Overhead Drill Press Design Ideas Sought

[Farrell]

A wheel with bearings and axle might just be the ticket. I think some have axles that are only a couple inches long, and then just bolt up to something. Maybe even a trailer wheel assembly. I could over-tighten the bearings just a tad so there is no wobble at all (that would also allow adjustment in the resistance to turning). Hmmmmmmmmmmm. Thanks. Will report back.

Terry Farrell
  
----- Original Message ----- 
From: "Robert Goodale" <rrg@unlv.edu>
To: <pianotech@ptg.org>
Sent: Sunday, April 21, 2002 1:03 PM
Subject: Re: Overhead Drill Press Design Ideas Sought


> I might suggest you poke around your local auto salvage yard.  Sometimes 
> you can find a variety of doo dads there which can solve problems.  In 
> terms of the swivel issue an old idler pulley comes to mind.  If you can 
> find one that can be mounted and bore holes through the pulley to insert 
> screws for the other end you might have just what you need.
> 
> A more beefy system might be a complete wheel assembly from a very small 
> car.  Using the brake rotor as a mounting plate might work perfectly and 
> would certainly provide a lot of stability.
> 
> 
> Rob Goodale, RPT
> Las Vegas, NV
> 
> Farrell wrote:
> 
> >I completed my first incarnation of my overhead drill press. Why do I say first incarnation? Because, after giving it a test run yesterday poking a few holes in an old pinblock, whereas I feel it is quite adequate, it is clearly not as good as it could be with a few modifications. The main deficiency is wobble in the system, 98% of which originates at the swivel.
> >
> <SNIP>
> 
> >#3 is where most of my wobble comes from. This swivel is very rigid when you hold it in your hand and try to wiggle it, but when you load it with 100 lbs. and give the weight some leverage, it has a lot of motion (the bearing are in about a 4" diameter circle). I have thought about these television turntables, but I am not sure they are any better. I have also thought of mounting a large (maybe 16" by 16") 1/4" thick FLAT steel plate on one side of my swivel and put several Teflon slides (with up/down adjustment) on the opposing surface near the perimeter of the steel plate. I think it would work, and would rob the present system of the leverage thing. Any better ideas? The best would be to find a large (between 12" and 18" or so) steel ball bearing turntable that works in a tension application - rather than a compression application.
> >
> 
> 
>