Lathe chuck spindle attachment

This here looks a rather attractive machine particularly as it is on sale:
http://busybeetools.ca/cgi-bin/picture10?NTITEM ²227L Trying to find out more about it I looked at the manual but it is quite useless. One of the questions I had was how is the chuck attached to the spindle. The dealer tells me that there is a "flange" but any further details have not been forthcoming so far.
Are there any standards that would describe such flange attachment? Are there standard sizes? I am concerned about accessories (5C collet chuck??). This machine is BTW only superficially similar to the Grizzly G0602 which I understand has a 1-3/4 - 8TPI spindle.

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One of the questions I had was how is the chuck attached to the
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Michael
Probably attaches with threads as you mention. Don't buy from this dealer if he does not know or does not find out.
Bob AZ

Many lathe models from China have flanged spindles instead of threaded "noses". With flanged spindle mounts, there are either studs or threaded holes at the back face of the chuck body, and holes around the flange to match the fastening method.
Looking at the closeup pics of the chuck and headstock, shows the flange to be the same size as the chuck.
There may be some common chucks in the 5" diameter range (and possibly a little larger) that can be fitted/machined to adapt to the flange on this BB machine. Chucks much larger than 5" will likely require an adapter plate that the user will need to perform some machining to mate the chuck with the spindle. Oh, I noticed that an adapter plate is shown at the bottom of the description, and separate from the optional 5" 4-jaw chuck.
The machine features/specs show that the spindle bore is 1" and has a MT4 taper. The 1" bore excludes using a 5C collet draw tube.
Collet choices would be Morse tapers used with a drawbar, or adapt the MT4 to 3C collets, and use a draw tube. The 3C collets allow feedthru of material (feeding long stock from the left side), but the workpiece/stock diameter limit is smaller than 5C. Morse taper collets don't allow workpiece/stock passthru. Collets sized MT4 may be relatively expensive. MT3 collets with an adapting MT3/MT4 sleeve would allow cheaper MT3 collets to be used. A few MT4 collets in the larger sizes might be desirable.
There are adapters for MT3 to 3C collets, but I don't know if there are adapters that go directly from MT4 to 3C. The draw tube for the 3C collets may be the same one available for the 9x20 models, or possibly adaptable with (maybe) minor modifications.

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Enco makes (or made) a nice lathe with cam-lock chuck, that can fit a 5C snap handle collet setup. If you plan on switching often between lathe chuck and collets, cam-lock is a dream. The lathe you show is definitely not camlock, as you would see 3 add'l square socket ditties, for the cams.
I wonder if 10" is large enough for a 5C collet system..... your 1" bore would not be large enough for 5C.

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I just thought it might be an option as this guy installed a 5C collet on his G0602 which also has 1" spindle bore:
http://groups.yahoo.com/group/10x22grizzlyandthelike/photos/album/1896867786/pic/1239071546/view?picmode=&mode=tn&order=ordinal&start=1&count &dir=asc
In any case it was just to illustrate a point. I wondered if the "flange" thing would severely limit me in the choice of attachments. For a start I do not know what quality the chucks offered with this machine are and it would be nice to have the option to go with another manufacturer for replacements. Furthermore, the 4-jaw chuck available for this machine is only 5" which is a bit small. Does this mean one would have to manufacture a whole adapter for a bigger chuck? One has to believe that there are adapters available for this type of spindle commercially somewhere, but without further details how does one go looking for them?
Incidentally their 7X8 lathe also has a flange which I understand is common. LMS sell adapters for *3" flange*. That is the sort of standardization I was looking for. Things would be even simpler for a 9X20 with a 1.5"-8TPI or M39X4mm spindle. Adapters for 3,4,5, or 6" chucks are freely available.
Meanwhile I got a response from the dealer and here it is:
"We do not have exact dimentions of the spindle flange, but it is 5" in diameter and is machined to fit behind the chuck which comes with the lathe. the holes are approximately 3.723" apart. One side of the adaptor is machined in a similar design as the back of the 3 jaw chuck and the other side is machined to accept the 4 jaw chuck. Since you want to use a different chuck we suggest you wait until you acquire the lathe and the chuck then machine the adaptor accordingly. "
I am not sure what to make of it.

