I like the KWAT, and I'll probably make one, but it is not the right tool for this project. The sequence I'm using for this project demands that I establish 2 datum planes that are parallel to each other, and from there I can I can establish the other 2 planes. The first plane I established was the inside flat way, using the methods previously described. If there are any inaccuracies in the flat way as I approach the finish, the only way I can find them is by using the MPL on blocks, and comparing readings. Now, keep in mind that I had a high section starting at station 6, approx., and going to station 8, the end of the bed, of approx .00025". 2-1/2 tenths is not much, and it's within the bed tolerances. I could compensate for this when I got to that area on the V way, so I thought.
When I got to the finishing stages on the V way, I was having problems as previously described with the TS end of the bed. I spent most of Friday afternoon chasing this problem, but I kept getting readings were not very consistent. I still had a high section on the V way between stations 3 and 8, although 3-6 were rising and falling, but overall the tendency was to rise. To add to the confusion was the use of the shim on the V block. Ok, I'm setting up the KWAT to see what it shows, it has to be better than what I was doing. Unfortunately, the KWAT basically said I was done, and I knew this wasn't correct.
Saturday morning, I decided to re-spot the flat way from stations 2-8, and it spotted all the way with a very minor gap between 6 and 7. The gap was a leftover from the 1st scraping cycles on the bed, my straight edge is 48" long, or else I had differing amounts of blueing on the SE. I know there is a .00025" high section from 6-1/2- 8, about 11", from the MPL readings. The MPL is 15" long, and the left end was on the 1st 4' scraped section. I decided to do some very careful scraping on that section and get rid of the rise. I was successful, and got the rise down to practically 0, according to the MPL.
With the elimination of the high section, and the regrind of the flat block, I was finally able to get some dependable point-to-point transverse readings with the MPL. The KWAT is very capable of this, with one caveat, and this must be considered; it measures on a triangular base, and one leg will never get to the end of the bed.
There are definitely advantages to the KWAT, and I will use it in subsequent operations, but IMO it is not the tool for this application. There are certain advantages to the MPL that the KWAT doesn't have. I can use the MPL directly on the flat ways, or on blocks. I can shorten or lengthen the measuring base at will, by moving the blocks closer together, or interposing a long parallel on top of the blocks, none of which can be done with the KWAT.
A word about MPL's:
The selection of a MPL is very important for this type of project, but the cost is secondary. There are imported MPL's, with grooved bases, at much lower prices. IMO, the grooved base is a major disadvantage contributing to instabilty when used in the manner I'm using it. I haven't seen every domestic MPL made, but every one I have seen has a solid base. I bought mine, new, in 1983 for the princely sum of 254.00, and have never regretted the expenditure. I know the prices are approx 600.00(new) now, and I would definitely be looking on "ebay". I didn't have any other option in '83, there are options today, CHOOSE WISELY.
Below are 2 pictures of the leveling charts. The first is the chart using the readings from the MPL. What I'm looking for is consistency in the readings. There are 3 sets of readings, 1 each for of the inside ways and then the transverse readings at each bed station. In case you can't read some my "chicken scratch" the numbers are in ten thousandths; ie 2=.0002, 10=.0010, etc.. There where other readings not recorded, especially, where I noticed something unusual, and everthing seems to be in agreement. Overall, I'm fairly satisfied with the results, although I'll study these numbers, especially the numbers for the headstock area, 0-2, on the V way. I'm not to concerned about 2 through 3-1/2, the tailstock will never get there, and the 7-8 section.
On the transverse readings, the flat way is regarded as the reference surface.
The second chart is of the readings using the KWAT at the bed stations that could be measured. The ends of the flat way could not be used, due to the construction of the tool. I also noticed that the tool seems to be rather delicate, as evidenced by the #7 reading. I don't know if accidently hit it, or if moved of its own accord when I relocated the tool on the bed. I do know the vials will shift under very easily, at least on this particular tool, which may be due to the vial mounts being loose. I'll have to investigate.
After studying the charts off and on for a few days, I decided that things could be better. The problem was deciding where to start, a little off here is going to affect something there. I didn't want to remove more than necessary, because that causes more problems than it solves.
