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expressline99

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#1
I'm reading the Connelly book and currently reading about templates frequently used and made. Are v templates (male and female) available? I assume made similar to v blocks but with different angles? If so what are they called in current terms? I can't seem to locate any using "v templates" Since this are used to ensure there isn't tilt occurring from uneven wear and there are 2 on my Logan bed... I thought I would look into it. Ideas suggestions?


Paul
 

4gsr

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The vee templates Connelly talks about are all ways special made to each machine tool manufactures needs. Most machine tool manufactures in the days made their own. They poured the castings in their own foundry, seasoned the castings, machined them, stress relieved them, finish machined them, last scraped them straight.
I have a couple of dovetail templates made by a long gone lathe manufacture I got ahold of many years ago. vee templates and or straight edges were not common. You pretty much have to make your own. These templates were only made about 12" to 24" long. They were not made the length of a lathe bed. They were only made to control the form of the vee so they would be consistent from machine to machine.
 

Bob Korves

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Hi Paul. The V ways of machines need to fit each other when new, and are machined to fit, and sometimes scraped to match. Specific angles are called for, a manufacturing neceessity. In reconditioning a machine, specific angles matter not at all, the mating parts just need to fit each other. If the dovetail is nominally 55 degrees, and we scrape both surfaces in at 55.437 degrees to match, nothing is lost, so long as the geometry of the total machine is correct and the mating surfaces match each other with full bearing.
 

expressline99

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Thanks, Ken

Hi Paul. The V ways of machines need to fit each other when new, and are machined to fit, and sometimes scraped to match. Specific angles are called for, a manufacturing necessity. In reconditioning a machine, specific angles matter not at all, the mating parts just need to fit each other. If the dovetail is nominally 55 degrees, and we scrape both surfaces in at 55.437 degrees to match, nothing is lost, so long as the geometry of the total machine is correct and the mating surfaces match each other with full bearing.
Hi Bob, the angles make total sense said that way. ..I keep reading and trying to understand it. It's still difficult for me to visualize how to measure the parallelism, tilt, square...etc etc.
Where to reference from is my main issue on the lathe. I'm starting to get how it would work on a mill. However, working compound down on a lathe still mixes me up. I really need a lesson on Metrology.

Paul
 

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Paul,

Trying to establish reference planes to work from are not that difficult to do in your case with your Logan lathe bed. Most all surfaces are machined/planed in the same setup when done. If you are trying to determine how much wear you have the bed ways, you have to work off the unworn surfaces of the bed. These surfaces are usually the sides of the bed, and the surfaces between the vee's and flats. From these surfaces and the use of fixturing that rides on these unworn surfaces, you can measure, with dial indicators, the wear on the vee's and flats normally used for the saddle/carriage and tailstock. The only other way to measure this is to put the bed up on a planer or surface grinder or large CNC mill and measure. Now, for making the vee's and flats, flat and straight again. You either re-machine these surfaces on a machine capable of doing so or using a straight edge of known straightness, scrap and make flat again.
One thing to remember, when you re-scrap or machine the ways, the saddle has to be re-fitted to the bed ways. And depending how much material is removed, may have an effect on the lead screw alignment with the carriage, too.
 

expressline99

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Paul,

Trying to establish reference planes to work from are not that difficult to do in your case with your Logan lathe bed. Most all surfaces are machined/planed in the same setup when done. If you are trying to determine how much wear you have the bed ways, you have to work off the unworn surfaces of the bed. These surfaces are usually the sides of the bed, and the surfaces between the vee's and flats. From these surfaces and the use of fixturing that rides on these unworn surfaces, you can measure, with dial indicators, the wear on the vee's and flats normally used for the saddle/carriage and tailstock. The only other way to measure this is to put the bed up on a planer or surface grinder or large CNC mill and measure. Now, for making the vee's and flats, flat and straight again. You either re-machine these surfaces on a machine capable of doing so or using a straight edge of known straightness, scrap and make flat again.
One thing to remember, when you re-scrap or machine the ways, the saddle has to be re-fitted to the bed ways. And depending how much material is removed, may have an effect on the lead screw alignment with the carriage, too.
I went out and took a look at this on the lathe. I can see now there are 2 machined surfaces on each side of the ways that can be used. Those sides jumped right out at me this time. Seemed to me any machined edge would have been a bearing spot. I think that's why it never occurred to me. Simple when looking at it now. Both inner and outer flats have zero contact with any sliding member. But they need some non-abrasive cleaning as there is over spray from painting and various material stuck to them.

