O-ring tool - for Ian

[KeithB]

Ian, that is a most impressive piece of work! And doing internal threads first, wow. I can well appreciate the time and patience it took.

I've made spiders for both our lathes. I've also made some bushings with an OD that fits closely inside the spider and has a central hole the proper diameter for the common sizes of bar stock we use. Clamp the bushing in place with your setscrews, that way you don't have to clamp on the piece itself. You may not use any size stock repetitively so it might not be worth your time and trouble but if you did find that you were making a lot of stuff from say 3/8" rod stock you might want to consider it.

Love the idea of a handwheel to be able to turn the spindle by hand, it's practical on a smaller machine.

 

[Ian]

Since you sent me that piece of rod that was bigger than the one I was going to use, I went ahead and bored the end out to just over 26mm (thread major plus a tick) which gives me room to use split bushings under the clamping screws even when running parts that are near max spindle bore diameter. Since I made this spider primarily for supporting finished rifle barrels, making bushings of some sort made sense vs. putting the clamping bolt button tips directly on the blued steel.

The hand wheel was an idea I had mid-stream, mainly with 4-jaw chuck adjustments in mind. This little lathe is, well, SMALL, and my hands are large, so there's not much room to reach around indicator fixtures or the carriage to grab the chuck and rotate it when indicating center on a part or rolling the chuck to the one small window where I can thread the key through everything. Also, the chuck is small and spindle/drive fairly stiff to turn by hand so unless I have room to wrap my hand around it it's actually pretty difficult and awkward to turn manually. Having the ability to just reach over to the left a comfortable distance and get a good grip on the hand wheel to index the spindle as required is a huge bonus.


Freebullet, I did a lot of research before buying this one and still think it was a good choice. The large size of the steady rest, long tailstock quill travel, and long compound travel compared to the next two larger machines factored heavily into my decision and I'm glad I didn't go for the 9x19 or 8x16, even though those machines each have a few enticing features of their own (one has quick-change gears for the cutting speeds and only two change gears for threading, and one has a 1" spindle bore, not to mention the longer beds). I think the lathes like mine are the basis for the mill combo, but I wouldn't get one of those because there's just no room to work or put measuring tools on the lathe as it is and a mill setup would make the cramped space so much worse.

 

[KeithB]

No advice intended here, just the comment that most of the people I've talked to and read about complain of two things with the little combo machines:

1. Lack of rigidity.

2. They're always set up to do the wrong thing.

Have also heard the same #2 point from owners of Shopsmith(?) type universal woodworking tools.

 

[freebullet]

Did you see that part you made, yeah it was a great purchase! Those gears must not be under incredible stress like I'd thought. I was just a bit flabbergasted by that, it's not really even a negative so long as they work like they should.

Yes, I've read the same about the combos. Almost think I'd get more use from a mill first if bought separate. I'll need to learn more first anyway, please do feel free to advise. Sorry for the inadvertent hijack

 

[Ian]

The plastic change gears and tumbler gears for the leadscrew drive aren't under much stress. The plastic reduction and drive gears for the spindle are only under as much stress as the operator dictates, and I think this is where the big difference between the capabilities of a mini machine vs. a full-size engine lathe comes out. It's not that the minis can't do tough work within their size limitations, it's that they lack the power, mass, and rigidity to do heavy work FAST.

The hobby aftermarket offers cast gears (Zamak probably) which are not any stronger, require lubrication, and are noisy. I'll stick with plastic for now, especially since repair parts are plentiful for these machines.

 

[KeithB]

One way to reduce vibration on smaller machines is to use at least one plastic gear in the gear train. Having all the gears be plastic isn't a bad thing at all. Cheaper than cut metal gears, zero backlash, self lubricating, quiet... what's not to like? If you ever strip the teeth off one of the gears it's failure probably protected something else in the drive train.

Ian's right, it's not that you can't do good work on a small machine, you just need patience when you do it.

A good friend of mine runs a very successful machine shop and he won't buy a Haas CNC lathe. I love mine. Why? He does not consider them to be heavy and rigid enough. I paid about $35k for my Haas. He paid more than $200k for his last lathe. (It will handle approximately the same size work.) He can take off the same depth of cut in one pass as I can safely take off in 2-3 passes, and at a higher feed rate. (He also charges more per hour for work than I do, it all comes out about the same cost in the end but he gets 2-3 times as much work out the door every week.)

