"side Knock" Mechanism Of Rotring 900 Ballpoint Pen

[Rosso Corsa]

Hello to all,

I got a Rotring 900 "side knock" ballpoint pen and I would like to know how the internal mechanism works.

 

I was able to open the pen, but I did not find anywhere on internet an explanation regarding its internal structure, so at the moment not only I am not able to understand its mechanism, but also I do not understand if my pen is broken or not, and if some components are missing. I have not got a refill for this model, and I am not sure on what refill type is compliant to this model.

 

This ballpoint pen is one of the most original I ever saw, and its mechanism is quite original: the barrel is divided in two pieces, and the pen bends in the middle to push out the ballpoint tip.

 

I made some photos after disassembling it, in the end I found only 5 pieces:

1 and 2) the 2 halves of the barrel;

3) the front part, to be screwed with the front part of the barrel;

4) a very strange metal component having an almost conical shape;

5) a very small spring.

 

The metal component was inside the rear part of the barrel, free to move into it. Perhaps it could have to be connected to the spring, like in the photo, but I am absolutely not sure about that.

 

 

Does anyone know anything about this pen, and in particular what is its internal structure, how many components it has and how its mechanism works? Is my pen broken, are there missing parts? I was not able to find answers till now....

 

 

TY very much in advance!!!

 

 

Ciao

Mauro

[Steveg58]

Here's a page on the Rotring 900 mechanical pencil - perhaps the writer knows about the pen as well?

[MYU]

I have a pencil that functions in the same way -- you bend it to extend the lead. It's made by Artline.

 

While I can unscrew the front nose cone, this does not release the mechanism. I don't want to force it and break something. Anyway, since you mention you don't have a refill, then of course it will not work -- it must have a refill to function. I think it takes your standard Parker style refill, as rOtring was pretty consistent about that.

See Colorado Pen - Refills for rOtring.

Photo showing refill:

Edited June 19, 2018 by MYU

[stuck-in-time]

There were actually 2 versions of these Rotring 900 ballpoints (I'm talking about the mechanism here, not the finish/color). One takes a G2/Parker-style refill and use what I assume to be a traditional click action mechanism

 

I think it takes your standard Parker style refill, as rOtring was pretty consistent about that.

See Colorado Pen - Refills for rOtring.

Photo showing refill:

 

The other one, like yours, uses that very cool side-knock mechanism. I have one of these, and it's one of my favorite pens. The unique mechanism perfectly complements the pens extraordinary design. It adds that extra cool factor, I guess. But at the expense of refill capacity and the solidness of the pen (the bendy bit might have a tiny bit of play).

 

The side-knock pen uses a D1 refill, which is widely available. It's the same type Rotring uses on theil multi pens. If you're planning to get one, I highly recommend the Uni Jetstream D1 refills, very smooth writing and very good black color (if you want black ink that is).

 

Regarding the mechanism itself, I never opened mine since I'm afraid of breaking it, and apparently it's quite different from the mechanism of the pencil which is very similar to

I have a pencil that functions in the same way -- you bend it to extend the lead. It's made by Artline.

Nevertheless, I'd suggest putting the thing back together to avoid losing parts. I'd think that there wouldn't be any problem with it, since these pens are of exceptional build quality, and those parts aren't meant to be opened anyway. The pen can be loaded without opening anything.

 

Looking at your picture, though, I can see that you are missing a spring. There should be a spring between the front cap and the body of the pen. It's a common position for a spring, just like any other traditional click-action ballpoint pen, it keeps the refill inside the pen when it is retracted.

 

To differentiate the 2 types of mechanisms, the most telling clue if the joint of the "bendy" part that is located where the red ring is. On the traditional one, it's flush with the pen, while on the side-knock version, there is a slight notch to accommodate the bend. Other than that and the placement of the logo, the 2 are visually identical.

 

Pics here: http://bionicle123.pixnet.net/blog/post/28185474-rotring-900-%E7%AD%86-%E7%9A%84%E6%95%97%E5%AE%B6%E5%AF%AB%E7%9C%9F%E5%85%A8%E7%B4%80%E9%8C%84-3

 

Your picture of the inner working of the pen certainly intrigues me. I fully understand how the pencil version works, but now I'll be thinking of how the pen does... Hmm...

Edited June 19, 2018 by stuck-in-time

[Kodiac136]

I have a pencil that functions in the same way -- you bend it to extend the lead. It's made by Artline.

 

Not to derail the thread here, but what is this model of pencil? It is just beautiful.

[Rosso Corsa]

There were actually 2 versions of these Rotring 900 ballpoints (I'm talking about the mechanism here, not the finish/color). One takes a G2/Parker-style refill and use what I assume to be a traditional click action mechanism.....

 

.....

The other one, like yours, uses that very cool side-knock mechanism. I have one of these, and it's one of my favorite pens. The unique mechanism perfectly complements the pens extraordinary design. It adds that extra cool factor, I guess. But at the expense of refill capacity and the solidness of the pen (the bendy bit might have a tiny bit of play).

......

