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Pathé Coquet in need of lots of love
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Author:  JerryVan [ Tue Oct 24, 2017 1:49 pm ]
Post subject:  Re: Pathé Coquet in need of lots of love

walser wrote:
Hi again,

Before telling you about my progress let me show you a couple of important pictures about the leadscrew and half nut.

As you can see, the thread is not symmetrical. One side is vertical and the other slanted. The vertical side is the "pushing side" so it is very important to put the half nut in its correct orientation.

That's a buttress thread. Nice job reproducing it!

Author:  walser [ Wed Nov 08, 2017 6:35 am ]
Post subject:  Re: Pathé Coquet in need of lots of love

Sorry for the lack of updates recently. Tons of work and travelling do not help on the restoration of this Coquet.

After a long treatment to get rid of the woodworms and finding the walnut wood finally I felt brave enough to attack the restoration of the case.

The case was wrapped in film after being soaked in woodworm treatment and left in a freezer for several weeks. This is rather overkill but the last thing I want at home is a problem with woodworms.
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The first thing I did was to try to remove the tiny screws that held the border of the lid. They were very rusty but I managed to save all of them.
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Then the real battle began. Using very thing spatulas and cutters I started removing the most damaged parts and they literally disintegrated. They were held by the varnish most of them.
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And finally all the damaged wood is removed!
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This are the pieces that I will use for replacing the damaged ones. You can also see the shellac and hide glue that I will use.
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I have much more walnut wood so if somebody is looking for replacement piece feel free to send me a PM.

Stay tuned!

Author:  walser [ Mon Nov 13, 2017 5:36 pm ]
Post subject:  Re: Pathé Coquet in need of lots of love

Some more progress this weekend.

I finish the tube that connects the horn to the reproducer. Its made of mild steel and the diameter must be 15,7 mm in order to fit the carriage and horn. The screws are 1,6 mm with the tip of the thread turned down a smidgen to fit as the axle the holes of the piece that holds the reproducer.
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The horn I've managed to find had the mouth badly distorted. With a clamp made out of wood and lots of patience I manage to straighten and shrink it till its a smooth but tight fit on the tube.
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I also started on restoring the reproducer and recorder heads. Both had the glass diaphragm broken and I've not found replacements. (If somebody knows a source for them please write me!). From previous restorations, I've seen that if you use a 0,2 mm thick mica diaphragm, the sound is very similar to the 0,3 mm thick glass. I needed to carefully delaminate some mica and glued with shellac the sapphire and cutter. Now they are ready to receive their gaskets and beeswax.
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Author:  Curt A [ Mon Nov 13, 2017 7:45 pm ]
Post subject:  Re: Pathé Coquet in need of lots of love

Thanks for the update... I love to see the results of bringing back something that appeared to be beyond repair.

Author:  Marco Gilardetti [ Tue Nov 14, 2017 9:53 am ]
Post subject:  Re: Pathé Coquet in need of lots of love

Same here, amazing job!

Author:  walser [ Mon Nov 27, 2017 4:54 pm ]
Post subject:  Re: Pathé Coquet in need of lots of love

Time for a new update!

With a short week end in sight I decided to attack the challenge of making a replacement of the famous mandrel spur gear.

I desoldered it from the mandrel pulley and measured it, found the suitable material and even made the cutter with the correct profile of the teeth.
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I cut the 43 teeth... Its a tedious job that requires all your attention during hours because one single step done wrong and you destroy the gear.

And it was a disaster.

Not because of the gear that I made but because of the other two gears (the big ones) that I thought that I saved them gently filing the damaged teeth. When I tried them, they were unacceptable NOISY! I would never be happy with such a noisy phonograph. So, with my level of frustration at its peak I decided to search for another solution. As I said before, this gears have no equivalent to nowadays standards but I've found that the metric module 0,3 is quite close. I've found for peanuts some 100 and 50 teeth gears that are almost the same diameter. I will have to make a bushing for one of them and turn the shaft to the correct diameter on the other two and I think the difference between the 43 vs 50 and 86 vs 100 teeth will not be very visible.

I have no pictures of the gear I made because I totally forgot to take them in the middle of my frustration.

So to build some motivation again I decided to totally change of matter and spend some time rebuilding the lid. I made a Small jig and attached it to the router and 20 minutes later I had some very nice walnut profiled strips to the exact shape as the old ones.
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I also made a quick jig to straighten the deformed part of the top of the lid. It required several cycles of moisturizing and gentle heat under pressure till it regained its original shape.
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Next weekend I will start testing how to color match the new wood. I can tint the wood or tint the lacker. I already have prepared some shellac dissolved in alcohol to do the tests.

Stay tuned!

Author:  Marco Gilardetti [ Tue Nov 28, 2017 4:02 am ]
Post subject:  Re: Pathé Coquet in need of lots of love

Radial gears tend to be noisy anyway, that's why helical gears were introduced. I'm curious to read if your Coquet will do better with the generic gear replacement.

Once again, I admire your commitment with a phonograph which was in such poor conditions.

Author:  walser [ Tue Nov 28, 2017 10:47 am ]
Post subject:  Re: Pathé Coquet in need of lots of love

Hi Marco,

Yes, radial gears are noisy. I have another Pathé phonograph and its noisy but bearable. Believe me, this one was like a concert of magpies!


Pedro Martínez

Author:  walser [ Tue Dec 05, 2017 4:51 am ]
Post subject:  Re: Pathé Coquet in need of lots of love

It runs!

I managed to find some gear blanks. They were too thin so I decided to use two in parallel on each gear.

So out came the lathe and I cleaned the stripped gear of the mandrel.
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Then the two first blanks were cut to size. The leather strip you can see in the picture is to protect the teeth.
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And voila! the first gear is ready to be soldered.
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Then I cut the gears for the leadscrew. They are a press fit in the shaft so it needed endles microscopic cuts and trials till they fitted as I wanted.
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Last but not least was the middle gear. This one required several attempts till I was satisfied wit the result. The first thing I noticed was the shaft-bolt was not round. The bearing surface was ovalized and tapered because of the wear so the first bushing I made was sloppy. I rectified it and made a second bushing but this time I ended a smidgeon too thin so the gears were not a tight fit and I as sure that they will move when I soldered them. So a third bushing was made and this time it was absolutely perfect.
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And the reassembly began. I soldered the gears and assembled them. It fits like a glove! I needed to ovalize a millimeter the hole of the shaft of middle gear to compensate the slightly smaller diameter of the gears but that's all.
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And with much trepidation I tested it... it runs smooth and absolutely silent! I'm really very happy about it.
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Next challenge: the connectors of the reproducers.

Stay tuned!

Author:  Curt A [ Tue Dec 05, 2017 9:20 am ]
Post subject:  Re: Pathé Coquet in need of lots of love

Glad to see it working again... you apparently have a lot of patience... ;)

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