Which would you choose?

I believe you're ready for this suggestion now:

A well-worn old industrial lathe just might do everything you need, if you can find a working one cheap enough. For example:

They aren't worth much if the bed is badly worn or a valuable feature like threading doesn't work, but you don't seem to need high precision or custom threads.

A leather belt drive, threaded spindle and single phase motor decrease it's usefulness for a business but not so much for a home shop.

A problem is finding a cheap one that isn't hopelessly gonzo unless you buy three $500 factory repair parts. That can be an issue with South Bend, for instance. Mine has several non-standard and home made replacement parts, some hacked out by the trade school students who (ab)used it before me.

I think you've rehearsed your spiel on us enough to recite it in machinists' terms to the seller, who hopefully understands the lathe's condition and would know if it would serve your needs.

Good Luck Jim Wilkins

In which case you probably will eventually want two different machines -- one set up for each job.

Even the Taig should be able to do that with the riser blocks.

That -- or the Taig with perhaps even *two* riser blocks? Not very rigid, but probably sufficient for edging the face. I would have to check whether two blocks stacked up would give you sufficient center height to turn a 9" face.

O.K. I presume that you would like to make the gnomons tapered? For that, you do what work is needed on a cylindrical basis (probably between centers) and then shift to between centers with an offset on the tailstock so you can produce a nice smooth taper.

Hmm ... part of that cylindrical work on the gnomon might be to turn a shoulder, and then thread up to the shoulder so the gnomon could screw directly into whatever it mounts to -- as long as the gnomon should be perpendicular to the mounting point. That saves you from having to stock screws and work at hiding them in the assembled sundial.

Between centers for sure then.

I just went down and verified. *My* (rather old) Taig has a Jacobs 1/2" capacity chuck which screws onto an external thread on the tailstock ram. IIRC, it also screws onto an arbor to allow you to use it powered in the headstock as well.

That can be a problem, too. The Mini-lathe or the Taig are low enough power so you can afford to make mistakes without producing serious catastrophes. A 12" or 13" lathe is a different matter, let alone larger ones. For *those* the class first would be a *very* good idea. And you *will* learn things from the class even with the smaller machines. (Granted, I never took such a class -- but I learned (as an Electronics Technician) from some good machinists at work, and as a result was one of the few technicians allowed to use the machine tools in the building.

Enjoy, DoN.

I have been ready for some time :-) I monitor Craig's List daily within a reasonable radius - transport of such equipment could also become an issue as well as all those others you mention. I also monitor the local auction weekly. So far things have not panned out. Small community and all that. I have printed out a copy of an excellent treatise on assessing a second-hand lathe which I propose to memorize next time I go to inspect one. Meanwhile, however, I am trying to keep my eyes and mind open for all sorts of options.

Unfortunately, I have not been able to go to Vancouver recently. If and when I finally get to go, I shall do some homework on their Craig's list. I will also be able to drop into some important shops. If nothing else I should be able to handle things there.

I have two pillow blocks and a large pulley and 1" shaft ready for one of them :-)

You see no other issues except rigidity? According to Lee Valley a pair of risers (head and tail) will increase the swing by 2", so I make it total

81/2" with two pairs (but only headstock needed for my prurpose). How about speed? The taig in the basic configuration only goes down to 525 rpm with an AC motor (1725 rpm). I have thought that a DC motor would be the thing but that raises the price even further and the mini becomes even more attractive.

Tapered or different patterns.

Absolutely. I have done one like that so far using a die to cut the thread. Is that not quicker to do than on a lathe?

One of the reasons I am hesitant about the Taig. The descriptions from various sources are rather confusing. Lee Valley sell 1/4" chuck to go on the 3/8"-24 tailstock.

No argument! Such course would be an excellent idea, which is why I have my name on the list. But it becomes a matter of allocation of resources. Then there is a matter of my predisposition to learn things by myself. Many skills which were supposedly taught to me over the years were learned by the time honoured method of "see one, do one, teach one". I still have nightmares about some of the stuff one did in one's youth through arogance, ignorance, stupidity and total lack of guidance and supervision. But that is no excuse now, one should have gained the wisdom of age. Fat chance...

A flat-bed auto wrecker works pretty well. The dealer I bought my lathe from is an industrial rigger and that's what he delivered it on, tied down securely. He slid it down the bed into my garage, just inside the door, and it has stayed there. Doesn't matter, the old car behind it on jackstands isn't going anywhere.

