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[email protected] Searcher7@mail.con2.com is offline
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Default Hougen Magnetic Drill Problem

On Friday, April 12, 2013 2:40:52 AM UTC-4, Wild_Bill wrote:
I believe Jeff is steering you in the right direction. Worn brushes and

weakened brush springs can lead to intermittent/no contact between the

brushes and the commutator bars.

With something softer than a hammer head (block of wood for example) tap on

the left side, then the right side of the drill motor housing near the top,

tryinng to power the drill after each side is tapped.

If this method results in the motor running, it's liely that the brushes and

springs may need replaced, but cleaning the brush holders may allow

sufficient brush contact.. but the parts may still be required for a proper

repair.



When removing brushes, it's a good practice to keep them apart so they can

be put back in the holder they came out of.. and also to scratch a small

mark on a long side of the brush to indicate the top or end of the motor so

they can be put back in the correct orientation.



Aside from loose connections or brush problems, it appears as though the

motor is turned on/off by a relay on the circuit board. A click noise mat be

noticeable when the start-stop buttons are pressed.

Checking for correct operation of the relay can be performed a couple of

different ways.. definitely check it with the power cord unplugged if you

aren't familiar with working on powered equipment.

If the relay doesn't appear to be reacting to the start-stop buttons, it may

be faulty. If you can desolder the relay to remove it from the board, it can

be checked out-of-circuit with an ohm meter and small power supply or

magnet.



For testing with power applied, only if one is experienced and familiar with

safe testing methods.. using a 120V light bulb instead of the motor,

connected to the circuit board motor leads would allow the relay check to be

performed without the additional concern regarding rotating parts during

testing.



--

Cheers,

WB

.............





wrote in message

...

I have a Hougen Magnetic Drill that is not working.

http://i290.photobucket.com/albums/l...pse1f7add1.jpg



The Magnet itself seems to work, but the drill portion doesn't. Not counting

when it turned on a couple of times two days ago, making me think that there

was a possible intermittent break somewhere in the connections.



I opened it up and tinkered with the safety switch adjustment screw, but

that wasn't the problem.

http://i290.photobucket.com/albums/l...psf865d83a.jpg



The safety switch is located on the bottom of the drill. The bottom of the

drill must be flat against the metal surface in order for the drill to power

on. (See the two buttons at the bottom):

http://i290.photobucket.com/albums/l...ps3e32a032.jpg



The third button in the center is I believe also a safety switch that will

cut power to the motor if the drill's magnetic base drifts as much as 1/2".



I assumed that there is nothing wrong with the AC cord because the magnet

portion works, so using my Fluke 79III multimeter on the Ohm setting I

tested the start and the stop buttons. There was activity on the

Multimeter's display screen when I press either, so I assume that there is

no break, at least as far as where those leads connect to the circuit board.

http://i290.photobucket.com/albums/l...ps3495c450.jpg



Would it be plausible to re-flow the solder on the circuit board in case

there is a cold solder joint somewhere?



I can't travel several hours round trip to spend $65 an hour at an

authorized repair location, so any advice on how to proceed would be

appreciated.



Thanks.



Darren Harris

Staten Island, New York.


I did replace the brushes in the same holders they came out of, but *may* have put one or both back in upside down from how they came out.

Also,I only use my multimeters for the basics and don't really know their functions in depth. So I can only note whether or not the display changes and the number read-outs. But not necessarily what they mean unless I'm just measuring AC or DC voltage or something like that.

Thanks.

Darren Harris
Staten Island, New York.