Cordless drill/tool that doesn't lockup when trigger released?

I need to propel a 6 inch wheel at about 5 mph. So I need a cordless drill or any light cordless tool that is geared to about 400 rpm. Unfortunately, the thing cannot include a device that causes lockup when the trigger is released and forward pressure appears on the drill shaft.

I'd like medium to high quality, but functionally like my cheap cordless Skil drill, with a clutch that works in both directions. But my Skil isn't powerful enough and doesn't include a low gear that tops out at 400 rpm or less.

Hopefully I can disable the braking feature on my DeWalt DC728 14.4 V drill. I disassembled it and got to mess with lots of gears but did not see the braking mechanism. I guess the braking mechanism is located in the one of the clutch pieces. It doesn't seem very modular, I'm not sure I could even use the geared motor without the clutch.

By the way.

Apparently DeWalt drills use MOLYKOTE grease. I see McMaster has several different types. What type of that grease or what other type of grease is suitable for drill gears?

Is handling that grease hazardous?

Thanks.

Reply to
John Doe
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The braking may be electrical. Shorting the motor terminals together when the power is disconnected will brake the rotor/armature. This seems to be what is done in my Bosch & Ryobi drills. My guess is that it is done in the trigger switch.

Even with the motor unbraked you will probably get significant friction/intertia as you will be driving the rotor (stepped up) back through the gearbox. HTH.

What are you tring to do? There are some reasonably priced geared DC motors around and reversing is not a problem.

Reply to
Den

The braking on my DeWalt DC728 must be more than electrical. Try putting a 3-5 pound weight with significant centrifugal force in the chuck, get it up to speed, and then release the trigger gently as possible. When I do that here, it binds and serious grating/grinding happens. After finally getting around to testing the thing, I find a drill with such a braking device is a complete nonstarter for my project. Uhg.

Yeah, I think that's what happens with my cheap Skil drill, but the clutch works in both directions which relieves some of that braking force.

I'm ready to click on any links. DC motors with about the same amount of power as a 14.4 V or greater cordless drill, and low geared to about 400 rpm or less.

Cordless drills/tools come in a nice neat package with a trigger switch and a battery holder, for a reasonable price.

Thanks.

Reply to
John Doe

For a one off job verge shop a large office photocopier, most of the ones I've stripped have had a great 12/24V gear motor in them. Alternately someone like:

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but on your side of the world could probably help. For an ongoing source googling for local suppliers may be the solution.

Yep, I use a couple of old cordless drills in rigs for repetitive tapping - they work a treat and are cheap.

Reply to
Den

Does it really need to be cordless? Because it kind of sounds like you need a lathe.

Reply to
LEGEND65

Why not purchase an over-running clutch bearing. They are identical dimensions to a standard bell bearing, but transmit torque in one direction only. In the other direction they are a free running bearing. They are usually about 50% more expensive than an equivalent bearing. They are readily available here in Australia, so you should have no trouble locating one at any reasonably good bearing supplier such as SKF or NSK

Reply to
Grumpy

(snippage....)

You might try poking around

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to see if they have anything that may be suitable. While I don't have extensive experience with them, I have made small orders once or twice and have absolutely no complaints at all.

Reply to
Andrew Erickson

I've spent money on that route before. Difficult to match attributes include environmental contamination, locking torque, and inner\outer diameter. I'd love to use clutch bearings, but so far no go. I might try again.

Reply to
John Doe

Apparently clutch bearings do not support radial loads. That's another problem.

Reply to
John Doe

John. I have 14 new in the box Torrington RC-061008 roller clutches. They are ID 0.3750, OD 0.6250 and length of 0.500. The current price I found was $4.96 each. I would sell them for $2.00 each plus shipping.

I own an electronic assembly service. Years ago when we stuffed leaded components into holes in circuit boards, we had a machine called a component sequencer. It cut components from reels and put them onto new reels in a specific order for an inserter machine to insert them. The sequencer used rotary solenoids to advance and cut one component at a time from the master reel. One direction of rotation could be used, but the solenoid had to return to its resting position. The roller clutches were between the solenoid shaft and the cutting/ advancing mechanism.

We sold the machines, but seemed to have forgotten a box of clutches. I just found them the other day.

Would these be of any interest to you?

Paul Drahn, President Jodeco, Inc. Redmond, Oregon

rollerblades.http://www.flickr.com/photos/27532210@N04/2565924423/

Reply to
co_farmer

Do they function under a radial load? Can they be used in a dirty/dusty environment? Uhg. Too bad I don't have engineering experience in everything I want to make.

FWIW. This is not a prototype for a production, it's probably just for me. I'm looking at cordless drills with a two-piece chuck (as opposed to the ordinarily much more desirable single sleeve ratcheting type). Apparently the crummy two-piece chucks do not include a locking mechanism on the shaft. I ordered a Skil 18 V drill without batteries dirt cheap for $20 total. I'll plan to use some 18 V lithium-ion batteries if that drill will work. If possible, maybe even better would be to use a 36 V lithium-ion battery for which I already have a battery holder and charger, somehow electrically splitting it into two 18 V halves. Then again, ack, that 36 V battery requires a special trigger switch with output properties that will have to match the 18 V Skil motor. And then that trigger switch probably won't work with the 18 V battery half I envision making out of the 36 V battery. So I'll have to buy another lithium-ion cordless drill kit just to get the batteries, the holder, and the trigger switch for use with the 18 V lithium-ion batteries (assuming all lithium-ion batteries have more than positive and negative output leads). So I might settle for NiMH. Or whatever.

Reply to
John Doe

No, I don't think any roller clutch will function with a side load. That would make the rollers want to twist and quickly wear the housing or the ramps that give the clutch action. And they are not sealed. They have grease internally, so dust would not be good.

You may need to incorporate both bearings and clutches in your design.

If I may suggest something. Work on engineer parts or sections of your design. Don't worry right now about power, speed, batteries, etc. Just get the mechanical part to work. Then begin to apply power. See what needs to be changed mechanically, then when that works as you want, step up the power, voltage and what ever you want. Engineering is not a one step operation it is is working through the problem over and over until you get it right.

Good luck. Sounds like a fun project.

Paul

Reply to
co_farmer

That's exactly what I was going to suggest. Bearings to control loads and clutches to drive

Since the project was never identified, it sounds like school is in session.

Reply to
B A R R Y

Anything is possible, Barry.

See the first sentence of my original post, Barry, are you grasping for excuses to avoid helping anybody?

Reply to
John Doe

...

Here's a description by Skil:

Reply to
John Doe

Google rec.woodworking especially finishing. Come back when you can demonstrate how I don't help very often.

"DEN" asked for more details, and you ignored it. You're going to turn a wheel, we can read that. The actual application might allow others to provide even more help.

Building a Battlebot for school?

Reply to
B A R R Y

I don't really know or care, Barry. Why do you assume others are asking about schoolwork? Why does it matter to you, Barry?

Even if I did ignore it, who's problem is that, Barry?

Did you read that, Barry?

Are you dissatisfied with the amount of help I've been given, Barry?

Reply to
John Doe

Reply to
B A R R Y

Uhh... I hate to jump into this since I see that the OP is being cagey, and kinda rude.....

So I won't offer any suggestions other than to say, have any of you who answered bothered to click on the link he sometimes (I'm sure accidentally) left on a few of these posts... reproduced here for those that lost the original posts...

Reply to
Dave August

You have an 0-470?

NNNNNNNNNiiiiiiiiiiiiiiccccccccccccccceeeeeeeeeeeee!!!!!!

The flying Harley!

Reply to
B A R R Y

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