Drilling steel sphere on drill press

[Philip Davies]

I know that there is a proper way to do this, who will be the first to tell me?
I want to drill holes in steel ball bearings to make tommy bars for clamps.
This is the method I devised

You see that I have filed a flat prior to centre punching.
I have taken a hex nut, cut through one flat, and half way through another. Then I hammer the ball bearing into the nut. It looks central to me, but I have no way of checking. Then I squeeze it in the drill vice

Tap it down so that, as far as I can see the flat is at right angles to the drill bit. The nut is supported by a scrap of beech off a chair, that has a countersunk hole in it.

Not sure that you can see, but I’ve drilled about halfway through the ball. I shan’t tap it, but epoxy a bar in the hole.
Now, all you engineers can have a good laugh!

[mklotz]

Here's how I usually do it...

Sphere drilling jig

Works for the brown stuff, too...

Drilling holes in spheres

[mr mikey]

If it works for you and it functions as you intended that's a good thing. An idea I will keep in mind. Thanks. Mr. Mikey.

[dbat74]

Whatever works for ya. Most times we work with what we have. Looks good to me.

[Frank S]

I agree with use what you have and what works for you is best for you. There are times when you have to get really creative on project design challenges. Once I had a space frame construction project this particular space frame design was a screwed together tube and ball which was a series of varying length tubes with tapered down ends connected to spheres at just about every angle imaginable

The spheres ranged from 4" to 6" in diameter the supplier of the tubes and spheres sent everything assembly ready tagged and numbered as per the construction drawings the rub was the customer's requirements had changed after the order had been shipped as was the norm for the Middle eastern way of doing business, we muddled through the project by re drilling a few of the spheres chucked up in a lathe to accommodate the changes
Then I designed a jig for drilling holes in the spheres at different angles should we ever encounter this situation again or start making our own space frame materials here is a jpeg of the assembly drawing. By drilling and taping 1 hole in a sphere on a lathe it would then be bolted into the fixture and could be rotated in just about any conceivable useful angle without having to remove it

[Toolmaker51]

Good as the suggested examples are, not sure Mr. Davies has the equipment for approximating these.
Phillip, I'll recommend a step to add.
Locate center before grinding the flat, with a small true running pointed pin (even a reversed bit).
Stop the spindle, eyeball the center from 2 ~ perpendicular perspectives.
Place a 6" scale or straight shim between pin-point and sphere, the coinciding axis will be apparent with that blade in apparent level.
Clamp the vise into place.
Clamp something to stationary jaw, acts as a stop to reposition the nut & clamped ball.
Felt-tip mark which face used of the hex, to assure re-attaining same position.
You should now be able to make however many needed, with good visual 'centered-ness'.

I have NO clue how you are managing to 'file' or drill a true bearing ball, they are upper most Rockwell hardness. I suspect these are more a roller or detent of some type.

[Philip Davies]

I said steel ball bearings, but actually they are mice balls! Ie steel spheres, which were rubber coated, which were formerly used in computer accessories. Thank you for the suggestions.

[Toolmaker51]

Mice balls will be in short supply, once ASPCA gets wind of this . . .
Meanwhile computer trac-ball are still the ultimate interface. This laptop is thumb driven pointer, almost as good, compact to move.

[dbat74]

Well I suppose
u could put them in a lathe 3 jaw chuck and you have the center automatically.