I'll just add briefly to the above. Foundational tools include a really good vise, an accurate drill chuck and a good tool holding system (R8 collets are okay; ER collets are more accurate, dampen vibration better).
Must have stuff:
- As stated, a good DTI. I would suggest a 0.0005" horizontal DTI. Spend some money on a decent one because you will use this a lot. The best ones are Swiss made - Interapid, Tesa, B&S, Compac. My personal choice is the Compac 214GA, a long range, large dial indicator. For the first time, Long Island Indicator Service is beating Amazon for pricing on this indicator. A very good option is the Interapid 312 as seen here. Go to Long Island Indicator Service's site and read up on these things before you spend money. I agree that a dial indicator is good to have but not essential for use on the mill.
- Indicator holder: many options here but they fall into three basic groups - the kind that is held in a drill chuck/collet, the kind that attaches with a mag base (like the Noga stands) and the kind that clamps onto the collar of the spindle (like the Indicol holder). I have all of these, including an Indicol with a Noga articulating arm, and the one I like the best because it is quick to use and very rigid is this one. Not for everyone at that price and you have to hold it in a chuck of some kind but it is very solid and versatile. I don't own this one but it looks pretty decent.
- Edge finder: Starrett makes a good one but the best deal I've ever seen is from Mitutoyo on Amazon; it works well.
- Parallels: You will need a 6" set. Most of us use the 1/8" thick sets and imports are usually okay. These things go up in size by 1/8" increments and that's mostly okay. However, there are times when increments of 1/16" is better and you will find that the ultra-thin sets are just the ticket. They also allow you to drill close to an edge and this is going to be useful one day, trust me.
- Work stop: This allows you to do multiples with one cutting set up. I cannot do without these things. I prefer the ones from Edge Technology and actually own three different models from them - talk about overkill. I would suggest this one at the very least. EDIT: make sure the thing will fit your T-slots.
- Fly cutter: you will use this to square almost every project cut from raw stock or billet. Many to choose from; ask the guys. I mostly use the Tormach Superfly.
- Drills: if you can, buy screw machine drills. They are shorter, stiffer and will help you drill more accurate holes. You will eventually need fractional, wire and letter size drills. You can buy sets, in that order, or you can buy a 115 piece set that includes them all. Consider metric drills, too. Good makers include Precision Twist Drill, Triumph, Dormer, Cleveland. Many others out there, too.
- Spotting drills: which one depends on what included angle is at the tip of your drills. For 118 degree drills, use a 120 degree spotting drill; for 135 degree drills, use a 140 degree spotter. I highly recommend cobalt spotters. Keo, Morse, Cleveland all make good ones.
- Small dead blow hammer: you will use this to nudge your vise into tram, tap down work pieces onto parallels, break a drawbar loose and threaten your neighbor who asks to borrow your tools. I use this one a lot.
Everything else comes after these things, at least in my opinion. There are tons of things to buy but my best advice is to make sure you need it and not just want it. Stuff like rotary tables are the darling of the hobby set but they will sit on the shelf for years between uses. Same for dividing heads and the like. Things you will eventually need include stuff like a good boring head, an angle block set or a tilting angle table, face/shell mills, slitting saws and so on.
Buy tools as the need arises but do your homework and buy good tools when you can. Take end mills for example. There are end mills with 2,3,4, 6 or more flutes that come in HSS, cobalt and carbide. Some have square corners and some are radiused at the edge. There are roughing end mills in both fine and coarse pitch and finishing end mills with geometry suitable for specific materials. Some are coated, others are not. You need to know what to use and when, then you need to learn how to use them.
You are going to hear that its okay to buy a cheap set of end mills from Harbor Freight and that's one way to go. I would suggest you learn the differences between end mills and then buy decent ones from Niagara Cutter, OSG, Melin, Brubaker, Regal Beloit, Morse, Cleveland, Ghuring. A good end mill cuts well out of the box and will last longer and cut more accurately and there will come a time when this matters to you.
I've gone on much longer than I intended but I really wanted to tell you that before you buy something, make sure you really need that thing. Every single experienced hobby machinist will tell you that there is a BIG difference between need and want; both cost you money but the former will get used and the latter often sits. Choose wisely.