Paul
 

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#7
Most machinery has reference surfaces built in, and often it is intentional. You are not the first one who needed to measure their lathe for wear, not by a long shot. At least you have some input on how to do it correctly. If you want to make some templates to check out the V-ways, you will need to make them to fit the ways as they originally would have been when new. There is usually negligible wear at the tailstock end of the bed, and also very close to the headstock to use as patterns. On some lathes, extended ways support the headstock in the correct position, and those surfaces should stay pristine, but require removing the headstock to get to them, not exactly a trivial task... The ways near the tailstock end are usually adequate for the purpose. The templates need to fit the factory ways, not your worn ones, and also need to have reference surfaces, typically the flat tops or the bars, that are parallel to the V-ways and also the same distance from the V-ways. I think I remember Connelly covering making templates pretty well in the book, except he made it sound easy, and it no doubt was for him. I really recommend that you read that entire book, cover to cover, and get some serious scraping practice and training, before attempting any portion of a reconditioning to your lathe. There are many nuances that can and will influence the final results as well as the overall difficulty of the project. Make sure you pretty much understand the entire project and the work flow sequence before starting any part of the job. If you start with fitting the wrong parts in the wrong way, you can end up with major metal removal required further down the line, or starting over at the beginning... BYW, I am by no means any kind of expert at this, far from it, but I have read and studied it pretty well, and do have some limited experience with scraping and with adjusting the fits of machine members.
 

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#8
Paul,

Here is a fixture I made to check the alignment of my Lodge & Shipley lathe I used to have. If you notice, the rollers, in my case ball bearings, rode on the top of the ways. On this lathe, the top of the ways and the side of the ways is what I located off of. They had no detectable wear.

I also used this fixture to regrind the ways with. And by no means I encourage anyone to use this method to recondition the ways with. I done it just to prove it can be done and I knew what I was doing, too!
 

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Bob Korves

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#9
I should have made it clear in my post above that the templates I was describing would not just be for checking the ways for wear, but also for critically checking the ways as work proceeds during reconditioning. The templates would need to be joined together solidly into a single fixture for measuring both ways at once, to make sure the V's are the correct distance apart and vertically parallel as well, while forming the correct shapes and heights. Simpler templates can be used for just checking wear.
 

expressline99

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Most machinery has reference surfaces built in, and often it is intentional. You are not the first one who needed to measure their lathe for wear, not by a long shot. At least you have some input on how to do it correctly. If you want to make some templates to check out the V-ways, you will need to make them to fit the ways as they originally would have been when new. There is usually negligible wear at the tailstock end of the bed, and also very close to the headstock to use as patterns. On some lathes, extended ways support the headstock in the correct position, and those surfaces should stay pristine, but require removing the headstock to get to them, not exactly a trivial task... The ways near the tailstock end are usually adequate for the purpose. The templates need to fit the factory ways, not your worn ones, and also need to have reference surfaces, typically the flat tops or the bars, that are parallel to the V-ways and also the same distance from the V-ways. I think I remember Connelly covering making templates pretty well in the book, except he made it sound easy, and it no doubt was for him. I really recommend that you read that entire book, cover to cover, and get some serious scraping practice and training, before attempting any portion of a reconditioning to your lathe. There are many nuances that can and will influence the final results as well as the overall difficulty of the project. Make sure you pretty much understand the entire project and the work flow sequence before starting any part of the job. If you start with fitting the wrong parts in the wrong way, you can end up with major metal removal required further down the line, or starting over at the beginning... BYW, I am by no means any kind of expert at this, far from it, but I have read and studied it pretty well, and do have some limited experience with scraping and with adjusting the fits of machine members.
I don't anticipating starting work until I am done reading it and have more practice with you and the guys first. My mind spins in a lot of directions. So all my questions are advance research. As well, I won't practice on my lathe. I think I will buy extra parts for it to practice on. Maybe an extra compound and extra cross slide that would fit?
 

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I'm getting a visual on the direction you are going here and what I'm proposing is to only get you close in seeing how much work you need to do. This is only a ballpark or basic start, and maybe you don't need to do as much as you think.

