Thread sizes etc. (a weird but not crazy topic)

[antoniosz]

I want to know the thread size of every thread in every (ok mine at least) fountain pen (cap/barrel, barrel/section, feed collar/section etc.).
Is there anyone who has already started such a project?  What kind of thread checker?  Share results? 
I know that repairs may not be the best forum for this (let me know), but i thought that I would have a better change getting answers here.

[FarmBoy]

Most are non-standard and the “exact” sizes are an educated guess. 
 

Get a thread pitch gauge to determine teeth per inch and use a calipers on the male threads and some trig to determine the size. Trace the threads with a razor point 0.3 pencil to determine how many leads there are. 
 

it works best if you can measure a few ODs and average them. 

[ParramattaPaul]

14 minutes ago, FarmBoy said:

Most are non-standard and the “exact” sizes are an educated guess. 
 

Get a thread pitch gauge to determine teeth per inch and use a calipers on the male threads and some trig to determine the size. Trace the threads with a razor point 0.3 pencil to determine how many leads there are. 
 

it works best if you can measure a few ODs and average them. 

FarmBoy summed it up nicely.

 

There are a number of factors here,  First of all, you have different thread types (metric versus ANSI, etc.) and pitches (TPI) used by large and small manufacturers (Mont Blanc, Pelikan, Waterman, Birmingham Pen Co., and Manuscript to name a few).  The too, hobbyists, bespoke producers, and 'cottage industry' pen makers using small lathes can randomly set the thread pitch each time they make a new pen.

 

FYI:  A basic guide to thread types (teesing.com)

[A Smug Dill]

1 hour ago, antoniosz said:

I want to know the thread size of every thread in every (ok mine at least) fountain pen (cap/barrel, barrel/section, feed collar/section etc.).

 

I agree with @FarmBoy. If you already have the pens in your possession, then both the ‘easiest’ and ‘best’ way to get accurate information on them is to do the measurements yourself, instead of scouring the web — let alone waiting for someone to offer you the information on a platter — for what all those measurements are supposed to be as far as the pens' respective manufacturers' (internal-use) design specifications are concerned. The ‘as-is’ factual measurements are more relevant than the ‘as-designed’ specifications, if you want to be able to make or buy parts to fit into your pens.

 

Minimising the amount of effort it takes to get the information you seek, and also avoiding the risk of your own errors in making those measurements, are secondary. You have as long as you need to do that work.

 

1 hour ago, antoniosz said:

Is there anyone who has already started such a project?  What kind of thread checker?  Share results?

 

You first.

 

Given the dizzying array of Chinese pen makes and models out there — and more are being introduced each month — I suspect it's folly to try to produce a consolidated archive of measurements for each. Yet, I think, for tinkerers that is the logical place to start; who really wants to mess with an Aurora or a Graf von Faber-Castell pen, or Sailor or Nakaya for that matter? If I want to put together a Frankenpen, then chances are some or all of the parts will be of Chinese make.

[austollie]

I'm happy to start the list with the Jinhao 599.  That has a standard M10 x 1mm (fine) thread pitch, as I found out when I screwed a standard bicycle hub axle bolt onto it.  See link below.

 

[antoniosz]

Thank you all.  (Farmboy - always good to see you in the same thread!).     I am aware of the different types. I was thinking 
something like this https://www.ebay.com/itm/133632986578 for fast checking or a microscope.
Thanks austollie for the info!
 

[austollie]

6 hours ago, antoniosz said:

I was thinking 
something like this https://www.ebay.com/itm/133632986578 for fast checking or a microscope

 

Just about every tap and die set comes with a set of thread gauges.  My cheap and cheerful set does.  However, as @FarmBoy pointed out, the vast majority of pens out there use some sort of proprietary thread pattern.  The Jinhao 599 took me by surprise, when I measured it.  The reason for my interest is that I wanted to make a custom barrel for a Lamy Safari, but that has a non-standard thread pattern (and I don't have a lathe to turn that on).  I noticed that the Jinhao 599 had a different thread pattern to the Lamy Safari and that's what caused me to check, just in case that it was standard (to my pleasant surprise, it was).

