Tissot Powermatic

A
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Deafboy Deafboy
Thanks for the clarification, Al.


I spent a lot of time reading about the design of the Powermatic 80 the last two days. A number of watchmakers and other people who have examined it believe the escape wheel and pallet fork are made from a Delrin-type polymer. Delrin is used for gears in printers because it is durable, quiet, and clean compared with greasy steel gears.

I have six Powermatic watches, one of which went into production the first year the Powermatic was released. All six are accurate within five seconds per 24 hours. If I alternate the night resting position, three of them stay accurate within two or three seconds per WEEK.

I just ordered my first ever watch with a ETA 2824-2 movement, the grandfather of the Powermatic. It will be interesting to see it compares with a modern movement.
 
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ErichPryde
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A AlanTexas
I spent a lot of time reading about the design of the Powermatic 80 the last two days. A number of watchmakers and other people who have examined it believe the escape wheel and pallet fork are made from a Delrin-type polymer. Delrin is used for gears in printers because it is durable, quiet, and clean compared with greasy steel gears.

I have six Powermatic watches, one of which went into production the first year the Powermatic was released. All six are accurate within five seconds per 24 hours. If I alternate the night resting position, three of them stay accurate within two or three seconds per WEEK.

I just ordered my first ever watch with a ETA 2824-2 movement, the grandfather of the Powermatic. It will be interesting to see it compares with a modern movement.

Yes, Delrin is a thermoplastic (a polymer). It's quite durable and in some use cases probably better than steel. Iirc from what has been said in the past, some speedmaster movements use it as a brake/blocking lever instead of a steel part.

Thermoplastics definitely fall under the category of "synthetic materials," but that doesn't mean inherently bad. Some see the term "plastic" as slanderous.

Regarding your accuracy- I'm glad you're happy with your watches and have good accuracy. Older movements are completely capable of high degrees of accuracy within a second per day if they are regulated well; a wearer who knows their own habits and what positions the watch should be rested in can definitely have accuracy you're seeing now. I hope your ETA 2824-2 does as well for you.
Edited:
 
Archer
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ErichPryde ErichPryde
Yes, Delrin is a thermoplastic (a polymer). It's quite durable and in some use cases probably better than steel. Iirc from what has been said in the past, some speedmaster movements use it as a brake/blocking lever instead of a steel part.

Back before I became a watchmaker, in my engineering days, I had a lot of material handling projects, using flexible chain conveyors. The chain looks like this...it can go uphill, down hill, around corners, etc, so it was very effective for the types of product that I was tasked with conveying between different machines tools and testing equipment...

Rexnord chain.jpg


The frame of the conveyor was made of steel, and between the frame and the chain we used a wear strip that could be replaced. The standard material in the industry at the time was UHMW-PE (ultra high molecular weight polyethylene), but that would absorb the cutting and honing oils that were still on the product, and they would swell up, jamming the conveyors.

The solution was Delrin wear strip - I used miles of it on conveyors back then...
 
sheepdoll
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My piano scanner is made from delryin. I have considered using the scraps to see if I could make model watch gears. Or even a part to test fit something like a repeater striking rack. Delryn is amazing stuff. Easy to machine and shape.

Just wait, 437 years in the future, someone will say "I did not know they had delryin in the late 18th century."
 
sheepdoll
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Be careful what you wish for.
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Now the wait begins...
I hope it does come from Finland and not Moscow. Interesting that the price was in UKP. The seller accepted my lowball offer. (probably still to much.) Not sure there is a real demand for these. Still it has been on the bucket list ...

Curious though, when I check the sold listings on eBay, it shows what the seller offered. Not my counter offer that was accepted. It is also interesting I have to click worldwide to see the sold listing.
 
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