Launch Slideshow

Brushless Impact Driver Teardown

Brushless Impact Driver Teardown

  • http://www.toolsofthetrade.net/Images/1444184785_DW_teardown_1_tcm80-1820462.JPG

    600

    DeWalt DCF895 Brushless Impact Driver – shown here with compact battery. Let the teardown begin.

  • http://www.toolsofthetrade.net/Images/1317774357_DW_teardown_2_tcm80-1820472.JPG

    600

    Remove Torx screws that hold clamshell housing halves together.

  • http://www.toolsofthetrade.net/Images/128258505_DW_teardown_3_tcm80-1820454.JPG

    600

    Remove Phillips head screws that hold gear housing in place.

  • http://www.toolsofthetrade.net/Images/1228885525_DW_teardown_4_tcm80-1820493.JPG

    600

    Peel rubber cover off end of gear housing.

  • http://www.toolsofthetrade.net/Images/144675415_DW_teardown_5_tcm80-1820456.jpg

    600

    After removing two Phillips head screws lift off the hex chuck access cover.

  • http://www.toolsofthetrade.net/Images/2053351959_DW_teardown_6_tcm80-1820457.jpg

    557

    Pull out spring-loaded accessory release button (you load bits by pushing them into the chuck; to get them out you must push this button).

  • http://www.toolsofthetrade.net/Images/1238379615_DW_teardown_7_tcm80-1820458.jpg

    599

    Lift off ring that contains the three LED lights.

  • http://www.toolsofthetrade.net/Images/236135517_DW_teardown_8_tcm80-1820460.JPG

    591

    After peeling off the adhesive stickers that span the joint pull the housing apart and remove the mechanical parts.

  • http://www.toolsofthetrade.net/Images/1261887458_DW_teardown_9_tcm80-1820465.JPG

    589

    This is the speed selector switch (the tool has three speeds).

  • http://www.toolsofthetrade.net/Images/364949102_DW_teardown_10_tcm80-1820539.JPG

    600

    Unclip wiring harness from electronic controller.

  • http://www.toolsofthetrade.net/Images/1742072934_DW_teardown_11_tcm80-1820475.JPG

    599

    Remove Phillips head screws from back of controller.

  • http://www.toolsofthetrade.net/Images/538375216_DW_teardown_12_tcm80-1820479.JPG

    599

    Pull controller off the bearing on the back of the rotor (the rotor is the part of the motor that spins).

  • http://www.toolsofthetrade.net/Images/419055721_DW_teardown_13_tcm80-1820561.JPG

    600

    Pull stator off of rotor (it’s tough because a powerful magnet in the rotor is holding it on).

  • http://www.toolsofthetrade.net/Images/180248618_DW_teardown_14_tcm80-1820488.jpg

    572

    Here are the main components of the brushless motor. Brushless motors are more durable (no brushes or commutator to wear out) and more efficient (so they boost the runtime of cordless tools) than conventional brushed motors.

I tear things apart so you don't have to. Well, not really – I tear things apart because I am curious about what's inside, especially when the manufacturer makes a big deal out of it. Lately, the big deal has been brushless motors so I disassembled DeWalt's new brushless impact driver and shot these photos.

I didn't mess with the gears or battery because they're no different than what you would find in a tool with a brushed motor. And I didn't ask DeWalt how to take the tool apart so don't take my instructions as gospel. The impact driver worked fine after I put it back together – but taking it apart probably voided the warranty.