I get lots of folks walking through the door with products to bend and I need to determine the angle(s). If it's bent then it has a radius and if it's rollformed it usually has even more radius. An example might be a roof flashing for a penetration through a metal building roof panel. There are usually some constants here, like center-center of the ribs, height of the ribs etc and I have to take into account any stretch or distortion. My reference here are ribs that are truncated cones, or in your case, the Vee's. With that said; I begin with getting an approximate angle using the flat of the panel up the side of the rib. I take the centers of the ribs, the base dimension of the ribs, the flat (truncated) across the top and with a little math determine what the angles are, what the stretchout of the flat piece should be (hopefully).

Now to your project; After the preliminary task of getting close, I shear, notch, and spotweld a template that fits the panel shape before I shear and bend the real thing. I think you can see an end view of a one piece template that fits the bed as Bob explained, and if you need any help with coming up with a template just PM me. Many times I take strips of metal (16 ga.) and vicegrip them together as I work through the angles, by placing the pieces against the shape I'm measuring or attempting to determine an angle. If you get a good fit across the unworn section of the bed, then you will see the daylight on the worn sections.

As I stated, this is to give you an idea of what's on the road ahead, before you go to Bob's #9 post. Okay, and I see I missed Ken's attachment for the fixture, and in essence that's my idea but at a basic level to start.
 

expressline99

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I'm getting a visual on the direction you are going here and what I'm proposing is to only get you close in seeing how much work you need to do. This is only a ballpark or basic start, and maybe you don't need to do as much as you think.

I get lots of folks walking through the door with products to bend and I need to determine the angle(s). If it's bent then it has a radius and if it's rollformed it usually has even more radius. An example might be a roof flashing for a penetration through a metal building roof panel. There are usually some constants here, like center-center of the ribs, height of the ribs etc and I have to take into account any stretch or distortion. My reference here are ribs that are truncated cones, or in your case, the Vee's. With that said; I begin with getting an approximate angle using the flat of the panel up the side of the rib. I take the centers of the ribs, the base dimension of the ribs, the flat (truncated) across the top and with a little math determine what the angles are, what the stretchout of the flat piece should be (hopefully).

Now to your project; After the preliminary task of getting close, I shear, notch, and spotweld a template that fits the panel shape before I shear and bend the real thing. I think you can see an end view of a one piece template that fits the bed as Bob explained, and if you need any help with coming up with a template just PM me. Many times I take strips of metal (16 ga.) and vicegrip them together as I work through the angles, by placing the pieces against the shape I'm measuring or attempting to determine an angle. If you get a good fit across the unworn section of the bed, then you will see the daylight on the worn sections.

As I stated, this is to give you an idea of what's on the road ahead, before you go to Bob's #9 post. Okay, and I see I missed Ken's attachment for the fixture, and in essence that's my idea but at a basic level to start.
I've got a lot of thought to figure this all out. All three of you are so far out ahead of my comprehension. But the roof ribs and flashing make sense to me.

So in order to get the correct dimensions am I to measure the vee's bottom and top. This being at the tail stock end where the wear should be almost non-existent?
What I don't understand is that the beds on these were supposed to be hand scraped. I can't seen any scraping marks. Not one.

I really have to look at Ken's drawing again. I don't quite understand how to get a reference from a rolling jig if the non-bearing machined surfaces are on the vertical sides? Assuming the machine is working position horizontally and correctly leveled. Wouldn't a rolling jig like that end up riding on the bearing surfaces and throw off the measurements of wear? I'm guessing my thought process isn't complete due to lack of experience.
 

Bob Korves

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#13
I do not think sheet metal shapes would do a very good job of mapping the wear on a lathe bed that is measured in thousandths. But, Russ is a pro, and I could be wrong. Ken's setup was an experiment designed for grinding a lathe bed with a normally handheld grinder mounted to a trolley, which was also used to map the existing wear and the progress.

Bed ways become swaybacked typically from use, with most work done near the chuck and therefore more wear in that area where the saddle typically moves back and forth a lot. The ways also wear sideways from side loading from tool to work loading. Before we start removing metal, we need a map of where things are at the start so we can make plans to remove the minimum amount of metal to get the desired results. We also need to test the progress of the work as it progresses, and finally we need to be able to know when we have accomplished the repairs to within the required tolerances. We make jigs and templates to assist with those measurements, which cannot be done with a ruler or other simple everyday tools.

