Need Help!- Covert drill press to milling machine

[GrievousAngel]

Hello All,

I too often need to cut straight edges and do plunge cuts into aluminum plate (1/8 to 1/4") or 1/16 to 1/8" steel flat bar, and end up using everything from hacksaws to rotary tools with metal cutting disc to oscillating tools. The plunge cuts would be mostly round, with some square holes and longer slots (1/8" x 6" for example). The longest edge cut would be straight up to 24", but if I flipped the plate, I could go 12" from each end.

I have a larger bench-top drill press with 1/2" chuck already to use. I do understand enough to know that it uses the wrong bearing type as it is not suited for loading in the x-y direction (axial loading I think is the correct term). I can also locate a suitable x-y table such as the Palmgren 49181 MTC18 Compound Milling Table or the Grizzly G8750 6" x 18-1/2" Compound Slide Table. I have a Bosch Colt rotary tool if it is a better choice in place of the existing drill press motor (so I would not have to replace the drill bearings with milling grade bearings). Then the question becomes where can I find a after-market Colt clamp or fixture that I could attach to the drill press pedestal. Tolerances of +/- 1/64th or better is OK for my applications. As you can see, I have several critical issues to solve, and that is why I am requesting help from the best web site I know of for these types of projects, CNCzone!

Summarizing:

1. Is this a good approach if I have the time and not lots of $$?

2. Is the Palmgren 49181 MTC18 Compound Milling Table a good x-y table choice or what is recommended? What about the Grizzly G8750 6" x 18-1/2" Compound Slide Table (cheaper than the Palmgreden)?

3. Where and what type of bearings would I need to replace the drill press bearings with? The drill press is a Lowes bench-top pedestal type w/ 1/2" chuck, belt drive (I can get model number if requested).

4. If better, where might I find a Bosch Colt adapter for something like this? I would think that the same Colt adapters used for table-top XYZ CNC's would be OK.

5. Some cuts may be blind (not through cuts) so I would need the means to clamp the cutting depth, again +/- 1/64 is certainly adequate.

6. Since some of the bar stock or plate to be worked, would be larger than my XY table, I would need to be able to manually flip the orientation of the material and re-clamp. This implies that T-clamps may not always work. Suggestions in that area is needed.

7. Is there a web site that deals with these type supplies? Kit or design/instructions available?

8. Could I buy one cheaper? Where?

Thanks for taking the time to read this long thread and all suggestions are welcome and needed.

Sincerely,

William (Billy)

[doorknob]

There have been a number of threads on cnczone.com discussing the Grizzly G8750 cross slide table.

In one of the more recent threads the OP embarked on a fairly extensive upgrade of the table, and IIRC his assessment of the unmodified table was that it was a good starting point which could be improved by adding better screws and bearings.

See http://www.cnczone.com/forums/bencht...oss_slide.html

I have one of those tables also, but I have been focused on other matters lately and so I have not yet done much with mine.

[UUU]

If you're using the drill press, then you'll need to look at the chuck. If it's held on a taper, most are, it's only suitable for drilling and is likely to come off in a dangerous way if used for milling. Its grip on the cutter is also unlikely to be good enough. Your up-down (z axis) drive may also have huge backlash in it - not so much of a problem if it's clamped up for each cut. The router approach sounds better, but I've no direct knowledge of these.