Milling on a lathe

I was looking into surfacing the side of the bigger HF cross slide vice and mounting that to the compound mount.
 
Sounds great @mikey. You have my address, let me know when to expect them. :D

That's the long term plan, but it will be a while before new machines get added.
 
Once upon a time I tried that on my SB9. I made a 1/2” x 4” angle iron 4”long,secured to T slot on compound! I cut holes in the vertical face of the angle iron and a few slots also for mounting and adjusting items to be milled. You can get creative with this keeping it close to centerline of compound making movable horizontal jaws to hold the work using the holes and slots to fit the workpiece. On top jaw drill and tap 2 or 3 vertical holes and tap fine thread for holding screws, like the ones on tool holders that you can tighten your workpiece with ! As far as holding the end mill, measure the horizontal length of the part of the jaws that will extend below the diameter of chuck hole! Take the depth length from back of jaws inside chuck hole to end where diameter narrows and mark the length on end of round stock continuing with horizontal chuck jaw length marking this additional length on stock. Now you have 2 consecutive marks, chuck unmarked end of stock and turn hole depth part to diameter of hole, tight fit. Next turn the horizontal chuck jaw length approximately .250” deeper than first cut (chuck hole diameter). Now you have 3 diameters on stock, turn stock around and mount into chuck and tighten. It should fit nice and tight, you might have to tweek a little. You now have a thicker stub outside the chuck which can’t pull out or push inward. , leave it about 2” sticking out. Put drill chuck in tail stock. Choose your shank size for endmill according to what your lathe size can handle. Buy a Weldon shank, centercutting endmill with flat ground on shank of size you decided. Place endmill on top of stub extending from chuck parellel and horizontal with Weldon flat visible. Measure from center of flat to shank end of endmill, double measurement and mark stub from the end including center of flat from end of stub . Mount endmill into tailstock drill chuck real tight,bring it to stub end and slowly use endmill to drill shank hole to depth of mark on stub make it exact ,you have to peck drill this hole to relieve chip buildups. Get a set screw and drill and tap mark for center flat. Put endmill into hole,line flat with setscrew and tighten! Here is your endmill holder! I know this was long winded but once you understand it,you’ll make it in a few hours! I’ve made quite a few. Your lathe is limited, save for the biggest milling machine you can fit in your shop! Good luck.
 
So I've been tossing options around and think I have most things ready to mess with. I ran into a question I thought would be good here.

Many people use mills for drilling. Many are advertised as drill/mills, the smaller ones anyway. If I wanted to drill in this setup, perhaps on a flat workpiece, could I use my tailstock drill chuck in the headstock with the proper MT5/3 adapter? I know end mills need to be positively held with a drawbar in that configuration. Do drills? I've never seen people mention it, but that might be because it's too nutty for most people to think about in the first place.

This is partly because my drill press has so much flex that I almost need more travel than my 1" indicators have to measure it. :) But mostly because now that I thought of it I almost have to try it, if only to see that I hate it. But I want to make sure I'm not likely to break equipment or people doing it. And yes, I'm planning to get a decent drill press or mill or both.

A drawbar isn't so essential for drilling, milling yes because of the risk of and endmill pulling the chuck from the taper, but the pressure from drilling should keep it seated and there isn't the cyclic side-load that tends to work tapers loose when milling so you should be good to go with a taper-shank drill or a drill chuck in the spindle taper.
In a pinch I've drilled from the headstock, and then offset a boring bar in a 4-jaw chuck for a more precisely round hole - that's a hassle to adjust, trial bore and careful measurement followed by adjusting the 4-jaw with a dial indicator against the tool - a reamer the right size would have been a lot easier and way, way quicker! Anyone have a 30.05mm reamer handy?
One thing I found handy was when drilling a row of holes at precise spacing: drill the first then loosen the vice/clamping, leave the drilll in the hole and wind the cross-slide out (and in to take up backlash) clamp up and then retract from the drill, advance cross-slide by the hole spacing and repeat. Something I couldn't do on my cheap Chinese baby drill-press, particularly with the 7x3 channel I wanted accurate holes in (still haven't finished that press frame!)

Dave H. (the other one)
 
So, I got some work done on it over the weekend. Drilled and countersunk the holes to hold down the adapter plate and the mill adapter. Found the T-nuts a bit tall, ground them down. Then discovered that I need longer screws for the milling adapter. So I'll pick those up today. I also discovered I really need some nicer countersinks. These chatter too much. And that my drill press is worse than I thought, the pulley set screw appears to be stripped out, so the motor pulley jumps around and makes a ton of noise. Doesn't have much torque either, as one might expect with the pulley loose. It doesn't help that the operator also has more than one screw loose. :)

In the mean time, I figured I'd look at the end mill adapter I ordered. MT5 and end mill side look fine. But the box it came in and the website said the draw bar is 1"-8 thread. Hmm... ok, seems like overkill, but I've seen that size all-thread locally. Go to get some, just to find out they have it, and washers, but no nuts that size. So... why stock the stuff if you can't connect it to anything? pffttt.. Whatever. It was overpriced anyway. I have a lathe, so I instead start getting stock out etc to cut some threads. Only then do I look closer and realize, that's not a 1" hole. No way.

Turns out, it's a 5/8 and I didn't discover it until after all the stores were closed on Sunday night. facepalm. That's what I get for trusting the spec. Not that I could have actually done anything with it, but still felt like a kick in the junk. Hope you all had more success with your projects! :D
 
Well, I got it mounted up. I think it might be the most accurate pattern drilling I've managed at home, but I'm not happy with it.

The bolts to hold the plate to the cross slide are off just enough that getting the last bolt in isn't happening. Combined error is just too much. Well, 3 isn't horrible and it's stable, so figured I'd mount up the milling adapter. Those holes ended up working well and all 4 are installed. Feels solid, but I can tell it's not quite square. Indicator tells me that it's off about 0.03 over 3". Pfftt. I think slots and things where depth isn't crucial could be done. Perhaps shiming the table between the vise/work could be good enough. I know this type of set up is never going to be super accurate.
 
Would love to see some pictures ttabbal.
This is how I managed to do some accurate pattern drilling on my lathe,

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I did forget to post pictures. :)

I also realized that I didn't indicate the vertical, it's under 0.001 over the entire movement range. So that's good at least.

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Just for fun, here's my drill press... It's, um, not so good. I know what they say about a craftsman blaming his tools, but I think an exception can be made for this thing. :D I'm willing to take more than half of the blame though.

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