In earlier times, lathes were expected to be hand scraped, that made them "professional", like the big guys used. Of course, expecting a scraping job on a $300 lathe was ridiculous, even in those days, so they just put some random scraping marks on it after it was planed, milled, ground, or otherwise manufactured using machine tools. It was scraping, and it was done by hand, so the lathe was advertised as "Hand Scraped" in the promotional material. A lot of machines are "reconditioned" today by people with scrapers who make them look nice and pretty. They also put a nice coat of paint on the machine. It is still a worn out POS... Of course, some of the best machinery in the world is also finished by scraping, carefully and to very tight tolerances. A "reconditioned" $2000 Bridgeport series 1 is not one of the great ones... Caveat Emptor!

Edit: People who have the skills to do that work also have the skills to know the difference between fine work and a con job...
 

expressline99

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I do not think sheet metal shapes would do a very good job of mapping the wear on a lathe bed that is measured in thousandths. But, Russ is a pro, and I could be wrong. Ken's setup was an experiment designed for grinding a lathe bed with a normally handheld grinder mounted to a trolley, which was also used to map the existing wear and the progress.

Bed ways become swaybacked typically from use, with most work done near the chuck and therefore more wear in that area where the saddle typically moves back and forth a lot. The ways also wear sideways from side loading from tool to work loading. Before we start removing metal, we need a map of where things are at the start so we can make plans to remove the minimum amount of metal to get the desired results. We also need to test the progress of the work as it progresses, and finally we need to be able to know when we have accomplished the repairs to within the required tolerances. We make jigs and templates to assist with those measurements, which cannot be done with a ruler or other simple everyday tools.

In earlier times, lathes were expected to be hand scraped, that made them "professional", like the big guys used. Of course, expecting a scraping job on a $300 lathe was ridiculous, even in those days, so they just put some random scraping marks on it after it was planed, milled, ground, or otherwise manufactured using machine tools. It was scraping, and it was done by hand, so the lathe was advertised as "Hand Scraped" in the promotional material. A lot of machines are "reconditioned" today by people with scrapers who make them look nice and pretty. They also put a nice coat of paint on the machine. It is still a worn out POS... Of course, some of the best machinery in the world is also finished by scraping, carefully and to very tight tolerances. A "reconditioned" $2000 Bridgeport series 1 is not one of the great ones... Caveat Emptor!

Edit: People who have the skills to do that work also have the skills to know the difference between fine work and a con job...
OK a grinding trolley makes more sense to me now. Also, looking at it again I see it rides on the center flat of the vees.

They were $300 lathes you got a point there. So more likely it was some flaking at best? I did read that in a promo I found so you got me there. I can say my "rebuilt" Bridgeport should be awesome when I'm done. But I know exactly what you mean. Probably won't ever sell that once I get it done.

I could start bringing parts over for "us" to work on? :) (No pressure...please help me.) lol

Here are some pictures of the Logan bed to firm up what profiles I'm looking at here.

Paul
 

tertiaryjim

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The saddle on my Jet lathe was so poorly fit that the inboard side was 14 thousanths above the way unless a heavy load, like a deep cut, was placed on it.
I could bump it with a small dead blow and hear it smack the way.
The feed and threading rods actually lifted the OB so when machining it could pivot on the V-way and get some contact on the IB flat way.
Except the way wipers were so stiff and ill fitted that the saddle road on them...........
Then there's the problem that the saddle had no true reference points to measure from. Everything was convex and/or out of square to the ways and the dovetails which
were so bad I didn't even keep a record......
Very poor finish quality and loved to chatter.

The point is that everything has to be checked and understood before starting such a project. Everything!
I also found the tools I had weren't very good " actually they were crap" for getting into the V-way to scrape it.
Got it done and properly aligned after multiple tries. I think!
At least its solid and finishes are greatly improved plus other problems I listed are corrected.
It's amazing how the V-way can support an off-sided load and I had to role or re-align the saddles V to get the IB side to ride on the flat way and give me a square
or very, very slight concave face.
Had the lathe not been really crappy I wouldn't have attempted such a project with the limited " almost none" experience I had.
Wish I'd had the opportunity to start small and work up.

Now I know that I'm not ready to try a lathe bed.
 

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OK a grinding trolley makes more sense to me now. Also, looking at it again I see it rides on the center flat of the vees.

They were $300 lathes you got a point there. So more likely it was some flaking at best? I did read that in a promo I found so you got me there. I can say my "rebuilt" Bridgeport should be awesome when I'm done. But I know exactly what you mean. Probably won't ever sell that once I get it done.

