tools :: DeWalt D21520-XE Spade Handle Drill 13mm
A fine piece. By the way spares for dewalt gear = http://www.woodworkforums.com/f13/wh...t-parts-80651/ Mark

Not sure if this is useful, but this diag of older (but maybe similar) model provides parts diag. By the way one of the earlier websites provides vid of removal of chuck as we were discussing earlier - too easy. Mark

Thanks Mark. Yes that's very similar. I will get a price on a new trigger unit. I noticed my error on the power rating and edited my post. Got the chuck off. The bad bearing says 'CHINA'.

Originally Posted by Bryan

The bad bearing says 'CHINA'.

The company name of a top quality bearing manufacturer in Germany no doubt?