machine tapers

[clueless77]

Is int 40 the same as cat 40. Tried to find out by google but all the sites I found just say something vague about 40 tapers and some dimensions for some tapers but no tables to compare the two. I know it's probably a really obvious thing to you machinists out there but I'm a bit numb on the subject. Advice greatly appreciated.

 

[Maker]

As far as I know, they are the same, they definitely have the same taper but I think the drawbar thread might be different or something like that.

 

[CRB]

This has cropped up before, but I am off to bed.

 

[clueless77]

Found a good vid on youtube called taper talk, explains better than tables. Thanks for the helpful reply though Maker.

 

[Maker]

Wikipedia isn't very clear on the matter, they're both NMTB tapers with a taper of 3.5 inches per foot. ISO has a metric draw thread but it doesn't say the difference in CAT, just that it is more modern and suggests it has different draw thread and flange.