Need help drilling metal rods on center - International Association of Penturners
     International Association of Penturners
Pens for Service Members
 
Support The IAP

Go Back   International Association of Penturners > Community Forums > Metal Lathes
  Forgot Password
Register FAQ Members List Search Today's Posts Mark Forums Read


Logged on members can hide ads!

Welcome to penturners.org!

You've found the home of The International Association of Penturners. You are currently viewing our site as a guest, which gives you limited access to view discussions, photos, and library articles.

Consider joining our community today. You'll have full access to all of our content, be able to enter our contests, find local chapters near you, and post your questions and share your experience with our members all over the world.

Membership is completely free!!

If you have any problems with the registration process or your account login, please contact us.

Reply
 
LinkBack Thread Tools Display Modes
Old 02-28-2018, 12:23 PM   #1 (permalink)
 
Join Date: Oct 2014
Location: Burbs of Atlanta,Georgia
Posts: 432
Photos: 0

Default Need help drilling metal rods on center

OK folks, I am wanting to continue turning some pens from metal, Aluminum, Copper, Brass--I have been able to make several I am pleased with using pieces of Cigar Pen kits to finish them--where I am running into trouble is with getting a dead center hole drilled for a small bit-i.e. 7/64" for the tip of a refill.
I have been through about 6 small center drills, the tip of them keeps breaking off in the metal piece I am attempting to drill, so far only copper. These center drills are of questionable quality, I bought several sets through Amazon and they were all cheap in price...but having said that I have tried several speeds and in all cases I was feeding the bit in very slowly--I have only been successful in getting one hole drilled dead center, and on that one the center drill didn't break-so maybe that's the key, but I just can't seem to get one of these center drills for a small bit not to break, and once that happens I have to scrap the entire bar of copper I was working with! My headstock and tailstock are aligned beautifully, but if I just try to drill a hole with just the drill bit, they are hideously misaligned.
I would like to be able to achieve this without having to go to a metal lathe, I have been satisfied with the shaping I have been able to achieve on the several I have built, but on all these, I installed a brass tube in a larger hole I drilled through the middle of the bar stock and then trued the pieces up to match the bushings for the pens. I am really trying to figure out how to get the center drilled for now!!

Any help/info is appreciated!!
Fish30114 is offline   Reply With Quote Top
Old 02-28-2018, 12:43 PM   #2 (permalink)
 
Join Date: Aug 2010
Location: Bartlett, IL 60103
Posts: 544
Photos: 37

Default

Instead of a center drill try a spotting drill. They don't have the tip lie a center drill.


Sent from my iPad using Penturners.org mobile app
__________________
Regards,
Mike
Likes: (1)
Penultimate is offline   Reply With Quote Top
Old 02-28-2018, 01:06 PM   #3 (permalink)
 
thewishman's Avatar
 
Join Date: Mar 2006
Location: Reynoldsburg, Ohio, USA.
Posts: 7,881
Photos: 0

Default

A collet chuck in your headstock would hold the blanks better and more precisely.
__________________
Chris

Non Impedite Raditioni Cogitationis.
(Unencumbered by the thought process.)
Tom and Ray Magliozzi
thewishman is offline   Reply With Quote Top
Advertisement
Old 02-28-2018, 01:09 PM   #4 (permalink)
 
Join Date: Jul 2013
Location: Owensboro, KY
Posts: 285
Photos: 0

Default

Mike is right. Spotting drills are the way to go, but you aren't going to walk into Home Depot or Lowes and pick one up.

What you are trying to do is to locate the center of your piece with a non-flexible drill for the bit that is going to drill your hole. (I know you already know this). In reality all you need is just a shallow divot for the tip of your 7/64 bit to engage. That said, try using just the tip of the center drill (the very short wide angled part before the straight section) which is, in effect, a very small diameter spotting drill.

As far as drilling copper itself goes, if you google it, advice on practical machinist and other sites is all over the place. I've got nothing for you on that score other than to say that I believe that copper is a real bear to machine.
This is not based on experience, only from reading online. I think that I would move to a free machining (or even non free machining) aluminum or brass. I really think that your material is a big part of your problem.

http://www.onlinemetals.com/app_groups.cfm?step=2&id=2

Hope this is worth what you paid for it.

Bill

Last edited by bmachin; 02-28-2018 at 01:31 PM.
Likes: (1)
bmachin is offline   Reply With Quote Top
Old 02-28-2018, 01:47 PM   #5 (permalink)
 
Join Date: Nov 2015
Photos: 4

Default

When I was researching Beryllium I found that 145 Tellurium copper alloy is a free machining alloy. I didn't purchase any because of the price.
Maybe you could look into it?
__________________
-John-
Terredax is offline   Reply With Quote Top
Old 02-28-2018, 02:03 PM   #6 (permalink)
IAP Activities Manager
 
