...so I've been happily harping away with my new Thunderbird, coincidentally going through my free trial at Bluesharmonica.com over the previous month.

A few days ago, I decided to give the thing a quick clean, and I was shocked how much tarnish there was on the reedplates - so much so that the green discolouring had transferred to the wooden comb.

The site advocates tongue blocking, so that's what I've been trying - but it effectively quadruples my saliva output. Playing a low tuned harmonica, often outdoors in cold weather - I'm concerned that this excess moisture will shorten the lifespan of the instrument. The comb is highly lacquered along the mouthpiece edge, but not beneath the reedplates.

Is tarnish something I should be concerned about, and polish off regularly?

Should I maybe seal or treat the comb, or am I being too overprotective..?

IMO, you're being overly protective. Tarnish and wear (when primarily external) add character. There IS something to be said for taking care of/cleaning your harps, as gunk buildup is a definite issue; but as with most instruments, the true character of the instrument is developed from use. Discolorations to the covers and surface of the comb are to be expected to some extent. There is a point when the wear becomes damage, and the instrument must be repaired or replaced, but for harmonicas, this is usually the reed plates. Combs and covers can become problematic, but that usually takes a LONG time, and wooden combs are more susceptible to damaging wear than the covers or combs made from other materials. If your harp has quality steel covers and a solid ABS plastic or aluminum comb, you'll likely go through more reed plates than other parts, though your comb and covers will start to get a certain patina from all the use.

Adieu! (Or is that, "Adoughnt"?)

PCGuyIV