Newbie question on converting drill press to mill

Hi. I am a hobbyist looking to learn basic machining to use in welding and fabrication. I know I am going to be flamed for my question, but bear with me because I am severely cost constrained and let’s be honest- probably everyone on this forum simply likes making their own tools.

I am converting a 1937 craftsman drill press into an end mill. It is in spectacular condition. I am replacing the bearings with tapered bearings to properly accommodate the lateral milling forces. Since this tool is so old it is solid as hell but am going to add a bit of external bracing to make it even more solid. My question is this: the spindle is solid rod. I want to install a collet system but since I can’t insert anything inside the spindle I must use some type of externally mounted system. At least for now, I don’t want to completely change the spindle and quill because that may not be workable with the existing original 1937 cast iron housing/frame which I need to keep for cost reasons (and I just plain love the way it looks). Any thoughts or suggestions from you pros?

I don’t need high precision or high speeds. I will address work piece holders as well but that is an easier thing to take care of than the tool holder issue. I look forward to hearing your ideas. Thanks.

Buy a milling machine

If I was able to spend the money I would. However the drill press was free and the bearings cost about $60 for a set of 4. I still have to buy tooling, tool holders and work holder/table. Like I said, I am severely cost constrained so buying a mill is simply not within my means. I’m hoping someone will look beyond that and offer some workable suggestions for my situation.

My initial reaction to your post was sympathy. When I was thirteen or so, I was exposed to a real lathe, an ancient Carrol-Jamison, and began to make things. I had never seen a milling machine, but eyed the drill press and visualized a cross slide to be able to make flat cuts on metal. I fortunately did not attempt to use the drill press, as I gained access to a more satisfactory machine.

there are so many reasons that a drill press can not be a satisfactory milling machine that I will not attempt to discuss them. My advice is for you to save your funds and time, and buy a machine intended for milling. Avoid the cheap Chinese junk and look for some good old iron.

I am a bit of a newbie also. I am replying because a doubt you will get much useful input from experts. With good reason, because what you want to do lilely with end up with disappointing results.
If you want to will plastic, or maybe very light cuts in aluminum (and don't care about accuracy), maybe you could have some success.
I would not bother with a collet. First I guess I would see how much runout there is using the chuck. That is not likely to work out well. Depending on whether the chuck is threaded or has a taper, you could make an adapter for one size of end mill shaft and hold it will a couple set screws (grind flats on the shaft).
If you can scrape up some money there are some deals out there on small horizontal mills or even shapers. That would be a far better option.

Lmheim said:

Hi. I am a hobbyist looking to learn basic machining to use in welding and fabrication. I know I am going to be flamed for my question, but bear with me because I am severely cost constrained and let’s be honest- probably everyone on this forum simply likes making their own tools.

I am converting a 1937 craftsman drill press into an end mill. It is in spectacular condition. I am replacing the bearings with tapered bearings to properly accommodate the lateral milling forces. Since this tool is so old it is solid as hell but am going to add a bit of external bracing to make it even more solid. My question is this: the spindle is solid rod. I want to install a collet system but since I can’t insert anything inside the spindle I must use some type of externally mounted system. At least for now, I don’t want to completely change the spindle and quill because that may not be workable with the existing original 1937 cast iron housing/frame which I need to keep for cost reasons (and I just plain love the way it looks). Any thoughts or suggestions from you pros?

I don’t need high precision or high speeds. I will address work piece holders as well but that is an easier thing to take care of than the tool holder issue. I look forward to hearing your ideas. Thanks.

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If it is in spectacular condition, sell it and use the money to go towards a mill. Collectors like that drill press especially if in nice shape. The original chuck if present used a taper with locking collar which is pretty sturdy, but the rest of that drill press is a bit weak. Especially the design of the spindle pulley interface is lousy. I swear the engineers at Atlas never heard of Eli Whitney or tolerances having worked on several drill presses in that series.
If you want to still persue this, I suggest you look at some of the home machinist sites. Craftsman and Atlas brands are not allowed to be discussed on this site per the FAQ.

