New Lathe Twisted bed

There are different types of level. Level relative to level is one and then Level to the floor, is another one. as I think I have seen on here somewhere before, It does not have to be level in the traditional sense, But has to be level in a relative since, Think of it this way, If the floor slopes at a 2 degree angle, front to back and a 3 degree angle left to right, Then if you wanted it flat on the floor, your ways would actually be on a 2 degree from headstock to tail stock. and 3 degrees front to back. you would adjust your level to show level when set on this, then verify your head stock is level to that, then move down toward the tail stock and verify it is the same. It can be a pain to level this way on a sloped pad/floor, but some people do that rather than having to build up or jack up one end that much. or at least that is what I see and have seen. No formal training on any of this. just reading such. this site has helped a lot.
 
Yes, true; in fact, Warner & Swasey, manufacturer of turret lathes made just such an adjustable level with the vial fastened at one end and adjustable by knurled screw at the other end.
 
Folks have been mangling the English language (or any language for that matter) since language was invented. ;)

It might be more accurate to use the word 'truing' when describing lathe adjustments. The bed doesn't have to be level per se, but the headstock end of the bed needs to be on the same plane as the tailstock, front to back, to remove twist. Left to right is a don't care.

You could mount your lathe to the side of your house if you wanted to, as long as the bed is twist free. But if you do, I want pics! :D
 
wrmiller said:
Folks have been mangling the English language (or any language for that matter) since language was invented. ;)

It might be more accurate to use the word 'truing' when describing lathe adjustments. The bed doesn't have to be level per se, but the headstock end of the bed needs to be on the same plane as the tailstock, front to back, to remove twist. Left to right is a don't care.

You could mount your lathe to the side of your house if you wanted to, as long as the bed is twist free. But if you do, I want pics! :D
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The exception to the statement that level does not matter so long as both ends of the lathe are in the same plane is with lathes that have three or more sets of legs, common on longer machines; in order to "level" them as a practical matter one must have them level in both directions to ensure that the ways are not high or low in their length, in the case of a very long machine, like an ocean wave, although, machines in this class can be "leveled" by a laser, I saw a large lathe, 16 ft. swing and over 100 ft. between centers that was leveled by conventional means and failed to deliver work of sufficient precision; after laser leveling it preformed satisfactorily.
 
As a simple hobby machinist, I have no experience with lathes that large. Exception duly noted. :)
 
benmychree said:
The exception to the statement that level does not matter so long as both ends of the lathe are in the same plane is with lathes that have three or more sets of legs, common on longer machines; in order to "level" them as a practical matter one must have them level in both directions to ensure that the ways are not high or low in their length, in the case of a very long machine, like an ocean wave, although, machines in this class can be "leveled" by a laser, I saw a large lathe, 16 ft. swing and over 100 ft. between centers that was leveled by conventional means and failed to deliver work of sufficient precision; after laser leveling it preformed satisfactorily.
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I have a transit my dad used to use for leveling long lathe beds. He used to level deep hole trepanning machines, which some of them had bed lengths of over 120 foot in length. Most were in the 40 to 60 feet in length. A transit can get a bed level level within a couple of thousandths in ten feet under the right conditions. As mentioned, lasers are more common to use. You still have a margin of error with either method used as well as how stable of an foundation you have for the machine.
 
4gsr said:
I have a transit my dad used to use for leveling long lathe beds. He used to level deep hole trepanning machines, which some of them had bed lengths of over 120 foot in length. Most were in the 40 to 60 feet in length. A transit can get a bed level level within a couple of thousandths in ten feet under the right conditions. As mentioned, lasers are more common to use. You still have a margin of error with either method used as well as how stable of an foundation you have for the machine.
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The lathe that I mentioned was set for deep trepanning; had a bunch of big steady rests and high pressure coolant system and had two carriages that the operator rode on with control panels; all its functions had been converted to CNC so the operator could control everything from either carriage; it had a power tailstock mover and powered tailstock quill; It was used on one job, that of machining giant "pins" that were seismic features of the new Bay Bridge in San Francisco Bay.
 
I've seen pictures of a couple of the one's you are talking about. They are monsters and hugh! I one's we dealt with back then were set up to drill a maximum of- 4-3/4 hole size. Most were set up to drill about 3" ID x 32 foot deep from both directions at the same time. Any chance of sharing any pictures of them?
 
4gsr said:
I've seen pictures of a couple of the one's you are talking about. They are monsters and hugh! I one's we dealt with back then were set up to drill a maximum of- 4-3/4 hole size. Most were set up to drill about 3" ID x 32 foot deep from both directions at the same time. Any chance of sharing any pictures of them?
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I do not think that I have any pictures of the lathe; I was at the location in Napa, Ca. buying some machinery at the old Kaiser Steel plant where the contractor was leasing space to do the Bay Bridge job, which was hollow tube with about 4" wall thickness rolled up and sub arc welded, with sections of about 2" wall thickness in places, I was told that the thin sections were for seismic deformation; the completed length was about 60 ft, with stainless steel overlay in sections that was machined to a fine finish. the site has been literally leveled and all the machinery either scrapped or sold. The site looks forward to residential and commercial development.
The big lathe was, I think used for production of marine tail shafting; I have seen a picture of a shop with a bunch of these lathes of various sizes, a shop doing one thing; trepanning. Also I remember that in the middle of the bed there was a channel with two big square threaded screws that counter rotated to convey the chips out to the tail end of the machine to be loaded into scrap skips. On these lathes, the bed must be more than twice the length of the work being trepanned. The bed was made in sections and bolted together so as to be able to be produced in virtually any length and to be transported. The ways were flat, and at least 12" wide; It may have been a Niles lathe, but I do not remember for sure; I think I was told that it dated from the early 1950s; odd I think, as there should have been a surplus of them from WW-2 production.
 
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