View Full Version : how to slot the head of small screws ?

05-23-2011, 11:38 PM
I was making a replacement screw for a B&S vernier caliper face , 0-80 thread with a head diameter of .125 .
the screw works fine and I slotted the head with thin cut off wheel of a dremel tool but it looks a bit home made .
now the question is now in my mind of how do you slot head of a small screw so that it would look professional and what tools or cutters are thin enough to do really small screw slots .
thanks Brice

05-23-2011, 11:40 PM
I just slit small screws with a jeweler's saw. You can get blades in several thicknesses.

05-24-2011, 12:42 AM
There is this: http://www.brownells.com/.aspx/pid=18694/Product/SCREW_SLOT_FIXTURE

05-24-2011, 12:51 AM
About the smallest screw you can readily hold with it is a #4, around 3/16" long, and the guides are designed for .025" files or saws.


05-24-2011, 01:30 AM
never messed with jewelers saws , but a little research and a visit to www.riogrande.com has solved that lack of a tool in my shop .
the Brownells jig is a neat idea , I think I will make one that will work with smaller screws (added to the ever growing list things to make :D )
thanks Brice

05-24-2011, 03:25 AM
Not really HSM'able, but I recently cut some screw head slots on some REALLY tiny screws for some unknown restoration project on my wire edm machine. Customer wanted .015" max slots in these micro-tiny brass screws he brought me. I used .004" wire, so I had plenty of room to move and make a nice square slot.


05-24-2011, 06:58 AM
I work with almost every small sized screw there is for my model work. What I do is make small threaded bushings from brass, usually from hex stock so they cam be clamped in my dividing head or vise. When I get the screws made I screw them into the bushing, chuck it in the dividing head or vise and slit them with varying thicknesses of jewelers or slitting saws. It does a real nice job.

05-24-2011, 09:39 AM
Too much bother rigging up a milling setup to slot a few screws. Jeweler's saw works fine unless you have a lot of them to slot.

05-24-2011, 11:38 AM
That's why I designed the Brownells unit the way I did...and there are other tools that they still sell that came from the same way of thinking.


05-24-2011, 02:52 PM
You can make the tiny slots pretty easily on a mill, by using it as a manual shaper.

Drive the screw into a block or clamp it between two softer blocks of metal or plastic, in the mill vise. Take a 1/16" diameter round, grind one end to a chisel point with a tiny flat end. Grind a "hook" in the cutting face, and some relief on the sides. Put it in the mill/drill chuck and with the spindle not rotating, stroke the tool bit back and forth over the head, while lowering it .0005" or whatever each time.

If you want really tiny Phillips screws,,, uh,,,, somebody else can answer that one. :D

Mike Hunter
05-24-2011, 03:34 PM
I just finished up a bunch of loading gate screws for Winchesters. Made an aluminum fixture that would hold about 15 screws at one time, it clamps on the head (that way it wouldn’t booger the threads).

Ground a keyway cutter to .020, and slot them in the BP; takes no time to slot. I had 300 to do, great job for my 12 YO boy.

The screws have a ¼ in rad to the head. I drilled & tapped a 5C emergency collet, using a collet chuck & a form tool in the lathe; take about 5 seconds to radius the head. Just the loading & unloading is what eats up time.

05-24-2011, 06:05 PM
That's why I designed the Brownells unit the way I did...and there are other tools that they still sell that came from the same way of thinking.

brilliant design.:)