Drill Press Cross-Feed Table

[etpm]

At one point in my life, I owned a machine shop. It had multiple CNC mills, a Bridgeport, a Hardinge toolroom lathe, an EDM, a complete sheet metal fabrication area, and a plastic injection molding machine. The CNC machine tools were high precision and with careful setup and control, parts were regularly made with +0 / -0.0001 inch accuracy. I think I know the difference in how machine tools and drill presses work and why. I'm not trying to make repetitive movements, hold locations, surface milling, or hold precision tolerances. This isn't true machine work.

I can make my metal bandsaw hold tolerances of 0.003 with 12 parts having a miter cut at each end. You'll have to take MY word for the fact that I know what I need to accomplish this task and you don't.

As a current owner of a machine shop, one with several drill presses, I think it doesn't really matter which cross slide table you get. Your real limitation is the drill press. I have a bunch of drill presses. Most are OK and get used for jobs that only require precision in depth control. like installing Heli-Coils using a Procunier tapping head. Even my very nice drill presses with precisely fitted quills I would not consider milling with . This is for several reasons, but the two main reasons are the Morse taper quills and the fact that the cutter, the 1/4 inch endmill, would be held in a drill chuck. Granted, you could be using, for example, a Jacobs ball bearing chuck in very good condition or an Albrecht keyless chuck, also in very good condition. Or drill chucks of similar quality. And I must confess to using Albrecht chucks and small endmills for light milling jobs. In a Bridgeport. It is bad practice. But I did it using my machines and tooling so it was my risk. I would never have tried a stunt like that when I was working for somebody. That said, I think using a drill press for the same job is asking for disaster. You could maybe get away with it, but I think if you try you will, at the least, be breaking cutters. I can imagine the vibration and side load on that Morse taper causing the taper shank to come loose and fall out of the quill. That would be real exciting. I am frankly surprised that anyone who used to own a machine shop would even ask the question. Especially someone who can hold .003" on miter cuts on his metal cutting bandsaw.
Eric

 

[BukitCase]

"why are you asking on a Tractor Forum?"

Probably 'cause all the machinist forums already banned him...

 

[3Ts]

This has been an interesting thread. I'm interested in metal work, but have a drill press and a welder (period). I was unaware of the issues with side loading Jacobs chucks, nor did it cross my mind about milling machines with round columns. So I appreciated all of you who answered. I learned some more today.

To the OP: Yes, you came across as rather snarky. I realize you asked a question, but the rest of the thread is about education - not just to answer your question, but to educate people like me as well.

 

[BukitCase]

3T's I'm glad SOMEBODY got something positive out of this thread; I know I didn't say WHAT the problem with round column mills is, so if you don't mind, could you share what YOU found? If you're not sure, I (or likely most of the OTHER responders) can elaborate... Steve

Edit - here's a thread from a (sadly, now deceased) fellow Texan that covers a heroic attempt at "changing a sow's ear into a silk purse", aka "fixing" a round column mill the hard way -

Rong Fu Mill/Drill head lift guide - Shop Floor Talk

Rong Fu Mill/Drill head lift guide Machining

www.shopfloortalk.com

Pretty sure you'd need to join in order to see pictures, but it's free (and worth every penny

 

[workinonit]

I've been looking for a good table myself. I bought a cheapo table that is a POC. It's sitting on the floor. I am NOT a machinist and don't want to use my Baleigh press for that but I would like to be able to mount a piece and drill several holes without having to remove the piece and do it with some measure of accuracy.

 

[BukitCase]

I have this one

Grizzly.com xy table - mine

But I bought mine about 20 years ago; at that time, IIRC it was made in Taiwan. Current ones are Chinese (and about $90 more expensive).

I thought it was too big for my DP, so it sat in its box under a bench for about 12 years, then finally found a home in my "MDVT" project, along with 3 different vises and a "mini" jib crane - "MDVT" stands for "Mag Drill Vise Table" - original, huh?

Been awhile since I used the MDVT, but the table's lead screws are ALSO either 8 or 10 TPI, forget which - still very useful for "semi-precision" hole placement - a few pics... Steve

 

[BukitCase]

Couple more... steve

 

[metalbender]

Have to add my two bits. Troll. Anyone having that much "experience" wouldn't be asking here for basic info.

 

[LD1]

Have to add my two bits. Troll. Anyone having that much "experience" wouldn't be asking here for basic info.

Kinda like if a lawyer came to a tractor forum and asking for legal advise.....then talking down to everyone who tried to help....while stroking their own ego about how great and smart they are....lol. makes no sense. That's the impression I get. Some people just cannot be helped.

 

[3Ts]

3T's I'm glad SOMEBODY got something positive out of this thread; I know I didn't say WHAT the problem with round column mills is, so if you don't mind, could you share what YOU found? If you're not sure, I (or likely most of the OTHER responders) can elaborate... Steve

No-one said what the problem with round column mills was and I have no experience with them, but after reading about the Jacobs chuck damage due to side forces and a mention that round columns are a problem I put 1 and 2 together to figure out that with a round column the side forces are going to cause the cutter head to rotate around the column which means cutting a straight line will be very difficult. It just never crossed my mind until it was mentioned that round was a problem.