See Dropbox for "davis_lathe" and "davis_tools" photos. It's a rather heavy
12x36 machine from around 1910. The headstock as shown must weigh 125 pounds. Needs a good cleaning and painting. Came with matching jackshaft and motor mount in redneck style. Not bad for free.
I don't know very much about lathe history, but one thing I've never seen is that big lever on the headstock. It seems to internally swtich the first stage of feed gearing among three ratios. Like the predecessor of the quickchange gearbox. This lathe relys mostly on change gears.
It's not quite the gloat I though it was, now that I've gone through the boxes. No collet hardware other than the collets themselves. Lots of ancient tapping heads for a drill press or lathe much larger than this one, and a taper-mounted turret for a similarly larger machine. One plus is a "Clippit" flat belt clipping/splicing contraption.
Any idea what that compound slide is from? Doesn't fit the compound base well enough to use. Looks very old.
In the tooling photos, we have: one bucket dogs, one bucket changegears of all types, one bucket tap heads and turret (visable at top), one box large toolholders, one tray wrenches and toolholders, one tray of small parts/cutters/bits/etc, one bucket faceplates and a 3-jaw, one box misc larger devices, one tray collets, one large 4-jaw with last work still clamped, one tray bits and cutters. Also has a follow rest and a very rusty steady rest.
So that's it. I've either got a long project head of me or some possible income. I'll probably sell most of the accessories that don't fit it, since they're for something far too large for me to own. We'll have to see about modifying the compound slide or getting something that fits.
Absolute pile of crap, ship it to me and I'll ensure that it gets properly disposed! Seriously, it looks like a great retirement project, almost like a lot of the "stuff" I buy on Saturday mornings. Gerry :-)} London, Canada
It could be a clutch that engages the spindle gear with the stud gear out to the rest of the change gearing.
The lathe is in the "modern" configuration for gearing, having the leadscrew and feed rod combined. I don't recall from the pics, but you will have to find the left-end bearing box for the leadscrew (right end is still there), and with that the brackets/setup to get the gear set on the end of the leadscrew meshing with the rest of the change-gear train. Looks like it does not have power cross feed, only power long. Frank Morrison
I have all the parts, they're just buried in these boxes. It seems to be complete.
That lever's more than a clutch. It's marked 1, 2, 3 and on each setting gives the gears a different ratio. There are two external gears that connect to whatever's in the headstock. One's driven by the stud gear off the spindle, the other is output. Three distinct speeds on the output gear. It then drives the rest of the system. The latching F/N/R tumbler lever disengages the drive train.
It does have power crossfeed, through a setup like an SB9. Either/or long/cross with a clutch.
For those who don't know its URL by heart, check and click on the yellow [ Dropbox ] bar.
Image names (until they eventually get moved into a "retired files" directory are (for those who prefer to use a tool other than a browser to download the files for closer examination):
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and
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I noted no explanatory ".txt" file accompanying them. It is good practice to include such a file. Note that rec.crafts.metalworking is not the only group which uses the dropbox, so don't depend on others having seen your article to understand what the photos are about.
O.K.
Hmm ... my Clausing has three things which switch the ratio of the threading/feed leadscrew. The first (in order from headstock to leadscrew) is a sliding gear with a knurled handle sticking out trough a hole in the cover. The second (or perhaps third) is a paddle lever on a vertical shaft sticking out of the top of the quick-change box. The third (or perhaps second) is the toggle lever on the front. It sounds as though yours have the second only in that lever on the headstock.
It might help to see a close-up photo of the threading chart (right-hand upright of the headstock) which might give some clues as to what is what. It is far from legible in this photo, and would probably need posting with no quality trade-off and no cropping to remain legible. Don't bother trying to e-mail the photos to me, they would be too large, and as such, be rejected by one of my anti-virus features.
At a first glance, the collets threaded on a wire on top of the set of collets in the board appear to be stock feed collets -- mounted to the left of the spindle for feeding bar stock through a lever style collet closer, so you can feed without having to stop the spindle after parting off. I could be mis-identifying them, however.
