Shifter hole size driving me crazy

[nick7405]

I went to install the shifter and first was going to drill the holes out to 3/8 to accommodate for the TKO shifter bolts.....however I am know through 2 drill bits and still haven't successfully drilled out one hole..

Recommendations would be great lol

[toadster]

start with a smaller bit and work up - or use a step drill bit - should solve your problem :)

[Bob Cowan]

If I'm understanding this right, you're drilling out the holes in the shifter base plate?

In most cases, that is hardened steel. It can be very difficult to drill.
- make sure the drill bit is very sharp. Either new or use a bit sharpener.
- high quality drill bits only. No WM specials.
- Slow drill speed, moderate pressure.
- Frequent application of cutting oil.
- Excess heat is what kills the drill bit; stop frequently to let bit air cool.
- As soon as it stops cutting, stop! Sharpen or get a new bit.

Or, get a carbide burr and hog them out.

[Hoooper]

Oil+low speed and lots of pressure

[capt1black]

Just went through it myself. 3 bits, lots of water and oil and still lots of smoke and burnt wood but just pushed through it until it went through. Glad to know it was not just me.

[Papa]

Are you drilling the actual shifter handle? I did mine in about 30 seconds with a drill press and some tap fluid on the slowest RPM setting.

Edit: My shifter is the 427 shifter from ********** (mild steel) I suspect. If you're drilling the FFR shifter, it's stainless steel.

Not all drill bits are created equal. Use one that's best for the material you are working with:

https://www.grainger.com/know-how/industry/metalworking/kh-which-drill-bit-does-the-job#:~:text=DRILL%20BIT%20MATERIALS&text=Cobalt%20(HSCO)%20is%20considered%20an,of%20t he%20drill%20bit%20materials.

[nick7405]

Well, just spent 40 bucks on drill bits, will let you know. Thanks

[Hoooper]

Drill press makes a huge difference for drilling hard materials since it allows you much more consistent speed control AND more ability to put consistent force. Most common issue with handheld drills on hard material is too much speed. If you have a 2 speed drill put it in the low speed setting to keep from getting too much speed

[nick7405]

Went through a total of five drill bits, two of mine and three I purchased but they are drilled. Thanks for the advice everybody139042

[rich grsc]

I just used the correct sized bolt.:p

[Papa]

I just used the correct sized bolt.:p

The TKO shifter stub is threaded.

[Jeff's First FFR]

Great tutorial on drill bits, thanks,
Jeff

[toadster]

just to chime in on this, great ideas in this thread :)
I used a brand new DeWalt 3/8" bit, and cutting oil - held the shifter handle in a vice with a soft cloth - slow and steady, re-oiled 2x per hole

test fit felt really tight, so I reamed the holes ever so slightly - but fits perfect

185760

[42Bfast]

To add to this conversation,

As many discovered, stainless steel will work harden when it gets hot.
Thus, as several described, when one is cutting or machining stainless you must have sharp tools, go slow, and keep the workpiece cool.
If you can do that stainless cuts readily.
However, if not done correctly and hardens, it’s like my father used to say, “It feels like you are trying to grind down a stone with a stick “