How do I drill a hole across the diameter of a rod?

[TOOLMASTER]

Hate to be around when that guy finds his pin in the weeds..

 

[Frank Ford]

am finding that the tooling and fixtures are the most interesting and creative part of this hobby.

Me, too. I made a cross drilling fixture that works positively every time on the drill press. A bit of overkill, but then it's the journey, not the destination, isn't it?

My V-block can handle 1/4" - 2.5" diameter, and is equipped with a variety of shop-made hardened drill bushings:





Here's a link to the full project in detail: http://www.frets.com/HomeShopTech/Projects/CrossDriller/crossdriller21.jpg

 

[Marco Bernardini]

One more way to skin a cat…
Make some small marks on the drill press table, like the photo below, bend a bit the rod to fit the trench and you'll instantly have the hole in the center… more or less.

(Must I add «just kidding»?)
Jokes apart, another way is to use a collet holder with a couple of opposite parallel sides (both 4 and 6 sides are good), like one of these: http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Collet-Fixtures
The center of the top side of the holder is easier to be found, and you can make a jig for your drill press, a sort of fence, to have the holder sliding until you get the right distance on the held rod.

 

[IanN]

Cross drilling using a drill press:

1) Put a faced off piece of bar in the drill chuck, and locate a vee block under the chuck

http://i219.photobucket.com/albums/cc210/ian-new/7 - cross drilling - 1/1-setup1.jpg

2) Position the vee block under the drill so the bar touches both sides of the vee - the vee block is now centred under the axis of the drill spindle.

http://i219.photobucket.com/albums/cc210/ian-new/7 - cross drilling - 1/1-locatingveeblock.jpg

3) Clamp up the job and start drilling (a Slocombe/centre drill is best to start the hole)

http://i219.photobucket.com/albums/cc210/ian-new/7 - cross drilling - 1/2-drilling.jpg


All the best,
Ian

 

[IanN]

+1

A new item added to my to do list.

Rather than make a crutch centre, you can use a vee block and angle plate:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/4-veeblockandangleplate.jpg

1) Using the lathe:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/2-lathewith3j.jpg

2) Remove the compound:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/3-removecompound.jpg

3) Mount vee block on angle plate and mount on cross slide:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/5-mountveeonangleplate.jpg

4) Press vee of vee block against the extended tailstock ram - the vee centre is now at lathe centre height and the vee is parallel to the lathe axis:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/6-setveeatcentreheight.jpg

5) Tighten vee block to lock at centre height:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/7-lockatcentreheight.jpg

6) Turn vee to face headstock, place a piece of round bar in the vee and press against the faceplate - the vee is now at exactly 90 degs to the lathe axis. Tighten up:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/8-setveeperptoaxis.jpg

7) Secure the job and drill:

http://i219.photobucket.com/albums/cc210/ian-new/Cross drilling - 2/9-centredrill.jpg


All the best,
Ian

 

[Marco Bernardini]

Cross drilling using a drill press:

1) Put a faced off piece of bar in the drill chuck, and locate a vee block under the chuck

What about a 90° countersink instead of a faced bar, so it fit better with the V block?

 

[IanN]

What about a 90° countersink instead of a faced bar, so it fit better with the V block?

Yes - I agree!

all the best,
Ian

 

[chips&more]

What about a 90° countersink instead of a faced bar, so it fit better with the V block?

Please be careful with that idea. The counter sink has a proud cutting edge, then everything behind it is relieved/with clearance. So the profile of the point is not on center and should not be used as a locating device, sorry.

Edit: never mind me! I was thinking of a single flute cutter when I wrote this. Because that is what I use when I counter sink holes. You should be OK with enough accuracy using a multi flute cutter counter sink.

 

[markknx]

this is what I like about our craft, multipal answer on how to do something some better some worst but none truley wrong. It more often comes down to what you have to work with. Mark

 

[JimDawson]

This is a fun thread. Lots of good ideas.

I just tried an experiment, never having done this before.

JPMacG, the original poster stated that he has a lathe and a drill press, so only using those tools I managed to put a hole on center of a 1 1/4 inch round bar, by making a drill bushing out of the same barstock.

I cut off a piece of the bar stock, then went to the lathe.



Then to the drill press. I don't have a drill press vice so I grabbed my grinder vise for this demo. I didn't drill this hole through because I didn't want to drill into my vice, but you get the idea.



If your vice jaws aren't tall enough to accommodate this setup, a piece of flat bar on each side and a c-clamp should work to support everything in the vice.