*** We no longer officially recognize Con-70 / Con-40 as converter for Eureka fountain pen models.
We only officially accept Eureka ultem ink cartridge as ink storage device for our pens.
1. when installing / removing, give a bit of rotation
2. (below picture) if ink is on the outside wall of Con-70, wipe it clean, then install.
otherwise, the ink will be pushed out and contaminate thread area (This is not leaking)
similarly, inside wall of grip section must be clean as well.
3. if there's a real leakage, then all converter ink will be leaked out from the nib area within minutes.
so please evaluate your situation correctly.
4. If you want zero contamination, do not remove the con-70.
just keep in in there. frequent installation / removal will lead to contamination, unless you clean all sealing surfaces (converter outer wall & grip inside wall)
5. if you give it a spin while installing / removing the converter, then the parting line (seen in the 3rd picture) will disappear eventually.
6. This was designed intentionally, to achieve maximum durability for grip, feed, etc.
so any design change is not possible.
This design allows wall thickness of all related parts by almost 2 times, so very good durability.
*** 7. If all efforts fail for some unknown reason, as a final resort,
put some silicone grease at Con-70's sealing area (Con-70's outside wall @ frontal area).
Only small amount is needed.
Use the pen without removing the converter. just keep it in there, unless it is required.
this will seal the converter 100%, in all cases.
*all newer pens have additional O-ring installed onto the tail of the ebonite feeder.
O-ring is not absolutely necessary, but if you want secondary protection O-ring can be purchased @ "Shop(Parts)" category. the O-ring can be added to all 5th gen ebonite feeder products.