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View Full Version : Milling on a Drill Press? Eh, ok...



BadDog
09-19-2007, 04:33 AM
Yeah, I know. You don't mill on a drill press for many very good and valid reasons. Some do anyway, some tear stuff up, some get away with it. Some drill presses like the Arboga(?) have some limited measure of ability, and then there is the whole category of "drill/mill" machines...

But I downloaded a manual for my 20" Wilton VSG. There is a whole section on using it for light milling :eek: , including both aluminum and steel among other materials. Now, this thing does have a massive (for a drill press) 3" quil with enormous bearings, but no provision for a draw bar due to the big gear reduction head. I suppose it's at least as big and rigid as the RF round column mill/drills, but with no draw bar, I wouldn't be too keen on it. Still, nice to know the manuf thought it worthy enough of such tasks to cover it in the manual.

I've heard of folks doing it, but never heard of a strictly "drill press" model where the manufacturer included milling info in the manual. :confused:

Evan
09-19-2007, 09:04 AM
My Strands has basically the same head as an Arboga, made by the same people and it works ok as a mill. Of course it's a pain as it can't hold any sort of setup since everything is free to move. It does work though.

http://vts.bc.ca/pics/mill0.jpg

http://vts.bc.ca/pics/mill1.jpg

J Tiers
09-19-2007, 09:38 AM
The "no draw bar" part is a nuisance to some degree....

BUT, if you look at older books on mills and milling, you will see pictures of old-style end mills.......

Yep, tanged tapers, and no provision for any sort of drawbar. Now this was probably mostly for horizontal mills. And rigid ones, at that. But evidently it was not thought at that time that a taper had to come flying out at the least touch.

Probably the very rigid machines have something to do with it, that tends to cut the vibration, which is what loosens the taper. But a good-fitting taper is tight and should not come rattling out.

Watchmaker's lathes and even mills have no drawbar for cutters, the taper is the only thing that holds in the tool. Even high quality german machines, such as one that was featured in a video attached to it's ebay ad a while back (linked here maybe?). That I noticed used taper mount cutters, and apparently had NO drawbar.

All that said, in a drill press, milling can be iffy. Much more so if no means for holding in the cutter.

In that case, the integral-taper cutters might be better, less length, and so less leverage trying to loosen them

Evan
09-19-2007, 09:45 AM
I modified the spindle to hold the cutters with a collet.

http://vts.bc.ca/pics/hold1.jpg

http://vts.bc.ca/pics/hold2.jpg

Steve Steven
09-19-2007, 12:18 PM
I tried to mill with my Tiawan drill press (bench type 16 speed, 30 years old now and very loose) and drilled and tapped the morse taper shank for two #10-32 socket head cap screws that fit into the knockout at the tang, so the socket head prevented the shank from dropping out. Got a tight fit by turning off a small ammount of the socket head till it fit.

Didn't work too well, that was 10 years ago. Shank would still loosen up. Ended up getting a old (1937 mfg) Van Norman #12.

Steve

Marc M
09-19-2007, 03:18 PM
Dog, it really depends on the machine. Your Wilton, Evan's Strands, my Solberga, Arboga's, etc. are all well built, heavy duty industrial machines. They have pretty massive bearings on both the bottom of the quill and the top, and are rigid, heavy machines. Doing light milling on these machines is not going to be much of an issue.

On the other hand, the typical consumer drill press is far too light and flexible for it. The less expensive ones don't even have a bearing at the top of the quill. Putting a lateral load on these machines is a bad idea. I know some folks do it and say they haven't had a problem, but that doesn't make it a good idea.

Evan, that's an elegant solution to the drawbar problem. Very nicely done!

Marc -

gmatov
09-20-2007, 03:18 AM
If you MUST use the DP as a mill, why don't you just cut a MT drift to the right length and drive it home? Keys are cheap.

Always drive it back out from the opposite side..

I know MT2 can work loose, not if they are secured.

Cheers,

George

BadDog
09-20-2007, 05:31 AM
I'm not sure exactly what you are getting at, but if your talking to me, I'm the last person to suggest using a drill press as a mill. :eek: I was only commenting on my surprise at the *manufacturer* specifically covering use of a drill press as a mill. I would NEVER have expected to see such a thing. There were no warnings of dire consequences, or voided warranties, or any sort of hedge. Just a "if you want to use it as a mill, here is what you can do" kinda thing. To me, that said they MUST have built that drill press VERY well and were confident it could handle such a task without damage or serious problem.

All that said, I don't think this will help the folks most often insisting on (or at least asking about about monthly) milling with a drill press. I got mine cheaper than most light mills, or even import Mill/Drill machines. But the typical market value on these things makes a HF mill/drill (which would be better for milling simply due to the draw bar) a cheaper alternative. So it's not likely to appeal to them in any way. Rather, they would be better off getting the HF Mill/Drill and doing light milling while having a pretty kick-but drill press in the bargain.

One of the main reasons I wanted a drill press like this (actually, never figured on one THIS big) was to avoid the torque limited back gear of the Bridgeport. That and it gives 7" of quil travel, plus the ability to seat taper drills.

J Tiers
09-20-2007, 09:26 AM
Seven inches+ quill travel? That's nice. I thought 6 1/4 was plenty, but I have already run out of travel a few times.

As for milling.....

The main issue I found when I, like everyone else, tried that once, was that the sloppiness of the quill and spindle allowed the cutter to wander too much. The slot I cut was not close to straight

Now, this was with a cheaper chinese unit, with one bearing, (didn't know that then), but I was "milling" a slot in WOOD. Cured me of the thought.

Aside from the quill/spindle problem, I would not think that the general 'flex" would be much more than milling with a typical palmgren adapter in a bench lathe. (If you have an old Springfield, just keep quiet, I know about them).

chief
09-20-2007, 09:36 AM
I used to take large (1" and up) endmills with chipped teeth, grind a chamfer on them and them use them to bore bolt hole flanges in valve bodies using a radial dress.

Evan
09-20-2007, 09:49 AM
Good point Chief. Center cutting end mills do an excellent job of drilling large diameter holes in thin stock like sheet metal. Good way to make holes in project panels. If the stock is really thin clamp it on top with a thick cover piece that already has a hole slightly larger than the hole to be drilled and drill through that. It's even possible to drill large clean holes in thin brass shim stock this way.

BadDog
09-20-2007, 03:12 PM
Oooh, I like that...