How do I go about making a Torx security bit?

[Pcmaker]

I want to make a screwdriver bit, around 4" in length with a 1/4" hex profile, with one end being a T25 Torx bit and the other being a T20 Torx

I have an idea on how to make it, but I don't know what cutter I need make the grooves. I was watching a youtube video of a CNC cutting and it looks somewhat like a gear cutter. I guess I can measure the groove with a gage pin and see what fits the best. It doesn't have to be exact as it just needs to fit into a torx screw and the tolerance doesn't have to be exact. I plan on using 1045 CR as I will be able to anneal it while machining and harden after I'm done.

 

[T Bredehoft]

Worst case, grind a single form tool to fit (HSS) and fly-cut it.

 

[markba633csi]

Fortunately Torx is 6 lobed so you can use hex stock without needing a dividing head. The flycutter idea is good
You might need a better steel than 1045 like O1 ? or maybe 4140?
-M

 

[jbltwin1]

Buy one of each, mig weld them together and grind flats flush. Sorry, just the easiest thing I could come up with! Mike.

 

[Pcmaker]

Buy one of each, mig weld them together and grind flats flush. Sorry, just the easiest thing I could come up with! Mike.

Yeah, I did that and use it all the time at work

I couldn't stop thinking how I would go about making one out of one piece, though

 

[derf]

It would make more sense to me to start with the right size torx bit and cut a slot in the end with a thin dremel cut off wheel.

 

[RandyWilson]

Fortunately Torx is 6 lobed so you can use hex stock without needing a dividing head.
-M

Not all. Torx Plus is a more rounded lobe. Security Torx Plus is five lobe. Ask anyone that's tried to disassemble a MAF from an E39.

 

[markba633csi]

Standard Torx is six, I assumed that's all he was needing. I knew there are others

 

[Z2V]

@Pcmaker
Does it have to be 4” long? This is 2” long, came from Grainger

 

[whitmore]

I want to make a screwdriver bit, around 4" in length with a 1/4" hex profile, with one end being a T25 Torx bit and the other being a T20 Torx

Yeah, getting a particular form of Torx screwdriver would be nice... I'd think in terms of O1, drilling the
security holes on a lathe, roughing out the tips, then hardening. Finish with EDM , or
by grinding with abrasive slurry and rotating copper formed tool (jewelry-carving style grinding).