Nib Flex, line variation and grams of force

[Richardtractorguy]

66632

This is one of my Geha pens. The nib is semiflex. As you can see it takes 176 grams of force to separate the tines 1 mm. Depending on the ink the 1mm separation of the tines translates to a much thicker ink line. How much separation force does it take to achieve maximum flex on a superflex nib and how wide is the tine separation?

[Pterodactylus]

66632

This is one of my Geha pens. The nib is semiflex. As you can see it takes 176 grams of force to separate the tines 1 mm. Depending on the ink the 1mm separation of the tines translates to a much thicker ink line. How much separation force does it take to achieve maximum flex on a superflex nib and how wide is the tine separation?

Oh my gosh!

Why are you torturing this nib?
This hurts only looking at it!

And who cares with how many grams a nib spread until you sprung it?

Writing with a flexible or semi- flexible nib is a a matter of feeling it, not measure something.

[catbert]

OP may be interested in David Nishimura's experiments along similar lines. https://vintagepensblog.blogspot.com/2015/07/measuring-nib-flexibility.html

[Richardtractorguy]

Actually it's important to me. I don't know how much pressure other people are applying to achieve line variation. Knowing how many grams of force can be applied and still not reach the yield point of the metal will prevent damage. In the picture above I am not applying very much force even though the scale makes it look like alot. Don't worry Pterodactylus I very much cherish my Geha pens...I don't see any evidence of plastic deformation on the tines. When I write with this pen I rarely spread the tines half of what you see here.
Thanks Catbert!! Excellent article!! That is exactly what I was looking for!!

[FredRydr]

...How much separation force does it take to achieve maximum flex on a superflex nib and how wide is the tine separation?
How long is a piece of string? You'll need fewer variables.

[Jon Szanto]

OP may be interested in David Nishimura's experiments along similar lines. https://vintagepensblog.blogspot.com/2015/07/measuring-nib-flexibility.html

Thanks. That popped into my head as soon as I saw the thread title, but you saved me searching for it!

[KBeezie]

My unscientific approach is...if your only experience is noodler's or fpr flex, then basically don't press nearly as hard as those in any others, if you have to, it's too much.

Also if you're creating white in the bed of your nails with the pressure push back.... It's waaaay too much ;p

[Chrissy]

My unscientific approach is...if your only experience is noodler's or fpr flex, then basically don't press nearly as hard as those in any others, if you have to, it's too much.

Also if you're creating white in the bed of your nails with the pressure push back.... It's waaaay too much ;p
That sounds like a good approach. :)

[Richardtractorguy]

...How much separation force does it take to achieve maximum flex on a superflex nib and how wide is the tine separation?
How long is a piece of string? You'll need fewer variables.

Thanks Fred...just saw this has been discussed in much detail in 2015 by you and others!