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You can make a better adapter plate than you can buy because you can fit it as carefully as you want to the exact sizes of the spindle flange and chuck back recess.
If you measured the diameters of the spindle flanges on the production line I suspect you'd see them increase continuously as the tool wore, then jump back to the minimum when it was replaced. An adapter plate to fit them would have to be at the large end of the tolerance in order to fit all lathes, and a sloppy fit on most, while you can make one exactly the right size for yours.
Look at lathe chucks in the MSC catalog and you'll see separate back plates for the common mounting styles. You fit the plate to the spindle, then shape it into a flange that fits snugly into the recess on the back of the chuck. http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1784923&PMT4NO=0
jsw

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Ah, I was under the impression that they are all made oversize for the final turning down on each particular machine. At least that is what the LMS adapters are.
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This is kind of my point: There are 297 adapters listed in that section. Which one do you pick for this machine? Personally I would prefer to get one that at least somewhat matches the spindle than have to make the whole thing from scratch. With a known common type such as "10 inch 3-jaw with a A1-6 mount" I know what everyone is talking about. The one adapter you linked would clearly not fit this machine. I looked at all 297 and could not decide which one would.

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All you need is a chunk of steel or iron the right size. I've made adapters out of scrap hydraulic cylinder rod, a cast-iron pipe coupler and a locating pin from an old Segway fender mold.
Barbell weights are the right shape, though the iron may be difficult to cut. A few days of cooking inside the wood stove might soften then up enough, it works well with flame-cut hot rolled steel.
Fitting an adapter to the spindle is easier if the adapter is on a mandrel between centers so you can check the fit and replace the adapter exactly concentric, to remove another half thousandths all the way around. You could bolt it to the flange to cut it almost to size quickly.
5" is a reasonable size for the chuck on a 10" lathe. You don't want it to hit the carriage. I have a 5" 3 jaw and a 6" 4 jaw and have to be very careful with the larger one, or set a stop.
jsw

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That presupposes a degree of skill on my part :-) I was doing a dry run in my mind and got stuck at stage one: Getting the right holes drilled in the right places if you cannot remove the flange and use transfer punches. But I guess careful measurement would suffice. The next stage would involve a very interrupted cut which presumably is not an issue with a lathe this size. BTW can you part the piece out by having the parting tool at 90 degrees to the usual direction? Cutting into the piece at the right angles with the tool lined up along the lathe bed? I have seen it done with a wood lathe.
The good thing is that one would not have to cut large internal threads for this spindle.
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Here is a question then: Say you have a 9" swing lathe and a 8" diameter, 0.25" thick plate of mild steel than needs a 6.5" hole bored in the centre. You cannot hold it on the outside in a chuck. You cannot clamp it outside on a face plate, even a wooden one. Not enough space for the clamps. What do you do? Would making an 8" sacrificial face plate and super gluing the work piece to it work? Would you cut the hole with a mill on a rotary table? None of the above?

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    No! The blade of the parting tool would need to be curved like a parenthesis on a radius to match the cut to be made. This is called a trepaning tool. A standard parting tool would bind on the outside below the cut.
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    What I would do is to mount the faceplate (which is probably larger in diameter than the chucks), coat the surface with double-sided tape, approximately center the workpiece, and using a live center with a flat pusher in it -- or a turned piece of aluminum with a large center hole drilled not all the way through, and use the tailstock and this to press the workpiece against the faceplate. Better if your pusher is turned to press near the OD and relieved a bit inside that.
    This is used to press the (slightly oversized) workpiece firmly against the plate to get the tape to grip firmly. Then (using very slow speeds) drill through the center with a bit which fits your lathe -- perhaps a 1/2" one unless you can find a Morse taper shank drill to fit the tailstock taper.
    Then, using a boring bar, bore through the workpiece slowly increasing the size until it is the right ID.
    Then -- put on the 3-jaw chuck (assuming that you don't need the OD to be truly concentric with the bored hole) expand the jaws inside th bored hole to grip the workpiece so you can turn the OD to something close to concentric.
    If you need the two to be truly concentric, turn the OD while still holding the workpiece against the faceplate with the live enter and pusher adaptor. Then shift to boring the OD.
    Yes -- the super glue (or a bearing mount Loctite) would work in place of the double-sided tape. You will need to use heat to release it.
    And -- while boring, it would probably help to have an extra sacrificial aluminum plate between the workpiece and the faceplate so you don't cut the faceplate.
    Of course if the plate which you are machining can tolerate some holes in its surface -- perhaps in places which would be machined larger later -- drill and tap for bolts to hold it to the faceplate..
    And yes -- you could use a rotary table and the double-stick tape or glue again on the mill to do the same thing. The finish of the bore will probably not be as nice, however.
    Note that you can probably use a larger diameter 4-jaw on the lathe than the 3-jaw because the jaws are easier to adapt to not stick out as far. My 12x24" Clausing has a 6-1/4" 3-jaw, and a 10" 4-jaw.
    In your particular described situation, a 9" swing lathe, and an 8" diameter workpiece, *if* your jaws for an 8" 4-jaw chuck have the last step only 1/2" thick, you could just barely grip the 8" diameter workpiece with the jaws extending only partially beyond the OD of the chuck. Be very careful when doing this:
1)    Make sure that it does not hit the bed or the wings of the carriage,     and that the tool can reach fully through the workpiece without     bringing a part of the carriage into contact with the jaws.
2)    Don't crank down too tight on the jaws. Extended even a single     step beyond the OD of the body puts an extra stress on them.
    Or -- you could perhaps make extended soft jaws for the 3-jaw chuck if it has two-piece jaws. You can extend them far enough to grip the OD of the workpiece, and make them of aluminum so you are less likely to damage the bed if you don't adjust things quite right.
    Good Luck,         DoN.