That last looks like something good to have (especially if you have the clips as well), given the drive pulleys.
I'll agree that it looks too large for the cross-slide. Can the tool bits be adjusted to center height with that compound and the large lantern-style toolpost?
I see something else which looks interesting. The square rod on the left side of the cross-slide with the rounded end. There isn't enough resolution after compressing the images to tell, but is it threaded? Note the swinging hook below it on the carriage. I think that with a pair of nuts on it, one knurled and the other perhaps for a wrench, it can be used as a repeatable depth setting for threading. Swing the hook up, bring the tool in to just touch the workpiece, run the knurled nut in until it touches the hook, and tighten the other nut behind it. This will allow you to back the cross-slide up to clear the workpiece while running the tool back to the right-hand end of the are being threaded, and then you crank in until the nut touches again, and feed a bit more using the compound, and cut your next pass. It would speed up operations doing single-point threading, and looks a lot more rigid than the typical threading stops which clamp onto the dovetail behind the cross-slide.
I see a follower rest (under the green lampshade -- Tools2), but I don't see a turret (presumably for the tailstock taper) -- unless it is under the follower rest. Which photo is it in? Tools6 appears to have a firm-joint caliper under the other tool bits and debris.
One of the things in the box under the board of collets (Tools4) looks like a custom gear or pulley puller -- for a single size.
Do you find matching holes on one side of the carriage or the other to match those in the follower rest?
Looking at the apron, with the gear sticking up from it, I would guess that there is a matching gear on the cross-feed leadscrew, accessed through a hole under the carriage. At a guess, the double-ended ball handle (with no crank) selects between cross and longitudinal feeds, and the round disc to the right of it is the clutch which couples the leadscrew to the feeds. This is supported by a keyway in the leadscrew. It means that you won't need to use (and shouldn't use) the (worn) half-nuts except when threading.
Are there two or three inverted V-ways on the bed? In any case, the steady rest (to the right of the carriage -- "Lathe3") doesn't look designed for that bed, as it has *two* female Vs -- unless it is intended to turn it around so you can mount it with the steady fingers to the left or the right.
I presume that the bearing sleeves on the big countershaft (Lathe7) fit to the support frames (Lathe8). I would guess that the original plan was for the motor to sit between the two I-beam sections, with its shaft sticking out through the hole to the right (probably to the left when properly installed on the lahte), and a smaller pulley on the motor shaft is V-belted to that gigantic pulley on the countershaft. (it could also accept a larger motor on the "arms" extending behind it in the photo.) I think that the intention was to mount it to the wall behind the lathe, with the "arms" pointing down (which would allow the motor to be between the mounts, with the pulley sticking out to the left where the big pulley would be.
I think that I see where the screws from the cradles fit into the bearing sleeves, but the resolution makes that identification questionable. I would like some closer photos of just the bearing sleeves to verify this.
I find the smaller pulley to the right (as shown) interesting -- perhaps to drive some accessory power feed. Or perhaps it is a sliding actuator for a dog clutch to stop and start the lathe while allowing the motor to continue running. This sort of thing would be needed with the original line-shaft power, since a single shaft would be powering many machines in the shop at the same time.
It looks as though you have a pretty good 4-jaw chuck for the lathe, but it is missing the backplate -- unless it is in one of the boxes -- perhaps under the stack of faceplates in the bucket.
Hmm ... the lever (Tools3) to the right of the handle bar on the left-hand tray) *might* belong to the tailstock -- to clamp or release the bolt down to a plate below the bed to allow the tailstock to easily be re-positioned.
One object in the tray to the right of it looks like a plain miling cutter for a specific gear tooth form -- and a certain range of tooth counts. You would need a mill and an index head to make proper use of this, of course.
A lot of the stuff would require a bit more of a hands-on introduction to have a chance to guess the function.
Oh -- is there a 3-jaw under the faceplates? Perhaps also a backplate for the 4-jaw?
But without a backplate -- unless it is under the faceplates.
