well, my method sucks apparently.
Lesson one- get the right materials for the job.
Toilet cleaner with 25% hydrochloric acid content has not nearly enough chomp, fast enough, into 4130 chromoly. Because I had to leave the metal so long in the solution, the acid resistant varnish capitulated and vanished. Vanishing varnish:jerkit:.
So, I'm going to let the air get at both the varnish and the hydrochloric to 'thicken' them up a bit. Then I'll try again. I'll also let the varnish 'set' for awhile before I throw the steel into the acid, and apply a second coat. After a 24 hour soak, there was a noticeable bite into the steel, but not as much as I was hoping for. I may have to double the soak time and reapply the varnish every day to get the effect I want. Or maybe through trial and error I'll discover something even cooler than what I had in mind
I'm still working on the sample steel, and if I can't either get this to work the way I'm doing it, or can't find the ferric chloride or straight up acid I need, then I can always leave the ferrule shiny or carve into it with my dremel. I should still look into bluing, too.
In either event, I expect the blades to return relatively soon and totally want to have this ferrule thing figured out by then.
But in the mean time, I've started another knife which will be a personal sized symmetrical dagger. That should be fun

No really

My brother was watching me file the teeth off a file with a file today and was like, 'WTF?'. I had some fun with him, kind of like the 'sky hook' joke. Anyway, I'm really happy with the design and feel like it flowed properly. Mentally preparing the procedure is actually almost as much fun as putting the tools to work.
I'll bet the biggest challenge for those who make knives for a living is making knives that have no appeal to them, but are made to someone else's spec. The joy of discovering a new design out of your very own brain, and then translating that into reality is really addictive. If I had all the power tools so I could make all the designs I've thought up over the years in a speedy manner, I'd have a lot of ugly knives. Who knows? Maybe after all this, I'll have a couple of ugly knives. But at least I'll have made all my mistakes nice, and slow

That way maybe I'll remember em.