Drilling a Hole in a Round Shaft Can be Easy and Accurate

[Tom Wesenberg]

Let's say you buy U bolts to secure the rear spring, and they come too long, so you cut off the extra length, but now you need to drill a hole for the cotter pin. Buy a hex nut and scribe crisscross diagonal lines across the 4 corners of one flat side. Now center punch the exact center of that flat, which is where the lines cross. Clamp the nut in a drill press vice and be sure the flat is perfect horizontal, then drill a 1/8" hole through the nut. Now you can screw the nut onto the U bolt and drill an accurate hole for the cotter pin. Again be sure the nut and U bolt are perfect horizontal.

It might even be easier and a little more accurate to repeat the scribed lines on 2 opposite flats, then drill one side at a time. Then screw the nut onto the U bolt and drill from one side half way into the bolt, then drill the other side all the way through.

[2manycars]

Nice tip. It might be necessary to run a tap through the nut to clean any burrs from drilling.

[Brian in Wheeling]

Don't really know what your saying...Four corners on one flat side...what the heck is that? Flat side of the nut? one of six?
B.

[DaWizard]

Brian, the whole sentence is "Buy a hex nut and scribe crisscross diagonal lines across the 4 corners of one flat side."

The "One Flat Side" is one of the sides on a hex nut. The faces on a hex nut are square.

[Mitch]

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[DaWizard]

Crude but effective

[BNCHIEF]

Mitch is already celebrating new years early.

[Tom F]

Let's say you buy U bolts to secure the rear spring, and they come too long, so you cut off the extra length, but now you need to drill a hole for the cotter pin. Buy a hex nut and scribe crisscross diagonal lines across the 4 corners of one flat side. Now center punch the exact center of that flat, which is where the lines cross. Clamp the nut in a drill press vice and be sure the flat is perfect horizontal, then drill a 1/8" hole through the nut. Now you can screw the nut onto the U bolt and drill an accurate hole for the cotter pin. Again be sure the nut and U bolt are perfect horizontal.

It might even be easier and a little more accurate to repeat the scribed lines on 2 opposite flats, then drill one side at a time. Then screw the nut onto the U bolt and drill from one side half way into the bolt, then drill the other side all the way through.

I just have a inexpensive HF drill press. How would I be able to hold a nut tight to drill it. Is there something to buy that will hold it to the table part?

[Brian in Wheeling]

O.K. I see now, thanks for helping with the pic. Tom, you'd need a drill press vise to hold the nut.

[tbirdtbird]

you could prolly hold it effectively with a pair of vise grips. Be sure to have a really sharp drill bit, it will go much easier for something this delicate, and be sure to center punch the mark first. If the bit is dull, and you have to compensate with more pressure, the nut will want to walk around the table.

Remember, the tools that are most likely to harm or cut you are the dull ones....because you will push harder, then it will be more likely to slip and cut your finger. You use so little pressure with a sharp bit this is way less likely

You could even use a bolt threaded into the nut as a handle, then start drilling some, to get a starter hole, then remove the bolt, then hold with vise grips

[cpf240]

Might want to use some cutting oil as well as adjust the drill press speed for the job.

[Mickey]

If you use a bolt to hold the nut to be drilled use a second nut to jam lock the first one in place. Then you can use vice grips, C clamp, vice, wood clamp, etc. to hold it down for drilling.

[Tom F]

Thanks guys, I see what you mean now. Do they make a drill press vise to attach to the table part?

[tbirdtbird]

yes, with some you attach to the table using c-clamps

[Tom F]

After posting I looked on Google and seen what a drill press vise looked like. Seen one from Lowes for $20.00 which would work great for what I would need it for. Trying to hold things with pliers will be NO more.

[Dennis]

The one at Harbor Freight is a piece of crap from what I see.