[Milsurplus] [Boatanchors] Probably OT: Drill press runout question

[hwhall at compuserve.com]

Thanks to all for the info and suggestions. Looks like I need to (a) upgrade my chuck hardware and (b) get some of the PC board bits with the larger shank diameter. For now I was able to complete the  prototype board drilling using the excellent ideas of tape and heat shrink tubing. The bit was too tiny to get the tape wrapped onto it right but I had some suitable sized heat shrink tubing. The bit slowly slipped inside the tubing at first, but taking a hint from the tape idea, I remade it with some GOOP glue on the bit's shank under the heat shrink tubing and that seemed not to slip anymore.

Thanks & 73 to all,

Wayne
WB4OGM



 

-----Original Message-----
From: David Knepper <collinsradio at comcast.net>
To: milsurplus <milsurplus at mailman.qth.net>; boatanchors <boatanchors at mailman.qth.net>; hwhall <hwhall at compuserve.com>
Sent: Tue, Apr 29, 2014 4:43 am
Subject: Re: [Boatanchors] Probably OT: Drill press runout question


Try shrink tubing



David Knepper - W3CRA/W3ST
Collins Radio Association
www.collinsra.com
Join the CRA today
-----Original Message----- 
From: hwhall at compuserve.com
Sent: Monday, April 28, 2014 10:46 PM
To: milsurplus at mailman.qth.net ; boatanchors at mailman.qth.net
Subject: [Boatanchors] Probably OT: Drill press runout question

I need to drill some very small circuit board holes for a project, #64 drill 
size (.036 inch). My drill press chuck wouldn't grab a bit that small, so I 
got a mini chuck to fit into the press. The mini chuck shank is 1/4 inch. 
When I installed the mini chuck, the drill bit wandered in a circle, like a 
case of runout. Not like a bent bit, the whole length of the bit was moving 
around. But when I put a 1/16 inch bit into the drill press, there isn't any 
runout anymore.

Thinking the mini chuck to be faulty, I looked around the workbench some 
more and found a hand drill that would grab the #64, and it ran true when I 
turned it, so I removed it and inserted it into the drill press. It had a 
5/16 inch shank. This combination also showed wobble. But the drill press 
still will turn a small diameter drill bit without noticeable wobble.

It's as if the wobble turns up only when the drill press chuck is made to 
hold a larger diameter, and goes away with the smallest diameters. Does that 
make any sense or suggest something that I should inspect or adjust?

Thanks!

Wayne
WB4OGM
______________________________________________________________
Boatanchors mailing list
Home: http://mailman.qth.net/mailman/listinfo/boatanchors
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Boatanchors at mailman.qth.net

List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com **


This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html