[Boatanchors] Chassis Mechanical Question

[Mike A]

On Fri, Feb 14, 2014 at 03:56:27PM +0000, whitebear1122 at comcast.net wrote:

> Greetings. I have a mechanical question. I am in the process of drilling
> , milling, and hole punching several chassis's fo r my HBR-13 receiver
> project. I have all the holes punched except for threeoctal socket holes.
> I just discovered the octal ceramic sockets require a 1 1/4" hole and my
> Greenlee punch is 1 1/8". My question is this: Can I realistically file
> 1/16" all the way around with a rat tail type file and have the hole look
> clean. I'm worried I'll start filing and it will end up looking like crap
> or become goofy shaped. Is there some sanding barrel shaped attachment for
> a drill that would open the hole slightly and evenly?
>
>
>
> I wonder if anyone has a used Greenlee 1 1/4" inch punch for sale. I've
> got a nice selection put together so far, including 5/8", 3/4", 7/8", and
> 1 1/8". I've never used a punch before this and they have been fabulous!
> I did have to learn a lesson though. I was so darn careful to be precise
> in my layout drawing, and transferring those hole dimensions to the
> chassis. I used the recommended punch screw hole dimensions in the Greenlee
> instructions and then found out the holes didn't need to be that big, so the
> punch floated around too much and all the tube socket holes are slightly
> offset. Darn. Maybe it'll look better when I take the masking tape off.
> :) 
>

If you have a drill press, then one of the stepped drills with 1 1/4" and 1
1/2" steps will help you. Center the 1 1/4" hole on that step of the drill,
then carefully feed the step drill to get a 1 1/2" hole. Repeat as needed. You
may want to clamp the chassis so that it doesn't break loose and spin; I have
seen people lose fingertips trying to stop spinning things.

-- 
Mike Andrews, W5EGO
mikea at mikea.ath.cx
Tired old sysadmin