10K bed & low rent Kingway substitute.

About a year ago I posted a WTB for a 4' or 54" 10K bed that was worn out. I have a 4' 10K, and the bed on it is _really_ worn out. Like a .040" (or maybe worse ) wear ridge. My problem was that I just know if I tear the lathe down, it will become a never completed project. So my idea was to get a bed to plane separately to put under it when completed. Figured if I made it to that point, it would be easy to swap most of the parts and scrape as I went. Or even delay some of the finer points if necessary, like the scraping topslide & compound "later".

Well PM'r Tom Novotny responded and gave me a 54" bed. But it has a problem. It is not worn out

Still, it seemed like a good idea to inspect it and decide whether to plane it or not.
So the checks were ways parallel, and how much wear.
I've always coveted a Kingway aligner, but did not want to get stuck down that rabbit hole making one at the moment.

So I came up with these combination Vee-curvic gages.
There was a stick of quite round ground hardened shaft in the scrap drawer. The flat and curvic sides were roughed out close on the shaper. Then i dusted the chuck and the rail on a surface grinder, and dressed a wheel to do the flat side, and one with a 1/2" radius (1" dia) for the curvic side. Might be a little larger radius, I just kind of estimated it on the R & A dresser since it is not critical. The finished Vee-curvic stick was then cut up into 2 long and 1 short gages, cleaned up and de-burred.



The point of the shape is they will fit a range of inverted V's, not just "perfect 90° included angle". Not only that, but they conform to the way the ways might be laid on the machine and still provide an accurate reference surface in any orientation. In case the way is actually say 43° on one side and 47° on the other, for instance. (Square) V-blocks won't provide usefully oriented surfaces for convenient referencing in a situation like that.

Using with a parallel or bridge, for depthing. Can also be used with depth mics & indicators for other features.



With a level:



With micrometer, indicator, or other gages, to keep track of parallel:



gage shown was made a few years ago to keep track of dovetails when scraping. But it was made to be readily adaptable to other situations, as with the Vee-curvic blocks.



It looks like the bed has about .0025 total twist extreme corner to extreme corner; and about .005 sag in the front way. Maybe a little more since I was using the back way as a quick reference with the level and it would actually have some wear as well. As can be seen from the blue marks, I did lay a 4' straight edge on the relevant surfaces. I did not rig a set up so that the SE could be supported, nor check with feelers. But the general "feel" with the SE was that there is not really a lot of wear as these small lathes go. Practically new, in the scheme of what is often seen out there.

Will decide tomorrow whether to scrape or plane. There isn't much metal to remove scraping and normally that would be my choice. But the surfaces are tiny, so it is hard to balance the SE and keep _all_ the geometry aligned. Plus playing with the planer always seems like more fun.

smt

Well this is bizarre.
Last night the pictures were working perfectly. Today I can only see one.
The MWdropbox has become completely unreliable in recent months.
I'm sorry if the pictures are not showing up for others.

As a note on the work, I continued to inspect the lathe bed this morning and found that my new "Vee-curvic" gages had some variance.
I "know" better, cutting and grinding that much out of the side of a round br. It had warped a bit, so after the pieces were cut out of the 6-3/4" long bar, there was about 1.5 thousandths variation among them & one piece varied almost .001 in 2-1/4" length.

So I number stamped each on one end & took them back to the grinder, set up again, and dusted all the internal surfaces. Ideally, the individual pieces would be ground in the same position at the same setting, but that is nearly impossible to accomplish practically due to the shape. So I strung them up again in line, and did them all at once, one more time. Now they are within about .0003". So long as one always uses them in the same order and same direction, (using the numbers stamped in as the reference) the measurements will be valid.

Pictures whenever the dropbox cooperates.

smt

The secret to a King-Way is the clamps that hold everything solid and is designed to use 3 points or 6 points. So you can pick it up as a unit and sit it down as a unit and not have false readings. One simple but brilliant method my Dad incorporated to it was the radiused slot in the channel slide so you can use it on a multiple angles. We have a chapter in our manual called old vs the new. Your device for the bed is an old method that can be seen in the Connelly book and our manual. Anyone who would like a copy of the manual send me a PM with your email address.
If you were to bolt it together and use 3 points and not 4, it could be compared to the King-Way. You could title it Vee Block sled used to check lathe bed alignment.
The first pic is the HK-200 model that we sold hundreds more then the small HK-100 model then a Home made "sled" using levels with the 3- point or 5 point method. The last pic is how I use the King-Way to test narrow ways of a Myford Table. I will look for some pictures using double V's ... Rich

I see how it works and also the difficulty of making them identical. I don't see the "curvic" part. The only way I have seen the word used is couplings and gears.

