Can someone help me chose a motor for my hand drill?

[Silverhobbiest]

Background:
(I'm a beginner)
I plan on using PCV pipe for the main body. The drill's purpose will be to install screws into pre-cut groves (basically a motorized screwdriver). These screws will be only a couple centimeters tall so the motor will only need a moderate amount of torque and rpm. It takes about 3 turns to install these screws but i would like the fit to be tight so maybe a little more than that would be excellent. I would like this drill to be able to unscrew as well .

The problem:
I need to chose a small motor that has enough power/torque and rpm to screw in the miniature screws (as well as unscrew) without stripping the groves at a fast but controllable speed. The motor needs to be small but effective and precise. I'm just not sure what kind of motor fits these requirements. Please help?

 

[phinds]

Although we have a huge variety of talent and knowledge here at PF and you may well get a good answer from someone, I would think that a hobbyist forum would be a lot better place to ask such a question.

 

[Nidum]

Try looking up the technical details of commercially available powered screwdrivers to get some design ideas .

 

[CWatters]

Most small motors will be way to fast for what you need so some sort of reduction gearbox will be required. This will also increase the torque and that might cause problems. I think you need to look for an adjustable means of limiting the torque and this is a feature of many commercial electric screwdrivers.

 

[litup]

You could certainly do that as a project but just keep the PVC small, 2 inch diameter max. Like the guy said, you would need a good speed reducing/torque increasing gear box and some motors have that built in. A machine I work on has an RF tuning box to tune a 1500 watt RF generator to an argon plasma in a vacuum and the tuner motors are kind of like the old clock motors, the rotor spins a couple hundred RPM but the output is more like 1 so it increases the torque 200 times in that case, it tunes a 'Jennings Capacitor', no relation to the famous Flux capacitor:), it is a variable cap inside a vacuum and has a drive that takes quite a bit of torque and it doesn't have to spin very fast, output maybe 30 RPM or so. You want high torque and low RPM output. I would look for those kind of motors on Ebay or Amazon, they should be available.

 

[Spinnor]

It is not clear to me why a commercially available tool can not work, or cannot be modified to work for you?

https://www.google.com/search?q=ele...d=0ahUKEwjpzuCMq57RAhXIRSYKHctaD0AQ_AUIzwIoAQ

https://www.google.com/search?safe=......1ac.1.64.products-cc..0.13.498.MpqgppqobwQ

 

[berkeman]

The drill's purpose will be to install screws into pre-cut groves (basically a motorized screwdriver). These screws will be only a couple centimeters tall so the motor will only need a moderate amount of torque and rpm. It takes about 3 turns to install these screws but i would like the fit to be tight so maybe a little more than that would be excellent. I would like this drill to be able to unscrew as well

What is your clutch strategy? How will you switch the clutch mechanism to "locked" for unscrewing?

 

[Silverhobbiest]

What is your clutch strategy? How will you switch the clutch mechanism to "locked" for unscrewing?

I just planned on using a DPDT momentary ON/OFF/ON switch to reverse polarity. But being able to lock it woud be useful as well and I'm not quite sure how to do that.
As for how to make the clutch, I planned on using the chucks below since I have some handy. However, i'd prefer to use ones that looked like a hollow cylinder, (similar to the hand drills a user posted above) to make it easier to change bits. But since I can't order any
online, I'd have to make that by hand.