Centering hole in vent liners

[carlv]

Hi all,

First off, thanks a bunch for all the info you guys provide on here. I've learned a ton since I found this board.

I'd like to make my own vent liners. I've read all the old posts I can find on this, especially the ones in the tips section.

One question I have is that since I'm a little bit "machinist challenged" is..... how do I go about centering the hole in the screw when I go to drill it?

I do have a little bench drill press which works just dandy.

Thanks!

[edge]

IMO, with most hex head screws the center of the hex is relieved and the drill should start centered.

edge.

[9point3]

Screw your screw into some nuts. Get youself a short section of strait allen wrench that fits the screw and chuck it in your drill press. Place your screw/nut combo on the section of allen wrench. Take your drill press's vice and open the jaws(don't clamp vice to table). Run your quill out a until the screw/nut can be grabbed by the vice and then tighten the vice around the screw/nut and then clamp the vice to the table. Now loosen the chuck, replace allen wrech with drill bit and drill away. Works well with any roundstock that will chuck up in your drill

[Harley]

Although centering is the ideal way to go, don't worry too much about it. Just lower the drill bit to the screw before turning on the press, and eyeball-center the bit. If you drill off center, it doesn't matter as long as the hole comes out the bottom; i.e., it's not lost in the screw threads.

Harley

[carlv]

Feb 25, 2009 12:58:19 GMT -5 9point3 said:

Screw your screw into some nuts. Get youself a short section of strait allen wrench that fits the screw and chuck it in your drill press. Place your screw/nut combo on the section of allen wrench. Take your drill press's vice and open the jaws(don't clamp vice to table). Run your quill out a until the screw/nut can be grabbed by the vice and then tighten the vice around the screw/nut and then clamp the vice to the table. Now loosen the chuck, replace allen wrech with drill bit and drill away. Works well with any roundstock that will chuck up in your drill

Thanks 9point3, that actually makes sence to me

Thanks also, Harley and Edge, good info to know.

[rbinar]

8-)I find this is the best way to do it.

Before you start to call me names the mini-lathe cost no more than a good drill press and makes life a lot easier on occasion.

[youp50]

I have a piece of scrap aluminum that is 1/8 inch thick. I clamp it to my drill press table and drill and tap the hole to hold the screw. Now it is centered and all I need to do is put in a screw and drill away.

[Richard]

What I did was to take a piece of flat stock that is as thick as the entire screw. Drill the appropriate size hole and tap it 10-32. Then put a slight bevel (use a larger size drill bit) on it. The taper on the vent liner screw is 82* but don't worry about that. You just want the vent liner to sort of center itself when screwed in. Then just drill away.........The bit will find the center. Just make sure it does not bend and use some cutting oil to prolong bit life.
Richard

[Harley]

For those who aren't sure how to go about making a vent liner, here's an old thread that describes the process:

Go to the TIPS/HINTS and click on Topic 2, then scroll down to the vent liner reference.

dougva.proboards.com/index.cgi?board=Savage&action=display&thread=3364

Harley