Right now -- I don't see anything in that batch of photos on which I would be likely to bid -- lacking better identification. I'm not sure what you are calling "tapping heads". More detailed photos, excavated from all the other clutter which surrounds them, might allow better identification.
How much modification would be needed? Does it work?
Lots of them above -- including guesses -- as best as I can do based on the photos.
Text explanation's forthcoming, just wanted to get the photos up pronto.
I'll get a photo of that, although it's not too interesting. Can't get out to the garage right now.
I'm not much of a collet guy, so I can't help with that. Not for this lathe, though--it only has a 1/2" spindle bore. From memory, the ones on the wire are around 1.25" in diameter. The collets in the board have about 3/4" shanks (or whatever the collet equivalent is) that are smooth for most of the length with the rearmost 1/4" or so slightly larger.
The bits are perfectly centered, just the dovetail isn't right. Looks like it was used like this for years--no idea what kind of work was turned out.
which clamp onto the dovetail
Yes, that's right. I noticed that when I got it--one of those very vintage features.
The turret's taper-end is visable sticking out above the follower. The body is a cylinder with a big slot in it. In the slot is the turret disc with 6 or so different size holes. Disc is slit almost in half so when you clamp it in place the tools are secured.
This machine came with several of those. I actually gave away a similar one last year after no one could find a specific use for it.
Yup, they're there.
The ball knob is the clutch, the round one's the selector. Unscrew, slide up or down, screw back in. How does one avoid using the half nuts when making cuts? The nuts are the only thing that couple the carriage to the leadscrew. Cross is driven by a sleeve with a key.
That's what I was thinking. The lathe just has one V-way for the tailstock. It fits perfectly, so it looks like I would work. I'm not positive--it's one of a couple items that seem to have been stored underground.
I would like some closer photos of just the bearing
That's correct. The frame is made out of really rough iron--at first I thought cutting torch but looks more like cold chisel. How it's mounted is really ingenius, as far as hack engineering goes. The wider channel section sticking out was bolted to the underside of the bed. The narrower section was bolted to the end of the bed, under the gears. Seems to have worked for all these years.
It's just a couple flanges on a sleeve. No idea what it is--it seems fixed to the shaft.
The backplate is actually mounted on the spindle. Looks like they didn't want to unscrew it even though it's not stuck.
That's a pipe wrench, actually. You can see the tailstock's clamp in the lower left of that same tray.
There are several normal milling cutters, including an arbor, in this mess.
Yes, a smaller 3-jaw. See above about the backplate. There's also a very small
4-jaw in another box without jaws.
There are several of them of different sizes. I assume they're tapping heads for a DP. Big metal cylinder with a taper or shank on one end, a long arm sticking out to one side, and an old-timy tap chuck on the other. Press in on the tap chuck and it rotates with the main body, pull out and it reverses. They're very, very old.
The dovetail is 1/8" wider than that of the compound base, and it's a different angle. I figure it could be milled to the right angle, and an extra-wide gib used to take up the width. Not ideal but for something this age it would be cheaper than a corrent compound.
Thanks for the input. Only thing I can say is that it was free. The previous owners who actually used it are still in town, so I might see what else I can dig up.
No, I think one of the arms gets bolted flat against the end of the bed, and the other underneath (so that the pass on either side of the legs), to put the countershaft directly behind the spindle, and the motor mounted under the countershaft, as you say. I'm guessing the countershaft was removed from the bearing brackets so that the assembly could be removed without disconnecting the belt.
Just curious, what's the spindle thread? 2-1/4 - 8?
That shouldn't matter. They (if they are what I think) are used external to the headstock on a frame standing there. The collet is in a fitting which rotates, and which will slide backwards on the stock, but when the lever is pushed forwards, it pushes the workpiece through the stock. Of course, you need to stick with workpieces which fit through the spindle bore, and with as small a spindle boar as you have, you would need to find (or make) a collet chuck which would fit on the spindle outside of the spindle (sort of like the Bison 5C collet chucks).
O.K. No external threads? Then they are probably tool-holding collets for a mill, closed by a solid drawbar, not work-holding collets, which tend to be threaded externally, and accept a drawbar which is also hollow.
