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So, based on my night last night, does it make sense to get longer bell screws and drill into the tenon, in order to make the bell a bit more snug? It comes loose quite easily right now, it's the Kanstul repro bell for the Martin.

Since the question involves a Martin - the original bell tenon on Martins is thin, and the bell front, which is big and heavy - can be easily pulled out - true of the bell-fronts, and true of the repro bells too.

I solved this problem by trading out the bell screws for Conn style bell screws, which have a machined tip or "nipple" on the end - and carefully drilling out an appropriately sized hole in the bell tenon. The original Martin bell screws are blunt and while they have fancier knurling it's best to send a non-thread tip into the holes on the tenon. The Conns are the same thread.

Walter Sear solved this problem years ago by machining a groove in the bell tenon to give the screws a slot to grip. He did this on the dePrins bell-front models (rare as hen's teeth to find these days).

Martin kept their bell collar & tenon thin for a reason - less metal on the collar, better response. King did the same. Martin bell collars are pretty large, and because they are thin they tend to get "out of round" easily - comes with the territory on this horn. I've been playing a Martin since the 1970s and had the bell trued several times. One little knock and it's no longer round. My guess is the bell tenon is close to thickness of the bell's material itself. Martins had pretty thick bells - which is why it's nearly impossible to overblow the horn.

The Kanstul/Stofer bell is a huge improvement to this instrument, and I would not advise mucking around with the bell tenon - Stofer and Kanstul wisely used a thickness that replicates Martin's original, and the proof is in the performance.

Change out the bell screws and drill the holes. Either have a repairman do it, or if you are skilled and have a pin punch, sharp drills and a drill gauge (check the bell screw for exact hole size) and do it yourself.

I also like a dab of blue Thread locker on those screws - at $12 a piece it's a pain to lose them.

Mark Heter

I've drilled holes through the tenon on my helicon that are slightly larger than the 'pilots' on my bell screws.

Ah....confirmation that my idea isn't so whackjob after all. Thanks, Mark and Dan! And Ian and bloke too, for that matter. I just choose to not follow your ideas....

I don't want to drop another grand for a replacement bell. I didn't get this one direct, it came with the horn from a private seller.