# Cap/barrel threads on section?



## Robert111 (May 16, 2012)

Anyone doing this? Then use left-hand section threads into the barrel. 

This would be useful when the barrel material is fragile and you're using an ebonite section, for instance.


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## Robert111 (May 16, 2012)

Holy Moly! JUst looked at Soligen's post "Ancient Amber" and there it is!

http://www.penturners.org/forum/f13/ancient-amber-hidden-threads-kitless-97400/

Somewhat different reason for putting cap threads on the section, but Soligen's design would also overcome the problem of delicate barrel material.


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## watch_art (May 18, 2012)

I've talked to a couple of custom pen makers about threads on the section for the cap.
This could create a week spot with all the threads in one spot.  Section, barrel, and cap threads all overlapping in one area.
It's not something I'll do.


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## Timebandit (May 18, 2012)

Robert111 said:


> Anyone doing this? Then use left-hand section threads into the barrel.
> 
> This would be useful when the barrel material is fragile and you're using an ebonite section, for instance.



This wouldnt help in that instance. This would be weaker, if the barrel was weak. If the triple start threads are on the section, you have to make a smaller  temon on the fragile material (barrel), to be able to  screw into the section. With the threads triple start threads on the barrel (like normal), this would leave more material on the barrel threaded section, therefore making it stronger for the section to screw into. 
And for the left hand threads, i wouldnt recommend it. Only because most people who buy pens, have other pens. Could be 5, could be 100 or so. And il bet most of them if not all of them, have right hand threads. This means they have to remember to turn the section on this pen the other direction, and if they forget and go to turn it the normal way, and it wont come off, so they crank it harder until they strip the threads or snap that tenon off and than you have a big problem. I would avoid left hand threads is these soft materials. If it were metal thats one thing, but with these soft materials, they will strip threads or break tenons.



watch_art said:


> I've talked to a couple of custom pen makers about threads on the section for the cap.
> This could create a week spot with all the threads in one spot.  Section, barrel, and cap threads all overlapping in one area.
> It's not something I'll do.



I dont think the weak spot would be on the section in this case, it would be on the tenon on the barrel that screws into the section. To much pressure screwing it in and that tenon could snap off. It can happen with the threads the other way as well(like normal) but i think it would be less likely. Also, with the triple threads on the section, any pressure against the cap or barrel up or down while the pen is capped will also exert that same force the the barrel threads that thread into the section, since these are the two points of contact between the cap and the barrel(the section and the cap). This is the weak spot. With the triple threads on the barrel this force i only exerted on the cap and the barrel since these are the two points of contact between the cap and barrel.


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## AurelianC (May 18, 2012)

I know mine is in aluminium, but why not do it like in my photo. I will try it in ebonite and see how is working.


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## Dustygoose (May 19, 2012)

I like the design of that aluminum pen.  Looks simple and can make for a smaller diamiter pen.


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## chugbug (May 27, 2012)

*cap/barrel threads on grip-section...*

Hi Robert,

I've made a few different style pens with the threads on the grip-section. One was a bulb filler from soligen's tutorial he posted a while back. The other incorporates the same grip-section, but in a different style pen. The third pen places the threads on the very front of the grip-section.

Left hand threads... But to address the other part of your question, I don't use left-handed threads though. Instead, I use a rubber o-ring. The o-ring keeps the smaller threads tight so they don't loosen. The o-ring adds an additional feature in that it creates a seals allowing the barrel to be filled directly with ink. 

Weak joint... I've not had any issues with weakness in any of the parts when doubling up on the threads. But in my case, I use a larger set of (custom sized) threads for the outside. And on the Nanga, I taper the barrel enough that the cap can't be overtightened.

Here are a few links to the pens I mentioned:

1. This link is to the bulb filler's I made using soligen's tutorial (with the threads on the grip-section): JEB's Pens - Custom Fountain / Bulb Fillers

2. This is s small pocket fountain pen I make (call the "PFP") that incorporates the same double threaded grip-section: JEB's Pens - Custom Fountain Pens / PFP.

3. This pen is different from the other two. On this one, I placed the threads on the very front of the grip-section (up at the nib): http://www.jebspens.com/fp_custom/nanga.htm.

Hope this helps...John

John E. Brady (JEB)
JEB's PENs
www.jebspens.com
Handturned Pens/Pencils
& Custom Fountain Pens


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## Robert111 (May 27, 2012)

chugbug said:


> Hi Robert,
> 
> I've made a few different style pens with the threads on the grip-section. One was a bulb filler from soligen's tutorial he posted a while back. The other incorporates the same grip-section, but in a different style pen. The third pen places the threads on the very front of the grip-section.
> 
> ...



Thanks for the information, John. I can see the threads on the Nanga, but just barely--looks intriguing! The PFP is a cute pen. I imagine it's very popular. Your discussion of the way you came to design it is interesting. And I like the idea of an eye dropper--I have a Noodler's freebee that's an eye dropper and it'll hold a lot of ink. Where do you put the o-ring, if you don't mind saying?

There's  a lot here to think about, John. I found your site over a month ago and have returned a few times to read more. And there's plenty to read! Thanks again for sharing your designs and thoughts.


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## soligen (May 28, 2012)

Robert111 said:


> Holy Moly! JUst looked at Soligen's post "Ancient Amber" and there it is!
> 
> http://www.penturners.org/forum/f13/ancient-amber-hidden-threads-kitless-97400/
> 
> Somewhat different reason for putting cap threads on the section, but Soligen's design would also overcome the problem of delicate barrel material.



I do most of my pens with the threads on the section.  I guess i'm a bit of a maverick that way 

The way I had to do it on that pen is more difficult than the way I usually do it.  

Please see my Bulb Filler tutorial in the library for a step by step on the way I usually do it.


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