Hi Be careful what you put around the burner it needs to be heat resistant, you do not want a fire in your loco
Age is only a state of mind, keep the mind active and enjoy life
Most burner silencers I've seen published consist of a "tent" of fine stainless steel mesh wrapped loosely around the burner, in such a way that the bottom of the burner (where the flame isn't) sits against the inside of the tube of the mesh, which is a larger diameter than the burner by maybe 70% or so. The advantage of this is twofold. First, the mesh interrupts the airflow which is what contributes to the whistling, and also the the mesh becomes a radiant heat source, adding to the efficiency of the burner so you use less gas, which also contributes to a quieter burner (and longer run times.) As for where you get the stainless steel mesh, I'm not sure. I'd try the usual suspects like Micro-Mark or perhaps Small Parts.
I have not done this kind of modification myself as yet, but I've got two Accucraft Rubys (Rubies?) which are slated to get this treatment at such time as I actually have the opportunity to run live steam on a regular basis again. (Andy will be in elementary school in 5 years...) I have heard the difference when these "silencers" are installed, and it's dramatic--well worth the effort.
I don't remember if such a device has ever been written up in GR--perhaps Rene can check--but I know they've been covered in Steam in the Garden fairly often. An e-mail to Ron Brown (SitG's editor) might provide an exact issue.
Later,
K
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