inverted v templates

Wide enough to reach across the ways to level them. I would not buy one longer than that, the length will bet in the way on other jobs. Trusted (that means tested) parallels can be used to bridge longer work.

OK great I will see if I can get a 6"

Paul
 
A 12" . 0005 per foot level is plenty accurate and precise enough to level your plate. Without a good foundation isolation pad, your concrete floor will move the plate more than that.
 
A 12" . 0005 per foot level is plenty accurate and precise enough to level your plate. Without a good foundation isolation pad, your concrete floor will move the plate more than that.

I ordered the Shars 8" .0005 level. I am picking up 2" .120 square tubing to build my stand Monday. At least with the level and a 3 point support system I should be able to check it occasionally and fix any movement that happens. I've got to do the same with my lathe once I have the chip pan done....and the mill also. I hope to scrape both in but I will need some large squares also to get that done. After I make the straight edges. If I got done this year with one machine I'd be happy. :)

Paul
 
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...


We used to call this a Gasoline overhaul, clean, flake, paint
 
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
You can do a lot using the tailstock base, a precision level and an indicator.
 
A 12" . 0005 per foot level is plenty accurate and precise enough to level your plate. Without a good foundation isolation pad, your concrete floor will move the plate more than that.

Just out of total curiosity what is a foundation isolation pad? I don't have that I've got a 43+ year old concrete floor that isn't level. :)
 
We used to call this a Gasoline overhaul, clean, flake, paint

I can tell you the logan and the bridgeport didn't get any kind of overhaul. :) the BP was a total mess and still going. But until you guys told me about it I wouldn't have guessed people did this.
 
You can do a lot using the tailstock base, a precision level and an indicator.

Getting closer everyday. The replacement level is here(first one was broken in shipping) and I got an indicator base that is adjustable enough to get where I need it...I think.
 
It should be known that reading the Connelly book will warp your mind...at least it has mine. Now I've got this twisted thought process that is a datum point chain of surfaces interlinked into cumulative errors. Any of which could be multiplied by missing anything on your own test record...if you don't continuously update it and recheck constantly. The lathe not so bad on interlinked points if you follow standard operating procedures in getting it back to proper alignment...flatness and parallelism. Scrape straight down...not a problem if you do that everywhere based on all nearby points of reference. The mill TOTALLY different amount of points of reference and various datum collection areas and how it can end up way off down the chain if you are not careful! &)

Paul
 
It should be known that reading the Connelly book will warp your mind...at least it has mine. Now I've got this twisted thought process that is a datum point chain of surfaces interlinked into cumulative errors. Any of which could be multiplied by missing anything on your own test record...if you don't continuously update it and recheck constantly. The lathe not so bad on interlinked points if you follow standard operating procedures in getting it back to proper alignment...flatness and parallelism. Scrape straight down...not a problem if you do that everywhere based on all nearby points of reference. The mill TOTALLY different amount of points of reference and various datum collection areas and how it can end up way off down the chain if you are not careful! &)

Paul
Agreed, Paul. Taking shortcuts or using an ill advised sequence of operations when trying to get a mill geometrically correct will only make it more difficult to achieve and less likely to succeed in the end. Everything affects everything else. All corrective work must start from the machine datum point, in the case of your vertical mill the column face. Trying to fix a problem by working where it is first discovered will only make things worse overall and waste time and effort. Things work out better if you get each surface tested correct and finished in the proper order before moving on to the next one.
 
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