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Makes sense! Like making a hole in the head. Do I take it that you need various sizes trepanning tools to cut different radii?
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I take it at this stage you have removed the pusher and relying solely on the double sided sticky tape.
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From then on it is a piece of cake - it is that first step that I could not solve without engaging in what I considered a rather sporting activity. Glad to know it is an acceptable way to do it.
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Right. I allowed for that. I thought the holding would be better with SG than the tape.
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I was thinking a recess as I have done with wood. But this is simpler.
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That is what I thought. And using my boring head to 6" on my mini-mill is probably pushing it :-) I did manage 3-1/8"...once!
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OK, it sounds like additional reason to use the faceplate method.
I picked that example so you *could not* use the 4-jaw. I have run into that problem several times. I really wanted to know what is an accepted way of dealing with pieces that have a diameter approaching the lathe swing.
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Thanks a lot. I shall try this on a smaller scale (4") and be ready to duck if things fly at 550 rpm :-)

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    Yes -- you could make one by grinding a HSS tool bit to the proper radii -- including clearance.
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    Yes. Keep the lathe speed slow, and the cut depth small to keep the forces down.
    Hmm ... for the drilling, you could make a special holder which held a thrust bearing assembly with a bore larger than the drill which you would use to start the hole. You could crank the carriage into position (with the bearing well centered) to maintain extra pressure while drilling, since you don't need the carriage for the actual drilling.
    Hmm ... another way to hold it fairly concentric (assuming that your stock is truly round and near the desired size) would be a ring which slips over the OD of the workpiece and (with less than 1/2" radial size around the workpiece) and drill and tap four holes at 12:00 o'clock, 3:00 o'clock, 6:00 o'clock, and 9:00 o'clock and clamp it to the faceplate with two steel bars going from 12:00 o'clock to 3:00 o'clock and from 6:00 o'clock to 9:00 o'clock so they don't interfere with the spindle -- and the ends have to be cut to clear the bed. This, perhaps augmented by the double-sided tape, would hold things firmly in place.
    Hmm ... two rings -- one which is a fit on the faceplate, and the other on the (larger) workpiece, held together with bolts might make getting things centered a bit easier.
    Anyway -- with these approaches, you could use higher spindle speeds than you would find safe with just the tape.
    In any case -- use alcohol or acetone to scrub down the surface of both the workpiece and the faceplate to make sure that they are both free of oil and grease for maximum adhesion of the tape.
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    One of many ways. I've suggested some others above which take more time making fixtures, but which make sense if you are making multiples of these (e.g. the scales for your sundials).
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    It depends. super glue forms a rather brittle joint, so if you have an interrupted cut or otherwise bump things you could break the bond. The double-sided tape -- especially sufficient area of double-sided foam tape -- will give a very good grip, and be more immune to shocks.
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    Yes -- the torque needed goes up fast with increasing diameter.
    The rotary table and a "slot drill" (two flute endmill) of perhaps 1/4" diameter will probably work fairly well.
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    Yes.
    Actually -- you *could* -- barely -- with modified jaws. It is just more difficult to make jaws for a 4-jaw than soft jaws for a 3-jaw which is already fitted with two-piece jaws.
    Think of the special soft jaws available for the Taig/Peatol lathe. Those will handle a workpiece significantly larger than the chuck body. For a 5" chuck -- just make large pie jaws to replace the hardened top jaws -- *if* the machine comes with a chuck with two-part jaws.
    Hmm ... also, this sounds like an argument for a gap-bed lathe. The first few inches of the bed can be unbolted and lifted out to allow working with a larger diameter workpiece. There is some debate whether the removed section can ever be put back as precisely as it was positioned when the bed was first ground, but there are things where the gap bed is a winner.
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    Lots of ways to do it -- depending on the lathe, and how many of the same size workpiece you are making.
    What you are making is relatively thin so you don't have to worry about it clearing the carriage.
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    The larger the diameter, the more grip surface you have between the double-sided tape and the workpiece and faceplate.
    But in any case, I would not consider 550 RPM to be a good idea.
    First -- if the tape does let go, it could throw things rather hard.
    Second, 6.5" diameter means 935 SFM, which strikes me as a bit fast unless you are using something like carbide tooling and a free cutting mild steel like 12L14.
    Based on the cutting speeds chart for HSS tooling in the Jorgensen steel book:
Steel    SFM --------------- 1018    125 12L14    300 4140    120 (annealed)
Stainless steels below Steel    SFM --------------- 304    75 416    160
    Enjoy,         DoN.

