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Chu Berry Conn Identification/Spot Plating
Q. I have two questions for you. First, what are the serial numbers for a tenor Chu Berry? Second, I took your advice (from some time back) and bought one of those  portable “Caswell” silver plating kits. I tried touching up some wear on the palm keys but had no success on plating. Any hints or suggestions?

P.S. Loved that special you did on the Yanagisawa factory!


A. Good to hear from you again. Thanks for the kind words about our work on the site. We are fortunate to have good friends like you all over the world. The Yani article was the result of one of those relationships.

The Chu run starts about 140k, or roughly with 1925 production. It runs to 239,999, though in the tenors some consider the transitionals up to 259,999 to be Chus, as well. As a practical matter, the horns from about 1923 & up are substantially the same. The significant design changes that occurred with the instruments often called ‘pre Chu’ are beefier keywork & set screws to hold the adjustments on the pivot screws. In 1925 Conn went to the knurled G# and a sleeker, ‘sculptured’ set of touches for the palm keys. Those 1925 cosmetic changes are the true demarcation line to the official Chu tenors. All the old Conn tenors are wonderful instruments, even the W.W.I era instruments
with soldered tone holes have that huge, fat sound and buttery response.Up until the pre Chus the keywork is a little flimsy though.

When you say ‘portable silver plating kit’ I assume you are speaking of the spot plating wand. As preconditions to using the wand you need to have the affected area thoroughly cleaned & polished. We use Hagerty
All Metal Polish, followed by an acetone swabbing. Second thing is you need to be sure you are getting current flow. The alligator clip needs to be as close as possible to the area to be plated (be careful attaching it to keys cuz the clip will scratch things – sometimes I just hold it snugly against the nearby surface). If you are laying plating you will see a black film forming. That’s what you want to see. It is the new plating that must be polished to show the sheen. The last step, then, is polishing that black stuff to brilliance with either a Hagerty treated polish cloth or more All Metal Polish. Be careful at this stage cuz you can actually
rub the new plating off. To get a thicker plating just repeat the process over the target area. If your surface is clean & there is electrical contact the process is foolproof. If you are not getting the black film then one of the pre conditions isn’t being met. In this case ‘clean’ means a polished surface of bare metal to which the plating can adhere.

Just a note, spot plating is very thin. It will not fill in scratches or pock marks from pitting.You may need to smooth the surface before applying the plating. If you need to talk more about how to do that let me know. Good luck with your project …

Additional Comments
Spot plating kits, also called plating wands, are available for silver, gold, nickel and copper plating applications. Since gold will not adhere directly to brass, either silver or copper must be applied first. The plating wands are fairly inexpensive and will do small spot plating jobs and artistic enhancements quite nicely.You have to adhere to the cleaning process described above though, or the new plating will not have a surface to which it can stick. We actually replaced a gold wash to the bell of a C-Melody that had been damaged using the silver and gold plating wands. It was a time consuming process because you can only do small areas at a time, but the results are well worth it.On that same horn we also added gold highlights to the engraving details much to the delight of the client. Use caution with plating kits because the electrolyte solutions contain poisonous cyanide. Here is a link to Caswell for more information.
Spot Plating Follow-up
Q./b> Can you use the Caswell plating kit on a soprano with the pads still in place? It’s the cups that I will need to re-plate or touch up. Rob …

A.
Affirmative. All that’s needed is to establish the ground connection. We did the bell wash on your True Tone alto with the horn completely assembled. Of course you’ll be doing one key at a time while you have the horn apart for cleaning. Just be careful with the gator clip cuz it will scratch the plating. I have sometimes just held the edge of the ground clip against the horn metal. You have to clean & polish the area you want to plate or the plating won’t stick. On silver the best product to use for that purpose (that I’ve found) is the Silversmith Polish Caswell sells (that’s the stuff with the cyanide, so be careful with it). Hagerty’s All-Metal Polish will work, too. Read up on the main spot plating Q&A (above) b4 you proceed, and pick a small obscure spot to do your first operation.Keep a moist rag handy to wipe up any runs from the plating fluid. It’s quite acid & will mar adjoining areas if allowed to stay there for long.


Additional Comments
Rob is a West Coast pro with whom we frequently collaborate on sax resto work and who supplies us with some of the most striking instruments that we offer for sale in the CS 4Sale pages. We’ll be adding some high level, high quality excerpts from the many consultations we do with Rob. They will tend to be cryptic at times, so read them for the technical content — they’re not our usual mix of information & entertainment … :-)



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