Around 1952, I was in a friend's basement. His father was an engineer and made drawing pencil lead pointers to sell. They were just a block of wood with a vee cut and sandpaper glued in the vee, He had a drill press and what I later learned from the Sears tool catalog was a (Palmgren) x-y and rotary table. The x-y table made the drill press look like a milling machine, though I had no idea what a milling machine was in 1952. That Sears catalog also had a collet chuck for mounting router bits in place of the keyed drill chuck. That feature was possible because the drill press (and some Delta/Rockwell models) had a 33 Jacobs taper spindle with a locking collar. The locking collar made it possible to remove and install a number of different tools on the spindle. Normally, a 33 Jacobs taper gets the chuck mounted once and the chuck will never again come off, even if you want it to. Unless you try to mill steel with it; then the chuck will fly off under the influence of heavy side loading. The Jacobs taper is only meant for axial loads, as you get when drilling holes. The locking collar prevents the tooling from flying off under side loading, but it still does not make a drill into a mill.

In 1962, I went to an estate auction and got a floor drill press with x-y rotary table and the variable speed attachment that looked like it had never been used. I bought the collet chuck and drum sander and other stuff for it and soon proved that it was not a milling machine. I did do a sort of surface grinding job on it once, but that was not really a good job.

I bought my first real milling machine in 1964 for $139 (new) plus a bunch more for tooling. It was very small, of course, but made in Austria and quite capable for tiny work. In those days, I simulated milling on larger parts with a 6 x 48 belt sander and files.

It was 1974 when I bought a new Rockwell vertical mill, which I still have. It is a great machine, not much smaller than a Bridgeport, but a lot easier to move.

We all got started doing things cheap or doing without. It is a learning experience that can be valuable. Milling on a drill is educational if nothing else.

I will add that woodworking routers, especially the ones with 1/2" collet capacity, are more capable of milling metal than a drill press spindle. They run at speeds suited to milling brass and aluminum. They have powerful motors and capable bearings. Most can be slowed down enough to run carbide tools in steel or cast iron. I had a very difficult access job a few years ago, mounting a DRO on a lathe. My solution involved using a 1/4" router with a carbide rotary file to flatten a portion of the lathe's cast iron carriage. Worked great.

Larry

Normally I would say "stay away from cheap Chinese machinery". However in your case and with your budget, I would have to say that even a cheap Chinese mill would be better then converting a drill press. As stated, there are many reasons not to do it. Now I must say that I have seen some third world machining done on nothing less then what you are attempting. And you are probably starting off with a better piece of iron then what they had. You did not mention what you are going to try to mill. That is really the key here. Anything more then non ferrous material is going to be a real problem with some kind of homemade end mill holder sticking way out the bottom of the spindle. You could probably mill 1/4" AL and get away with it since you mentioned you are not looking for precision or speed. If this is truly the case then I would stick with a side grinder, some cape chisels and a good set of files.

Lmheim said:

If I was able to spend the money I would. However the drill press was free and the bearings cost about $60 for a set of 4. I still have to buy tooling, tool holders and work holder/table. Like I said, I am severely cost constrained so buying a mill is simply not within my means. I’m hoping someone will look beyond that and offer some workable suggestions for my situation.

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...and they will...over at hobby-machinist.com
Please go there with this question

Very bad idea.

To OP: you think that starting with a drill press gets you part of the way to having a milling machine. You are wrong, the drill press sets you BACK from having a milling machine. There are many many many issues you will need to solve from scratch that will be impossible to get right, you are essentially trying to build a milling machine from scratch. You'll need billions of dollars and thousands of engineers to get this right.

On the other hand, there are THOUSANDS of almost for free milling machines sitting around ready for you to use. Spend your time finding a workable milling machine rather than trying to re-invent the wheel with the WRONG starting point. You will be 1000000x times better off spending your time working to save some money to buy a milling machine from craigslist, ebay, etc than trying to adapt your drill press.

crossthread said:

Normally I would say "stay away from cheap Chinese machinery". However in your case and with your budget, I would have to say that even a cheap Chinese mill would be better then converting a drill press. As stated, there are many reasons not to do it. Now I must say that I have seen some third world machining done on nothing less then what you are attempting. And you are probably starting off with a better piece of iron then what they had. You did not mention what you are going to try to mill. That is really the key here. Anything more then non ferrous material is going to be a real problem with some kind of homemade end mill holder sticking way out the bottom of the spindle. You could probably mill 1/4" AL and get away with it since you mentioned you are not looking for precision or speed. If this is truly the case then I would stick with a side grinder, some cape chisels and a good set of files.

