Kim Jumbo has been reviewed here thoroughly by other members, so I will not go into the details about the pen itself.
I bought a Kim Jumbo with a flex steel nib from a fellow FPN member S-K a few months ago, he customized the ebonite feed and the steel nib. I travel a lot on work and found it hard to practice Copperplate with a dip nib, and hence was searching for something that will help me practice forms while I travel. Unfortunately, I haven't been able to use the pen until now and as you can see from the writing sample I need a lot of practice!
I do not have any vintage or modern flex pens, so comparisons were not possible. As expected, this steel nib is definitely not as easy to flex as the dip nibs that I use. The tines do take time to settle back once the pressure is released. As long as I do not exert more than the threshold, I have not had any railroading issues with this pen. It lays down a wet line and I have tried with the following locally available paper,
- Bilt 100 GSM Executive Bond: holds well and no seeping or feathering
- Bilt 70 GSM: Holds well but slight feathering
- J&K 75 GSM Copier: Seep through and feathers when I rewrite
- HP 75 GSM: Seep through and constant feathering
The pen is huge (as mentioned in the other reviews) and can hold a lot of ink, but as I've adjusted it for a wet flow I've gone through four refills in the last week.
I have only tested it with Bril Black and a mixture of Bril Black and Camlin Royal Blue. So I'm unsure if it is the ink that is causing the problem.
The nib and feed are great and S-K wrote to me about being very cautious with replacing them. I must confess that in better hands, the result of the flex might be far greater.
PS: Mods, please move the post if this is not the approapriate section.