No32 Souvlaki & On the Subject of Necessity Being the Mother of Invention.....

[Roger Payne]

I don’t know of any off the shelf supplier, though others might. I have one, though it was purpose made by my late machinist Graham Smith.

(He made me a supply of lead screws & grat assemblies for Mk1 & 2 scopes & afterwards gave me the tap he'd made for the job).

[Peter Laidler]

I have to say that in the couple of years that I have repaired the sights I have only ever had to make a couple of lead screws and that's because they were missing! Worn lead screws are not a problem in Mk3's and L1A1's and are an easy fix in the Mk1's and 2's

Springs come by the foot and..........

[bigduke6]

Rog, re your threading technique, thats one way but to get it true use the same set up but use a die nut holder, put this up against the part to be threaded and use the tail stock fixed and wind in till its hard against the die nut holder......... as before wind/turn main chuck down, the die nut holder will or should stop itself against the lathe then its a matter of winding the tail stock in to keep the die holder square against the job, once mastered its easy, you can use this also to get a start on any threading etc to make sure its true and carry on as normal once the thread has started......

[Brian Dick]

I have a baking oven made by Lauer. It's tall enough to suspend a barreled body using a hook. I prefer to install the barrel and paint it as a unit which makes for a very nice, even job. I admit that Suncorite is so tough that sometimes the body wrench won't even mar it if you're just changing out a barrel.

[bigduke6]

Taps and dies for the screws are around £280 for two sets IIRC, as they have to be made, I made enquiries some time back to complete some bits for Roger....... Oh and a two start tap you really need a jig to get it started or follow advice in previous thread use lathe etc but use a centre in the tail stock and wind in till it touches the centre of the tap.

If you have the eyes of a S**t house rat and patience of a saint and have a imperial cutting box on a lathe then its possible to make your own taps and dies,

[Peter Laidler]

The real Q is to ask what you need the taps and dies for? To replace missing - fair enough. To eliminate backlash - no need at all

Or, and no offence to anyone who is feels confident enough to tackle a rebuild on the hoof, without any formal instrument, mechanical or optical training, are we just imparting this info to aid the enthusiastic amateurs to xxxx their telescopes up.

Ask me about the now totally destroyed Mk3 drum that was 'repaired' because it was stiff. Well, it is now! Sorry but that's how it is in real life..................

[Roger Payne]

Thanks Geoff. Tip much appreciated.

[bigduke6]

The real Q is to ask what you need the taps and dies for? To replace missing - fair enough

Just a few lathe tips and an answer to someones question Peter.......
Rog, watch this space as I'm just threading some 6mm and 8mm bar to make some crank case studs for my Matchless with 1/4" and 5/16" UNF thread...........if any anoraks are reading this the thread should be BSF or the old cycle thread, but you can still buy stainless steel nuts in UNF at a reasonable price, BSF/ Cycle thread nuts in stainless cost a small fortune.

[bigduke6]

Few pics for Rog,

As described in previous posts, this method will guarantee the nut runs square and not wobble all over the place, with practice a thread can be done in minutes, basically its a manual capstan lathe !!
You need to wind in the tail stock shaft whilst turning the chuck, always use some cutting paste etc.




I've used the tool post holder to support the die stock and its free to move along





A set of the above studs sell for around £25 on ebay and there not even stainless...... although the tap and die set cost me £30 I took the plunge as I don't have many UNF or UNF taps and dies, my normal source is the car boot sales............. I've more Whitworth taps and dies you can you can shake a stick at.

[Roger Payne]

Thanks for that Geoff. I've already made a few of the screws according to Peter's method, but I have enough brass to make about another half a dozen so I'm going to whilst I'm on a roll. I'll follow your suggestion for cutting the thread; what you advise is virtually what I was doing, except your method holds the die at right angles to the job better. Cheers.