A Sampling of Xaphoon Mold Correspondence…

Hello Brian, Gary

I compared bore diameters today between prototype # 9 and most recent production samples. The bore on prototype # 9 is .007" larger than the production samples. Increasing the bore on the production mold will require approx. two weeks. I would like first to try increasing the bore with processing temperatures. We can try this next week when the mold gets reassembled from plating the tone hole pins, provided the plating is successful. The letters of the address are raised only .003" to .007'' due to the limited space we have for character height, width and thickness. If we try to raise them more, they will wash into each other from the 40 degree conical shaped cutter we will be using to cut each character into the mold. -Jeff

Aloha Jeff and Gary!

I'm really looking forward to next week's tests with following the reassembly of the mold with the plated tone hole plug. Working with the mold temperature to increase the bore size sounds like a wonderful solution if it works. I'm also hoping that mold temp. adjustments will flaten the lay table as well. In comparing the bore size between #9 prototype and molded samples, did you also compare the rate of the curvature in the bell section? The 2 week physical correction of the bore diameter you mentioned... Will that be plating as well or re-machining? This question mainly has relevance if the bell curvature section of the inside diameter needs correction as well. Let's hope for the best. Did you get a chance to drop by an instrument to each of the container company in Elkhart? Tri-Lakes is the company that actually asked for it and seemed eager for the chance to design custom packaging for the final product. Thank you for the good work, -Brian

We were unable to increase the bore diameter today with processing temperatures. The tone holes are larger in diameter now after plating, like prototype # 9. Do you want to try the instrument with the larger tone holes and undersized bore, or should we plate the core also to increase the bore diameter? The downside to plating the core now is that if things do not go perfect, there is insufficient time to correct while you are here. Please advise. Jeff

Dear Jeff,

It's good to hear from you. I assume you have been working miracles as usual. If you really think we have a good chance of plating the core successfully in the next few days, I would say let's go with it. I really feel that if we can restore the intended dimensions of prototype # 9 we will have something that will make all of us perfectionists happy. We have a small set back with AM Plating. Their 6 week delivery time stated when I made the order would have met our deadline, but I think I neglected to actually inform them that our deadline was critical. However I Fedexed yesterday 400 ligatures which I had on hand. They are due to arrive no later than 5 pm Friday.

Question: I am guessing that the shrinkage will be slightly more pronounced in the flat table of the mouthpiece, it seems to me the rigity of the full thickness of the surrounding circumference would slightly hold up the edges of the table allowing the center to shrink downward microscopically. Am I imagining this potential effect? -Brian

The opposite could happen. I cannot predict this.   -Jeff

Regarding shrinkage: Greater shrinkage would shorten the overall length, reduce the external circumference, reduce hole diameters, and reduce the internal circumference, all by a proportionate factor, eg. 1%.If you can estimate how much shorter the instrument should be, how much larger the bore should be, and how much larger the hole diameters should be, I ca provide an assessment on whether it can be accomplished with an alternate composition. We cannot make the tone holes larger with composition or process, but we can make them larger by plating the steel pins forming the holes with electroless nickel.

The samples we sent you were from one specific setup. Next time we sample, we will measure the variation in table flatness and advise whether we can improve on the variation.

 [Ed. Note: See what I mean? :-) ]

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