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I've had cutters thrown across the room with only the slightest sideways pressure on a drill press cutting WOOD. Drill presses are not designed for sideways pressures, the cutters and chucks tend to FALL out of the machine. Drill presses are designed for downward pressure only. Thus, the OP should track down a milling machine and give up on the drill press.

You will be 1000000x times better off spending your time working to save some money to buy a milling machine from craigslist, ebay, etc than trying to adapt your drill press.

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Kind of like the car thing. How much money do you pour into your Honda Civic
to make it go faster? By the time it gets faster, you could have just gone
out and bought a Camaro, been faster, and saved a bunch of money.

I would keep your drill press as a drill press, sell it if its worth selling,
and save the coin to get a real milling machine. In the long run, you will
be a lot more productive and a lot happier, and you'll probably have
more money in your wallet too.


I'm all for using tools in unconventional ways, and I'm all for modifying tools
to do what you need them to, but there is a point where you are better off
buying the correct tool to begin with.

I'm also all for building stuff just for the sake of it. BUT if you HAVE
a milling machine you can then build all kinds of other cool things.

Your idea is not new, it has probably been tried a million times. I did this in the late 80's with an Enco drill press and x-y table, worked ok for plastic and aluminum, it sucked massively on steel. If all you want to do is work on small plastic/aluminum/maybe brass parts, it may work in a half-assed way. If you want a real milling machine, go poke around the local shops and see if they have something shoved off in a corner collecting dust, or start auction shopping.

I've been in your shoes and sympathize.

The main problem with a conversion like that is that the drill chuck is, typically, held on by a taper. Intended to be used with forces parallel to the spindle, as in, straight down, drilling only. The problem with milling sideways is that the forces are well, sideways and the chuck typically falls off the spindle. Usually plays hell with the work or the tool, or both. :-)

If you can figure out a way to bypass the taper connection, you may have something that works for you. An xy table is a good addition, for sure.

A member here recently picked up a J-head bridgeport for $50. It was a cherry deal for sure, but the point is to keep looking for a real mill.

Sent via CNC 88HS

Cole2534 said:

A member here recently picked up a J-head bridgeport for $50. It was a cherry deal for sure, but the point is to keep looking for a real mill.

Sent via CNC 88HS

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Yahbut... Bridgeport did the same thing he is trying to do!

Started out with a cheap drillpress, Morse Taper 2, didn't even have an ass to call its own, hadda be hung ONTO a proper host as an accessory.

Kept adding Iron all AROUND it until it began acting like a mill. On good day, anyway. If yah didn't PUSH it.

1,500 lbs oughta do it?

But you still won't get the silly head to cease flexing.

Find an old line-shaft horizontal in a barn free for the hauling, OTOH, skip the pain, become a "mill hand".

"Get your head around it" (literally). Then yah will know what yah best do NEXT!

Because one may start there.. but yah don't exactly want to stop there, do yah?

I sympathise with the lack of money, been there myself.

I've also tried what you're proposing. Unless it's an *exceptional* drill press on the lines of an Arboga, you're doomed to disappointment, broken tooling, absolute shit to nonexistent tolerances and if you're not careful with PPE, injury from broken bits.

Think I'm exaggerating? I'm not.

My advice like everyone else here is - don't do it.

If you insist on doing it, go somewhere else and ask about it. I don't think anyone here is going to critique your plan and offer help.

PDW

If you want a drill press buy a Bridgeport, if you want a mill.......

If you can't afford a mill that works then how can you afford to invest money into something that won't work? It's an honest question, think about it.

Hardplates said:

If you want a drill press buy a Bridgeport, if you want a mill.......

If you can't afford a mill that works then how can you afford to invest money into something that won't work? It's an honest question, think about it.

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OP want's to make "gun parts" and so needs a "Mill"......