As stared by onepuff,
Modern 400 nibs and 600 semi-nail nibs are a waste of money....unless all you want is butter smooth.
They are just semi-nails; like a P-75's nib....but blobbier.
Made so, because of the hamfisted ball point and roller ball users, don't have the three minutes to learn how to hold a fountain pen; and one must not frighten them. the buyers off by putting a small instruction book in the fountain pen box.
They are blobby, 1/2 size or more wider ( I have a modern MB B nib that is BB.).
A K nib, ie KM, is a kuggle/ball nib. It was designed for folks that liked to hold their fountain pen like a pencil...pre-ball point. In Pelikan they had a flattish bottom...ie stubbish, with more tipping on the tip and the upper side of a nib...sort of a reverse of the American Bump under. You could hold the pen high or low. Holding it low like a regular fountain pen gave you that flat crisp line of the flattened less tipping.
The modern 400/600 nib has a double kuggle/ball tipping. = fat and blobby. Semi-nail not 'true' regular flex.
My '90's nibs are 'true' regular flex, a 400, two Celebery pens; one in gold-one in steel, both =. All three nibs are = very good. 4 of the 6 200's nibs that I transmailed were as good as that. 2 were a hair less, the same good as a -50's-60's 120's true regular flex nib.
Opened my eyes to the fine 200's nib.
The gold nibs of the '50-60's...called pre '66 when Pelikan stopped making classic nibbed 400nn's.. unless marked D=daur which is a nail/manifold nib, are semi-flex or flexi/maxi-semi-flex...in most wanted nibs with a tad of flex.
A good steel 200 or 120's nib or true 14K regular flex nib are the good basis for for comparing nibs of some flex. A modern semi-nail is not.
If you mash a 'true' regular flex it will spread it's tines 3 X a light down stroke.
Semi-flex does that at half the pressure.
'Flexi'/maxi-semi-flex ** with half of that or 1/4th of the pressure needed of a true regular flex to make a line #X a light down stroke.
In all three of these nib flex sets, only spread their tines 3 X a light down stroke...IMO they are not "Flex" nibs; which spread tines 4-5-6 or even 7 X a light down stroke, with progressively less pressure.
Easy Full flex-18th that of a true regular flex.
Wet Noodle 1/16th.
Weak Kneed Wet Noodles even less.
**Maxi-semi-flex ...Having an Easy Full Flex nib, I had a Rupp nib that was a class higher in the flex class than my semi-flex. For three days I rand around saying wow that certainly is a maxi-semi-flex.
Three days later I realized it was one of those 'flexi' nibs that many talked about, but none described. I there for describe it. It does help to have a semi-flex to know for sure. But does give an idea of what a 'flexi' nib is.
Rick I believe said the 400NN's are 'maxi-semi-flex'. Other's say the latter 400nn's are only or can be semi-flex.
So it's a bit of a crapshoot if your nib will be semi-flex or 'flexi'...back in the day you went to the corner pens shop and tried the nibs out...taking a semi-flex or 'flexi' as you wished. Now it's luck or buying from some one who knows the difference.
My 500 (51-54) a fancied up 400 with rolled gold cap and piston cap, is a 'flexi' OBB with a 30 degree grind. My 'flexi' 400nn from 1956...a rare 400nn...it had a friction fit feed, is a @ 15 degree OF.
My 400N is a semi-flex B.
My two 140 nibs OB&OF are semi-flex....but they have a smaller nib, that looks a bit dorky in a 200/400.
I do like semi-flex having @ 26, like the 'flexi' nibs too having @14.
Unless left handed I advise against modern oblique nibs....even in true regular flex.
Left handers can depending on which way they write have lots of trouble with vintage German oblique nibs which many have some flex.....I do have a nail Lamy 27 OM...so it's not all.
Oblique is good for those who cant their nibs also.
Normally I don't cant my nibs unless I have an oblique in my hand.
The Germans seem to have the patent on that Oblique nibs with some flex;....in the US went nail-stubb early in the '30's at least if not before. I don't know enough about British pens to know if they had oblique nibs....but in the six weeks I learned about and chased Swan nib so slowly I never caught one; I don't remember reading about Swan nib obliques. Swan had a very nice variety of nibs from regular flex to 'flexi' to perhaps Easy Full flex.
I am very lucky...in skill had nothing to do with it that I have both @ 15&30 degree cuts in OBB, OB, OM and OF nibs. That makes a difference to the patterns.
A stub or a cursive italic is max line variation always. (stated by a fine poster...a grand description)
Semi-flex or 'flexi' oblique nibs are some line variation with max on demand; to go with a much softer ride.
Zepp, vintage/used 400's be that the '83-97 or the '50-65 is what you need rather than throwing your money away on a semi-nail.
I recommend either buying a 400 vintage nib from Rick Propas in the states or Penboard.de in Germany. I'd suggest a semi-flex so you can slowly lighten your Hand naturally, so you would be ready for a 'flexi'/maxi-semi-flex some 3-6 months later.
A B or an OB would be good in a spare nib or in a 140. It is a nice writing nib, more like a M-B....not the fat blobby B signature nib of a modern 400/600.
I have my 400N's B nib in my 605 in my desk stand.
Edited by Bo Bo Olson, 18 May 2014 - 16:16.