Printed Circuit Board 2610019984

First a disclaimer. I am an electrical engineer and I do a lot of hardware development, so I consider this actually to be a easy repair, but, this will be a bit challenging for those with no experience disassembling/reassembling electro-mechanical devices. The important thing is to keep the parts grouped as you go and pay attention. By far the hard part is reassembling the motor as it requires care and patience. Take photo's from various angles as you go along so you can see what it looked like when you are reassembling it. If you feel like you are getting tense or frustrated, stop, take a break. It really does help.

Please read the whole process once (or more) decide if you are up for it before attempting. Get a friend to help - an extra set of eyes and hands is very helpful.

1.) UNPLUG THE TOOL. Do it NOW if you want to live.

2.) Removing the set of brushes. These are two graphite block/spring assemblies that are under two plastic caps on opposite sides of the motor.

3.) Remove the Torx T15 screws that hold the case together.

4.) Unscrew the top cap of the tool (near the collet).

5.) Remove the hanger clip (near the ac wire exiting tool). Set all the external parts in a separate bin. Keep the internal parts in a different bin. This allows you to later know that everything that belonged inside got put back (nothing left over).

6.) Carefully separate the two halves of the shell.

7.) TAKE PICTURES before going forward.

8.) Be aware that the motor assembly is now just sitting in the case - and as we go forward, it will be easily popped out so be careful to not invert things.

8.) Remove the center plastic cover piece that holds the speed control adjustment knob.

9.) Remove the two screws from the strain-relief block that clamps the AC cord. NOTE: these are also T15 screws, but they are longer. Be sure not to confuse these with the other, smaller, case screws.

10.) Loosen the flat head screws to release the AC cord wires form the PCB.

11.) Pull the PCB (printed circuit board) and knob assembly up and away - but just enough to free it. At this point you should take a marker and make some kind of mark on the motor shell
so that you can reassemble it that same way. TAKE ANOTHER PHOTO of your markings and take note of the color of the wires and the holes they are in - you will need to match this exactly when you install the new PCB.

12.) This step is where you might get a little challenged. Here you will remove the motor parts from the shell that holds them in proper alignment. The objective is to access the field coil assembly (where the wires connect). There are three wires that need to be released from their push-in self-locking clamps - much like some ac outlets. Also, it may not be obvious, but the rear most section (plastic section) of the field winding pulls off of the metal part. This is where marking it with a sharpie will ensure it is replaced correctly. SO, carefully remove the motor sections from the housing so that you can remove the part where the wires connect.

13.) To release the old wires, look for locking tabs to release the plastic cover form the case. Take care not to force anything. Once the cap is off the wires will release and the old PCB will be free. Again make sure you know what color wires go in the holes. Discard the old PCB assy.

14.) Replace the plastic cap and press the wires into the correct holes - keep in mind that you want the wires to feed nicely (straight shot - not twisted) from the new PCB through the case.

15.) Ok, seriously. You can do this. Mate the plastic part of the field coil assembly to the metal part making sure to match up the marker line(s) you made. Carefully slide the field coil assembly over the shaft (armature).

16.) Replace the motor parts into the shell. To do this you will need to make sure the black boot (about the size of a few stacked nickles) is placed over the end thrust bearing (the thing that holds the shaft end and allows it to spin).

17.) With some trial and error, you should be able to slide all the parts into their registration points in the case - refer to the many pictures you took! There is a little spring force that needs to be applied near the collet release mechanism. Also, make sure to position the threaded tube at the end of the drill so that it looks as in the photos.

18.) Check to see that the shaft spins somewhat freely.

19.) Attach the AC cord to the two flat head connector blocks and tighten until snug - do not over tighten.

20.) Now you will route the three wires into the wire channels in the shell and position the PCB into the holding slots.

21.) With the PCB in roughly the right position, replace the strain relief block using the two long torx screws. At this point things should stay in place fairly well.

22.) Double check the alignment of the motor parts, and PCB to see that it matches the photos - adjust as needed. The blue switch bar should be in position and should be able to operate the microswitch properly.

23.) Position the speed adjustment assembly and the cover into the correct position.

24.) Fit the top shell and carefully over the bottom shell, aligning the internal parts to their registration points. The two halves should mate easily and there should be no internal parts left. Before screwing it together, squeeze the shell closed firmly and verify that the motor spins freely.

25.) Replace the case screws and tighten snugly - recheck that the motor still turns freely.

26.) Screw on the collet cover end cap, just snugly.

27.) Replace the hanger

28.) Install the motor brushes and end caps - just snugly not too tight.

29.) Make sure the drill switch is in the off position and no tools are in the collet. Plug it in the out power outlet and switch on the drill. It should operate normally and check the speed control for proper operation.

30.) Turn off the drill and insert a tool to make sure that the collet clutch is correctly assembled.

Enjoy. BTW, this request for me to tell how I did it had to be done from my memory, since I had actually already fixed the drill. I tried to think of everything, but my apologies if you encounter something unexpected. Sorry I didn't video it or take pictures - I never think that anyone cares about this stiff until afterward. Good Luck!

1. Remove the brushes.
2. Remove the wire bail and the case screws.
3. Separate the clamshell and remove the power cord.
4. Remove the armature and unplug the stator.
5. Remove the power cord wires from the circuit board.
6. Remove 3 circuit board wires from the brush holder.
7. Reassemble.

Replaced variable speed control

Removed case on Dremel tool and removed faulty switch. Then replaced it with new printed circuit board with switch.