I could start bringing parts over for "us" to work on? :) (No pressure...please help me.) lol

Here are some pictures of the Logan bed to firm up what profiles I'm looking at here.

Paul
Paul, your lathe bed does not show much wear visually in the photos, though the pics are not taken in the usual most suspect areas. You are not looking for wear at the sides of the bed, you are looking for it on the V's and the sliding flat ways themselves. The saddle contact on the V prisms does not normally extend to the bottom of the V. If there is heavy wear, you will normally see a step on the angled surfaces between where the saddle slides and where it does not slide. You can also feel it with a fingernail. It is usually worst about 12-18 inches from the headstock. Same for where the tailstock slides. It does not slide on the full width of the way, so you can see the wear versus the unworn areas. The tailstock wear will be farther to the right end on the ways than the carriage wear is, due to how they work together. The unworn areas are reference surfaces, as are all the unworn surfaces that were machined in the same setup when the bed was originally manufactured.
 

expressline99

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Paul, your lathe bed does not show much wear visually in the photos, though the pics are not taken in the usual most suspect areas. You are not looking for wear at the sides of the bed, you are looking for it on the V's and the sliding flat ways themselves. The saddle contact on the V prisms does not normally extend to the bottom of the V. If there is heavy wear, you will normally see a step on the angled surfaces between where the saddle slides and where it does not slide. You can also feel it with a fingernail. It is usually worst about 12-18 inches from the headstock. Same for where the tailstock slides. It does not slide on the full width of the way, so you can see the wear versus the unworn areas. The tailstock wear will be farther to the right end on the ways than the carriage wear is, due to how they work together. The unworn areas are reference surfaces, as are all the unworn surfaces that were machined in the same setup when the bed was originally manufactured.
Oh I wasn't trying to show wear. I will take those pictures later today. These pictures were to show where my reference points are and just general overview of where I would somehow have to measure from. I can tell there is considerable wear by messing with the carriage lock. If not loosened enough the carriage will quickly start to drag as you get away from the worn areas on the bed. Not really a very good test. But it's evident when using it.

One other issue I have is that the compound has enough slack in the vees to twist it by hand. This can be seen visually and heard to click as you do this. It has new gibs and I'm sure that could be tightened. But doing so limits the travel too much. Of course not tightened leaves it to have a lot of chatter.

But before anything can happen with the bed I need to figure out the replacement chip pan and get the legs done. Then properly level and wait and level again. I understand the extreme importance of leveling now. Can't be done until those parts are replaced.
 

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So more likely it was some flaking at best?
Flaking and scraping are quite different things. Flaking is deeper cutting done for oil retention pockets (and decoration.) It is also often mistaken for scraping, Flaking is also used to turn a sow's ear into a silk purse. The scraping done on the old Logan and SB lathes, when you see it unworn and pristine, is done by a scraper with very little nose radius, making flat cuts that cover a wider area than usual, and with areas between the marks that are not scraped at all. I suppose someone might say that is to "final fit" the lathe, or to add oil pockets, but I call it decoration. The lathes I am talking about here are typically smaller ones, built to a price point, often from the 1930's, 40's, and '50's. Earlier lathes were planed and then completely scraped in, later ones did not bother with 'scraping' at all, left them shiny.
 

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#19
I do not think sheet metal shapes would do a very good job of mapping the wear on a lathe bed that is measured in thousandths. But, Russ is a pro, and I could be wrong. Ken's setup was an experiment designed for grinding a lathe bed with a normally handheld grinder mounted to a trolley, which was also used to map the existing wear and the progress.
My sheet metal proposal was intended as the first step as a visual inspection tool to see how much wear may be on the ways. I agree, the bed looks good from the photos Paul posted so my template was also a prevention tool; Don't try to fix something that isn't broken. :big grin:

I think we agree that some things can be made worse by trying to get it as perfect or accurate as possible when there's no real point or value. e.g. On my 100 year old Lodge & Shipley I do a basic check on the ways for wear. I chuck up a piece of 1/2" drill rod with a drill check in the tailstock. I set up a dial indicator and run the carriage end to end. I get about .005" low spot where wear would be expected. I loosen the drill chuck, turn the rod 90° and do the same thing, with the same results +/-. My first thought was; I must be doing something wrong, there should be more wear for a machine this old. I think I'll leave it because I'm not sure I can get a cutting tool more accurate and a .005" drop on the centerline isn't a deal breaker on this machine.
 

expressline99

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The saddle on my Jet lathe was so poorly fit that the inboard side was 14 thousanths above the way unless a heavy load, like a deep cut, was placed on it.
I could bump it with a small dead blow and hear it smack the way.
The feed and threading rods actually lifted the OB so when machining it could pivot on the V-way and get some contact on the IB flat way.
Except the way wipers were so stiff and ill fitted that the saddle road on them...........
Then there's the problem that the saddle had no true reference points to measure from. Everything was convex and/or out of square to the ways and the dovetails which
were so bad I didn't even keep a record......
Very poor finish quality and loved to chatter.

