How To Drill Round Stock On Center When Too Large For Spindle

[martik777]

Stock is both too long for the bed and too wide for the spindle bore. What are some techniques to drill a fairly accurate hole in the end? Drill press is too short as well.

 

[RJSakowski]

Hmm, too long for the bed, too large to go through the spindle, too long for the drill press. It sounds like a job for the hand drill.

How close to center do you need to be (also, for reference, what are the dimensions of your piece)? There are a number of methods of scribing the end of a round bar to find the center.One is to lay the bar on a flat surface and bring a block that is approximately the half the height of the diameter. Scribe a line; try to keep the scribe oriented in the same position. Rotate the bar 90 deg. and scribe another. Continue twice more. The center will be midway between the scribed lines. With careful work, you should be able to get within 10 thousandths.

You can also use a try square with a centering head but if you do, use four lines as above. Mark the center lightly with a prick punch and then center punch the mark. Use care when drilling and try to keep the drill in line with the bar axis.

Or find a friend with a larger lathe.

Bob

 

[JPigg55]

Here's a link to a method of finding center of a circle using a right triangle, http://www.mathopenref.com/constcirclecenter2.html
Has an animation to demonstrate method.
For drilling, might try turning a shorter piece that will slide over the end of your stock snuggly. Center drill a guide hole with the drill bit the size of hole you want. Then use a hand drill inserted through the guide hole.
Once again, not exact, but should be close.

 

[Tony Wells]

Question. If it is longer than the bed, and larger than the spindle hole, how are you going to work the piece?

 

[Ulma Doctor]

depending what's right in front of me ,
i'd either use a hermaphrodite caliper set to 1/2 of the stocks diameter and scribe the center of the stock from 4 places from the OD
OR
if i wanted to cheat a little, i'd blue the approximate center, then use my dial calipers set to 1/2 Diameter and scribe the center with one leg of the dial caliper in 2 places at 90* to each other

good luck

 

[martik777]

I ended up making a tight fitting sleeve with a guide hole. Finding center was not so much the problem as needing to drill straight.

I think if I clamped it down to a v block attached to the tool post and used the lathe as a horizontal drill, that would work too.

Tony: I did not need to work it, just needed the hole in the end.


Thanks all

 

[turnitupper]

Use a plunge router,Carefully.
John.

 

[ch2co]

Martik

Perfect solution! Just the kind of thing that I would have thought of..... several days too late.

Chuck the grumpy old guy

 

[Ripthorn]

I was just going to respond with what Martik said. It's a wonderful solution, I've done it before.

 

[The Liberal Arts Garage]

saw saw

Stock is both too long for the bed and too wide for the spindle bore. What are some techniques to drill a fairly accurate hole in the end? Drill press is too short as well.[/QUOTE. Did you wonder what
Those stiff- joint calipers with the miss- matched ends were for ? Put your work on
something as flat as you can find, approximate a big pair of v- blocks,wood, a try-
square, wood chisel, etc. Mark the center with the calipers. Level the workpiece
With a real v- block shimmed up to the diameter of your drill (level everything),
Use a straight- edge to sight sideways.Get a good start and " balance" the drill.
A helper wih a good eye makes it easier..........BLJHB