I thought they use special tape for it.
On one of my accordions (Castagnari) they used two types of color as bellowtape.
Black and gold.
Link#2 gives you an idea how it looks like.
Link#3 gives you information to buy bellowtape.
Some instructions( also from link#3)
How to Apply New Bellows Tape
Use ordinary white glue for putting on bellows tape. The standard technique is to spread a bunch of the glue out on a board. Then lay the strips of tape on the board and press them onto the glue (with a piece of wax paper on top of the tape, to keep the glue from getting all over your hands). This gets just the right amount of glue on the tape. Then apply the tape to the bellows.
If you are using ribbed bellows tape, be sure that the diagonal ribbed pattern is going in the same direction from one fold to the next. The bellows need to be pressed while the tape dries (under quite a bit of pressure, e.g. at least 50 lb.). Put strips of wax paper between the bellows folds while the glue dries so that they do not stick together.
Use 3/4-inch wide tape unless you are putting new tape over the top of old bellows tape. In that case, use 1-inch tape.
That's right.
I have one Castagnari(D) now and the other one(C) I own was an older model. The D is a bit similar as the one, you see on the internet.
Both were tuned Cajun.
A few years ago I bought an accordion from Junior Martin and I'm very happy with that accordion and I hope to replace the other Castagnari also for a LA-made accordion.
The Castagnari-accordions are very good accordions, but the most LA-made accordions are better(imo) to play Cajun-music.
Hello..
The information you shared in the post related to the bellows is really very nice and useful to me as I was looking for such decoration ideas. I will follow such steps.
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Are you looking for the best flexible bellows | machine bellows .
Unless you're a builder, artist or an engineer draftsman, I wouldn't recommend trying to decorate something you want to have reppin' your songs. Know what I'm sayin'? It's kinda risky. Leave it to the pros...
i already build banjos and simple fiddles. i think i could pull this off well. i was thinking a bird outline to give the effect of it flapping its wings while you play.