Converter for Caran d’Ache Fluo 849?

[FP fan]

I purchased a set of Caran d’Ache fluo 849 fountain pens some time back, but find that the Caran d’Ache converters purchased for use with these do not actually fit. They got stuck inside and were really difficult to remove without damaging the converters (and maybe the pens?).  I managed to use a Pilot Conn50 converter, and that fits fine with most of the others. 
 

However, in the first pen I used, even that will not work.  It’s an EF nib (I suppose I could try swapping the nibs between the pens, when not in use?). I refilled a J Herbin cartridge with the ink I wanted, but with the EF nib, that put a lot of random ink blobs down on the page. Not good.

 

The Caran d’Ache standard international (short) ink cartridge seems to work better, with a snug fit, but I only have that in idyllic blue, which is not great for an EF pen. Any tips? I use mainly bottled ink. I dislike plastic cartridges and refilling plastic cartridges. Oh, and the cheap J Herbin converters do not work with this pen either.

The biggest disappointment to me was that having spent nearly £50 on the pen, and £7.50 on a dedicated converter, it didn’t fit...

 

 

[FP fan]

[ballboy]

Cd'A converters usually have a thread at the font for screw-fitting into the nib section; check inside the nib section to see if there are any threads for such a fitting. If there are none, a smooth push-fit type converter might be available from Cd'A or a standard international converter with no ring at the front, just plastic like a basic Schmitt might fit in more successfully.