Large Metal Disc Found in Old Driveway

[bologna321]

Another what is it for you fellow Tnet members since you are so good

Metal disc, heavy, seems to be a silver metal that is coated? Has the numbers 1 thru 0 on one side. The only hole that goes through is the center one.

 

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[mick56]

Metric sun dial?

 

[ANTIQUARIAN]

I'm thinking it's some type of scale weight, but to what I don't have a clue.

Dave

 

[marion moore]

I don't what it is, but it looks like it has 2 counterbalance holes in the front face toward the outside edge. Very interesting. Thanks for posting.

 

[TreasureCatto]

Too me it looks part of an old weight scale dial.

 

[Bigcypresshunter]

I don't what it is, but it looks like it has 2 counterbalance holes in the front face toward the outside edge. Very interesting. Thanks for posting.

Yes it does so that tells us that its something that turns. Could it be a crankshaft harmonic balancer pulley?

 

[bologna321]

Metric sun dial?

Haha

 

[Plug N Play]

Wait ... if we have 24 hrs. in a day, here in the states ... how many hrs. are in a day in England ?

 

[Anduril]

Interesting...
I note that the center shaft is not indexed.
That would mean the numbering is relative, and not absolute (i.e., keyed to a particular shaft rotation).

 

[invent4hir]

The center hole has a circular rust pattern surrounding it indicating that whatever this is, it might have held in place by a bolt and washer.

 

[Bigcypresshunter]

The center hole has a circular rust pattern surrounding it indicating that whatever this is, it might have held in place by a bolt and washer.

Yes and in case I didnt explain it well, those 2 holes that are partially drilled are to remove weight to create a perfect balance during rotation.



Im not sure what the numbers would mean, like was said its not keyed, but I think there would be no reason to balance it so precise unless it revolved at high speeds. I have seen those drill holes before many times. All you have to do is look at any harmonic balancer. And yes it would attach in the center with a bolt.

 

[Back-of-the-boat]

Maybe some type of surveyor marker.

 

[Hawks88]

I agree with harmonic balancer. The pulley for the belt or multiple belts would be mounted to the front and center of that balancing weight. The holes were drilled to perfectly balance it to reduce vibration. ( IMO ).

 

[Reanm8er]

Right on Bch and hawks!

When something is balanced like this, it usually rotates at high RPM. Since it's not indexed the balance only affects the wheel and not the shaft. Another alternative is perhaps a component from a combo lock. The holes are not for balance but to allow the wheel to move the tumblers. The lock would have featured a cover over the front with a small window to read the number. Elgin made some wrist watches like this called "Hour Up" design.

Cool find Bologna!

 

[Plug N Play]

I'm mostly agreeing with the analysis ... but let's examine "indexing" and see if we can continue to discount it, just in case.

Bologna, could you give the back of the wheel a close eye and look for the following?

(Let's imagine a hub and spindle ... pulled tight by a nut on the other side.)

Do the four holes look sharp and deep enough to keep a hub from spinning ?
What's the square looking anomaly ... is there any sort of "tab" associated ?
How about alignment marks ... any tiny groove or nub anywhere around the inner rim ?

They don't LOOK like they are a factor in the picture, but it wouldn't take much to prevent spinning, ... which might apply to the balancing holes on the face.

 

[Anduril]

Maybe the numbers are there so that, after spinning at high speed, you know where to drill the balancing holes?

Is the mark circled in red opposite the number "0" on the front? Or is that just a scratch?

As for the marks on the underside, my opinion is they are marks left as a result of the part's manufacturing process.
(If this were plastic, I would say "injector pin" marks -- but whatever the equivalent is for a cast or forged part, or even a machined part. You have to hold it somehow..)

 

[trdking]

Right on Bch and hawks!

When something is balanced like this, it usually rotates at high RPM. Since it's not indexed the balance only affects the wheel and not the shaft. Another alternative is perhaps a component from a combo lock. The holes are not for balance but to allow the wheel to move the tumblers. The lock would have featured a cover over the front with a small window to read the number. Elgin made some wrist watches like this called "Hour Up" design.

Cool find Bologna!

I am familiar with "Jump Hour" and "Direct Read" but I have never heard of "Hour Up"

I am not inclined to think Harmonic balancer Although not hard to go there. Harmonics would not have the numbers. and this is very small for that. I would lean more to some kind of dial skirt for say a lathe? where you would have to track the increments in each pass and advance. Just my thoughts

 

[trdking]

If any are interested here is an Elgin Direct Read https://www.bonanza.com/listings/19...MI0Ke8p8254gIVHbnACh2GAAdBEAQYBCABEgLVVPD_BwE They use both terms but a true Jump hour should look like this https://www.google.com/search?q=jum...KHaprB90Q9QEwAHoECAcQBA#imgrc=657a0xQczjvqaM: They are loads of fun to collect

 

[Back-of-the-boat]

Was this embedded in the driveway like a marker for a boundary would be placed.That is why I suggested a surveyors marker or did you find other car parts to suggest it is a car part? I am interested in the final solve on this.Other thoughts I had were a metering device for water or gas and the numbers relate to flow of product.Can you scratch the metal to check if brass. If brass I would think gas related.Just throwing out thoughts.

 

[Bigcypresshunter]

I am not inclined to think Harmonic balancer Although not hard to go there. Harmonics would not have the numbers. and this is very small for that. I would lean more to some kind of dial skirt for say a lathe? where you would have to track the increments in each pass and advance. Just my thoughts

I posted that they appeared to be drilled for balancing at hi speed but could a very precise piece of equipment like a lathe dial also need to be in perfect balance? Im not convinced on my harmonic balancer idea either, even though the size is correct as compared to my 4 cylinder. I just threw it out there to explain a theory on the drilled holes. Im leaning toward a large safe, scale or lathe dial. But the partially drilled holes must be there for a reason.