If you buy old machines it's very helpful to know all the second-hand dealers in your area. I've figured out mileage-efficient loops to visit them a few times a year, or whenever I have business in that area. I keep some cardboard and rubber-backed rugs in the CRV to protect its interior from greasy old machine parts, and installed the optional rear child seat tiedowns in the roof. That particular vehicle has a somewhat fragile plastic folding table over the spare tire well (which is a storage tub for wet stuff, ie the kitchen sink) so I covered the hatch area floor with plywood.

Try to find an old Starrett or Brown & Sharpe catalog so you'll know what all those mysterious old gadgets are and how they can solve your problems. With CAD/CAM and DROs the old layout and measuring tools are obsolete, except for home shops.

Jim Wilkins

Actually I would buy the B2227L from BusyBee, I know its morethan you want to spend, but would probably last you a lot longer. For a small lathe its very beefy. Much more so than the minilathe.

Here's a thread about it on cnczone.com

I started on a mini-lathe, and its fine, but eventually wound up buying a 12 x 36 lathe for the garage. I might still buy one of these for my basement workshop, even though I don't need another lathe.

or on Victoria's Craig's List is this:

NOT for a miser, but it will last forever! and still sell on your passing to enrich your estate!

Mike in Burns Lake

:-)

[ ... ]

Hmm ... thinking about it -- you would need to make an L-shaped mount for the toolpost to get it far enough out to pass in front of the workpiece at center height. But *that* is something which you should be able to make using your mini-mill.

Speed would depend on the workpiece material used. Steel would need rather slow speeds at 8 1/2" diameter. Let's see -- that works out to 1168 SFM at the maximum of 8 1/2". O.K. For aluminum, you can handle it even with HSS, and for brass you would probably want a very sharp carbide, or PCD (Poly Crystalline Diamond), which is not as expensive as you might initially expect. :-)

Hmm ... I thought that it ran slower than that with the multi-step pulley which came with mine. I do know that the top speed is quite scary. :-)

But a different AC motor -- at half the speed -- should do fine.

O.K. The patterns will probably be freehand with a half-round file.

You produced a shoulder as well as a thread with hand tools?

The problem with a die is that it is easy to start one out of line and then very difficult to get the thread back in line.

And -- if the diameter is an unusual one, dies to cut that thread can be quite expensive.

Yes -- a die can be quicker -- if you can grip the workpiece firmly enough. But lathe cut threads can be a nicer appearance than most die cut threads.

[ ... ]

The 3/8-24 tailstock thread is the same -- but various size chucks are available with that thread -- and the one which came with mine was 1/2".

:-)

Enjoy, DoN.

Yay!

I am quoting their web site.

And this is where the total cost begins to equal or exceed the mini :-)

I cheated. The shoulder was there already.

Tell me about it! I routinely chuck my gnomons (even those without a shoulder) in my drill press, hold the die in the drill press vise and thread that way. So far so good...

But if you have a lathe can you not turn the diameter to something usual? I did this in the drill press with a file. Fortunately it only needed a small amount to take off.

Gripping strongly has not been a problem. Chewing up the piece by doing so was.

Right now it is 3.5 degrees C in my "workshop" and I do not really want to be there :-). I was supposed to get my woodworking stuff in order (I seem to be doing more of that than I thought I would have to) which included making a router table and extending the work bench. I made the router table before the weather hit. I got as far as the planning stage with the bench. Still, an opportunity to do some homework. I have also developed a line of clamp knobs from bottle tops, 1/4"-20 bolts and epoxy. They are ugly but cheap and can be made in the warmth of the heated house.

I wonder what there is in the gagage that is going to freeze...

It's easier if you leave extra stock on the far end to clamp onto, and a short turned-down stub to guide the die straight. If the die cuts a shallow thread on the stub it will self-align and bite well into the full-diameter section.

If the die needs more torque than the work will stand I thread it most of the way on the lathe first. Then the die turns easily and stays sharp longer. For me at least dies seem to cut smoother when they only have a little metal to shave off. You can run the die on backwards to extend the thread start and smooth it with the less-used edges.

Since you have a mill now, you can cut one surface down to a polygon centered on another cylindrical part quite easily. To cut smaller, extend the shaft out the end of the vise and turn it slightly after each cut. For a large disk with a good round center hole you put an axle through the hole and rest the axle on the vise jaw tops or parallels, clamp the disk upright and mill off flats. The axle can be much smaller than the hole. When you have enough small closely spaced flats, round them with a file and belt sander. For your thin brake- rotor-shaped disks the mill should cut lengthwise to reduce vibration. You could make custom taller vise jaw pads and C-clamp them near the top. An undersized R/T will work better if there isn't much metal to remove around the edge of the disk.

