How can I take a part my dewalt 12 volt drill

No it only fits the models it is designed to fit. Go on eBay to check this.

I will interpret this as "can I get replacement batteries for my 12V cordless shop source drill?" probably not. Most manufacturers phased out 12 volt tools years ago, replacing them with 18 or 20 volt tools , though a few people still sell dewalt 12 volt batteries.

http://powertoolshelp.com/dewalt-dc742ka-cordless-hammer-drill-users-manual

Knock the back end against something. Or shake the drill and if it sputters, it could be a loose wire, or more likely worn brushes. If that doesn't do anything, open the case and check with a volt meter if you are getting any current past the switch (ie hold the terminals from the volt meter onto the brushes or onto the leads coming out of the top of the switch.)

If you get a reading of 19V to a couple volts less, then you're switch is most likely okay. Check for worn brushes. Or a motor replacement might be necessary. (Yes it's easy to do)

generally 1 hour and there are indicator lights on the charger to notify you when charging is complete.

Brushes over time will wear down so comparing from the old to new will not look the same. If 18V brushes fit into the your drill then it should be fine.

as long as they are the same volts they should.

tirb

a higher voltage means more drilling power but it can also mean more weight - don't buy a drill you won't need, 12 volt drills are powerful enough for most home users, bigger models just weigh more so think carefully about what you will be using the drill for.

this 2 chuck are 3/8 jaw opening,double sleeve u can hold the chuck will opening it at the sametime.the sinlge sleeve u have to runs the drill while running slow rev/for to remove the bit etc.
i prefer metal sleeve.