Drill Press Needs Help

I have a floor model drill press that is .045 off from front to back on a 5 in rod. I can true it from side to side but not from front to back. To get this I chucked a 1/4 in rod and left 5 in sticking out and measured. I realize this is less than 1/16 and on most drilling it wouldn't matter but with pen blanks I thought it might need to be true. Is this enough to matter? If it is how do i fix it?

Thanks Ray

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Ray Cody
Florence, AL

A 1/16" is a lot and would matter significantly on pen blanks. Not sure what the solution might be. What kind of drill press is it? If fairly new, contact tech support of the manufacturer.

Name on drill press is Ludell, mfg date 1984 and made in Tiwan. Press was a gift and is in good shape except it wont drill straight. I thought there might be a jig that could be made to fit on the bed that would adjust this out. I figured if it was out there someone here would know. I may have to buy a new one but that will be after all else fails.

Thanks Ray

yarydoc said:

Name on drill press is Ludell, mfg date 1984 and made in Tiwan. Press was a gift and is in good shape except it wont drill straight. I thought there might be a jig that could be made to fit on the bed that would adjust this out. I figured if it was out there someone here would know. I may have to buy a new one but that will be after all else fails.

Thanks Ray

Click to expand...

That's tough. All I can think of is maybe shim the collar for the table support. Or shim the head on the column.

Since this is probably only a problem for your penturning activities you might be able to just shim in a correction on your pen drilling vise.
For example if you use one of the standard centering vises (or PHD vise like me) you could mount the vise on a sheet of plywood. If the plywood was approx 5 inches wide (front to back) from the center of where the drill will hit and put approx .054" in shim on the edge closest to you (5" from center) then that should about equal out the error of the drill press. I made an assumption on which direction the press is off so if it is the other way around then the shim would go in the back.

Now if your drill press has any place where you can add shims underneath that would be a more permament solution, but it didn't sound like you have that option.

This is a problem that I have given some thought to as the table on my drill press has the same problem. I never went so far as to measure the actual amount it was out as it has never given me a real problem. (I use a machinist's vice to hold my blanks and only have to tip the blank a little in the vice to have it line up perfectly parallel to the drill bit.)

I have looked pretty closely at my DP and have never come up with a way to shim the head or the table collar that I thought would be an effective and permanent solution to the problem. It's true, as others have suggested, that you could mount your vice on a plywood base and shim it to be perpendicular to the drill bit; but this is only a half-a**** solution to the problem and the error would still exist for any other type of work that you were doing on your drill press.

Were it me, I would get a piece of 3/4" or 1" plywood and cut it to the size of the DP table or larger and then bolt that piece of wood to the DP table and shim it in the process so it was perpendicular to the drill bit. That way you would have a surface that was perp. to the drilling axis regardless of what you were drilling.

That being said, it may be that you really don't have a problem at all. Consider that you have an error of 0.045" in 5 ". If you look at the kits that are commonly available, about 95+ per cent of then have barrel sections that are about 2" long. The error you quoted above translates to 0.018" in 2" or just slightly less than 1/2 mm.....a negligible amount for most pen crafters. Only place I can see where that might be a problem is drilling blanks for Celtic knots or other detailed segmented blanks. I've never done a Celtic knot so I don't know exactly how much of an error is allowable before the effect is noticeable in the final product.

A better way than shimming the plywood on top of the table is to drill a couple of holes a smaller diameter than a couple of 1/4 in screws. Make a recess for the screw heads. You will have to do an educated guess on the length of the screws - but the point is - with a screwdriver, turn the screws until they come out the other side and begin lifting the false top into a level position relative to 90° of the drill bit.

Precision is in both the process and the equipment. The old machinist generally sought to get the equipment close and then used consistent process to achieve the precision needed. There are trade-offs between the two approaches, and the ability to work equipment will vary with the other uses you make of it.

Most floor stand drill presses have a movable platform that adjusts on the column that holds the head. You can shim the mounting fixture, but tend to lose the shim settings when moving table up or down.

For most cases, an auxillary drill press table is capable of being trammed to 0.01 inch or so with use of melamine coated MDF surface. Double thickness like a router table or workbench will reduce deflection. Fasten this to the metal drill press table and get some shim stock (as in brass or beer can stock). Fasten the table down firmly and tram the table.

Put a piece of wire into the chuck and into a Z with one leg of the Z in the chuck and the other end pulled down to just clear the table. Rotate the chuck by hand and note where the high and low spots are at. Losten the fasteners and add shims to raise the low spot about 1/2 to 2/3 of the difference between high and low. Resnug the mounting hardware and re-tram the surface. Repeat several times until the table is consistent as you check all the way around.

Keep the wire as you will need to re-tram the table evey time you take the auxilliary table off or move the table up or down on the shaft (and you want to keep the table at 90 degrees to the axis of the chuck.

Thanks everyone, that gives me some options. I'm glad I didn't get the only whop sided drill press in the world.



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Ray Cody
Florence, AL