This is also an easy way to round the ends of linkage bars etc:

A trick that's claimed to work is to drill a slightly undersized hole between two hardwood clamp blocks and sprinkle in powdered rosin, like baseball players use for grip. Or scrape some off a tree.

I saw that in a gunsmithing book as a method to unscrew tight barrels without scratching them. I don't do gunsmithing but it's one of several well-documented crafts with good tricks that can be used elsewhere. Others are watchmaking, aircraft sheetmetal and model steam engines. I haven't found much written about my real interest, industrial prototyping and R&D.

The most useful watchmaking idea was the button / disk technique for accurate hole layout on their manufacturing jigs. The disks are circular drill bushings whose radii add up to the desired hole spacing. When pushed together they locate the centers very precisely. The OD can be turned to the accuracy of your best micrometer, so potentially you could space holes to within 0.0002".

Rough out the disks, drill and ream the center holes, then turn a snug- fitting shouldered plug to fit the holes and finish the disks, and leave it in place in the chuck until done. I ream them all 0.125" and use a 1/8" spotting drill to drill the work. Then I put dowel pins in the holes and recheck the measurement. If it's good I center the dowel pin under the mill spindle, drill and bore.

You can make a custom index circle for an R/T by turning the disks to the chord distance between the holes and clamping them around a central disk, which you shave down until the circle of disks closes into contact. The index hole disks must all be the same diameter but the actual measured size isn't critical, so you can turn them to match the smallest, or finish them all without moving the bit.

This relies on measurment and hand fitting, not so much on the accuracy of the lathe. If it's badly worn you make a separate simple headstock with ball bearings and drive the back end of it with a dog from the lathe spindle. Offset the new spindle higher and to the rear, driven by a belt, for larger work. Then you only need to raise the toolpost which should be more rigid than a cantilevered adapter. The belt drive is your speed reducer.

Here is a simple way to adjust the spindle bearings parallel to the bed without precision machining. The end flanges could be bent up if you can't weld. Level the shaft by shimming under the lower block:

Four-bolt pillow blocks on spaced parallel plates should also work.

You could have a roughly rounded disk welded onto a mild steel shaft for the faceplate and turn a center point on the protruding end of the shaft. I would make the welded steel disk small and bolt on a full- sized aluminum faceplate.

Mine is twice as warm, 7C. It serves as my winter refrigerator.

Cheap, simple, effective. I've used plastic and copper water pipe caps tapped for the bolt and backed up with a nut. Iron pipe caps make very solid knobs but they cost almost as much as commercial thumb screws, which I can get in a surplus store.

Some hardware stores carry plastic knobs that press onto socket head cap screws.

I make large knobs for the release fitting on hydraulic jacks out of a knurled disk of aluminum scrap, bored to a press fit and with a milled slot for the cross pin. If you don't have a knurl, roll a coarse file or rasp over the disk. They give much better control than the slotted end of the jack handle for carefully lowering the load.

Most household chemicals seem to freeze without bursting the container, becoming a slushy mix of small ice crystals rather than a solid rigid block. They do have to survive warehouse storage.

Jim Wilkins

That is more or less what I do. It goes only so far: The 1/8" gnomon likes to twist if too long. Fortunately the material is dead easy to cut.

Maybe I should buy one...:-)

The other important thing I learned is that 14-20 is *not* 1/4"-20.

I *think* I got that.

Normally you would do this on an R/T?

I use it for soldering. Maybe that is the answer. That would mean having the gnomon stationary and some sort of die-holder chucked in the drill press.

Knife-making. Most of my early learning came from there.

I shall have to read this a few more times...:-)

Same for this. Although the picture looks like an assembly of all the parts waiting on my shelf :-)

Anything below 10C and the enthusiasm for the hobby begins to fade. Even with a triple layer of clothing, woolly hat etc.

Or some that fit standard hex bolts. In fact those were the cheapest - $1.10 a pop. I have not priced out mine but they should be considerably under that, what with garage sale loot and all. BTW my local hardware store does the knobs for *$8.30* a pop! I had to ask to make sure. Could not believe my eyes.

As long as the hydrochloric acid and ferric chloride stay in their bottles all will be well. Normally this is not an issue locally, but this year our temperature has been consistently below the seasonal average. Must be the global warming I suppose...

