I am going to be making and selling gourd banjos. One person suggested to put some kind of sealer on the inside of the gourd to keep it from cracking. Is this really necessary? I get very thick walled gourds from Welburn Gourd Farm.
I don't know about cracking, but I had an issue with mold. I sprayed a layer of Kilz after using a mold killer, problem never returned. I posted a similar question a few years ago and got 20 or so different opinions so brace yourself.
I ran across a nice (but kinda small) gourd for $4 at a flea market Saturday and started on my first gourd banjo.
I have no Idea if it was a great idea, but it was pretty fuzzy after I cleaned it out so I just worked wood glue into the inside of it with my fingers then wiped it out with a rag. Seemed to set up to a hard smooth finish for the most part.
I have never had a problem with gourds from Welburn. Clean it out well and enjoy. A++
You don't need a sealer, but sometimes you might need structural support, which can be done with fiberglass and epoxy. Also, I have heard that thin shelled gourds tend to sound better.
I'm growing my own gourds now.
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