I think this is a troll post really. Any 120V drill I've ever had a part is either a clam shell or inserted type housings. Both use a part of the housing to hold the bearings and brushes. And the drive end of the motors shaft is a worm or helical gear, machined right into the shaft. All of this makes it pretty hard to use just the motor for anything else.

 

I think this is a troll post really. Any 120V drill I've ever had a part is either a clam shell or inserted type housings. Both use a part of the housing to hold the bearings and brushes. And the drive end of the motors shaft is a worm or helical gear, machined right into the shaft. All of this makes it pretty hard to use just the motor for anything else.

I tend to agree. This is the 22nd post. The TS hasn’t responded since post #3. In fact, he’s only posted twice in the entire thread.

 

I tend to agree. This is the 22nd post. The TS hasn’t responded since post #3. In fact, he’s only posted twice in the entire thread.

It's the way it is. Probably lost interest. Move on

 

It's the way it is. Probably lost interest. Move on

Hi, although sometimes the TS loses interest in threads the comments of those responding often interest me greatly (which is why I hang around here... ). I've never tried to run a 120V universal motor on DC 12V but I'm astonished if it doesn't turn at all! Possibly the torque required by the "quality" of the gear train when fitted in the drill might defeat it, but on its own? If it really was stalled and when first connected to something with the internal resistance of something like a car battery I'm imagining that it will never turn again because the windings may have got a bit hotter than they were designed for, since no back-EMF would have been available to limit current...

 

Hi, although sometimes the TS loses interest in threads the comments of those responding often interest me greatly (which is why I hang around here... ). I've never tried to run a 120V universal motor on DC 12V but I'm astonished if it doesn't turn at all! Possibly the torque required by the "quality" of the gear train when fitted in the drill might defeat it, but on its own? If it really was stalled and when first connected to something with the internal resistance of something like a car battery I'm imagining that it will never turn again because the windings may have got a bit hotter than they were designed for, since no back-EMF would have been available to limit current...

I would agree that as a reader you glean a lot of very useful information from the knowledgeable contributors. I wouldn't know a universal motor if I saw one.
It's just a shame when quite a lot of hard work goes into all the answers when the questioner can't do their bit by at least letting others know how they got on. It happens a lot on other electronics forums. A simple thank you often suffices.

 

I wouldn't know a universal motor if I saw one.
.

If you have a vacuum or central vac, you have used one.
Max.

 

Thanks Max
I really ought to get to grips with all these motors.
I think the only time I experimented was with a very old Wolf 240-V AC drill which had no speed control apart from the gearbox.
As far as I remember, I tried putting a largish diode in one of the lines, and I think it did work. Whether it worked well is another matter.

 

Some 120VAC drill motors will in fact run with 12 volts DC, BUT not if they have a variable speed function. AND, I have a small vacuum cleaner motor that spins up nicely on 12VDC. Of course most 120VAC drill motors, as stated in an earlier post, do use the drill housing as a big part of the motor frame, supporting both the bearings and the brushes. So they would be very hard to make work in any other arrangement.
I did not see what part of the world this TS was located in, so I can't comment on that part. But certainly the remark of "put it back together and return it for your money" was way out of line, since who would want a drill that had been taken apart and then re-assembled?
Battery powered drill motors are a different story alltogether, and my experience is that they draw a lot of current when under any load, which makes an external power connection to the drill motor a rather more tedious thing.

 

I would agree that as a reader you glean a lot of very useful information from the knowledgeable contributors. I wouldn't know a universal motor if I saw one.
It's just a shame when quite a lot of hard work goes into all the answers when the questioner can't do their bit by at least letting others know how they got on. It happens a lot on other electronics forums. A simple thank you often suffices.

I do agree with Phil-S, that a "thank you" certainly makes anyone who has invested a lot of time/effort feel rewarded... just wanted to add though that there are probably a couple of dozen others (who, like me, generally sit on their hands) who have benefited too.

 

Thanks Max
I really ought to get to grips with all these motors.
I think the only time I experimented was with a very old Wolf 240-V AC drill which had no speed control apart from the gearbox.
As far as I remember, I tried putting a largish diode in one of the lines, and I think it did work. Whether it worked well is another matter.

A drill I had (Black & decker I think) had a two speed switch which simply added a diode in series with the motor - very simple, very effective.

 

A drill I had (Black & decker I think) had a two speed switch which simply added a diode in series with the motor - very simple, very effective.

I was referring to those 120 volt AC powered drill motors with the phase-control variable speed feature. THAT will not work at all with DC.

 

I was referring to those 120 volt AC powered drill motors with the phase-control variable speed feature. THAT will not work at all with DC.

I have a Proxxon drill as the spindle on my CNC. This drill is fitted with a speed control which works when the drill is fed with AC, but when fed with DC it runs at full speed.

 

A drill I had (Black & decker I think) had a two speed switch which simply added a diode in series with the motor - very simple, very effective.

It may have used high speed on AC and placed the diode in series for half wave DC for low RPM.
Down and dirty!
Your Proxxon may have a Triac phase control before a bridge.
Both require Universal motors.
Max.

 

I have a Proxxon drill as the spindle on my CNC. This drill is fitted with a speed control which works when the drill is fed with AC, but when fed with DC it runs at full speed.

I am not familiar with the Proxxon tools, but clearly it does not have the variety of speed controller that I was referencing.

 

I am not familiar with the Proxxon tools, but clearly it does not have the variety of speed controller that I was referencing.

See the note about the speed control on this one:
https://www.proxxon.com/en/micromot/28462.php

 

See the note about the speed control on this one:
https://www.proxxon.com/en/micromot/28462.php

Here in the colonies we wouldn't call that a drill, even though it can be used as one. This is what we call a drill -

 

Here in the colonies we wouldn't call that a drill, even though it can be used as one. This is what we call a drill -
View attachment 175758

It is also common to call a drill bit a drill.

 

Yes that is true, but the Proxxon is commonly called a rotary tool or hand held grinder.

 

Yes that is true, but the Proxxon is commonly called a rotary tool or hand held grinder.

Proxxon's website calls it a 'precision drill grinder'.

 

Whatever.

It’s not a drill.

Dremel calls it a motor tool. I’ve heard all of the above names. Can be used as a drill, but...

It’s not a drill.