[ ... ]

Well ... the motor on mine is an inexpensive motor, and you should be able to pick up a used motor with half the speed for not too much. The main thing is that you want one with the same diameter shaft, since you can't bore the motor pulley out to a larger size with the lathe without a motor. :-)

There is a limit as to how much horsepower you can pump through that ultra-skinny belt, so there is no point in going for expensive motors.

Let's see -- you're in Canada, aren't you? In that case, you may have 50 Hz power instead of the 60 Hz in the USA. That means that the motor speeds will drop by a similar ratio.

Now -- the fastest induction motor on 60 Hz will run somewhat slower than 3600 RPM (probably 3500 or 3550 depending on slip) from 60 Hz. That same motor would be 3000 (2900 or 2950) on 50 Hz. For convenience let's work with the synchronous speed, even though it will run somewhat slower. Anyway this is for a 2-pole motor.

A 4-pole motor would be 1500 RPM, and a 6-pole motor would be

1000 RPM. I've seen 900 RPM on 60 Hz (presumably 8-pole), which would be 750 RPM on 50 Hz.

Now -- that would be with the middle set of steps on the pulleys (equal diameter in and out). I would think that the pulley could get the spindle down to 200 RPM or so with that motor. (Maybe I should actually measure the speeds on my lathe?

:-)

O.K. That helps -- as does a sliding die holder on the lathe. But for the larger diameters, you would have to start the die under power, and then switch out of the lathe to manual operations.

If something usual will indeed be strong enough. There are times when you want a larger diameter for strength, but an uncommonly fine thread to engage in fairly thin material for the female thread.

O.K. Beware of the side pressure of the file popping the drill press's chuck off of the spindle and leaving it (and your workpiece) skittering around the room.

That is where a collet helps -- assuming a cylindrical surface for the collet to grip. Tapers make life more difficult.

I can understand that. About 38.2 D -- kind of nippy, though better than -40. :-)

Warmth is *really* needed if you want the epoxy to cure in a semi-reasonable time. :-)

And 3.5 C? Nothing likely. But get colder and ...

Anti-freeze*? :-) Glues? The epoxy itself? Oil should have no problems, though grease can get thick enough to do no lubrication for a while. :-)

Good Luck, DoN.

* Yes -- anti-freeze will freeze at a higher temperature than the optimum mix of anti-freeze and water.

[ ... ]

Or -- turn a piece of aluminum to a sliding fit on the gnomon, slit one side, and clamp it in the lathe chuck or in a vise to clamp the aluminum down on the gnomon. This should be a good grip. (It could even be used in the drill press chuck if the total diameter is small enough to fit the chuck.

[ ... ]

Be warned -- *don't* use machine tools while wearing gloves. They can catch on the chuck jaws or on a dog or whatever and wrap your arm around the workpiece or the mill spindle. If you can't keep your hands warm enough with a close space heater, *don't* work there.

[ ... ]

Neither of those are common household chemicals, both have lots of water in them, and so the question of what is the freezing point is a function of how much of the other things are in there with the water.

I would bring both into the warmed house if I were you. Or at least put each in a soft plastic container surrounding the glass one, so if the glass breaks, the plastic keeps the fluids away from other things.

Be careful with both of those substances.

BTW -- *don't* use either near your machine tools They *will* rust like mad. Go outdoors to use either (unless you have a fume hood).

Good Luck, DoN.

If the lowest spindle speed with a 1750 rpm motor is 525 rpm then half-speed motor (875 rpm - 8 pole) will still get me 260 rpm (give or take) - still pretty swift. BTW quick search shows that such motors are a) rare as hen's teeth and b) expensive. To me it would make more sense to strip a treadmill or something and use the DC motor with speed control. Or buy the mini in the first place :-)

But that is still better than -80. Everything is relative. Do you know many workshops with ambient temperature of -40? I know that when Russians evacuated all their heavy industry during WW2 to the Urals some of the factories operated without roofs. But that is probably extreme and a major difference between a hobby and getting shot by the KGB (sorry, NKVD then) for refusing to work on the thin pretext of being frost-bitten.

And paint...

When I was young and living in a bed-sitter one way of telling room temperature first thing in the morning was to observe natural phenomena. Breath begins to condense at about 12C. Below 4C the cooking oil (at least the English cooking oil of yesteryear) is reluctant to flow out of the bottle.

When you say "turn", you don't mean....?!

I guess my 10-ft scarf is right out, then... :-)

They are in plastic and triple-wrapped.