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That is getting tricky...
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I like that.
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Acetone for the faceplate. Alcohol for me...
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I have not considered that aspect...
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I do. All the time :-)
Those will handle a workpiece significantly larger than the
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The problem arises with the Taig also. None of the chucks will hold a 4" piece. I do the insides with a boring head on the mill and finish on the Taig.
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No, no! I did say I shall try with *4"*. Yes, 550 rpm (the lowest the Taig will go) is way too fast for that too, but I have managed so far. The only way it works for facing is a sharp HSS tool with a small point radius. And a very slow and steady hand as one gets to the outside. To do the inside I need to bore only about 2" diameter. OTOH there is probably no point doing that as the mill method works just fine and it will provide me with only limited information about how the big piece would behave.
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Granted. But if I followed that I would be cutting nothing bigger than 1" diameters. The frightening thing about it is that to face the piece (1018) in question (8" diameter) one should have a lathe with low speed of 60. Back to cranking the handle...

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I've been reluctant to suggest the way I machine large arcs, but you seem to have some experience now.
I attach a pivot post to the table of the mill, drill the blank to fit on it, attach a long handle and manually rotate the blank into the end mill. Yes, the end mill is likely to grab and try to spin the work, more so if there is any play at the pivot. That isn't too serious while the blank is still a polygon because the end mill quickly reaches a gap. Once the arc is nearly continuous the depth of cut has to be very small. I use a small endmill at low speed, extend the quill all the way down and don't lock it so I can knock the handle upward, and set the drive belts quite loose, but it's still as dangerous as working freehand on a drill press. The worst one I've done this way was a circular tee slot, after the milling force damaged my undersized rotary table.
I mostly do this to round the ends of linkage bars and stop before the arc is tangent to the straight edge. http://picasaweb.google.com/KB1DAL/HomeMadeMachines#5265133136395165634 The wider hinge part was first clamped upright in the milling vise, with a shaft through the hole to position it atop the jaws, and milled almost to size across the top. A larger diameter piece could be clamped to an angle plate. The disk will vibrate if not well supported close to the cut.
If the disk can be clamped firmly to the mill table, raised on spacers, it can be cut nearly to size much more safely by rotating it slightly between cuts. The frequent reclamping is incredibly tedious but it would get your 8" disk close enough to finish with a light cut on the 9" lathe.
For even larger circles I set them up on a shaft and round them with an angle grinder, held so it crosses at an angle and spins the disk as it cuts. That's how I shaped the front tire for the sawmill. I haven't tried yet, but I think a disk could be turned fairly accurately on a wooden frame with a lathe bit on an X-Y table which moves crosswise, parallel to the axle. Think of an old foot-pedal grindstone frame. You could spin the disk with a sanding drum in a drill.
The right way is probably to buy the largest rotary table that fits on your mill. The disadvantage compared to a gap-bed lathe is that you can't detail the edges as much, you'll be limited to end mill profiles like vee grooves and corner rounders.
jsw

