Originally posted by webmonk
<br />So long story short...
Problem: Loose rings.
Solution: Press harder. (It's worked at least once!)
Of course this is the right solution... But here are a couple of additional thoughts/suggestions. For nomenclature: I'll refer to a platinum kit with gold trim. The outer ring is part of the fitting, then comes the gold ring, then another platinum ring.
The bands are just stacked. Before you assemble a kit, check and see if the gold band turns. If it does at that point, use a tube slightly larger that the proper one, or a drilled wood block, and press the platinum ring on. Or use a spare tube of the right size with e slot sawn in about 1/2" which allows you to pull it off again easily. If you can't stop the spinning then, get the part replaced.
When you use a finished barrel to press the platinum ring on, you are taking a chance, because now your pen barrel takes the full force - it becomes part of the press... not always a good idea! It's better to disassemble, correct the part, and reassemble. When you disassemble, the impact of the hammer you use will usually make the platinum ring move up, even on a fitting where it did NOT turn before. Which will make the gold band spin... so always check before reassembling!
Disassembling is easy - unless you have an uncured finish. To protect the cap barrel from the clip, slide the plastic bung that many kit fountainpen nibs are protected with for shipping over the clip so it will not mar the finish as it slides up.