I cleaned off the straight edge and applied a very light coating of blueing and spotted all three surfaces, and the answer(s) was/were "staring me in the face". From the charts, I know that the ends of the flat way are high, but I couldn't tell if one or both faces of the V way was causing problems. The spottings showed the expected distribution on the flat way, the spotting on the inside face of the V way showed a very good distribution, but the outside face was a different story, and basically confirmed the longitudinal level readings. The course of action was determined; correct the flat way first then work on the outside face, second. Level checks, the most time consuming aspect of this project, would have to be run after every 1 or 2 cycles.
When I quit yesterday, the flat way was basically reading a +2-1/2 across the board, and the V way was reading +2-1/2 from stations 0-3, and the differences have been halved for 3-8, and the transverse checks have confirmed this. I won't need much more time to finish this part of the project.
The shaping/planing sled design has been roughed out, and construction has started.
Finished up the inside ways today, and the results are much better than the previous charts show. All the numbers are .XXXX, and are the estimated actual bubble position.
Making some progress on the sled. In the picture below, there is the base and the cross slide, the turret lathe slide tool goes in the 1-3/4" hole. There is still some work to be done, mill the slot for the cross slide, drilland bore a hole for the nut, plus a few other holes. The Multifil 426 way material has to epoxied to the slides and scraped, if you look closely I'm checking the base with some small strips of the Multifil in the corners, just to make sure it's right. I've got the level on the base to see bad things are; a little scraping of the Multifil should take of the alignments.
The base is 1-1/4" X 6-5/8" X 15" HRS to give you idea of scale.
Very interesting. Do you plan to use the sled to finish up the ways on the 10EE?
I plan on using the sled as a shaping/planing tool, using ceramic inserts to remove the bulk of the excess material, and then finish scrape. If this works, I've had this idea brewing for quite awhile, it will greatly reduce the amount of scraping. The biggest obstacle are the inserts, they are fragile, at least the ones I use on one of my products are. It may be the geometry has to be changed. I just don't know, and it's going to take some experimentation.
I assume the slide tool does the actual shaping/planing and the sled acts as the base? I guess this sled will only work on 10EEs?
When you get a chance, could you post a photo or two of the slide tool?
The sled will only work on this EE, it would most likely have to be modified for other EE's.
Check my post of 12-18, in this topic, about the slide tool.
Multifil 426 Tape
Garlock Multifil 426 Tape is a teflon material that appears to have bronze dispersed through it. One side is chemically etched for the bonding agent, in my case I'm using 3 M Scotch-Weld 2216 B/A Gray epoxy adhesive. It is a way strip bearing material that greatly reduces the friction between 2 surfaces. The friction reduction is even more-so with the use of lubricants. I use it in the reconditioning process to regain the height loss from wear and scraping on the carriage. I have also used it in the refitting of the cross slide. Don't make the mistake I made early on, and use it on the bottom of the tailstock, they become very hard to lock in place.
I am attaching a link to Garlock's website. Turcite and Rulon can also be used, but I have no experience with thosoe products.
Below are some pictures of the sled. The first is of the surfaces prepped for the Multifil. Notice on the flat slide the additional scratches/gouges in the surface for increased roughness for the epoxy. The scratches are also in the V slide. The Multifil strips have been marked, the white dot, to identify the etched side. The etched side will wet with water.
The second picture is an end view of the sled after the Multifil has been epoxied in the V and flat slides. The wax paper acts as a releae agent between the weighted clamps and the Multifil. I manage to get the epoxy everywhere. I had the wood blocks made for my other EE when I did the same thing several years ago.
The third picture is a front view, and underneath all that mess, is the sled.
This same process will be repeated when I get to the carriage.
What is the minimal Multifil thickness one can use for rebuilding the way? It seems to be a little too much trouble if you have to mill the saddle to get that thickness requirement before you can glue the Multifil strips on. BTW, Harry, thanks for posting. This certainly will serve as a key reference for the Monarch forum members.
Multifil is available in .015-.125 thicknesses. I have .030" which has served all the applications I have encountered, and I have tried to work with that in mind. This stuff is pricey and only available in full rolls, 12" X 120" IIRC. I don't know what the other types are available in, although I seem to recall that Turcite can be obtained in needed quantities from one vendor.
