Drilling machine as a milling one

Well, you'll get AWFUL accuracy, unless you get one beefy X-Y table, and your spindle is nearly perfect.

LLoyd

Right on, Lloyd! Other RCM posts over the years have resoundingly recommended against doing this. Most of us have tried it; it can be done; it is inherently dangerous; it is only suitable for very light milling; it is a good way to become adquainted with the ballistic qualities of your flying spindle. Get a good table, but use it for accurate hole location, not milling.

My drill press has a tapered spindle holder, which instantly releases the hold once sideways force is applied.

My mill had a tapered spindle, and does NOT release the collet when side pressure is applied. Well... there is this thing about the drawbar...

LLoyd

Thanks you for all these tips I see what you want to say when you talk about danger I will take many precautions with my drill I will use it only for very light work and I will avoid too large tools

haha... that's how my 8530 mill was made... spindle with an allthread bar.

if your drill press, like mine, holds the chuck by means of a taper, forget about it, it will not work at all. Do not even bother trying.

I want to remove the chuck with its MT2-B16 adaptation and buy some milling tool holder in MT2 directly in the spindle (or quill?)

That's OK, you'll get it anyhow.

Jim

It will work pretty well, right up until the chuck and cutter come spinning out of the spindle like a carnivorous top! Pretty exciting stuff, keep the first aid it handy.

Up until that time, it will be a little sloppy because the spindle bearings are set up for vertical load, not side load. Expect the tolerance to suffer as it would wear quickly if loaded beyond what the designer expected. Also, many of the X-Y tables are poorly made and will add to the inaccuracy. Now, if you happen to have a big old American DP with a drawbar holding the arbor in place, and a massive bearing structure, you might be fine. Some of those are made stouter than many small HSM mills.

Somewhere there's a website showing conversion of a small Chinese DP into a CNC milling machine. It includes a minor redesign of the spindle.

Rex

My machine shop instructor from twenty years ago always said, "You can drill with a mill, but you can't mill with a drill"

Drills don't have bearings for side loads even if you fix the taper and mounting problems.

Karl

I'm sure this has already been said (but I'm too lazy to read all the posts)

The spindle ona drilling machine is generally not accurate or beefy enough to handle side loads. Plus, the bearings inside the drill press or machine are sometimes not made for side loads at all. You may have problems.

For the same price/effort as adding that table, you might be able to pick up a Jet Mill/Drill or used Bridgeport, etc.

Regards, Joe Agro, Jr. (800) 871-5022

Yes, and some drill presses have a threaded collar assembly that holds the tapers together ... that's better, but still not really adequate for milling.

Yes, some light milling can be done in a drill press, if it HAS to de done that way, AND the proper precautions are taken, and perhaps several modifications made to the machine, and you're lucky, but it's still a BAD idea.

Save up and get a decent small used milling machine. You can get NEW milling machines from Harbor Freight for a few hundred dollars. They're certainly NOT great, but far better than a drill press.

Dan Mitchell ============

But you'll still need a drawbar INSIDE your spindle to hold the milling adapter in the spindle. A very few drill presses have such a drawbar. The vast majority do NOT! Without a positive locking device (like a drawbar) to hold the chuck/adapter/cutter in the spindle you are asking for BIG trouble!

You MAY get away with it, some do, but it's always a BAD idea!

Dan Mitchell ============

Gil,

Drill press quills aren't designed for a side load. Neither are the castings, although some older drill press castings are very heavy. Milling machine spindles have double bearings on the spindle end.

Also, the attacments (various types) of the chuck to the spindle is designed for axial forces only. If yours uses a taper, wear your running shoes. The chuck and tool will be chasing you around the shop when it pops out.

Mark

For me, the chuck simply gently fell out of the drill press as soon as side load was applied. No injuries. I was not trying to mill anything, simply tried to drill into an existing hole not at center, sloppily.

That quickly made it clear that milling with a drill press like mine cannot be done.

"Gil HASH" wrote in message news:42f8dea5$0$25042$ snipped-for-privacy@news.wanadoo.fr...

Subsequent posts concerning this most frequently asked of all frequently asked questions have given all the right reasons for not doing this and for why it won't work well at all. Now for some situations in which you might get away with it.

Very light, very small milling in soft materials such as plastics, or wood. Brass is pushing your luck. Steel is hairy at best. Wood is problematic because you won't be able to get the spindle speed high enough. And if its wood you're doing, consider some drum sanders on your drill press as an alternative. You'll need very sharp milling cutters (e.g., end mills) because you'll need all the help you can get. Also, if your X-Y table doesn't have gib pressure adjustments, forget the whole thing. You'll have to make it really tight -- just to the point where you almost can't turn the feeds. Let's say you want to cut a slot or a pocket in a piece of material. Do most of your metal removal by drilling down, rather than by putting side forces on the end mill. This helps to avoid the almost inevitable popping out of the chuck. Once you've gotten most of the material out, then you can apply light side forces to mill in the conventional way for a cleanup. By and large, this is a desperation practice, only to be done when there is no alternative. Rather than buy a mill as most people suggested, I'd buy a lathe and get a milling attachment for it. That's a whole lot better than milling on a drill press. I've done it for plexiglass when I had no other way -- but it was tricky and accuracy was barely acceptable. I once milled steel on my drill press and it's not an operation I'd care to repeat. My (very old) mill's motor had died and I had to machine an adapter rig for a new motor. It was too big to do on the lathe -- hence doing it on the mill. It entailed a lot of chain drilling, hacksaw work and lots of care prior to milling things workably clean. Once that was done, I mounted the new motor and promptly machined a new, proper, adapter.

The big decision, however, when it comes to milling on a drill press is how high you intend to have the table when you will. Up high, you are putting faces, chests and hearts in harms way.. low down, other parts come into the picture. You pays your money and you takes yer choice.

Boris

I tried holding an end mill in the drill chuck of a mill drill once to plunge-cut a small slot in some plastic. Even with vertical feed the unbalanced sideways cutting force loosened the chuck.

jw

Fast way to "mill". And the bonus is, you'll get the inaccuracy you expected, plus some thousandths. Or tenths.

~Dave, metal hacko