The point is that everything has to be checked and understood before starting such a project. Everything!
I also found the tools I had weren't very good " actually they were crap" for getting into the V-way to scrape it.
Got it done and properly aligned after multiple tries. I think!
At least its solid and finishes are greatly improved plus other problems I listed are corrected.
It's amazing how the V-way can support an off-sided load and I had to role or re-align the saddles V to get the IB side to ride on the flat way and give me a square
or very, very slight concave face.
Had the lathe not been really crappy I wouldn't have attempted such a project with the limited " almost none" experience I had.
Wish I'd had the opportunity to start small and work up.

Now I know that I'm not ready to try a lathe bed.
Was the Jet lathe new? Or 2nd owner? Thanks for taking the time to explain your convex issues. First time I've read about someone with 1st hand experience with that.
Just wondering but were your scraping tools made at home or ebay brands?

So you only scraped the the saddle's Vees? So the bed is still convex or perhaps twisted?
Paul
 

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#21
Flaking and scraping are quite different things. Flaking is deeper cutting done for oil retention pockets (and decoration.) It is also often mistaken for scraping, Flaking is also used to turn a sow's ear into a silk purse. The scraping done on the old Logan and SB lathes, when you see it unworn and pristine, is done by a scraper with very little nose radius, making flat cuts that cover a wider area than usual, and with areas between the marks that are not scraped at all. I suppose someone might say that is to "final fit" the lathe, or to add oil pockets, but I call it decoration. The lathes I am talking about here are typically smaller ones, built to a price point, often from the 1930's, 40's, and '50's. Earlier lathes were planed and then completely scraped in, later ones did not bother with 'scraping' at all, left them shiny.
Bob I love the examples of poor quality restorations you give. "sow's ear" that's great.
 

expressline99

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#22
My sheet metal proposal was intended as the first step as a visual inspection tool to see how much wear may be on the ways. I agree, the bed looks good from the photos Paul posted so my template was also a prevention tool; Don't try to fix something that isn't broken. :big grin:

I think we agree that some things can be made worse by trying to get it as perfect or accurate as possible when there's no real point or value. e.g. On my 100 year old Lodge & Shipley I do a basic check on the ways for wear. I chuck up a piece of 1/2" drill rod with a drill check in the tailstock. I set up a dial indicator and run the carriage end to end. I get about .005" low spot where wear would be expected. I loosen the drill chuck, turn the rod 90° and do the same thing, with the same results +/-. My first thought was; I must be doing something wrong, there should be more wear for a machine this old. I think I'll leave it because I'm not sure I can get a cutting tool more accurate and a .005" drop on the centerline isn't a deal breaker on this machine.
Great idea for a simple test. I'll get some ground rod to try. I would be very surprised if mine was only out .005 and I for sure wouldn't go through this mess if it was. :)
 

Bob Korves

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#23
Paul, the ways the carriage rides on can have a lot of wear on them which will not not cause as much inaccuracy as you might imagine. Think about the tool against the work. The contact area is vertical where the tool it touching the center of the work. If the tool falls as it slides along the work, let's say it falls .020", the amount of metal cut changes much less than that, depending on the work diameter. On a larger diameter piece, the difference is negligible. Tailstock wear usually makes the center lower where it contacts the work, and that can cause a taper to be turned, but again, the depth of cut does not change as much as the tailstock center is low, it is much less. The tailstock can be shimmed to be a little high on the unworn portions of the ways, and a little low on the worn portions, and the work will show little variance along the cut. It can also be offset sideways to help the cause. The same sort of workarounds can be used with the carriage ways. Start with the tool a bit high on the unworn areas, letting it go a bit low on the unworn areas, and much of the diameter discrepancy goes away. LOTS of good work is done on worn out lathes. It is not ideal, but it gets the jobs done. A good machinist can do better work on a worn out lathe he is familiar with than a novice can do on a perfect machine. Food for thought. I recommend you do not be in a hurry to recondition the machine, and in more of a mode to LEARN the machine. Small steps...
 

