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I have not forgot I just have not had time to sort it out my life is manic at the moment the pen stuff is on the back burner. Range bookings and range licences are the priority at the moment.

Wow that was intense. I had a couple of hours free this afternoon so I have popped a transmission in the post. David if you can ID the tread I will be very very grateful. You don't have to return the male and female bits I have got loads of them. The nearest I have got to it is M7.5 x 0.5. The transmissions come from either China or Taiwan.

I will keep an eye out for them. Do you want some Walnut offcuts for your pen making, they are superb bits of wood, cut with the grain from planks so around 3/4" to 1" square. Assuming the Viking has not lit the workshop stove with them...

Yes please l will cover postage and packaging.

What size blanks do you prefer? Length and section, metric or imperial is good :)

We have Black Alder, Beech, Oak, Ash, Maple as well as the Walnut and we are on the saw in the morning with this lot (Alder & Beech) as well. For scale they are 1500mm/60" long.

The ones I buy are roughly 130mm x 25mm.

I have given up trying to identify the thread size. I have ordered in a bunch of 8mm OD by 6mm ID brass tube and some 12 mm solid brass bar I am going to make my own transmission tubes and couplers and cut them with a thread of my choosing for my custom builds.

Your parts have come back from the shadowgraph people who tell me it is an unknown, best they could offer is 9/32" by around 52 threads per inch however even that pitch varies depending on where it is measured.

The 52 did make me think it was a metric ultrafine 7,3x0,5mm pitch however such a thread does not appear to exist in he real world.

Sorry I cannot help any.

Thanks for trying. I gave up on it.

Up date.
The thread is in fact M7.5 x 0.5.
Originally I tapped a length of 8mm brass tube internally. 8mm is a common size in the pen making game but the the tube wall is very thin. So whats happened is when I have ran the tap in it has bulged the tube just enough to be a loose fit on the male thread it screws onto.
So what I did was cut some brass 8mm outside diameter rod to 4 inches in length. Popped a piece in a four jaw chuck. Clocked it then drilled a pilot hole. I then started going up in drill size until I got to 6.5mm. I then switched to reamers starting with 6.6mm and I went up in increments to 6.79mm. I then switched to a M7.5 X 0.5 tap.
And it worked I now have a transmission tube that is 4 inches long as opposed to a half inch one. So I can make them any length I want now.


So I can make a 7.62x54R pen using a fired case.

hm whats next.