Expanding bottom bow joint

Repair and modification discussion
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roweenie
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Expanding bottom bow joint

Post by roweenie »

A question for the pros:

Is there a method that one can use to expand the large end of a bottom bow to accept a slightly larger bell tail and ferrule?

The difference in diameters is about an eighth to three sixteenths of an inch, maybe too much?
"Even a broken clock is right twice a day".
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roweenie
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Re: Expanding bottom bow joint

Post by roweenie »

Thanks bloke - on to plan "B" :tuba:
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roweenie
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Re: Expanding bottom bow joint

Post by roweenie »

That's an intriguing idea, KT, but I don't have the facilities to make a ferrule that size.

It would be really cool if there were some sort of "data bank" of the measurements of different available bells - maybe there's one already in production that would "fill the bill" of what I'm looking for........?
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Dan Schultz
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Re: Expanding bottom bow joint

Post by Dan Schultz »

I have one of those small open-ended rolling mills. I think I could cut a long ferrule from an old bell stem that's rather thick and expand one end by thinning the material on that end. I've made ferrules larger this way but not attempted to make just one end bigger. I'll fiddle with it when I get some of the current stuff off my bench.
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Ken Herrick
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Re: Expanding bottom bow joint

Post by Ken Herrick »

It isn't that hard! Visualise things a bit. Something needs to be smaller and the other needs to be bigger.

Required tools - a torch and something like a Dremel.
I won't go too far now as I have been thinking and drinking but will give more detail here or by PM or email if you want more info.
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