Well the point was to make you look and remember, and you did.
But, you also made me look, and I had only understood "half of the equation" as it were.
I understood curvic to include a curved section that made a coupling self accomodating and self aligning, such that it distributed loads evenly.
I had not understood that this geometry includes both a convex and a concave mating surfaces. So thanks for making me look it up, I learned some stuff that will probably cause me to waste more time on some not-yet-known project in the future, sigh.

So, since it is a V shape with a flat leg and a curved leg, what short catchy term springs to your mind to describe it?

smt

Guess I was looking too hard for it. So these pieces don't participate in the measurements other than providing a repeatable "perch" on the ways? does their orientation on the ways matter?

I vote for planeing with lots of pics.

TD-

I can't tell if the pictures are showing for anyone else?
They are not, at the moment, for me. Seems to be a somewhat regular occurance with the mwdropbox these days.

The internal flat of theses gages references the "major" flat of the inverted V-way. The opposite side of the Vee which is curved, forces the block to that orientation, and compensates for inverted V's which are not a specific angle. Outside, the blocks are round. Since they were made, ground, and reground to be the same, one can level over them as a "perch" as you note, and one can measure between or outside of them to keep track of whether the ways diverge (are parallel) or not. With the ID and OD geometry, it does not matter if the inverted V's are tilted or not; or if one is different from the other.

Not only that, but once one knows the relationship to the existing V-ways, a ("small") casting (lathe bed, e.g. )can be inverted on these gages to accurately locate the casting for planing the bottom. (that is why I made 3, IOW, 3 point contact)

As noted somewhere above, there is up to 3 tenths difference among them, worst case. They were all number stamped. Their orientation on the ways matters only insofar as observing good practice for repeatability. If #1 was used with the flat on the outside of the front way, and #2 with the flat on the outside of the back way to check level or dimension at the headstock, then don't swap them around nor change the orientation at the TS end. SOP.

I've already planed the bottom and and nearly done setting up the right way.
Came up for a calculator and got side-tracked typing.
Need to grind a few tools, and then back to it.

smt

stephen thomas said:

I can't tell if the pictures are showing for anyone else?
They are not, at the moment, for me.

Click to expand...

I see 5 photos in the post at the top of this thread.

Ditto. 5 pics

Well that's good news.
Wonder why I can't see them.

Even wiped out the history and rebooted the toaster.
Hmmm.
Can't put more up, either since my box says the (mwdropbox) "this page is not available"

smt

Think I figured the dropbox issue out.
It appears that it is a service issue with my 'net provider. Access is ok after midnight (to 5AM) but they won't provide enough bandwidth to access it many days (without more $$$) Screw 'em.

Now where were we?
Here's another thing that can be done with the "Vee-curvic" gages that is not advisable with a real Kingway:

Once the distribution of error is known by using the gages, the lathe bed is inverted on top of the 3 gages. Using one as the baseline, the other 1 or 2 can be shimmed as previously determined during inspection. Then the bed is stabilized with other blocking, and the bottom planed as a reference surface.
So long as the end & one side is blocked to keep the work from sliding, it takes very little pressure to hold things on a planer due to the cutting method. These straps are barely finger tight, and the actual pressure is toward the table pin stops. Shown is SB factory planing.



twist and warp planed out:



New broadnose tooling marks



Bed now placed right side up on base, indicated to split the errors, blocked, and lightly clamped.



Using the gages to measure useful dimensions



You don't have to be able to read this, so long as I can. (there's more later)



smt

The bed had some interesting curves and twists. Nothing major, but you wonder how/why. Probably just the casting "settling".
When i indicated the bed in lengthwise, there was a deep hollow in the front vertical surface (the non-wear/non-way very front edge)
Indicating the backside vertical edge revealed a bow mirroring the front.
At first I thought "maybe the planer is out more than I already know "

So a straight edge was applied & both sides checked. Hard to hold and photo, but the results were essentially duplicated. There is about a .005" sideways bow in the casting.



Action shot: starting to plane on the Vee front sides.
Roughing bit is installed, planer is slowed down to about 35 - 40 fpm



Front sides of all the V's complete as a first operation to clean up. Next the backs will be done to clean up, then the ways will be inspected, a finishing bit installed, and the V's will be planed one side or the other to "throw them" as necessary back to original height and width relationships.



smt

Lets check how the planer is actually cutting.



Looks awful!
But the vibration marks won't catch a fingernail, they can't be felt.
The blue is not hitting like it might from a new planer, but this is probably within .002 or so of flat.

