Repair to HMV Model 2, 25 Zonophone HAO etc. horn fastener

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Ivor-Duncombe
Victor Jr
Posts: 33
Joined: Wed Jan 22, 2014 4:29 pm

Repair to HMV Model 2, 25 Zonophone HAO etc. horn fastener

Post by Ivor-Duncombe »

Having got the horn back into shape I felt quite entitled to modify it any way I chose.

I drilled out he threaded old-fashioned equivalent of an "anchor nut" in the horn to the right size to accept a modern 6mm anchor nut. Now you may know what an anchor nut is, but someone else may be reading this who doesn't know what it is. Anyway if you don't have an anchor nut rivetter in your workshop, then you should seriously think about getting one with a few of each size anchor nut. The anchor nut is a cylindrical fitting with a flange at one end (similar in principle to the flange of a pop rivet.The anchor nut principle is much the same as pop riveting, except there is no "nail" to pull on to expand the rivet. Instead one screws a 6mm (or other metric size) pulling rod, which is screwed into the anchor being fitted.

One then pushes the thus fitted anchor through a washer which fits the anchor nut well and stops at the flange. The anchor nut is pushed into the drilled hole from the outside of the horn neck and held there whilst another washer is fitted onto the anchor nut from the inside of the horn neck (using long-nose pliers). One then squeezes the anchor nut riveter handles together and the anchor nut shortens and swells in the hole puling both washes snugly up hard against the inside and outside of the horn. One then relieves pressure on the riveter handles and unscrews the anchor nut puller from the anchor nut. Most of the body of the swollen anchor nut is inside the horn and on the outside one can only see the anchor nut flange, outer washer and a recessed hole with a 6mm thread in it. Taking more liberty I found a knob with a shank I could tap down to M6 and did just that. The knob is now screwed in firmly holds the horn firmly into the original the supporting elbow as it should. It looks the part and holds the horn very firmly.

A picture is worth a thousand words.........

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