Ouch. so -- the bottom part of the compound is probably original, and the top part has been adapted (rather poorly) to it?
Yep -- and a *nice* one.
Kind of hard to visualize. The usual tailstock turret has a disc mounted at a 45 degree angle, with a bevel of the same angle on the edge, which has eight holes for tools. The holes are typically all of the same size. My Clausing has a bed turret (replaces the tailstock), and the six holes are 1" diameter. The tailstock turrets that I have seen have usually had 5/8" holes.
O.K. Make sure that it can't be used for some maintenance on the lathe.
Good -- then it fits.
For cross-feed, that pickup from the key through the sleeve goes to the gear sticking up from the apron. For longitudinal feed, it couples to the handcrank to turn it slowly. This saves the half-nuts and the threads on the leadscrew for their primary purpose -- threading. Of course, I could be wrong, but if that disk moves up or down to select one or the other, it should couple through to the handcrank and the gear which comes out of the back of the apron to engage the rack gear on the underside of the bed.
It looks it in the photos. I would put some fine sandpaper on a slab of flat stone and clean the bearing surfaces on that steady rest before they can engrave the bed too deeply. :-) The real trick will be doing the same for inside the female V in the steady -- unless it was lubricated well enough to prevent rust.
O.K. That is what matters, after all.
Perhaps to hold a grindstone? Sprinkle the ways with abrasive grit as you're sharpening a lathe tool? :-)
I thought that it was about the right size -- but it looked as though it had a lathe dog driving slot, so I decided that it was not the backplate.
O.K. As long as it is there. And is the plate which goes under the bed to perform the clamp also still present?
O.K.
Normal practice is for a 3-jaw to be smaller than the 4-jaw on a lathe. Less chance of running with the jaws too far out and hitting the carriage or the bed. :-)
O.K. If you can find jaws for it, it could be convenient for some work.
O.K. I just didn't recognize anything which looked like that. They can be useful -- though the TapMatic and Procunier are nicer. The smaller TapMatic which I have includes a torque-limiting clutch to keep the tap from snapping off -- and to give a clue when it is getting too dull to use safely.
Hmm -- build up both sides -- one with a permanent addition which you mill to the right angle, the other with the gib, which could be tapered. or you could mill that side to the proper angle too.
Or -- you could build a new compound from scratch. I once had to machine a new compound slide for my 6x16 Atlas/Craftsman after a parting tool jammed and broke out the T-slot. :-)
Looks like you have a very fine old project. Take a few days, brush the bed and legs down to bare then prime and paint, and you won't be able to stop until the whole machine is cleaned, adjusted and tuned.
The compound is well in style with the machine, is it possible that there's another bottom half in one of the boxes/buckets? (Although I'll have to agree, it looks too large for the machine, but that's from looking at machines built to todays standards.)
I've heard of machines with the feed change lever, it equates to the sliding gear used on some SB models with a quick change. IF you can find a threading chart for it, you will probably find three feeds/number of threads for each combination of change gears.
That countershaft mount is a beauty, no excuses for pulleys out of alignment.
A little fuzzy but legible. This one reads a little differently than the newer machines I'm familar with. Can you help my thick head out with decoding it? Not having the lathe's complete gear train assembled doesn't help.
Cut would refer to TPI, No to the setting of the lever on the headstock, Dr to the driving gear, there is probably a driven stud somewhere on the back, and LE to the leadscrew gear for that number of TPI. Not sure what the "Use 16 gear to compound" means, it could refer to the idler, or to changing the pitches. It would halve the ratios, or double the TPI if used as the driver gear.
I would guess that the "NO" column represents the three positions of the lever on the headstock.
Looking at the "cut" column, which I presume is the thread-per-inch, and finding three that use the same gear in the "LE" column, the ratios of the headstock lever are 1:1, 1:2 and 1:4.
The note "User 16 gear to compound" may refer to the tumbler for forward/reverse for the threading train, and a 32 tooth gear on a common bushing with the 16 tooth gear.