I did not have as much luck facing with the grinder. I made some plastic jaws for a chuck on my woodlathe and used an angle grinder with a sanding attachment but for some reason it did not work too well either. I have a feeling that the thing has to spin at a lower rate than 300 rpm to give the grinder chance to work (I am talking face work here).
Still, the on-going problem is the *inside* of the doughnut.
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I am certainly considering it as a viable option. Realistically I cannot get anything bigger than 6" rotary table on my mill and even that is probably pushing it. OTOH if one could do things that way it is a $1000 difference in capital expenditure :-)
BTW can you put a motor drive on a rotary table so it turns at a constant rate?

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    There is a stepper motor drive for the little Sherline rotary table, which can be used with a controller/keypad:
    <http://www.sherline.com/8730pg.htm
    <http://www.sherline.com/8700inst.htm
    With a CNC milling machine, you could even use it for engraving the time markings on your dials.
    Enjoy,         DoN.

Some rotary tables can be motorized to run continuously while milling, but I expect that some of the light duty RTs should probably just be used for positioning.
I was using a motorized RT for a while, and it seemed to work very well (hobby, not production speeds & feeds). I used a small Oriental Motor gearmotor, chain and sprockets and a Phase II 6" horizontal RT. The RT was turning very slowly, less than 2 RPM, maybe considerably slower. It's a method I wanted to try, for cutting disks from sheet/plate stock without center holes.

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So, it bears further consideration. I guess the next question is "How fast can you rotate a rotary table?" :-)

There aren't any multi-part bearing assemblies (roller, ball) in the 6" Phase II RT that I used, just plain polished (finely ground) steel sufaces against machined cast iron, with the parts well-oiled with 80 or 90W gear lube. Since old lathes could spin hundreds of RPM (with lighter oil), I suppose a RT could be run fairly fast if it's designed and built well enough. The table's support surfaces are significantly different than a lathe spindle as the two machines are designed for different purposes/applications.
Some RTs are 40:1, others are higher turns per rotation. Worm reductions typically have slow output speeds although heavy duty models can handle some serious loads. If one were inclined, the worm of a RT can be disengaged in many models (or removed), so the table stem could be driven from the back side or bottom, depending upon the orienation (of the RT, not the operator).
As long as the RT isn't routinely subjected to the side loads of turning down diameters, push knurling and other typical lathe operations, a RT may be suitable (just speculation) for occasional cutting operations similar to facing cuts on lathes.
If the table's stem support/bearing surfaces wear, the accuracy of the RT is diminished, so an overhaul may be necessary, possibly requiring boring and a bushing or sleeve installation.

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That piece fit on the lathe after sawing it roughly to size. I clamped the square blank flat on the bandsaw table with tee bolts to cut off the corners. Then I set the saw upright and followed a scribed circle as far as the wide blade allows, then opened up the kerf with a chisel to make clearance the next cut.
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The upright pivot post is held in the vise, the disk rests on 1-2-3 blocks which raise it above the jaw tops. Tee slot clamp bolts clamp the disk onto the 1-2-3 blocks, leaving a small space in between to mill tangents to the OD. It's slower than sawing because of all the reclamping but doesn't risk cutting in too far by accident, and leaves only a little metal for the lathe to remove.
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The ladder-shaped frame of my sawmill is the model. Both wheels needed truing and the front one considerable flattening. I used the crosspieces at the inner ends of the wheels for tool rests, ie to hold the grinder steady.
You could make a similar frame out of wood by laminating 2x4's with the ends alternating to form glued finger joints. I'd make two side-by- side rectangular bays, the second providing a tool rest for faceplate turning.
The faceplate could be a large pulley faced with plywood. The bearings on the motorcycle wheels were tight enough to use one as a lathe faceplate, though the protruding axle interferes. If you did that you could drive the tire by friction or remove it and run a vee belt on the rim. I used the sprocket only because I needed to transmit several horsepower, it required a separate countershaft.
I think an X-Y table would be stiff enough for a tool rest. I acquired one plus the headstock from a scrapped SB lathe and a brake lathe tailstock to build a large wheel lathe, but haven't needed to set it up yet.
jsw