inverted v templates

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.
 
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. :)
 
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...
 
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.
 
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
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
 
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.
 
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^)
 
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:
 
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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