Ferric chloride has never given me problems. No fumes to speak of. Unimpressed wife if you wash the bowls in her sink. HCl is a different kettle of fish...

Here is a dummy setup for roughing out a curve concentric to a hole:

The part is a clamp to hold an indicator on the Clausing mill's spindle. I bored the hole first and then cut away the rest. As you can see this aluminum part was finished on a rotary table, a lightweight no-name one that wouldn't handle this job in a similar piece of steel. The vise setup is much quicker than centering and clamping the part on an R/T, and safer when the curve ends in straight tangents where the end mill can grab, rotate the table by its free play and dig in badly.

When I blend a curve to a flat this way, I set the end mill to the height of the flat and then lower the table (you'd raise the spindle) about 0.005". The line of tangency won't be exactly radial but that is invisible, whereas cutting too deep leaves an obvious step at the end of the curve.

I usually clamp the shaft horizontally in the bench vise with the end protruding slightly and align the die parallel to the jaw end by eye. A square end on the blocks would let you do the same. This is for large coarse threads, for small ones I square the die with a drill arbor or female center in the lathe's tailstock.

Alignment would be easier in a drill press vise. Push the shaft toward the jaw with the die and tighten just before it makes contact.

Once the die starts to bite you can control the whole assembly with one hand, slide the shaft out a little to give the die some clearance, and use the other hand to retighten the vise.

Or if you put the starting stub on the gnomon you can align it in the drill press and then cut the full thread in clamp blocks.

I have the Hrisoulas video but not the artistic ability. My best effort has been compared to a prison shiv.

Here is an example:

disks are the black hardened cylinders on the upper left jaw, with dowel pins protruding. The upper right jaw shows the hole pattern that matches the pins and tapped hole on the chuck. The pin spacing appears to be 1-5/32" but they are too short and rounded to mike directly.

The chuck is like one from the old Holtzapffel drawings. Rotating the outer knurled ring cams the pin plates about 0.050" in and out. It's used to turn delicate rings such as lens retainers, by closing it half way (I think) and cutting a step to clamp the part securely all the way around. I didn't waste large enough stock to reach the center because I use 5C collets for smaller tubing.

I turned all three disks down until they fit in line on the chuck pins. The middle one pushes through with slight resistance, less than its weight, so tilting the chuck until it slips through is a very sensitive way to test the fit.

I didn't drill through them, but drilled and reamed the first hole at a punch mark and then used them with dowel pins to center the mill spindle for the other two. Since only the outer holes are really critical, I put a dowel pin in a collet, lowered it into a disk and adjusted the mill table to get the same feel when sliding the center disk between them as on the chuck pins.

Isadora Duncan

Jim Wilkins

I have managed to screw up the treads this way all the way up to 1/4". Hence the drill press.

Yes, once I got the beginning the rest is easy.

I relate to that.

That one is beyond me..

I do not dance as well...

The use of treadmill motors is fairly common. There used to be a treadmill motor and controller offered by a surplus house, and one common modification was to eliminate the safety feature (for a treadmill) of requiring the speed pot to be turned down to zero before it would start. Obviously a pain with a lathe. :-)

Agreed. The reason that I mentioned -40 -- without telling which measurement system -- is that -40 is the only temperature at which it does not *matter* which system you use. K and R are eliminated, because they both start at absolute zero, so negative values don't exist. C and F are the same temperature at -40. :-)

:-)

[ ... ]

Hmm ... I was in the shop this afternoon -- and my breath was not condensing. I had an electric heater by my feet running to keep the feet a bit warm at least -- and presumably the somewhat warmed air did come up past my face, but I did not notice that. :-)

But the waylube was noticeably stiff in the surface grinder table. I was working to thin down some open-end wrenches so they would fit the tap chucks on a couple of TapMatic tapping heads. I now finally have a full set of wrenches for the two sizes. (Of course, they should have come with the heads -- if I had bought them new. -- But those would be cheap stamped steel wrenches anyway. These were forged steel ones which simply had too thick a head to fit in to the milled flats.

Enjoy, DoN.

I am supposed to start up my mill from zero.

Or you could be a lizard. Have you saved up to 15% recently on car insurance? If you do not have the same Geico TV commercials this joke is dead...

Somebody posted a recommendation here for the Craftex B2227L lathe with a link to a discussion forum thread. The first 6 pages fo the thread (I went no further) dealt with what viscosity the oil in the headstock should be. Apparently when started up in the cold workshop the lathe was slow. It got better with oil change!