it's bad because there is excessive tine vibration under braking. i still have it because it's a frame built for 650c wheels and it's not easy to find a 650c carbon 1" threaded fork these days. and i'm too cheap to pay upwards of 1-200 dollars for one.

oh, and it's painted and polished to match the frame. and it's not one of my favorite bikes anyway. and no, i'm not going to go into WHY it's not a favorite...

Well, I went by VeloCult and talked to them about my desires and budget. Their recommendation:
- have a local frame builder make me a disc fork with height and rake identical to the existing fork, 1" threaded.
- get a TRP Spyre mechanical disc brake
- build a new front wheel and voila

So I'm going to call some local frame builders and see what this might entail.

Sift through the selection of used forks at Citybikes. See if there's something with the correct size steerer and heavy-ish blades (don't ask me how you would figure this out). Then have a framebuilder add a mount for a disk brake. It's got to be cheaper than a 100% custom fork.

Suggestion from out in left field: Bacchetta (the recumbent people) offer a steel fork with a 1" steerer and a disk mount: https://shop.bacchettabikes.com/parts...w-1-steer.html
It nominally fits a 26" wheel, but they say it's got enough room for a 700C. You'd still need to do a threadless conversion, but it might turn out cheaper.

Hey, that Bachetta fork doesn't look half bad. Aesthetically it would work better than the Nasbar fork, especially if I remove the canti studs. And it is pretty cheap.

Edit: in case anyone is looking at this fork, height is 382 mm (axle to crown), offset 40 mm, weight w/ 1" steerer uncut 2 lb 12 oz. So it should comfortably fit a 700C wheel w/ 25mm tire, while being 9 mm shorter and $45 cheaper than the Nashbar fork, but almost 13 oz heavier (less after the steerer is cut).

Checked around and the Portland custom fork prices I'm initially seeing are a fair bit higher than I expected. $380-500.

Yep, and that's before you factor in the new disc brake and front wheel and whatever other components you will need.

I bet the canti studs are welded on, so you'll need to use a saw and a file to remove them. Not a big deal, but something to think about if you eventually de-diskify the bike.

Vanity knows not reason :-)