The LE. column is a gear mounted on the leadscrew at a guess. It looks as though the smallest vs the largest gear on that has a ratio of diameters of 2.5:1.
They seem to use the "2" position and a 64-tooth gear, instead of the alternative of the "3" position and a 32-tooth gear to get 16 TPI, probably because it is easier to get torque into the leadscrew with a larger gear.
Probably someone could take the time to calculate the proper geartrain if you told them the thread pitch of the leadscrew, and the number of teeth on the gears on the spindle and the reverse tumbler assembly.
An end-on photo of the headstock would help by showing the "harp" on which the gears mount, and show whether there is enough other stuff there to help figure things out.
A pretty good range of threads, though there are relatively uncommon threads which would take some more game playing with the extra gears, such as 27 TPI, and you seem to not have anything over 40 TPI.
Thanks, that straightens things out. I've looked at the parts and the geartrain seems fairly simple. The spindle drives one of two reverse tumbler gears which in turn drive the tranny input gear. The tranny output gear is at the hub of a banjo and drives the sliding gear. That drives the leadscrew gear. It appears that the output gear (32 tpi) is "DR." The way I got it looks like it's was last used for 20/40 tpi. I'm still a little confused as to the "use 16 gear to compound" statement. Maybe what Lennie said about doubling the tpi as the driver gear.
Sorting through the bucket 'o gears that came with this thing will be interesting. Lots of possibilities not listed in the chart. Must be 100 in the bucket.
Looks like I'll have to weld up a replacement tooth for the pulley bull gear, too.
Perhaps -- or it is a second gear in a stack to change the ratios in whatever way.
Do they all have the same hub? There should be some kind of key on the gears, so two can be locked together on a keyed bushing for speed changes, and so they can go on the end of the leadscrew as well.
If you happen to have a 100 tooth and a 127 tooth in the collection, you can probably even set up to cut metric threads, though the threading gauge will be useless for that -- you'll have to leave the half nuts engaged and reverse to get to position to cut the next pass.
Bingo. As in, with the 32 tooth gear on, and everything else set for
20 TPI, putting the 16 tooth on would reduce the feed rate to 40 TPI. Sounds like maybe an attempt to come up with a "sorta" quick change box without pissing someone elses patent lawyers off. I'd have to look at the chart again, but it's possible that it's set so for any given range of threading, one gear would give the three most common multiples used in that range.
One thing that makes the old machines so interesting, for any given function, there must have been at least 100 different ways to do it, and all of them have been patented and marketed, the designers convinced that their way was "unique and genius". They all boiled down to the same thing, keeping a given ratio between turns of the spindle to turns of the lead screw. Beyond that, it's all just avoiding stepping on someone elses toes.
The amazing thing is the amount of tooling you got with it. Not usual to see something this complete. Especially as a freebie. (Well, what you didn't pay in money, you'll pay in labor.)
It's getting less amazing the more I look at it. Of the massive quantity of gears that came with the lathe, only two fit. The rest, including a full matched set on a rod, are the wrong pitch and/or the wrong bore and/or width. I think whoever gave this machine to the guy I got it from cleaned out all the orphan tooling and parts and said they went with it.
Looks like I'll have to see what these gears _do_ fit and start dealing.
OOooooh! I LOVE orphan tooling. It's one way I get things to fit some of the older machines I have, I don't have any hopes of finding originals for them, so what ever looks like I can make fit soon fits. Just look at as a free machine with enough stuff that you can sell to pay for fixing it up. Change gearing isn't really a problem, Boston makes them yet, but they ain't free by any standards. (Which is why I'm still looking for used gearing for a #3 Barber Colman gear hobber. Gearing is their friend, and they like lots of friends.)
Sitting here bidding a job I really don't want to do, laughing at the tolerances. 3 place decimal is plus or minus .030", and it gets worse. They must want to assemble it long distance, throw the parts and have them fall into place. Material is 1018 HRS. Looks like too many hours, and I'm not really seriously in love with the idea of doing it. SOP, bid and multiply by 1.5, hope someone else gets it.
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