Time to review tool geometry, and give a plug for my sponsors
A while back, John Oder sent me a handful of 3/4" square NOS Pratt & Whitney CPM tool bits.
These have proven marvelous and long running for broadnosing the surface of the planer table. Just really fantastic steel. It is tough and does not chip.
So I ground one of the bits into a double end stick with opposite 45° on each end. My plan was to not have to move (swivel) the toolslide so that it would be relatively easy to go back to baseline by merely reversing the bit, and perhaps loosening and nudging the clapper box around. This worked quite well, and the P & W steel was just ideal in terms of the razor edge it would attain, and then hold it without chipping.

More recently, in thinking about this job, I posted a note on PM requesting info on positive rake 3/4" or 1" edge triangular inserts. My idea was to make a stick tool that took 2 inserts, so the tool could be used toward either side. The critical element of my plan was to make the tool body to hold the inserts at a negative angle, but with the positive edge providing a shearing cut. Well you guessed it, the next time I went to check the mail, a box from Ray Behner had arrived full of inserts!

As can be seen, however, I'm trying not to get bogged down in this project, and mostly just "get it out the door" even if it's for my own shop.
So I debated and sketched while running other ops, and finally decided that beautiful as the idea might be at some point, the CPM steel was working so well and was so simple to grind and use, that there was no need to abandon it for carbide for this lathe bed. Ray's support is much appreciated, and I'll make a similar tool at some point in the future. Those inserts are compelling me.

But the shear cutting tool was not an idea I could abandon. So the short end of a Crucible CPM M4 was ground as I had envisioned the cutting edge to present for a finishing tool.

Face of both tools; arrows point to working edge:



backside hollow grind on both tools.



Perhaps difficult to visualize it in this photo due to perspective, but the finishing tool has a rather acute sharpness angle for a metal working tool.



Shear cutting with the finishing tool.



smt

I'm curious, why did you plane the bottom feet ? I used to set the bed down on a blued surface plate and if they were good, leave them alone. If they were a tad bit out i would scrape them and set the down on the bed to get the new machine datum back.. It seems odd you would go off the worn ways to re-machine factory planned surface? What am I missing here? Rich

I'm curious, why did you plane the bottom feet ? I used to set the bed down on a blued surface plate and if they were good, leave them alone. If they were a tad bit out i would scrape them and set the down on the bed to get the new machine datum back.. It seems odd you would go off the worn ways to re-machine factory planned surface? What am I missing here? Rich

Click to expand...

1.) the bed had some twist in it.
2 the feet were not co-planar from (apparently) casting warping
3.) the factory SB planing was quite rough.

This was very quick and simple.
If you actually read my description, I did not "use the worn ways for reference"

I used the "Vee-curvic gages, with the lathe already inspected and measured to them as a fool-proof, 3 point reference. (the lathe is setting upside down on those 3 gages/points, set to known height). Since I was happy with the 2 at the headstock end (6" in from the end) as being on factory scraped surfaces "close enough" to where I wanted the casting to come out; the only thing to do was establish a point about a 1' in from the TS end while inspecting, and determine how much to shim it. A .004" thick shim was the correct number. This put the ways to the planer bed, at the same datum as the factory plane (considering splitting some errors for twist).

This took less time than 3 trips to the surface plate to scrape the pads, especially since I don't have a suface plate larger than 24 x 36. Now the bed could be put down flat on the planer bed and know it was back to factory reference, and as good as it was going to get for planing, given some wear in my machine. I doubt there was a full hour, probably about 1/2 hour, in set-up & broad nosing the underside pads. I did not actually measure, but guess would be that it required .005" - .007" to clean up and straighten.

I did intentionally bend the bed a little when putting it down on the planer bed.
I had established, using that straight edge you sold me a dozen or 15 years ago that the planer bed had about a .001" hump in the best area, where I wanted to plane the lathe bed.
When the bottom of the SB bed was planed, and turned over, it indicated the same thing: It could be spun on the middle pads. The planer bed had been planed last week, the SB bed was planed over a given area, so the error was double. With a piece of .004 thck typing paper (the good stuff) under each end, a .002 feeler was a very snug fit undeer the center pads. So apparently the planer was cutting about a .001" hump in 48"to 54"(lenght of lathe) in that area.

So, when setting up, I decided to try an experiment. I used .004" typing paper under each end, and found some cheap thinner stuff that was just over .003" thick, to put under the middle. (remember, free space is .002") so basically I was bending the middle of the lathe bed up, .001" to (we shall see ) compensate for the .001 hump the planer will put in it.

