Squaring drill press table to bit.

[Howard Riley]

Gentlemen,
I blundered into a very easy, but foolproof, method of squaring the drill-press table with the drill bit—assuming that you have a lathe. Behold!

Step 1. Turn a piece of stock (that has been squared on the tale end) to the size of the center hole in the table. Then, about a ¼ “ from the end start a slight taper (to facilitate insertion and removal in and from the hole) for about 1 3/4 “ and separate from stock.

Step 2. Insert cylinder in center hole.

Step 3. Insert small bit or sharply pointed rod into the chuck, then lower the bit into the depression made by the tale piece, which will be in the absolute center. The table is now square wit the bit. Amen!

Step 4. Remove cylinder and save.

Note. Whether or not the table is square with the base makes no difference, it will
be square with the bit. Let me know how you like this method.
.

[Doug Garson]

Can't picture how this will ensure the bit is square to the table only how it centers the table on the bit. How deep is the depression made by the tail piece? My current drill press table doesn't tilt but my previous one did. I used a steel rod and digital tilt box gage to square the table to the bit.

[jack forsberg]

This is what I do but a bent wire in the chuck will do too

[glenn bradley]

Another bent wire guy here.

[Jim Morgan]

Start with a 12" length of 1/8 brass rod, chuck it in the drill press or lathe, and use a file to make a point on one end. Bend the rod in a Z shape, chuck the unsharpened end and check for equal clearance (or equal sound) while rotating the quill with the pulley.

[jack forsberg]

Another bent wire guy here.

it is easy glenn . for those follow along at home goggle tramming a table

[Myk Rian]

Bent wire here also.

[Mike Cutler]

I've used the same method Jack demonstrates in his video. It's the way I learned in shop class a zillion years ago.
I imagine the "bent wire" method is about the same thing.

[Charles Lent]

I'm also a bent wire user.

Charley

[johnny means]

Can't picture how this will ensure the bit is square to the table only how it centers the table on the bit.

Agreed. There is no reason why the bit couldn't hit the center of a tilted circle.

[Howard Riley]

Doug,

Thank you for your questions. Think of the drill-head arm and the table arm as being two lines extending from the center of a circle, one higher than the other. When the upper one is exactly above the lower, they are parallel, both latterly and vertically, and each is 90º from the center. If the table is square on its arm, it is also square with the bit.
The depression made by the tailpiece may be a dimple or ¼” deep; is not critical. Its location, which is in the exact center, is. Hope that I haven’t confused you, but if so, just ask. H. R.

[Simon MacGowen]

That guy's drill press table does not seem to be flat across and it won't matter how "square" he can set the table!

Frankly, I have not checked my drill press table for years and I have not detected any negative effect on my work. But this thread reminds me to do a check either with a bent wire or with Garson's method.

Simon

[Doug Garson]

Thanks for the response Howard, as I said my current drill press table doesn't tilt so I can't try out your method but I agree with Johnny that the bit could hit the center of a tilted circle. Have you tried the method you described and cross checked it with one of the other methods?

[Charlie Velasquez]

Thanks for the response Howard, as I said my current drill press table doesn't tilt so I can't try out your method but I agree with Johnny that the bit could hit the center of a tilted circle. Have you tried the method you described and cross checked it with one of the other methods?

Yes, it could, but this is not a circle, this is a cylinder. The cylinder would be perpendicular to the slope of the table. If your table is fixed wrt the relationship between the center hole and the quill (centered over the hole) then it will always hit the center of the hole regardless of the slope of the table. (My 1970 Craftsman has a table that is just clamped to the post, I can rotate it in both x an z axis)
By introducing a perpendicular cylinder of x mm length, your drill point would still hit the center of the hole, if it could get there, but it will not hit the center of the top of the cylinder (if it is not square to the table).

Try it with your fingers. Make an inverted t with your forefingers then rotate your base, keeping them perpendicular. You have just moved the center of the top of the cylinder.

[Doug Garson]

Yes, it could, but this is not a circle, this is a cylinder. The cylinder would be perpendicular to the slope of the table. If your table is fixed wrt the relationship between the center hole and the quill (centered over the hole) then it will always hit the center of the hole regardless of the slope of the table. (My 1970 Craftsman has a table that is just clamped to the post, I can rotate it in both x an z axis)
By introducing a perpendicular cylinder of x mm length, your drill point would still hit the center of the hole, if it could get there, but it will not hit the center of the top of the cylinder (if it is not square to the table).

Try it with your fingers. Make an inverted t with your forefingers then rotate your base, keeping them perpendicular. You have just moved the center of the top of the cylinder.

I could see it working if you had a inch or so deep hole in the wooden piece the same diameter as the drill bit. Then the drill bit (with the drill press not running) would only fit if table was perpendicular to the chuck. Don't have a lathe but I picture the depression made by the tail piece to be a shallow cone shape so that's why I don't see it working. Can't follow your idea with the inverted tee with your fingers.