Parker 21 Super Vs Parker 51 Demi

[Ispriluc]

I`ve been trying to fully understand the differences between the 21 super and 51. I found a review by tonybelding and a post by Jerome Tarshis, both excellent, but i still have some questions. I hope somebody will be able to help me.

Will the parts (cap, hood, barrel, clutch ring and metal housing of the filler) of a 51 demi fit on a 21 super? The pens seem to have the same dimensions in some of the pictures i`ve seen so far.

Is the 21 super identical to the 51 demi under the hood?

The nib of the 21 super is the exact same octanium nib found on the 51 special?

 

Thank you all.

[richardandtracy]

As to the question about the Ocatnium nib, It appears that the P51S Octanium nib & P21S nib are one and the same item.

 

I do not know the answer to any of your other questions. Sorry. :embarrassed_smile: However, I'll make an effort at trying to work out an answer based on what I do know...

My P21S cap uses a finger clutch on the hood, and the 'clutch ring' is flush, not operating like a P51 clutch at all.

The cap is different, having a stamped P45 style clip, recessed clip locator in the barrel body and metal jewel nut, so I'd be surprised if any parts were to be interchangable with any P51 bits.

I don't have a Demi, but the hood on my P21S is shorter & steeper than my full size P51 Aeros, so interchangability of parts is unlikely.

The barrel threads are very short, so even if the same thread it's unlikely to fit on a demi connector due to thread engagement being too long.

 

However - the solution may be to try it out to find out the answers for certain.

 

Regards,

 

Richard.

[thaugen]

I've owned both and the 21 super is about the same size as a standard Parker 51. The Parker 51 demi aerometric has a smaller barrel and cap. I don't think any of the parts would be interchangeable between the two, except maybe the nibs (21 octanium, 51 demi gold), feeder and collector.

[Ispriluc]

It appears that the P51S Octanium nib & P21S nib are one and the same item.

 

One down, two to go. Thank you!

 

I've owned both and the 21 super is about the same size as a standard Parker 51. The Parker 51 demi aerometric has a smaller barrel and cap.

 

In the review i mentioned above, the pictures tell me that the 21 super is almost the exact same size as the 51 demi.

[mitto]

The barrels, hoods, connectors and collectors are Interchangeble on 51 aero demi and 21 Super. The cap of 21S perfectly fits the Demi. The cap of demi fits the 21S but does not sits as deep as should be.

 

Reading this thread may be useful.

 

https://www.fountainpennetwork.com/forum/topic/297549-parker-51/

[FarmBoy]

I seem to be in the minority in my opinion, but the barrel on a 21 Super and a 51 Demi are not the same diameter. The threads to the connector are the same and thus both will thread onto the opposite pen. The caps are not the same diameter either. The 21 Super cap is larger and will fit on either barrel and will be somewhat loose on the 51 Demi barrel. The 51 Demi cap will not fit correctly on a 21 Super.

 

If it matters, Parker listed them with different part numbers. Want to make it more complicated? Throw in the 41s.

 

Parts for 21 Supers and 51 Demis are not in short supply. I will admit to not understanding the need to mix the parts.

 

FB

[pajaro]

Maybe trying to make a sleeper motivates wanting to mix the parts. I have been tempted to put a P51 gold nib in a P21 super. Too much trouble, and the P51s are too nice to cannibalize.

 

If you screw the P21 Super section into the 51 Demi barrel, it screws down. Demi cap does not fit onto P21 Super section -- clutch ring is too big. P21 Super cap does fit onto this Frankenstrosity.

 

If you screw the demi section into the P21 Super barrel, it screws in, but not all the way, and threads on the 51 Demi section can be seen. Demi cap kinda sorta goes on, but the P21 Super cap is loose and will not stay on. Like a palmetto bug with a grasshopper head.

 

I think I tested this foolishness in another thread. There might be a very small amount of usefulness to this if you have a broken pen and are trying to cobble something together if you have no other pen and a lot of parts.

 

If you want to fool around with something, why not try to make a P51 Clear Demonstrator out of P51 and Ariel Kullock parts. A great sleeper that seems to get some collectors riled up. Better if it's a Vac model. More educational about how that filler works.

[Ispriluc]

.

