Very Sensitive Drilling Tool

cathead

cathead

CATWERKS LTD
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Feb 7, 2013
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This little tool comes in really handy for drilling small holes. I saw it on a You Tube video by "Joe Pi of Advanced Innovations". A special thanks to Joe
for taking the time to make the video. Several of my Henrob(also known as Cobra 2000 or Dillon" welding tips were in bad shape so decided to make
some new tips. It turns out that the threading on the welding tips is metric and without any metric taps, making new tips didn't seem doable. My worst tip
was a #3 tip that was bent and pretty much unusable. Since it was in that condidion, I had little to lose in repairing it. After drilling out the tip to 1/4 inch, a
tip was made to press fit into the existing tip. My thought was to silver solder the tip on to the drilled out tip but that proved unnecessary as the press fit
was entirely satisfactory with the advantage of still being removable. I may get some metric taps so I can make my own tips as the factory tips are quite
expensive. Also a set of micro-size drill bits will be useful.

The tool is basically a jig to allow hand feeding of a small bit into the work using the lathe. The photos will make it more clear.
This tool works nicely on the old Springfield Lathe set up for collet work.

A test of the tip proved to be successful as the flame was as good as a new tip would be. I used it to repair a cast iron leg
on a friend's coffee table and it turned out great using some old cast iron piston rings for filler rod.

Maybe this information will be useful to some of you who have some torch tips that need attention. P1020055.JPG

Being able to"feel feed" the bit by hand makes drilling tiny holes quite easy, no broken drill bits!
P1020052.JPGP1020051.JPG
 
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Mikey,

I'm tempted to make a drill feed that will work on the mill similar to the Royal product. The only thing I will need
is a small chuck that pinches down on the fine drill shafts. I'm wondering if yours is spring loaded possibly. The
inside must be keyed or splined to drive the chuck. Using a mill for the drive would make a lot better setup
since I could run up to 4,000 RPM which would be an improvement over my lathe that maxes out at about 1,500.
 
The chuck is a regular 1/8" capacity drill chuck with a MT0 taper and it will hold the smallest wire size drill. The sensitive feed collar is spring loaded. You grab the knurled collar and push down to engage the drill. This allows for a very sensitive tactile control. Works good for when you need to drill tiny holes, and it will work as well in the lathe as it does on the mill.

Here is a video that shows how this contraption works:

Joe Pi has a different approach:
 
The Albrecht C15 with the Albrecht 1/2" spring loaded arbor costs $700. I payed a fraction of that, brand new.
I feel it is worth the money, especially how well it's made. The Albrecht sensitive feed arbor is very solid, well made, as you can expect from Albrecht.
The arbor has enough space so it can be easily removed with my Albrecht J0 removal tool. I bought the Sierra American sensitive arbor, but it broke when I tried to remove it from a small chuck. There wasn't any space for a wedge or tool.

These small chucks and sensitive feed arbors are perfect for small drills. I've been able to use without high RPM's. I don't use it very often, but when I need to drill and tap small holes, they are perfect for the job. To date, I have not broken one small drill bit.
 
I have a few different makers of the sensitive drill attachments. They are OK for small drill bits. But when you want to drill VERY small holes, they are not any good. Instead of helping you avoid drill bit breakage. They have enough run-out to break the bits on their own! And drilling true position is not going to happen. The attachment has just too many tolerances that are adding up and moving part clearances to make the attachment any good for very small drill bit work…Dave
 
I have a sensitive drill feed similar to the Royal one. I bought it about ten years ago from Enco and it came with a Jacobs JO chuck. I ended up taking it apart and just using the chuck and arbor.

I have drilled holes as small as .007" in the past. IMO, the biggest problem with drilling small holes is runout. Even .001" TIR is large when drilling holes smaller than .010". A #00000 center drill has a .010" tip and invariably the tip would snap as soon as the countersink was engaged if there was any runout. I made a miniature version of a Set Tru lathe chuck for both my lathe and for my mill. I could adjust runout to under .001" which greatly improved the life of small drills.

On deeper holes, chip clearance can be a big issue. My preference for small holes is carbide pcb drills. They are very straight and rigid. I will bring the drill down to the part and hold at just skimming the surface. I would watch the drill with a 50x microscope and if I saw any wobble, I would back out. Once a hole was started, I would change over to a HSS drill if I needed a deeper hole.
 
I have no experience with a sensitive drill driver, so can't comment on the above.

Having said that, I routinely drill .038 holes in aluminum with my drill press. I've removed the coil return spring and replaced it with just enough rubber bands to lift the quill. That way I can feel the drill in the work.
 
I have an Albrecht 0-1/8" (0-3mm) chuck in apparently unused condition. It has a precision sensitive feed with 1/2" shank made by the the H. C. Stanley Co. of Escondido, CA. I see very little information on that company or their products online, but the sensitive feed seems to be a high quality unit. No apparent through chuck or through feed capability. I have a bunch of small to tiny drills as well, but have not used the chuck or the drills -- so far... I think I paid around $30 for the chuck with sensitive feed. It was probably worth that price... :eek:
 
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