Happy new year!
I have some very exciting news. After looking for a couple of weeks for a router bit of the correct shape to profile the two main boards I finally needed to make one reprofiling a used one. It worked wonderfully and in a matter of minutes I cut and routed the two main boards of the bottom case and I started to lacquer them. The texture and color of the walnut wood is amazing and layer after layer of lacquer it is blending the color with the old wood nicely. It's unbelievable how nice is now considering the pitiful state it had 3 months ago. Many layers of lacquer are still needed to reach the desired finish.
Next challenge was the "connectors" of the reproducer and recording heads. I decided to start with the "swivelling" one because it looked more difficult to make. It was a learning experience to make it and it turned pretty well. I deviated slightly from the original design to be sure that they can't be confused with original ones.
As you can see, I ended fabricating it in 4 pieces: The internal spherical ring with a tapered interior hole, the body with a slight difference in both sides of the internal diameter to accommodate in one end the spherical ring and on the other side the reproducer head and finally an external ring that I made deliberately wider and without the knurling to differentiate it from the original and to hold the little axle that aligns vertically the reproducer.
All the pieces are a press fit and hold together perfectly so for now I have not soldered the external ring nor glued the reproducer till I decide if I nickel plate it later.
I ended doing it of 15 mm of length because as you can see it is what i need to reach the cylinder at the correct distance and angle.
So for the first time I could assemble it and test it and it works almost perfectly!
Why "almost perfectly" you might wonder... Well, it has an annoying problem. From time to time, the carriage binds to the axle and freezes causing the half nut to start jumping on the screw feed and destroying it in a matter of minutes.
After a lot of head scratching and hundreds of measurements I think that I've found the problem. The bronze bushings of the carriage are worn and slightly ovalized and the axle after derusting and polishing is slightly undersized. This becomes a problem when the weight of the horn makes the friction greater and even perfectly oiled it ends binding.
So I've been analyzing how to fix it and finally decided that the bushings were going to be a nightmare to replace but both axles could be replaced with +0,3 mm oversized ones and make a couple of reamers to make the old bushings ad bottom part of the carriage to fit as needed. I've ordered the rods to make both axles. In a couple of weeks they will arrive. Also some new brass (instead of aluminum) half nuts will be needed but that are very easily made.
So next step is to make the rigid connector for the recorder head. I hope to have some time tomorrow to make it.
If you need some of this connectors (or brass half nuts), please contact me. I really don't know what is the best way to sell them because I've seen that the heads all have slightly different dimensions so I'm wondering if a custom fit is the best approach. Regarding the half nuts, I will also need the spring plate that supports the half nut to make the threaded holes to the exact dimensions.
And finally... I'm considering reproducing the famous "Système Verité" because my Coquet was once fitted with one (It came with 4 eye pins under the main board). I would appreciate if somebody can send me pictures of them and dimensions. I suspect that the tube that fits into the carriage is nickeled brass, the rods are made of mild steel and the central wheel of aluminum but I might be wrong. If you are interested in one please also contact me so instead of making one just for me I will make some jigs to make a short production of them. Also, If you need one, send me the dimensions between the eye pins because I've read that there were several sizes.
Regards,
Pedro Martínez