tertiaryjim

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#24
expressline99
The machine was second hand and the first owner had no clue.
I found minor bed twist but spent some time to get it straight using Starrett 98 levels.
The lathe came from the factory as a reject mess.
A friend had given me a small surface plate that he got from his company for free as it had been dropped.
It wasn't very flat anymore but was good enough to use for scraping the compound which actually "rocked"
when placed on the plate.
The slide was scraped using a piece of cutoff tool and then used as a master to check the lower compound half and dovetails.
Speaking of dovetails, I had to machine and scrape a 60deg straight edge for those.
This is where I had to machine my first Gib key. That's an experience.
Keeping it reasonably true is difficult to impossible as the first cuts tend to make the thin material curve like a banana.
It's been a huge learning experience but after a whole lot of time and work, probably 10-20 times the work as I was learning from scratch
and made so many mistakes. Still do.
Later scraped the cross slide then the saddle as well as the bottom of the headstock and the rails it bolts to.

So a big question you have to ask is how much are you willing to spend on tooling and materials. It can be done fairly cheaply
financially if you find the right bargains and make your own tools but will be expensive in time and effort.
In my case everything I have is either cheap, broken, or worn out so someone has to do the work and I will use the tools on the next machine.
Even with all the time spent and frustration, most of which was self inflicted, it has often been very satisfying.
For practice I later got some angle plates during encos big sales w free shipping.
Scraping them flat and square also left me with useful tools and I can use the surfaces to practice flaking.
I'm still a amateur and there are many people on site who can give better advice but you can learn some from my mistakes.
 

expressline99

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#25
Paul, the ways the carriage rides on can have a lot of wear on them which will not not cause as much inaccuracy as you might imagine. Think about the tool against the work. The contact area is vertical where the tool it touching the center of the work. If the tool falls as it slides along the work, let's say it falls .020", the amount of metal cut changes much less than that, depending on the work diameter. On a larger diameter piece, the difference is negligible. Tailstock wear usually makes the center lower where it contacts the work, and that can cause a taper to be turned, but again, the depth of cut does not change as much as the tailstock center is low, it is much less. The tailstock can be shimmed to be a little high on the unworn portions of the ways, and a little low on the worn portions, and the work will show little variance along the cut. It can also be offset sideways to help the cause. The same sort of workarounds can be used with the carriage ways. Start with the tool a bit high on the unworn areas, letting it go a bit low on the unworn areas, and much of the diameter discrepancy goes away. LOTS of good work is done on worn out lathes. It is not ideal, but it gets the jobs done. A good machinist can do better work on a worn out lathe he is familiar with than a novice can do on a perfect machine. Food for thought. I recommend you do not be in a hurry to recondition the machine, and in more of a mode to LEARN the machine. Small steps...
It's all a lot to think about. Would it be horrible if I fixed the compound so that there isn't any slop...for the full travel? You guys gotta "enable" me a little bit. Can I buy a compound and scrape that in? I want a surface plate...(that's flat.) That way if I ruin the extra compound it won't matter. I would hope that could be classified as a small step? So we could spin this topic towards the compound and perhaps you guys can help me approach that. I have enthusiasm for miles. Even for learning the machine.

I should at least get this thing measured once leveled etc on the new legs.

Paul
 

expressline99

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#26
expressline99
The machine was second hand and the first owner had no clue.
I found minor bed twist but spent some time to get it straight using Starrett 98 levels.
The lathe came from the factory as a reject mess.
A friend had given me a small surface plate that he got from his company for free as it had been dropped.
It wasn't very flat anymore but was good enough to use for scraping the compound which actually "rocked"
when placed on the plate.
The slide was scraped using a piece of cutoff tool and then used as a master to check the lower compound half and dovetails.
Speaking of dovetails, I had to machine and scrape a 60deg straight edge for those.
This is where I had to machine my first Gib key. That's an experience.
Keeping it reasonably true is difficult to impossible as the first cuts tend to make the thin material curve like a banana.
It's been a huge learning experience but after a whole lot of time and work, probably 10-20 times the work as I was learning from scratch
and made so many mistakes. Still do.
Later scraped the cross slide then the saddle as well as the bottom of the headstock and the rails it bolts to.