Edited September 30, 2015 by Ispriluc

[Ispriluc]

What a great community this is! It's been almost five years since I asked this question, the thread comes back up now and I'm still around to read the replies. It's sad that I don`t remember why I was so interested in the parts of the 21 super and the 51 demi.

I learned a lot in the meantime...never owned a 21 super or a 51 demi, but several 51`s passed through my hands and I still use one every day at work.

All the best, everybody!

Edited September 30, 2015 by Ispriluc

[FarmBoy]

Maybe trying to make a sleeper motivates wanting to mix the parts. I have been tempted to put a P51 gold nib in a P21 super. Too much trouble, and the P51s are too nice to cannibalize.

 

If you screw the P21 Super section into the 51 Demi barrel, it screws down. Demi cap does not fit onto P21 Super section -- clutch ring is too big. P21 Super cap does fit onto this Frankenstrosity.

 

If you screw the demi section into the P21 Super barrel, it screws in, but not all the way, and threads on the 51 Demi section can be seen. Demi cap kinda sorta goes on, but the P21 Super cap is loose and will not stay on. Like a palmetto bug with a grasshopper head.

 

I think I tested this foolishness in another thread. There might be a very small amount of usefulness to this if you have a broken pen and are trying to cobble something together if you have no other pen and a lot of parts.

 

If you want to fool around with something, why not try to make a P51 Clear Demonstrator out of P51 and Ariel Kullock parts. A great sleeper that seems to get some collectors riled up. Better if it's a Vac model. More educational about how that filler works.

We seem to be in agreement and we seem to be in the minority regarding if the barrels and caps will interchange.

 

I have a different proposal.

 

Lets pretend someone sends a 51 Demi in for repair and that the barrel is cracked. The repair person fits it with a barrel from a 21 Super and calls it a good repair.

 

Q: Would we read about an unscrupulous repair person on FPN that substituted a 21 Super barrel onto a 51 Demi?

[pajaro]

I think a color difference between the Super 21 barrel and the 51 Demi section might be noticed if the owner were conscious. In my last comparison I used a Teal 51 Demi and a blue Super 21, both pens NOS. The colors are close, but I can tell the difference. The repairer might get away with this on a black 51 Demi, but the other colors are way off.

 

I think the nibs are about the only thing that are reasonably interchangeable. As long as parts for the Super 21 and for the 51 Demi are available, this falls into the realm of something you experiment with as a demonstration. If some repair person reads this and pulls a fast one without getting the pen owner's approval, that is skullduggery. Someday in the future it might become an acceptable practice if the parts availability dries up.

 

The 51 was my first good pen. I hold it to be the best pen there is. I might have used Kullock parts to put a little color into my 51 holdings, but I draw the line at putting 21 parts into any 51. Even the nibs. If they were in a 21, then putatively they are contamination. I have no Demis with Octanium nibs. I don't want any.

 

Midnight blue forever!

[jmnav]

This is an old thread but, since it's still the first one some famed search engine offres and it doesn't answer the question in full, here come my two cents.

 

Yesterday I had the chance to live-compare all these models (it is just unluck that I found this thread today instead of some two days ago, since I could have payed more attention to details)...

 

• Vacu demis are shorter than Aero demis, I can't remember if thinner too, but possibly (from now on, I'll just compare super 21 to aero demis).
• For all that I know, super 21 octanium nibs are the same than those from 51 special (and possibly their collector too).
• 51 demi is not only shorter but also thinner than 51 "standard".
• Super 21 is the same thickness that 51 "standard" but same length than 51 demi. This means you can use a 51 "standard" cap on a super 21 but not the other way around (it almost fits, but not quite so).
• 51 plastic is PMMA (lucite) while super 21 is polystyrene.

 

I think that's all.

[inkstainedruth]

I have a bunch of 51s (both Aerometric -- including at least one Demi -- and Vac models), one 51 Special, one 21 (regular I think) and one 41.

I've never been able to adequately figure out how a 21 Special fits in to the mix.

The fast and dirty distinctions:

51s -- gold nibs, lucite bodies, and either a Vac fill system (earlier) with the plunger or the squeeze bar sac sleeve.

