Drill Press Chuck Runout

Anyway - if that hole is under 1/16" out then I can compensate a little by reaming it a little larger, but any more than that I have to square up the material again to the bore before doing anything else. A "true" hole would save me a couple hours easy.

If you are drilling a stock blank and have to work the blank after drilling anyway why does the hole have to be so good? What is the extra 'couple hours' for if the hole is not 'true'?
 
I've been wrong before and I'm sure I'll be wrong a lot more down the road, but my gut tells me you have more of an alignment issue than a chuck run out problem.

Do you have a dial indicator you can mount either in your chuck or on the spindle? If so, I would suggest mounting it and take a reading against the three sides of that channel in your jig you put your work pieces in. Run it up and down against the sides as far as you can. It needs to be very close. I personally don't think that laser is a good enough way to line things up within a few thousands so your holes will meet in the middle head on.

Again, I could be wrong, but these are the things I would be looking at before buying a new chuck just to possibly find out I have the same problem after doing so.

Ted


I am using a dial indicator to test for runout - it is there in the chuck body.

It certainly can be a combination of runout and alignment. I've never really been happy with 'the fixture'

I suppose mounting 2 indicators on a bar in the chuck would allow me to mic the whole length of the fixture & not just the top 3" - though it is a plywood and maple jig - sooooo not super smooth, flat or true. But it certainly sounds like a faster setup than futzing with the laser.

though I guess I could also grab a length of aluminum angle stock or use some setup blocks ..... that stock needs to move along the fixture, drill 3" move the stock, drill another - flip, drill 3" move the stock ... Lots of things can be happening there.
 
If you are drilling a stock blank and have to work the blank after drilling anyway why does the hole have to be so good? What is the extra 'couple hours' for if the hole is not 'true'?

The next operation would be 'roughing' out the barrel channel with a router. The barrel and mag tube need to be absolutely parallel to one another. So I need an edge on the work to be absolutely parallel to the hole center.
 
Agreed.
The correct tool geometry for the material... technically for my application into the end grain, a forstner type bit would be ideal, but they just don't make em that long :(

Would an auger work ? Apart from the threaded tip it has the same geometry as a forstner bit.
 
Sean, I looked into how the wood turner guys bore lamp holes and they use a lamp auger, sometimes called a shell auger. Supposedly, it bores a straight hole in wood and might work better for you if you can hold the work piece in the lathe. Here is one such bit: https://www.amazon.com/DEWALT-DW168...&qid=1539030527&sr=8-3&keywords=auger+bit+5/8

This has got to be better than trying it in a drill press. A drill bit will deflect in a deep hole that long, no matter how careful you are. This auger has a shape that will hopefully keep you centered.
 
Would an auger work ? Apart from the threaded tip it has the same geometry as a forstner bit.
Yes augers do work & I have used them - mostly in the ramrod holes. the drawback for them is't use power to run them ... :( you also need a starting hole to keep them accurate.
 
Sean, I looked into how the wood turner guys bore lamp holes and they use a lamp auger, sometimes called a shell auger. Supposedly, it bores a straight hole in wood and might work better for you if you can hold the work piece in the lathe. Here is one such bit: https://www.amazon.com/DEWALT-DW1681-8-Inch-17-Inch-Auger/dp/B00004RGZC/ref=sr_1_3?ie=UTF8&qid=1539030527&sr=8-3&keywords=auger+bit+5/8

This has got to be better than trying it in a drill press. A drill bit will deflect in a deep hole that long, no matter how careful you are. This auger has a shape that will hopefully keep you centered.

Yes - I have delved into the deep hole thing extensively. Lamp turners, pepper mill makers, flute makers all need to make deep holes - but they don't need to be particularly accurate as all they do after is mount the piece between centers after an ~voila~ the hole is centered by accident... :(

What you have there is a ship auger - a shell auger is quite different, no center spur and a very shallow cutting angle - they almost grind. they are specifically designed for cutting into end grain but you don't see them any more since the advent of the forstner ...

The next best option I really have is creating some tooling so I can do this on the lathe.
 
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