So a big question you have to ask is how much are you willing to spend on tooling and materials. It can be done fairly cheaply
financially if you find the right bargains and make your own tools but will be expensive in time and effort.
In my case everything I have is either cheap, broken, or worn out so someone has to do the work and I will use the tools on the next machine.
Even with all the time spent and frustration, most of which was self inflicted, it has often been very satisfying.
For practice I later got some angle plates during encos big sales w free shipping.
Scraping them flat and square also left me with useful tools and I can use the surfaces to practice flaking.
I'm still a amateur and there are many people on site who can give better advice but you can learn some from my mistakes.
You've done a lot there I haven't made it to yet! I don't mind buying tools in fact I really enjoy it! For me I need distraction. My mind runs in 1000 directions at once.
So getting something specific enough to concentrate on is difficult at best. Lately time urgency is pressing on me. Keep getting the idea it might be over soon...Anyway let's hope not!

The plan is to make my own 30 degree straight edge if possible. Making a clamp type scraper like Bob showed me in his shop is on my list also. But I think I'm starting to get reeled in by the guys. Probably best!

Paul
 

tertiaryjim

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#27
I got a 2' X 3' plate prior to scraping the cross slide and also used it to better scrape the compound.
The compound had been greatly improved but the new plate showed some flaw that I corrected.
A clamp style holder is a good idea. Might make a couple of sizes and styles as you learn what you need.
Craigs list is a good place to look for surface plates.
You'll need pins to measure the dovetails and mics or an indicator setup to take the reading.
You could measure and make the gib first, also a new nut or screw if needed. How will you tap the nut?
I now wish I had made a log of the parts dimensions and slop before and after. Something to think about.
Keep your eye out for any cast iron stock or components you can use to practice on.
Take note of how the oil is delivered to ways and dovetails. You might be able to improve on that.
My hand flaking isn't up to snuff yet so I've not tried it on a machine component. The ways still move nicely.
There are others here who know what they're doing so read through the posts and keep a list of ideas and questions to run past them.
Lots of prep will save trouble later and keep a flow to the work. I was frustrated enough that I just jumped into it and dealt with problems as they came up.

The little lathe I have was so far out I could have thrown sand into it and improved the movement.
 

Bob Korves

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#28
It's all a lot to think about. Would it be horrible if I fixed the compound so that there isn't any slop...for the full travel? You guys gotta "enable" me a little bit. Can I buy a compound and scrape that in? I want a surface plate...(that's flat.) That way if I ruin the extra compound it won't matter. I would hope that could be classified as a small step? So we could spin this topic towards the compound and perhaps you guys can help me approach that. I have enthusiasm for miles. Even for learning the machine.

I should at least get this thing measured once leveled etc on the new legs.

Paul
Yes, the slop in the compound needs to be repaired, it is keeping you from using a fully operational machine. Have you taken it apart yet? Unless your compound is damaged beyond repair, I can see no reason to buy another one. You probably should show the disassembled pieces to someone who knows what to do. You might also want to bring the cross slide and it's gibs at the same time, they can be part of the issue and are needed to match the compound rest to. Read Connelly some more. The first two tasks in the sequence of operations for reconditioning a lathe are
1. Level the bed (see Sec. 26.35 through Sec. 26.39)
2. Scrape and align compound slide rest assembly.
So, get the legs and perhaps the chip pan on it, and level it... Journey of 1000 miles begins with a single step, Grasshopper... 8^)
 

Rustrp

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#29
You guys gotta "enable" me a little bit.
Enable? This only comes into play regarding tool acquisition. I would say buy but there are so many ways to acquire tools. :grin big:

As Bob said, legs and chip tray, then someone walking by will do a double take and remark, nice legs, good looking flared skirt on the tray, and level too. :big grin:
 

tertiaryjim

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#30
When leveling or removing twist, it takes time for the "system", bed legs n all, to fully react to adjustments.
The larger the adjustment, the longer it takes. Give the machine a couple days or more before re-checking.
The compound rides on the cross slide and could be scraped before leveling the machine " except " it is best if it sits on a parallel plane to the bed and cross slide.
That being said, you could indicate from reference points and unless the bed or cross slide look like corkscrews it would work fine.
Perhaps the experts will jump in on this. Please!
I didn't do this but everything was so far out there wasn't meat enough to machine it true.. Wish it had been otherwise.
Patience is a virtue.
 
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