Hi there guys,

I have no idea if anyone can help me but its worth a try.

I have a reasonable understanding of lathes and milling machines but no practical knowledge of manufacturing.

I am designing something for prototype and could do with a little guidance from experienced machinists.

The basic outline is as follows: I have 2 tubes which need to be threaded on to each other to create a seamless join, OD 1.000 inch ID 0.700. I plan to have a total overlap of 1 inch with roughly 0.300 threaded section positioned in the middle of the 1 inch overlap. I also want to have 2 grooves for orings, one on each side of the threads, to seal the join.

The finished product will be machined out of aircraft aluminium so i would like a minimum wall thickness of 0.025

In my current drawings i have a space for the threads to be cut within the 0.860 to 0.940 diameter range on the male part and between 0.950 to 0.870 diameter range on the female part.

I have 2 main questions please;

Firstly is this diameter range suitable for an M24 x 2 thread to be cut? if so what would the turned/bored diameters need to be to prepare for cutting? If not, is there a more suitable thread you can suggest?

Secondly I have factored a 0.010 diameter clearance between male/female parts which fit inside each other, Is this too tight, just right , or too loose? The parts will be supported against each other with o rings.