Jump to content

pencil drill

Recommended Posts

While on an obligatory trip to Home depot to pick up some caulking for the home reno, I took the opportunity to do a little grazing in the tool section, and came upon a small pencil engraver. this tool had a diamond burr for doing the engraving. Advertised as a standard 3/32 shank regular burr, with pictures for putting names on anything and everything. it was the 3/32 shank that piqued my interest, because I have a whole bunch of 3/32 shank miniature twist drills. It was also touted as 20,000 rpm, so fast.


It was $39 so I purchased one as compensation for having to go back to get the second tube of caulking which i should have purchased the first time there.




the yellow button is a momentary on switch.






I drilled a few holes easily with a .022" drill  it was true and smooth in its operation, and uses 2 AAA batteries.




So it will be very useful for small hand held applications.




Link to comment
Share on other sites

PROXXON has been doing something of similar size over here in Europe for many years, but it is a 12V cable-version:

Proxxon Graviergerät GG 12 Netzbetrieb

There was a problem with the take-up of the end-thrust by the motor-bearing alone, but I sorted this with a small metal disc at the free end of the electric motor.

Link to comment
Share on other sites


The General version has been on Micro Mark for a while.  There is a Jacobs chuck that fits it, so

wire gauge bits can be used with it.

Ah yes us folk who live on the outskirts of the civilized world eventually hear about these things, or stumble across them accidentally as I did. ;)



Link to comment
Share on other sites

This pen drill is nice, but still too long for confined spaces (like inside the hull).

Is there anything better than this ugly hack I was forced to make using the cheapest parts available?

I am pretty sure that there are smaller motors available, and batteries could be wrapped around it, keeping the body short.



Link to comment
Share on other sites

I have been thinking of adapting a dentist's angled drilling head ('hand-piece') for such purposes, but the problem is that it only takes short inserts with a fixed diameter. So one would need to construct a collet/chuck as well.


The problem with smaller motors is that they have higher RPMs in order to deliver power. Otherwise you don't get enough torque. This in turn needs a well-balanced chuck in order avoid vibrations. In your case I would replace the Philipps-screw with a headless screw (which is what these little collet-chucks come with anyway, as far as I know)

Link to comment
Share on other sites

2 hours ago, Mike Y said:

This pen drill is nice, but still too long for confined spaces (like inside the hull).

Mike an interesting point. I remember that Gerald Wingrove built himself a small micro drill years ago using a model train DC motor and if my memory serves me correctly it was pretty short as well. At the low cost of these on sale, as an experiment I might just chop it up and use a short flex power connection between the head and the battery part of the body.  It might be more trouble than it's worth, but on the other hand it might just be the ticket.



Link to comment
Share on other sites

Small DC motors with chucks =


AliExpress   a commune of sorts in China

Marlin P Jones   motors, wires , and a DC 2A power supply that is 3/4.5/6/7.5/9/12 V  with banana plug and gator clamp wires - no need for batteries

and speed control from power supply  @ $17  it would not take many batteries for it to be cost effective

Edited by Jaager
Link to comment
Share on other sites

Guessing that you are asking about AliExpress


Under  Home Improvement

is tool

try 12V DC motors

and drill chucks

also have water stones


They have low cost flex shafts with 1/4" sockets and chucks that mount there.

I needed for 1" / 2" / 3" bowl sander tools (hook & loop media mount)  ( PeachTree)- but I

bit the bullet and bought a Kirjes flex shaft from Lee Valley  to finish inside frame bevels

instead of the low cost Chinese  tools.


The cost is generally very low at Ali  - and mostly they are reliable - shipping is surface post and

not too long.   There were a couple of mistakes- and instead of a refund - I got some sort of something

for a cell phone - a device that I am mostly a Luddite about.  

Link to comment
Share on other sites

  • 2 weeks later...

As long as you make sure there isn't a burr on the cut end it should work perfectly.

I had the opposite problem with another brand of micro chuck - the shaft was too short to go into my dental drill hand piece so I ah do de-solder the one that came in the chuck and replace it with one a bit longer - no problem as it is a std size.


Link to comment
Share on other sites

  • 3 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Create New...