Swing over bed (?)

[fiki]

hey all!

Can anyone please explain what actually swing over bed on lathes is?
Whats its corelation with max. turning diameter?
Some kind of diagram or picture with those dimensions could help alot...

Tnx!

[skmetal7]

its twice the distance from the center of the chuck to the bed, or the max diameter a lathe can turn.

[fiki]

so according to you its the same thing? max turning diameter and swing over bed?
the thing is that different manufacureres seem to have a different definition for what swing over bed is. Because I saw a different values for max diameter and swing over bed on same machine. To be more confusing, sometimes max diameter is half the swing and sometimes is twice a swing...All i want is that all manufacturers decide what swing is gonna be

[Geof]

Originally Posted by fiki ...All i want is that all manufacturers decide what swing is gonna be

Not going to happen . The ones who make small lathes will probably use diameter because it sounds bigger.

[svenakela]

Originally Posted by fiki so according to you its the same thing? max turning diameter and swing over bed?

In the end it's the same thing, but the measurements are not.
Swing Over Bed is the radius. Max diameter is twice the radius.
On some machines the Swing Over Bed can be bigger than the radius as the tool holder can interrupt with the goods.


Regards,
Sven

[fiki]

Originally Posted by svenakela In the end it's the same thing, but the measurements are not. Swing Over Bed is the radius. Max diameter is twice the radius. On some machines the Swing Over Bed can be bigger than the radius as the tool holder can interrupt with the goods.

for example...certain machine has max diameter 360 and swing over bed 600 mm...i know what max diameter should mean: that u can work on piece with max dia of 360 mm...right? and what does then 600 mm mean? that center of a tool holder can travel 600 mm from center of a chuck? or what? the thing is that i sell CNC machines and every manufacturer interprets that values diffrently..thats the problem so i only work with max diameter value because it means the same everywhere

[Al_The_Man]

I always understood that the term swing in N.A. refers to the maximum turnable diameter, I believe in the UK they used to use the radius value for swing, which confused matters a bit.
There is also the swing across the cross slide and through the gap, if a gap bed lathe.
Al.

[svenakela]

Originally Posted by fiki for example...certain machine has max diameter 360 and swing over bed 600 mm...i know what max diameter should mean: that u can work on piece with max dia of 360 mm...right? and what does then 600 mm mean? that center of a tool holder can travel 600 mm from center of a chuck? or what? the thing is that i sell CNC machines and every manufacturer interprets that values diffrently..thats the problem so i only work with max diameter value because it means the same everywhere

Swing over bed is the maximum size that can be mounted without hitting the bed. the max diameter in your example probably refers to the swing over the slide, the tool holder cross slide. The distance between centers or tool travel is something else, otherwise your provider messed the definitions up.

[fiki]

tnx sven...just wanted to see how many explanations can i get...since i deal with used machinery its a pain in a but, every dealer interpets differently and you get chaos in dimensions
but its little bit clearer now for me...

[DareBee]

Don't forget that sometimes max diameter can be given as dia in the GAP.
My large lathe is 36" X 168 but I can swing 44" in the gap (about 16" long) and only 30" over the carriage.