In order to build the steam engine I acquired a bunch of tooling.
- a few small tap and die sets. For each size I purchased taper, plug and bottom taps, two drills and the matching die.
- a teeny drill chuck with a knurled handwheel for hand feeding little drills. This has a half inch shank. Random amazon seller.
- 3" x 3" x 3" angle plate from littlemachineshop.com I machined some 3/8" tapped holes in this on one side to clamp the steam engine to and also machined the sides of the ends so I could indicate against them. With the engine chassis clamped I could work on the chassis casting on its side, at 45 degrees (in the vice) or vertical (hanging off the side of the table.)
- HFS (R) Type B V-Block & C Clamp Set (1-5/8"×1-1/4"×1-1/4") off Amazon. At least that's what I ordered. The ones I received are much bigger - 70mm x 45mm x 40mm approx. I'm not complaining. This came in handy for finishing off the eccentric.
- Springy tap drivers, two sizes. Not great quality, but they work. Amazon again.
- A couple of 12mm square by 200mm tool steel blanks. Amazon.
- 1/4" right and left tools and a couple of square blanks the same size. These were for getting into the crankpin machining. I was able to space them up to get to spindle height. Littlemachineshop.
- Right and left 1/2" lathe tools. These turned out not to work as it seems the tool height on the standard toolpost is metric so these sit 0.7mm high. Littlemachineshop.
To build this project I had to machine at all heights in my Z-space, with a bunch of different tooling lengths. This has always been a bugbear on this machine as the MT3 extension is extends the spindle more than the spindle has travel, so there are places I just couldn't get to in the past. With the tooling I have now this is less of a problem, though it results in a mixed bag of solutions.
- The standard MT3 3/8" mill holder covers a fairly wide range, and can get close to the table with the MT3 extension. Some extra range can be had by not using the flat when tightening up, and I have one long (1/4") cutter now as well.
- The MT3 ER32 collet chuck is a bit longer than the mill holder and allows a lot of flexibility on tool extension. In particular long drills can be clamped on the flutes to make them as short as needed.
- The teeny drill chuck can be held in the regular drill chuck for extra reach on small drills.
- I have a 5/8" MT3 collet. I made 1/2" and 3/8" aluminum collets sleeves to fit in it, allowing me to hold tools or the teeny drill chuck close to the head or on the end of the MT3 extension.
While the randomness of this is a bit annoying it is no longer blocking. I don't have to dismount the work and space it up just because I'm changing from a mill cutter to drill like I used to some of the time.
One major annoyance was the lathe toolpost and tooling. I essentially have only one lathe tool that works - a 12mm 60 degree threading bit. It's the only one that gets to the correct spindle height on the standard turret toolpost. The Shoptask "quick change" toolpost is a bad design. While it is adjustable, it's hard to do, and quick change it is not. Worst: the tool holders are narrower than the tool post, so the toolpost gets in the way. Don't get me started on the "compound". Which is why I've ordered a Multifix 'A' toolpost from PeweTools in Deutschland. With a bit of luck it will be here by Weihnachten. That's the topic for the next sub-project.
While using the DRO on a real project for the first time with many hours of use I find that I almost never look at the handwheels anymore - or worry about backlash much. I'm habitually locking the unmoving axes. This is removing my concern about retaining inch leadscrews which opens up the option of cheap metric ballscrews when I get to the CNC stage. Prices for these are now under $100 per axis. While CNC with DRO position for feedback should care less about backlash than a "blind" setup, backlash should still be minimized. At his point it is up to 75 thou on the Y axis as apparently the set-screw on the acme nut has loosened again.
Another concern for the lathe is the distance from the center of the toolpost to the edge of the table. If the swing of the work (and chuck jaws) hits 200mm, something would always hit the table if I got in too close. Now that the DRO scale is on the chuck side, this issue issue is even worse. I ran into this cleaning up the steam engine flywheel (over 6") in the 6" 4-jaw chuck. I ended up using the 200mm tool blanks extended way out to get it done. Not very rigid. A partial solution would be a smaller 4-jaw chuck. Like a 5" or 130mm like the 3-jaw. Another solution would be to make a toolpost support block that extends forward - somewhat like a traditional compound extends the toolpost out on a normal lathe. When I do the ballscrew conversion I think I'll spin the table round so the gibs are towards the lathe chuck and the DRO is safely on the other side. In the meantime if I do need to do big things I can use a beefy boring bar tool on the Multifix to reach out over the divide.