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.

 

[Reanm8er]

Here's another observation. Se the radial groove that runs through the notches on the numbered side. That a guide for whatever kind of pins dropped into the notches. Radial indexing!

 

[Bigcypresshunter]

Here's another observation. Se the radial groove that runs through the notches on the numbered side. That a guide for whatever kind of pins dropped into the notches. Radial indexing!

somebody busted open a large safe?

 

[Reanm8er]

Could be?

 

[cudamark]

I agree that it's something meant to be spun at high enough speeds to warrant the need to be balanced. Not a harmonic balancer however. For harmonics to be reduced or eliminated, it would have to be a two piece unit with rubber in between the two pieces to have a dampening effect. Now it's possible that this is just the center section and the rubber insulator and outer ring are missing. The lack of a keyway or other means of indexing the center from turning on a shaft is a bit troubling though. Usually when you spin something on a shaft, you want them to spin together at the same rate with no slippage. Otherwise there might be wear on their mating surfaces or a misalignment of the numbering marks. This is assuming they were meant to spin together and there was some resistance between the two.....ie..... the shaft and hub are connected to something else and drive (or are driven) by some other component in the mechanism. The lack of attaching points on this part indicates to me that it's at the end of a shaft and doesn't drive anything else. The numbering system suggests the need for a specific location to be identified.

 

[trdking]

I agree that it's something meant to be spun at high enough speeds to warrant the need to be balanced. Not a harmonic balancer however. For harmonics to be reduced or eliminated, it would have to be a two piece unit with rubber in between the two pieces to have a dampening effect. Now it's possible that this is just the center section and the rubber insulator and outer ring are missing. The lack of a keyway or other means of indexing the center from turning on a shaft is a bit troubling though. Usually when you spin something on a shaft, you want them to spin together at the same rate with no slippage. Otherwise there might be wear on their mating surfaces or a misalignment of the numbering marks. This is assuming they were meant to spin together and there was some resistance between the two.....ie..... the shaft and hub are connected to something else and drive (or are driven) by some other component in the mechanism. The lack of attaching points on this part indicates to me that it's at the end of a shaft and doesn't drive anything else. The numbering system suggests the need for a specific location to be identified.

Providing the drill holes were intended for the purpose and not added after the fact By a kid?

 

[Reanm8er]

IMO the radial indexing suggests that the clearance between the wheels and what they ran in might become inconsistent. This would cause the detents not to drop into their notches as designed. So, you control that relationship with radial guides that will absolutely guarantee a failsafe connection and precise indexing.

 

[Reanm8er]

With all due respect trdking, when you were growing up did you ever know a kid with a lathe and milling machine?

 

[boogeyman]

Truthfully? Yeah, me! Ten years old grandpa gave me a table top drill press, two key machines, a grinder, and a lathe. Only thing was the lathe had to stay in his shop until I was big enough to lift the tail stock end and put it on the pickup. Years later, I realized the psychology behind this. He could keep an eye on me and teach me, and most of all determine if I had developed common sense & shop safety. Another of the neighborhood boys had a real nice woodworking set up but spent most of his spare time molding lead soldiers & other toys. So, that's not so far fetched.............

Now that I think about it, maybe I should've gotten into toy soldiers! That kid always had money from selling & in later years he dusted off his stuff and made pitchers plates & silverware for the folks into miniatures. Guess I missed that boat!

 

[Terry Soloman]

It is the base of an old garden Sundial.

 

[Bigcypresshunter]

It is the base of an old garden Sundial.

A 10 hour sundial? Keep in mind the numerals are evenly spaced from 0 to 9.

 

[bologna321]

Here's an updated pic, under some dirt in the backside I did find the number "1" so I think this might be the index point some were asking about. It's not brass, i was able to scratch it with steel and its a sliver metal underneath, but it's not lead. IDK what it is made of.

 

[Bigcypresshunter]

It's not brass, i was able to scratch it with steel and its a sliver metal underneath, but it's not lead. IDK what it is made of.

did you test with a magnet?

 

[Gambrinus]

My thought about the part is that it is die cast because of the four indents on the backside, which are ejection pin marks. The metal is probably a zinc alloy like Zamak.

I think the indents on the front were for a ball detent. (https://www.google.com/search?client=firefox-b-1-d&q=ball+detent)
And the indented circle on the face is the track were the ball would would ride when the part was being turned probably by hand.

Just my thoughts on it.

 

[Bigcypresshunter]

I didnt realize it was non ferrous. Nobody ever said or I missed it. I see the ejection pin marks so we can assume its die cast zinc alloy of some kind. That would rule out harmonic balancer..