Regarding the mechanism itself, I never opened mine since I'm afraid of breaking it, and apparently it's quite different from the mechanism of the pencil which is very similar to

Nevertheless, I'd suggest putting the thing back together to avoid losing parts. I'd think that there wouldn't be any problem with it, since these pens are of exceptional build quality, and those parts aren't meant to be opened anyway. The pen can be loaded without opening anything.

.......

Looking at your picture, though, I can see that you are missing a spring. There should be a spring between the front cap and the body of the pen. It's a common position for a spring, just like any other traditional click-action ballpoint pen, it keeps the refill inside the pen when it is retracted.

.......

To differentiate the 2 types of mechanisms, the most telling clue if the joint of the "bendy" part that is located where the red ring is. On the traditional one, it's flush with the pen, while on the side-knock version, there is a slight notch to accommodate the bend. Other than that and the placement of the logo, the 2 are visually identical.

.......

Your picture of the inner working of the pen certainly intrigues me. I fully understand how the pencil version works, but now I'll be thinking of how the pen does... Hmm...

Thank you very much for your so detailed explanation!

 

You are right, there were two versions of this pen, this one and another, not so original.

 

Watching a photo of a spare tip sold in ebay I noted there a spring was included, and you gave me the confirmation of that. At least this component is missing.

 

I agree with you on the pen quality, it seems to be very high. The only part that can be easily unscrewed is the tip, for changing the refill. Thank you also for indicating the correct refill type, I shall buy one.

 

In my experience the 2 parts of the barrel can be separated quite easily, the rear part is screwed with the other just above the ring, as showed in my photos.I had to use a small tong for blocking the rotation between the two halves due to their connection. Of course I had to protect very carefully the surface of the barrel and the connecting "side knock" mechanism. But if your pen does not have any issues, pls do not take any risks and leave the pen assembled! We shall try to understand the mechanism using my already disassembled pen.

 

After having separated the two parts of the barrel, I found in the rear part of it only one piece, that little metallic part with an almost conic shape. Also a very small spring was inside the hollow cylinder of the front part of the barrel. the small conic component was free to move inside the rear part of the barrel.

I would like if it is the same in your model. I mean, if you shake the pen do you hear any rumors?

In my pen I heard the rumor made by that small metallic piece moving inside the rear part o the barrel.

 

Another mystery is the small spring: does it have to be connected to the metallic cone or not? Who can say? When I opened the pen they were separated...

 

Thank you a lot for your precious help!

 

Waiting for other details..

 

Ciao!

Mauro

Edited June 19, 2018 by Rosso Corsa

[Rosso Corsa]

Thank you very much to all you friends that are trying to help me.. Very appreciated!

 

Ciao

Mauro

[Algester]

whether or not the mechanism is different Tombow's Olno also uses the same thing

[MYU]

 

Not to derail the thread here, but what is this model of pencil? It is just beautiful.

 

Sorry for my late reply. It's an Artline mechanical pencil. Model number unknown. I contacted Artline and they weren't able to help me, as it was made for the Japan market. Apparently the company didn't really specialize in pencils, so this was more of a one-off.

[toymachine]

Been looking all over for a replacement spring for my Rotring 900 ballpoint. Any ideas? Any dimensions, if you have one?

[Algester]

Been looking all over for a replacement spring for my Rotring 900 ballpoint. Any ideas? Any dimensions, if you have one?

if they use Parker refills you are probably in luck if you can get a Pentel Energel you could potentially use the spring there else Tombow's Aquagel RT pens

 

this is what I used on my Staedtler Cement to convert it to a BP from an MP I just need to find those Uniball Parker shaped refills in my country

Edited September 26, 2019 by Algester

[toymachine]

if they use Parker refills you are probably in luck if you can get a Pentel Energel you could potentially use the spring there else Tombow's Aquagel RT pens

 

this is what I used on my Staedtler Cement to convert it to a BP from an MP I just need to find those Uniball Parker shaped refills in my country

Sadly no. The Rotring 900 ballpoint uses a D1. There appears to be a spring on the top of the cone piece that is used for the body knock mechanism. I have the 900 bp and it's in amazing shape, but I now know the spring is missing (based on the images above)

Edited September 28, 2019 by toymachine

[Algester]

Sadly no. The Rotring 900 ballpoint uses a D1. There appears to be a spring on the top of the cone piece that is used for the body knock mechanism. I have the 900 bp and it's in amazing shape, but I now know the spring is missing (based on the images above)

all the samples I saw were Parker based refils...ohh well it seems what ever you are missing is also a bit too small

[Honeybadgers]

Well thanks you just made me realize the 900 comes in a fountain pen, and I just spent $80 on a NOS one.

 

I wish the 600 FP wasn't such a complete and total ripoff. Why is anyone paying $200 for a steel nib version and $400-600 for a gold nib one. I'd drop $100 on a steel one, $200 on gold at most.

Edited October 4, 2019 by Honeybadgers

[toymachine]

all the samples I saw were Parker based refils...ohh well it seems what ever you are missing is also a bit too small

Yes, the parker refill one is the top button, and the D1 is the side-knock. Both are very nice!