Metric threading question.

[Arnak]

Hi Folks,

I was going to attempt to thread a piece of rod using and carbide threading tip which is 1.75mm for a 12mm thread when I noticed that my Warco lathe for some strange reason does not have a 1.75 gearbox setting.

It has a 1.8 instead.

Would this be acceptable or would the cumulative difference over the length of a long thread make a difficult fit for the nut?

Thanks,

Arnak

 

[Darren English]

It's not that much out, give it a go and see what happens!

And if you are just threading the rod to fit a nut on, it is only effective along the length of the nut and not the rod.

Good luck

 

[Antman]

2 suggestions: M12 X 1.5 is a commonly available thread, you might try a place stocking truck spares for that size nuts and bolts and use that instead. Also 1.75mm = 7mm/4 so you should be able to find gears to cut that thread if yours is the sort of lathe with a box full of loose changewheels.
Ant

 

[chipenter]

You could posibly change the feed to the gearbox to give you 1.75 if you have the gears, or use 12mm fine thread at 1.25 is an other way to go .
Jeff

 

[Arnak]

Hi Guys,

Thanks very much for the advice.

Good point about the nut length I hadn't thought of that.

Happily it can cut the other sizes, 1.25, 1.5 etc it is just the 1.75 that is missing.

I will give it a try and see how the nut fits.

Arnak