Keep in mind that machining some base material off is a whole lot easier than scraping it off. The amount of metal machined off should be determined before hand, and consideration should be made for the epoxy thickness and scraping allowance when using Multifil, or any of these materials.
The main reason for using the Multifil is to biuld up the height of the carriage, so that the leadscrew and other alignments can be maintained. I'm really not interested in relocating brackets and gearboxes.
I'm using it on the sled because of the ease of scraping, but mostly because of its coefficient of friction. This stuff is like "greased lightning", compared to metal on metal contact.
I had to do some calculations when I machined the sled to account for the above, and I'll have to do the same when I get to the carriage.
Multifil scrapes very easily. I do it using hand scrapers, the Biax is to hard to control, IMO, on this stuff. I learned that lesson when I scraped the CK's saddle, and that took about seconds.
Russ Kepler did an excellent post on the application of Moglice, and it's a "sticky" here. One of the advantages of Moglice, that I can see, is that you are basically done with scraping after the Moglice has cured. One of the disadvantages is all the front end work that has to be done. I think it's a draw, IMO. I don't know how the financial costs compare, but for a couple hundred dollars, I've done several machines and still have enough left over for several more.
This seems like a dumb question to me.... but here goes. What is the scraping/planing sled going to do? I have read the whole thread and I thought you were nearing completion of the scraping process? It seems like everything is now flat and in alignment?
Sorry for being so thick.
Only the inside ways are completed. The sled is made to fit the inside ways. I can mount a cutting tool on it to plane/shape the outside ways. When the sled is completed, I'll post some pictures, and this will all fall into place.
I am nowhere near being finished; there is still the headstock, tailstock, carriage and cross slide assemblies to work on.
The sled has been finished and tested. It does what it's supposed to do, but it took some trial and error. One thing I re-learned, is that ceramic inserts don't take to well to being dragged backward, they'll chip the cutting edge faster than a heartbeat. Every now and then I need a reminder. I tried a carbide insert with the same results, then I tried a brazed carbide tool bit. That worked reasonably well, until I decided to grind a broader nose radius with a bit of a wiper edge. After thinking about this for awhile, I decided the easiest thing to do was set the stop on the slide tool, and back the tool off after the stroke was completed and push the sled back to the starting point, move it over and reset the tool for the next cut. This was successful, and will be the procedure I'll use. I considered a clapper arrangement, but decided that it would take up to much space on the end of the slide tool. The rear flat way took about 30 minutes, or less, to do, removing about .002". Then I'll start the sequence again after adjusting the stop, for the next pass.
There are some improvements/changes that need to be made. I need to put some wipers on the sled, I'll borrow the tailstack's wiper holders for this, and I need to add the oil cups. I think there may be a couple other improvements necessary, but I'll have to get a firm grasp on them before commenting.
Some more pictures;
Bottom of the sled with the Multifil scraped. Notice the light gray strip on the right side of the flat slide. The Multifil is extremely in this area, and most likely for the entire flat slide, due to a calculating error on my part. I discovered this yesterday, and thought I was going to have to remove the Multifil, mill the edge deeper, and epoxy new Multifil and rescrape, before I did that I milled off approx .0045" and rescraped, and this is the result. Not the best situation, but this is a one use tool.
The reddish hue in the V slide is the spotting medium. Red is easier to see on a black background than blue.
The rest of the parts for the sled; the cross slide with the slide tool, the cross feed nut and screw, clamps, and the tool block for the slide tool. The screw is 1/2-20 allthread and the nut is steel. The cross slide and nut/screw assembly is made to be reversed in the base as a unit. The nut drops into the hole in the base. It's a nice slip fit, with very little shake. The tool holder is a 5/8 shank for 3XX TPG inserts.
The next 2 pictures are of the sled assembled. The second picture shows the flat way partially planed.
Continued in the next post.
Continued from the previous post;
Indicating the outer ways.
Outer ways chart, before planing started. After scraping the inner ways, the outer ways don't look as bad as I first thought.
Another picture of the flat way, you can barely make out the tool marks. They scrape out, I've already checked, but I think the cross feed is going to be reduced a little to reduce the peaks and valleys.