mredburn's Avatar
 
Join Date: Jul 2009
Location: Fort Myers FL
Posts: 8,157
Photos: 83

Default

Breaking drill bits and problems with holes that are not centered are usually an alignment problem. Put a dead center in your head stock and tail stock, a live center will do in the tail stock. push the tail stock up to close to the head stock and see if the points are perfectly aligned. Put a used credit/gift/debit card or thin wood 1/8 or less between the points and put a little pressure on them by advancing the tailstock quill slightly. Does the card remain straight up and down perpendicular to the lathe bed and does it remain straight across or does it tilt or angle in any direction when viewed from the top and side? That will tell you if they are really aligned or not. Most breakage is from misaligned tail stocks, you may have to hold yours left or right as you lock it down.
Make sure your drilling with the rod in as close to the jaws as you can. If the rod is bent slightly it could wobble enough to break the drill bit. A collet chuck would be better than a 3 jaw chuck for this.
If there is any slop in your quill travel the copper rod may be grabbing the drill bit and breaking it.
Drill chucks have different tolerances for repeatability and alignment. Its not likely the issue but it may be a cumulative problem. What are you using for cutting Oil when you drill?
__________________
Life occasionally offers us the opportunity to make very very hard choices. I have had such offers.
Level 6 Pen Wizard, smoke, mirror and sleight of hand enabled.
Mike.
http://www.silverpenparts.com
mredburn is offline   Reply With Quote Top
Old 02-28-2018, 02:13 PM   #7 (permalink)
 
Join Date: Nov 2015
Photos: 4

Default

Quote:
Originally Posted by mredburn View Post
Breaking drill bits and problems with holes that are not centered are usually an alignment problem. Put a dead center in your head stock and tail stock, a live center will do in the tail stock. push the tail stock up to close to the head stock and see if the points are perfectly aligned. Put a used credit/gift/debit card or thin wood 1/8 or less between the points and put a little pressure on them by advancing the tailstock quill slightly. Does the card remain straight up and down perpendicular to the lathe bed and does it remain straight across or does it tilt or angle in any direction when viewed from the top and side? That will tell you if they are really aligned or not. Most breakage is from misaligned tail stocks, you may have to hold yours left or right as you lock it down.
Make sure your drilling with the rod in as close to the jaws as you can. If the rod is bent slightly it could wobble enough to break the drill bit. A collet chuck would be better than a 3 jaw chuck for this.
If there is any slop in your quill travel the copper rod may be grabbing the drill bit and breaking it.
Drill chucks have different tolerances for repeatability and alignment. Its not likely the issue but it may be a cumulative problem. What are you using for cutting Oil when you drill?
Sometimes this doesn't work.
The points might align when pushed together, however, when the tailstock is pulled away from the headstock, there could be misalignment. This could be cause by alignment of the headstock to the ways, the ways not parallel, slop in the tailstock, and even alignment issue of the tailstock to the ways.
My neighbor has a piece he places in the headstock with a perfectly aligned center spot/tiny dimple, and he puts a morse taper fitting with a laser in it to check headstock/tailstock alignment from time to time, at any distance apart. It works very well.
__________________
-John-
Terredax is offline   Reply With Quote Top
Old 02-28-2018, 03:50 PM   #8 (permalink)
 
Join Date: Jul 2013
Location: Owensboro, KY
Posts: 285
Photos: 0

Default

Don,

Can you describe the part you are trying to make and the procedure you are using here? I understand that you are trying to drill the hole for the tip of a ballpoint or rollerball refill to come through, but what is the whole part? Is it a separate grip section? Is it one piece with the pen barrel? Is it just a 3/8 or 1/2 inch long tapered cone?

I'm not sure what you're trying to align. I sounds like multiple setups with a woodturning chuck.

It may be easier in terms of alignment to drill it from the inside. That might require fabricating a special bit or fixture to hold one. However that shouldn't be too difficult if you go ahead and get the ER collet chuck you were talking about.

FWIW
Bill
bmachin is offline   Reply With Quote Top
Old 02-28-2018, 04:39 PM   #9 (permalink)
 
randyrls's Avatar
 
Join Date: Feb 2006
Location: Harrisburg, PA 17112
Posts: 3,964
Photos: 61

Default

Quote:
Originally Posted by Fish30114 View Post
I have been through about 6 small center drills, the tip of them keeps breaking off in the metal piece I am attempting to drill, so far only copper. These center drills are of questionable quality, I bought several sets through Amazon and they were all cheap in price...but having said that I have tried several speeds and in all cases I was feeding the bit in very slowly
Don; Turn at High Speed (1000 RPM or more) and use lubrication (tapping/cutting oil).

Peck drill and use lube with each peck.
Don't buy them from Amazon, Little machine Shop has good ones and they sell individual sizes, not sets of various sizes.
__________________
Randy S.
~~~~ Add Your Postal Code and Country to the UserCP ~~~~~

I expect to pass through this world but once. Any good, therefore, that I can do or any kindness I can show to any fellow creature, let me do it now. Let me not defer or neglect it for I shall not pass this way again. -- Stephen Grellet
randyrls is offline   Reply With Quote Top
Old 02-28-2018, 04:42 PM   #10 (permalink)
 
Join Date: Jul 2007
Location: TX, NM or on the road
Posts: 1,516
Photos: 0

Default

I found that I can buy plumber's thread cutting oil locally and it works good on steel. I have also used Dexron II auto trans fluid. In my limited experience the latter is as good as the higher priced cutting oils.
Likes: (1)
dogcatcher is offline   Reply With Quote Top
Related Content
Logged on members can hide ads
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


All times are GMT -5. The time now is 06:03 PM.

Powered by vBulletin® Version 3.7.6
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0

Content Copyright © 2003-2018 by Penturners.org, LLC; All Rights Reserved
Terms Of Service   Acceptable Use Policy