M10 VS M12 for Cap and Body

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RobS

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1)If buying a triple start tap and die set for the cap and body, is the following a correct statement:
A) M10 for a Bock #5
b) M12 for a Bock #6

2) Is the Mahestic Jr similar in size to a Bock #5 or #6. I'm not asking if it has a direct replacement, I'm just trying to get a scale of size? Looking into kitless, and I'm trying to gauge if I would like the #5 or the #6.

Thanks in advance
RobS
 
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duncsuss

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1)If buying a triple start tap and die set for the cap and body, is the following a correct statement:
A) M10 for a Bock #5
b) M12 for a Bock #6

IMO, no.

Disregard the size of the nib for now.

Start with the standard size ink cartridge/converter. The diameter is .25", so that's the size hole you have to drill in the back end of the section.

I have not been able to make the section-to-barrel threads smaller than 9mm without the threads breaking off.

If you try making the cap-to-barrel threads M10, that's a half-millimeter wall thickness, from which is subtracted the depth of the threads.

Ain't gonna work. At least, not for me.

I use M12 for the cap-to-barrel on the majority of my pens. I sometimes go larger, M13 or M14, if I'm making a chunkier pen.

When I started out, I made a couple of pens using #5 nibs, but mostly I use #6 now.
 

RobS

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Thank you for the reply Duncan, I like your work by the way.

Wow, that excites me and bums me out. I can not find any multi starts larger than M12 commercially available. However, it sounds like the M12 will work.

Maybe someone has something bigger that they are never going to use that might want to PM me.

Thank you
RobS
 

Mintman

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I agree with Duncan 100%. M12 is the smallest cap threads that I use(m9 section) I prefer the m13 it allows for decent cap thickness and I then use m10 for the section threads.
 

RobS

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Rob until a larger tap and die set you could order standard single thread tap and dies from Victor machine. It will let you play with the sizes inexpensively until you decide what ones you like the best. By then there may be another group buy.

Good call Curly:biggrin:
 

duncsuss

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I like your work by the way.
Thanks!

you could order standard single thread tap and dies from Victor machine. It will let you play with the sizes inexpensively until you decide what ones you like the best..
Agree completely -- this is exactly how I started, aside from it takes more turns to get the cap on/off there is no down-side AFAIK.

One thing I forgot to mention -- don't use a multistart thread for the section-to-barrel junction. (Or for the finial that holds the clip on the cap, or for a blind cap at the rear end of the barrel.)

Those junctions are expected to be "seamless", and no matter how careful I've been I can only get them perfect in one orientation, so when I assemble the parts there's always the chance I put it together wrong and there's a small ridge at the seam.
 

jalbert

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I use 12.5,14, and 15x.7mm x 3 start for the cap threads, depending on what size pen I am making. For the 12.5mm, I usually use a #5 nib, although I recently found out I really like how a #6 looks on that size pen. I use a #6 on the 14 and 15mm pens, and sometimes a #8 on the 15mm when I am (or a customer is) feeling like spending the $$$ for the nib.
 

Phil Dart

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Hi Rob
Thanks for your PM - I'll get the drawing off to you. I've also sent you a PM containing what I'm about to say, as this post will quite possible be deleted as it will mention my own products and will possibly be deemed to contravene the advertising rules.

The Jr Majestic is a size 5. The majestic (not junior) is a size 6. Contrary to replies here, yes, do consider the nib size from the outset, but as already stated, all measurements stem from the need to get a converter in and out of the pen. The cheap converters are a bit narrower, but the better ones - the ones with the metal seals, including the Beaufort Ink converter are about 7.8mm, so you need an 8mm hole at the back of your nib connector. That is your starting point.

The most common cap thread size is 12mm, but people also design down to as little as 9mm, which is why I say consider your nib size from the outset. As you have already seen, we have 10 and 12mm triple lead taps and dies at the moment, but we will have 11 & 14mm within the next month or so, followed by 9 and 13mmm after that. (cashflow prevails I'm afraid)

I hope that helps
 

RobS

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Thank you Phil, that helps out quite a bit. Looking forward to the print as well.

Cheers
RobS
 

mredburn

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If I use 10mm for cap threads I use 8.5 x .75 for the section threads and only on metal.
You can use the Monteverde convertor with no issues for fountain pens. THe Schmidt coverter is a trifle large but I have made them work. The Monteverde brand is slightly thinner in diameter.
For that small a thread you can only use #5 nibs. Rollerball pens are not a problem.
 

ffloyd

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I was just surfing the IAP site. It is good to know that the triple start tap and die sets are available again. I'm just getting into kitless, but the fountain pens I've seen from other people are much better with a triple start thread. I am still torn 12mm or 14mm? My most comfortable pens are along the JrGent size range.

Which one 12mm or 14MM?
 

magpens

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I was just surfing the IAP site. It is good to know that the triple start tap and die sets are available again. I'm just getting into kitless, but the fountain pens I've seen from other people are much better with a triple start thread. I am still torn 12mm or 14mm? My most comfortable pens are along the JrGent size range.

Which one 12mm or 14MM?

What size are available and where can I get them ... please ?

Silverpenparts seems to be out of stock.
 

RobS

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Depends on the nib size. Based on my math a 14 will work for a #6 Jowo.
10 & 12 can be found here.
 

mredburn

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Beaufort Ink Beaufort Ink - High quality refills, nibs, pen kits and blanks for discerning pen makers.

I use a #6 feed in my jr sized series kits all the time with a 12mm thread. I use 12mm for the cap, 10 x .75 for the front section or rollerball nose cone. The out diameter of the pen body on a JR series pen is around 13mm .510 ish and The cap 14.5mm .565 ish. WIth the hole for a 12mm drilled or bored 11.25-11.3 you have plenty of room for a #6 nib.
 
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RobS

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thanks for listing the link, i screwed up and left it off, that was the link I was looking for.
 

Phil Dart

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Thanks for the link Mike. Just to let people know, we will also have 11x0.8 and 14x0.8 in stock in a few days time. They've been shipped from the manufacturer - just waiting for them to arrive.
 
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