taps for an old pen cap restoration

[Patrick Verlende]

I have been a vintage fountain pen collector for over 25 years and my interest is mainly in restoring old pens back to writing condition again,if these pens are worthwhile and rare. I have very little experience in it, but I have a lathe and I know how to work with taps and dies. I hapen to have a big Le Tigre fountain pen 1918and the t ( made by Conway-Steward) with a number 8 nib, black ebonite. The lower end of the cap is severely damaged and I would like to restore it. I have bought an black ebonite rod from a japanese factory diameter 16.2 mm. I 'll bring it down to the required 15.3mm of the actual cap and I will remove the somewhat brassed clip from the old cap. The top end can be unscrewed from the cap and the thread is a single start 13mm. The thread to screw the cap on the pen is triple start 13 mm diameter. Conway Steward was a very britisch pen-manufactory and I suppose this is Whitworth Fine thread.
I need the taps to get the job done. Is there a possibility to get thes taps at a reasonable price through the IAP?

​

 

[hooked]

Good luck in finding your taps. You may want to figure out your thread pitch as well to make sure you get the correct tap. I understand Conway Stewart used some proprietary tap sizes that you might actually have to custom order, in which case, they would likely not be a "reasonable price".

Maybe contact Conway Stewart through their website and see if they can help you with tap sizes? Not the same company it once was, but perhaps they could help. You might also want to try to contact Vince at Turner's Workshop in the UK to see if he can help point you in the right direction. He is very knowledgeable when it comes to Conway Stewart pens.

We get penmaking triple-start m13 x 0.8 taps for the cap threads through a company called TAPCO. I am not sure if this is exactly what you are looking for, but Beaufort Ink in the UK sells these taps:

M13 x 0.8 - Triple lead plug (bottoming) tap

Triple lead - thread starts in three positions Plug (bottoming) tap M2 HSS steel Corresponding split die and intermediate tap (sold as a pair) also available

www.beaufortink.co.uk

I thought fine thread (British Standard Fine) taps, introduced around the time of your pen, come in imperial sizes and are the fine thread version of Whitworth (British Standard Whitworth)? I also recall reading at some point that Conway Stewart used BSCY (British Standard Cycle Thread) for their older pens. Also imperial, but this is why you may want to verify your thread pitch before purchasing a tap for that finial.

 

[mredburn]

Here is a link to the last group buy that had the prices from tapco posted,
Tap Link
A Single 3 lead tap in 13mm was $336.00 They dont stock them but make them to order. Beaufort Ink has them in stock for 104 euros.
Taps
If they have the correct profile they may be the best option unless you can borrow one.