51 Specials -- Octanium nib, Lucite barrel, hoop filler.

41s -- "pretty" colors (like pink, turquoise and light grey), Octanium nib, cheaper grade plastic barrel, hoop filler.

"standard" 21s -- Octanium nib, cheaper grade plastic barrel, hoop filler.

The best that I've been able to determine about Super 21s is that they were (maybe) made from leftover stock when the 41 was an unsuccessful model for Parker (my *personal* surmise has been that women were going "Naah, I'll save my money up and buy a Demi 51 instead if it's all the same to you..." ). But I can't figure out what makes a pen a Super 21 vs. a "regular" 21....

Ruth Morrisson aka inkstainedruth

[FarmBoy]

This is an old thread but, since it's still the first one some famed search engine offres and it doesn't answer the question in full, here come my two cents.

 

Yesterday I had the chance to live-compare all these models (it is just unluck that I found this thread today instead of some two days ago, since I could have payed more attention to details)...

 

• Vacu demis are shorter than Aero demis, I can't remember if thinner too, but possibly (from now on, I'll just compare super 21 to aero demis).
• For all that I know, super 21 octanium nibs are the same than those from 51 special (and possibly their collector too).
• 51 demi is not only shorter but also thinner than 51 "standard".
• Super 21 is the same thickness that 51 "standard" but same length than 51 demi. This means you can use a 51 "standard" cap on a super 21 but not the other way around (it almost fits, but not quite so).
• 51 plastic is PMMA (lucite) while super 21 is polystyrene.

 

I think that's all.

Vac Demis are the same diameter as Vac Standards. The Vac Demi cap is shorted than a standard cap.

Super 21 nibs and 51 Special nibs and 41 nibs are the same.

Correct.

Super 21 parts don't fit on 51s.

The 21 is not polystyrene.

[jmnav]

I can't figure out what makes a pen a Super 21 vs. a "regular" 21....

 

On top of aesthetical differences (different cap and clip, mainly), the critical difference is the nib: the 21 "standard" also has a standard, "flat" nib, only partially hooded, and a standard feed. The Super has the 51 cilindrical nib and colector. You can set apart with easy just looking at the back of the nib: the "vent" on the Special is just like that of the 51, while the 21 "standard" is wider.

[inkstainedruth]

 

On top of aesthetical differences (different cap and clip, mainly), the critical difference is the nib: the 21 "standard" also has a standard, "flat" nib, only partially hooded, and a standard feed. The Super has the 51 cilindrical nib and colector. You can set apart with easy just looking at the back of the nib: the "vent" on the Special is just like that of the 51, while the 21 "standard" is wider.

 

Thanks. Can you post pix showing the difference? I'm not sure I'm getting it straight in my head.

Ruth Morrisson aka inkstainedruth

[jmnav]

This is from a French forum: http://www.stylo-plume.org/viewtopic.php?f=29&t=10172 (super on the sides, standard in center)

 

...and here, a 21 dissassembly https://imgur.com/a/fbdLH#QFV8qH3 Look how there's no trace of tubular nib or collector, but a standard "flat" nib plus feed.

Edited July 17, 2018 by jmnav

[mitto]

Thanks. Can you post pix showing the difference? I'm not sure I'm getting it straight in my head.

Ruth Morrisson aka inkstainedruth

P21 Standars.

 

https://m.ebay.com/itm/NICE-VINTAGE-1950s-BLACK-PARKER-21-SPECIAL-FOUNTAIN-PEN-RESTORED-FINE-NIB/323342439978?hash=item4b48b6162a:g:dVAAAOSwYUdbRNBY&_trkparms=gclientid%3DxxXvldnHzBWdFnRzXKIVu1mHd8xf-AFtWA0tJfEHFwJzCWPHH9RPiVcnP-_RCBFX&_trksid=p2489528.m4335.l8656

 

P21 Super.

 

 

https://m.ebay.com/itm/Parker-Super-21-Fountain-Pen-Red-Fine-Nib-1970s-New-Old-Stock/112550681466?hash=item1a348b1b7a:g:2AoAAOSwC6dZrEpP

[inkstainedruth]

Okay, I think I see the differences (although I had to open one of the links in a new window in order to do a side by side inspection).

Thanks, mitto! This was helpful.

Ruth Morrisson aka inkstainedruth