Looks like a great tool. What is holding the sled down ? Looks like it is manually operated by pushing it from one end to the other? What do you think about mounting a grinder instead? Very inspiring indeed.
I push it up and down the bed. There is nothing, except the weight of the tool, holding it down, which is one of the issues I have. It almost hit the floor this afternoon, when I pushed a bit too energetically as it came out of the cut and tipped.
I have thought about putting a chain drive on, but after using it today, I think I'm going to abandon the idea. There are a few problems to overcome, and by the time I get them solved, I'll be done with this part. If the scraping hardened iron didn't take so long, I wouldn't have gone to the trouble to build the sled. The little I took off in 30 minutes is about 8 hours scraping, and that makes the sled worthwhile.
I have several thoughts about grinding in my situation, most of them negative. I have several machines in close proximity and containing the dust and grit is a real problem, and it really should be a wet operation, which presents its own set of issues. I also recall reading in one of older posts on PM about grinding cast iron, mainly the need of a rather large diameter wheel.
One of the members here and I had a conversation when I concocted this idea, and he mentioned a toolpost grinder, and I immediately thought of the above and basically ruled it out.
I have thought about a grinding apparatus for lathe beds, but by the time the design work is done and the cost of materials is determined, I think sending it out to people already set up with proper machines would be more cost effective.
The sled has been a real learning experience.
I tried to fit wipers to the sled, but that proved a no go. I used felt, and as long as the wiper was entirely contained on the bed they worked, but by necessity the ends of the sled have to over travel the ends of the bed. The wipers were mounted with a bit of compression, and once the sled end passed the end of the bed, the wipers expanded making it very difficult to get that end back on the bed without breaking the wiper holders or the ceramic insert. They basically acted as a stop, so I abandoned that idea.
I added oilers, but had so-so results.
In the end I used the sled without wipers and it seemed to be better operating dry than with oil. Fortunately it is a one use tool, as the Multifil will most likely have to be replaced due to some chips getting underneath and doing their thing.
I have finished the rear flat way and scraped it in. The results from sled were mixed. I wasn't satisfied with the surface finish, most likely due to amount of cross feed for each stroke. There was no way I was going to put a straight edge on that surface, before I went over it with the Biax and a stone. I was also disappointed with the flatness, the sled seemed to be following the contour, although flattening it out considerably. There more to scrape than I was expecting, but a lot less than no sled. This operation had to rethought before I got to the front V way.
There was/is a complication that I'm to blame for, which I discovered by a casual glance at the level's cross vial, which happened to be out by half a bubble. I got it down to about a 1/8 of the bubble, or less. Not the best situation but not a killer either, just makes transverse leveling a bit more touchy. If this was on a lathe without 3 point leveling, this would more touchy, and really should be corrected. The carriage will be scraped to match, so I'm not worried about this aspect. The root of the problem is the cross slide's slot/way in the base, compounded by the fitting of the Multifil. I just didn't consider this, and unintended consequences reared its ugly head.
The sled operations on the front V way were revised to reflect what I learned from the rear flat way. The cross feed amount has been/was reduced to .005" from .008-.012", the depth of cut stayed the same at .005", with the final pass reduced to .002", and the finish is very nice, with the feed lines considerably reduced. I ran and indicator on the shaped/planed inside face of the V way and it was within .001". The outside face has had one pass completed, but play time is over for a few days.
A few pictures.
Spotting the progress in the attempt to correct the transverse alignment problem. These pictures are 2 separate spottings.
Indicating the slide tool to the "good" section of the inside face of the front V way. Same set up was used for the outside face. Actually in this picture I'm measuring the amount of wear in the face, which is approx .012". The same set-up was used to indicate the slide tool on the end of the way.
Set up for the travel indicator for the sled's cross slide.
Continued in the next post.
The wear on the inside face had valleys on each side of the shiny ridge. The top half was about .012" deep and the bottom half was about .008" deep. The ridge originally started at station 2 and ran to station 6.
The chart for the rear way. I ran the level readings for the inside ways for verification purposes on the rear flat way. The only reason I can think of for the differences from the previous chart would be temperature differences between the 2 days.
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