[OCCRA]: drill transmission

[greencactus3]

our hand drill. which weve been using for a couple years, (exactly the same one we are using for this years robot) is starting to go bad i think... and im hoping someone can help us fix it maybe..
problem 1) the shifter is stuck in 3rd gear.. literally jammed.
problem 2) the clutch, even when its in the drill setting, slips quite easily. i can hold on with my hand, and in 3rd gear(well, cant test the others) i press the "throttle?" and the clutch goes....slips....

i have never actually looked at the clutch, and have no idea if its just starting to wear down or whatever... and the jammed 3rd gear... well i guess i should take the whole tranny apart? id rather ask first tho. as its still usable for light applications.
and i dont exactly know how the gear shifting thing works.... it switches by twisting parrallel to the axles(gears, the spinny part. not axle.. whaddya call it?) and not perpendicular as the ones were like last year...

anyone who can help us fix this would be greatly appreciated! thanks!

[Mr. Mac]

We have done a lot of autopsies on the old Bosch drills and became fairly adept at fixing them (we developed a tub full of spare parts as the seasons wore on) but have not done any on the Dewalts yet; I think if you were to ask this question in a few weeks we would be able to help you, but not right now. Hopefully, somebody out there has tackled this already and can be of some help...

[MaxBraverman]

Well....I am not sure if you are talking about a) a drive motor hand drill for the robot or if you are talking about a "hand drill" as in one you use to build or b) if you are talking about a DeWalt or Bosch drill motor.

If you are talking about a DeWalt that you are using to build your bot, then I may be able to help you out with your gear problem. I own a DeWalt 18V 3 speed drill/hammerdrill that I have used in construction work. Not too often it would physically resist changing speeds but was easily corrected. All I did to shift the gear was either 1) Drive in a screw or start to drill a hole, then as soon as you release the trigger, attempt to slide the shifter, or 2) start the drill motor going slow (do not apply any force on it in terms of driving a screw or anything for this technique), and try to shift it out of the 3rd speed setting as the drill is going VERY slow. There is a danger of damaging your transmision with the second way, however it has worked for me before when my drill wouldnt switch.

Hope that my suggestions helped you out,

Max Braverman
Team 180

[greencactus3]

Originally Posted by MaxBraverman

Well....I am not sure if you are talking about a) a drive motor hand drill for the robot or if you are talking about a "hand drill" as in one you use to build or b) if you are talking about a DeWalt or Bosch drill motor.

If you are talking about a DeWalt that you are using to build your bot, then I may be able to help you out with your gear problem. I own a DeWalt 18V 3 speed drill/hammerdrill that I have used in construction work. Not too often it would physically resist changing speeds but was easily corrected. All I did to shift the gear was either 1) Drive in a screw or start to drill a hole, then as soon as you release the trigger, attempt to slide the shifter, or 2) start the drill motor going slow (do not apply any force on it in terms of driving a screw or anything for this technique), and try to shift it out of the 3rd speed setting as the drill is going VERY slow. There is a danger of damaging your transmision with the second way, however it has worked for me before when my drill wouldnt switch.

Hope that my suggestions helped you out,

Max Braverman
Team 180

we got the jammed gear selector to move now. now just the problem of the clutch slipping... this is for the dewalt one.
and both the drill transmissions of handdrill and the drive motor are slipping.

[Mr. Mac]

Originally Posted by greencactus3

we got the jammed gear selector to move now. now just the problem of the clutch slipping... this is for the dewalt one.
and both the drill transmissions of handdrill and the drive motor are slipping.

Something is probably preventing the clutch plates from seating themselves fully. I'm assuming that you have the torque collar set to the drill position (as marked by the icon on the collar) and not one of the torque settings. If the transmission was ever taken apart, you might open it back up and see what pushes the plates together; in the Bosch drills we used to use there were ball bearings that, if dislodged from their nests, would prevent the plates from engaging. Make sure that nothing is inside and that the clutch plates still have the clutching indentations facing each other. In the meantime, I've sent a new drill to your school.