I did the planing on Sunday and a little bit yesterday. Have to do the undersides later today, so the lathe is still on the planer bed. I can't post pictures until after midnight, due to my 'net service provider and can't even see if anything showed up today. Will post more pictures when it's possible.

smt

I was just curious and i had read what you did with your gage. You know i used to have 2 planners over the years and have planned lathe beds before. I would have done it a bit differently is all. Not trying to argue with you just I would have done it another way. I used to have a Clevland planner like the one Charles told everyone about that is in Milwaukee. It now is being used by A&D Machine rebuilders in WI. A & D Machine Tool Rebuilding, Inc. | Machine Tool Rebuilders, Way Machining and Hand Scraping, Turcite and Rulon Application
He mounted a Bridgeport head on it and also now has a larger machine as shown in his web-page. The 8' straight-edge he is showing on the lathe bed used to be mine too.

Rich

Richard,

I'm sorry I was crabby. Once again could not see the photos, and am aggravated at my internet service provider. I've always appreciated your input and support. I am also genuinely curious about your different method, to set up on a planer. Planing the bottom seems so simple on this size, and is most likely where the factory started, too, from what I have understood. Either way, happy to hear new options. There's always a different way, and if it does not work for me this time it may be the perfect solution in the future!

Interesting that you sold your 8' SE to "A & D, Inc"
Just by coincidence, I sold my 8' Challenge to PM'r "AMDinc"
Could not face lifting it anymore.

After planing all the inverted V's and verifying with the little gages that they were still in the same relationship, it was time for an easy one, the TS flat. In this photo a cut has already been taken. The depth mic is being used to see how much more to take off. It has been determined (in this photo) that there is still .007" reduction necessary. So a planer gage and a .007" feeler are ready for use.



Using a thick parallel (for stability) the planer gage is set with the .007" feeler, the full amount of depth to be taken.



I then used a .004" feeler to set the toolslide. (theoretically .007 - .004 = .003" DOC) This is because planer slides are darn devilish to set because the lost motion is in the wrong direction. So letting the tool slide hang loose it was brought back up until .004" would just fit under it, then locked and the cut taken to see what actually happened. Measuring again after the cut showed things were on the right track, and I took off another .002 cut on the dial. It actually cut about .0025" letting it run a few strokes at the same setting, so I quit there. This flat was not broadnosed, so it needs a little more margin to clean up. The planing is a little more accurate cutting across in small steps, but the finish is not as good.

Next step could probably have been eliminated. But I hate quitting on something that is all set up and finding out later there was good reason to do it when it is easy. This is cleaning up the underside flats, where things like the TS clamp, and the steady rest clamp fasten. The tool was set flat to the ways by means of the gages, parallels, and a couple 123 blocks screwed together for the offset.



Starting the cut:





The air lifter picks the tool up over top of the casting, for the back stroke.



smt

The front and back underside ledges do not need to be any specific measurement. They just need to be cleaned up, and parallel to the top ways.

Here, the bigger planer tool holder for 3/4" bits is back in, and one of the P & W bits has been sharpened on both sides to use for each side of the lathe bed.
Setting to gages again so it can be fed straight up for finish shaving the cut.



Doing the front ledge next. The tool has already been set square/parallel across. Checking the height to begin cutting, and verifying the tool will clear the table clamps.



My cheat sheet & inspection report.
(many of the measurements are in process tallies. For instance the set of measurements along the ways, to the outside underside ledges that showed enough variance to make it sensible to plane them while everything was set up)



I also topped the Vee's but found out (compared to the saddle) that I did not take enough off. But that task is trivial, and it will be nicer looking to get some remaining dings out. Also, the areas between ways could be reduced to give more time until the saddle starts dragging for the next rebuild. About another hour, all told. Maybe less if there are suitable tools (cutters) in the drawer ready to go for the spaces between the ways & I don't get too bogged down dithering whether to take off .010, or .015

Then it can be unbolted to see if the springing idea worked, and how much to scrape where.

smt

Did not have much time to work on this, but finished planing the tops of the V's and ploughed some out between them to give room for the saddle to settle over time when it wears again.

Also started to set up to plane the leadscrew slot.
Too rushed for inspection of the bed, but took some photos before it gets dirty and scraped up.
It's really difficult to get clear photos of the ways, taking the whole thing in. Bright pictures are spoiled by glaring light reflections, and low light to get rid of glare does not bring up enough detail. Will try some smaller sections another day, to show more detail.





smt

Fantastic right up. thank you so much,

Could any one explain again, what makes the KingWay clamps to special? I don't quite follow.