7x Spindle mod and max chuck

[Richard23]

Is there a way to modify the spindle on a 7x lathe to over 1 inch? Or a replacement spindle with a through hole about that size?

And what is the biggest usable chuck one can put on the 7x? I see there are 4", 5", and 6" options. I imagine the 6" might be a little big; the jaws may hit the bed?
Rich

[545Kurt]

I bored my spindle out with a boring bar to 7/8". I think 1 inch would be pushing it. If you have a look at the output gear on the spindle for the gear change you will find it is not much larger if at all than 1 ". I also put a 5 inch chuck on which I love. Gives the lathe a smoother operation I feel due to the additional rotational mass.
Kurt

[Twmaster]

One inch would be bad. The OD of the spindle is only 30MM (1.18")

Frank Hoose of www.mini-lathe.com reports the 5" chucks fit.

[Gary Gill]

I use a 5" chuck and adapter plate from LMS. It works well for me.

[Twmaster]

Thanks for the report Gary. My 4" is just an ultra fine hair too small to grip a small crankshaft from a weed whacker motor. I may end up having to get a 5" chuck....

Yay! More money!

[blades]

Originally Posted by Twmaster Thanks for the report Gary. My 4" is just an ultra fine hair too small to grip a small crankshaft from a weed whacker motor. I may end up having to get a 5" chuck.... Yay! More money!

Ok, I gotta ask.... what are you doing chucking up a crank from a weedwacker motor?
Definately sounds like something I should know about!

[Twmaster]

Making airplane engines.

[blades]

Nice! I was interested for awhile in doing a weedwacker powered boat. Had the engine, but not enough motivation or $$ at the time.