It's all relative - pay more, do more quicker. But ultimately it comes down to the skill of the operator. I predict that Ian will do some very interesting things with his mini lathe.

 

[Ian]

This is the stuff you have to learn by doing, likely because starting out from scratch with no education or experience if you're like me you don't even know what questions to ask about what to buy. I was originally under the impression that the principle limitation of small machines was obvious: SIZE. Well, how often does a machinist use all four feet of the bed on his engine lathe? Not often, probably. A person on a lathe forum who was looking for mini lathe recommendations (hobbiest) stated he didn't NEED a 1000-lb machine with the size capability everyone was telling him he needed, because he only wanted to do small work. One person simply said about not needing a half-ton of iron: "YES YOU DO". Well, he made a good point. Yes you do, really, even for small work. But you can make do without, like me, just use sharp tools and take your time.

 

[Pistolero]

I remember when you were doing some pretty darned good work with files, drill press and cold chisel (exaggeration ), and
several of us kept saying "You really need to get a lathe."

Now you can see what we were thinking. You were already doing so much with so little... now you can do a lot
more, with a lot more. I commented bck when you were still looking that the plastic gears would be fine, and as Kieth already
said, they are self lubricating and plenty strong enough to drive the feed system. My old Sheldon has one phenolic gear in the
drive, I am sure it is there to quiet things down.

Ian - unleashed. Great to see you are having a good time, and making useful stuff.

Very impressive work. Starting with internal threads.....OK, never Mr. Conventional, looking for the easy path. My first threaded
part ended up with left handed threads.....seemed a lot smarter to thread away from the shoulder on the part, hadn't really
thought that one thru.
Nice looking threads in the end, but nothing to thread them into.
The second part is still on a shelf somewhere, I think. 5/16" threads about 2" long, came out real nice, and RIGHT handed!
Very neat when a nut threaded on properly. Ta- Da!

Bill

 

[KeithB]

The college where I used to work had a Sheldon (English made) lathe; it also had one phenolic gear in the drive train.

Edited 7/21/17 change "Sheldon" to "Harrison 2000"

 

[Ian]

Internal metric threads against in tough steel wouldn't be my recommendation for anyone's first project, but I needed the part made in order to do other projects on the lathe, so no time like right then to figure it out. At least there wasn't an internal shoulder to deal with.

One of the reasons I went ahead and bought this lathe was to save money (sound familiar to all us fraternal bullet-casting cranks?) I have a lot of rifle barrels to thread, and the precision riflesmith closest to me that I trust gets $175 to start off for threading muzzles. The Marlin would be that much plus his hourly rate to R&R the barrel, shorten the magazine tube, and sort out re-mounting the front sight base. In other words, he couldn't afford to do it and I couldn't afford to pay him to probably lose money on the deal. I couple of jobs like this and I will have paid for the lathe right there.

 

[Pistolero]

Wow, at $175 per bbl that pays for the lathe pretty quickly, and the tons of other parts are
just gravy.

Bill

 

[Gary]

Come on Bill; that's like my wife telling me how much money she saved while buying a new ring on sale.

 

[Brad]

Come on Bill; that's like my wife telling me how much money she saved while buying a new ring on sale.

Wow, calling a man out for his creative accounting to justify a machinery purchase?

This is kind of like how much money we save by casting.

 

[Gary]

Yeah, I only used that line with the wife ONCE!!

 

[Pistolero]

Well, way better than just saying "Because I wanted it."

Bill

 

[Brad]

My wife and learned that if I talk about it long enough it just happens.
I need to start talking about a mill more!

In her defense she did tell me there was only one rule with the lathe. I was to buy something big enough that I didn't tell her I needed an upgrade in a few years.

 

[Pistolero]

Really smart wife, Brad. That is amazing forethought, most women don't think in those terms.

Temp thread sidetrack.
If I want to upload a video - what is the best format and how big a file is OK? I always resize
my pix to 1000 pixels across to keep from hogging bandwidth, but no idea on movies.
Ian's video looked really good, how big a file was that before uploading?
Bill

 

[Brad]

I upload to YouTube then post the link.
I created a YouTube channel. I tend to make the videos semiprivate. I think it makes them viewable if the link is provided but not easy to find otherwise.

 

[Ian]

Bill, I uploaded it to my utoob account and linked it through the post here.

 

[Brad]

Maybe our own Bill will become a utoob sensation! He could be famous!