 

It is also worth noting that I use the term 'standard' loosely, even for the Jinhao 599.  My tap and die set has M10 x 1.5mm and M10 x 1.25mm taps and dies, but not M10 x 1mm.  M10 x1mm is used a fair bit for bicycles (e.g. rear derailleur hanger and hub axles), but I haven't seen it used elsewhere.  I have an M10 x 1mm tap/ die on order.  I'll have a crack at making a custom barrel for the Jinhao 599 with that and some aluminium tubing (which I will have to bore out to 9.1 to take the tap).

 

Please let me us know how you go with your project.

[Dione]

Pen Repair by Marshall & Oldfield lists quite a few

[tmenyc]

Also agree with Farmboy -- Antonio, the issue with the standard nut/bolt gauge like the one in ebay, which I have, is that they only work well on matching sizes, all standards that you'd find in a hardware store (they're the quickest way to find the correct nut or bolt size to match what you have, though, for a job around the house). Pen threads, to my viewing, are both too shallow and too varied for that to be useful. I measure distance and count, and the result is sometimes the average of a few attempts, and if it's a weird number I'll switch to metric for the same width (will start with metric for a euro pen). Thread gauges are also tricky to use with pens, again because the threads are often so shallow, but they are good confirmations of what I count. 

 

Tim

[eckiethump]

This company has quite a few less easy to find tap and die sets, sold singly as well https://www.tracytools.com/

As has been stated, the majority of sizes we need in pen work are bespoke, the likes of Laurence at https://www.penpractice.com/   will make taps and dies to suit, given the correct sizes.

I'm a satisfied customer of both, nothing more.

et

 

[Ron Z]

Victor.net has a variety of thread measuring gauges that will cover metric, SAE and British threads.  Reasonably priced.

[fountainbel]

Most American & German fountain pen makers used 36 TPI threads on vintage pens.

Single lead for section / barrel threads, 3 or 4 leads for the cap/barrel threads.

Francis

[eckiethump]

1 hour ago, fountainbel said:

Most American & German fountain pen makers used 36 TPI threads on vintage pens.

Single lead for section / barrel threads, 3 or 4 leads for the cap/barrel threads.

Francis

I have quite a few taps made different sizes at 36TPI, for use when making hard rubber caps, I am seldom  required to thread a barrel (external thread). Nearest stock size I have seen  is ⅜" dia. for taps. Check the fit, then gradually by hand graduate the size up until cap threads comfortably.

Eric

[fountainbel]

31 minutes ago, eckiethump said:

I have quite a few taps made different sizes at 36TPI, for use when making hard rubber caps, I am seldom  required to thread a barrel (external thread). Nearest stock size I have seen  is ⅜" dia. for taps. Check the fit, then gradually by hand graduate the size up until cap threads comfortably.

Eric

Unfortunately 36TPI threads on most vintage fountain pens are "off standard" so no taps and dies are available on the market. Consequently one has to cut them using a thread cutting knife on the lathe...

Francis

[ParramattaPaul]

8 hours ago, fountainbel said:

Unfortunately 36TPI threads on most vintage fountain pens are "off standard" so no taps and dies are available on the market. Consequently one has to cut them using a thread cutting knife on the lathe...

Francis

 

This is where I point out that vintage taps and dies and modern taps and dies are not necessarily interchangeable, and with that being the case, may not cut the same size or profile threads.

[fountainbel]

9 hours ago, ParramattaPaul said:

 

This is where I point out that vintage taps and dies and modern taps and dies are not necessarily interchangeable, and with that being the case, may not cut the same size or profile threads.

UNF 36TPI Threads are used by the majority of the vintage American and European pen makers. 

The UK pen makers probably used 36TPI -BSF threading.

However in both cases the threads pitch is completely identical, only difference is the thread. 

"top angle"  being 60° on the UNF threads and 55° on the  BSF threads.

This small difference in top angle is however not extremely important , when necessary one can fit an female UNF threaded part with a male BSF thread and vice versa.

36 TPI threads have a metrical pitch of 0.705mm. the closest standard metrical pitch  being  0.75mm, when necessary one can even combine a 36TPI pitch with a metrical 0.75 pitch as long as the engaging length is not longer as 5mm

The only important parameter is the external diameter/ inner diameter of  the part on/in which the threads have to be cut.

Hope this clarifies the matter

[GlenV]

This is a wealth of information! Thank you each for this contribution.

[antoniosz]

Awesome information - thank you all!