EDIT: Okay, let's start again.

I have a Sheaffer rollerball which needs some repairing. I have the body, assembly (?) and cap. But the thing is, when I put the body onto the assembly, and then pop the cap on, when I take the cap off, it brings the assembly with it. How do I put properly attach the body to the assembly?
Also, is the frontmost part of the assembly really separated from the main thing itself? See the second picture for more info.
And lastly, what model is this?

Thanks!

Well, it's a Sheaffer Javelin model, that much I know.
As for the other part of your question, I'm afraid I can't answer it. I got my Javelin rollerball from my parents (who got it in a secondhand store for me ) and the metal tube (what you call the "assembly") was stuck in the barrel when they bought it

I'm kind of curious as to why the pen needs the assembly part at all (I guess to avoid needing a spring???) edit: yes, there is a spring there!! Thanks for pointing it out, lancekatigbak Gotta stop posting early in the morning *and* late at night )

But for some reason, there's a spring in the barrel.

Oh yes, I see it now. There was some kind of crusty-looking gluey substance down there obscuring my view sans flashlight....

Anyway, back to the original question....
When I take my Javelin rollerball apart, the metal tube part (which the rubber grip covers) is attached to a threaded black plastic part... I honestly don't know if this is the same for other pens of this type as I said above, someone (perhaps my Dad?) tried to glue something together...and the pen works fine, so I didn't think twice about it.

Is it too much for me to ask you to take a picture of your pen disassembled?

I'll try to do this tomorrow---gotta run to work now!

Sorry for the delay; work has been kind of nuts lately....
Ok, not a great shot (the closeups turned out lousy), but here is the photo I took earlier today of my Sheaffer Javelin rollerball with cap off and section unscrewed:


There is a gap between the threaded part of the section and the rubberized gripping area, as you can see (hopefully) and there is dried glue in the gap. I don't know if this gap was originally there when the pen was made, but I suspect it wasn't. I am thinking that maybe the pen was broken when someone tried to pull the section off, rather than unscrewing it.

In any case, perhaps the solution to your pen problem is to unscrew part of the section that is currently in the barrel of your pen, and somehow attach it (glue) to the metal tube?

Hope this helps.

edit: I added a larger photo of the disassembled pen here:

Thanks for the photos!
However, my Javelin is missing the threaded section in both the barrel and the assembly. Is all hope lost for this pen?

You're welcome. Sorry to hear that your Javelin is missing its section. I guess there is zero chance it is still screwed into the barrel, but difficult to see?

The only reason I ask is because the used Javelin pen I got from my parents had glue on the area where the section was attached to the metal tube...

If you don't have a section, I don't know how the nose cone/metal tube/gripping area would stay attached to the barrel while you are writing (and also to keep the cap attached to the barrel when capped).... I suppose you could try masking tape on the metal tube to create a friction-fit for the barrel...Maybe someone else will come up with a

Hi

Looking closely (alas Lances pic is not very sharp): Lance has a short section lying on top of the barrel. There is sommething sticking out of the barrel

On Majas pic there is nothing sticking out of the barrel, but soemthing coming from the section with screwthread attached.
Assuming that Majas pen is the correct working version I concluded that the thing sticking from the barrel in Lances pen is the thread that has broken/come undone from the section. If I'm right Lance should be able to unscrew the thing from the barrel with some smal plyers with tissue to protect the pen.
If it really has broken of......


D.ick

D.ICK, YOU ARE A GENIUS!
It worked! In fact, i was able to do it by hand. Now, I just need to superglue it, and find a refill...