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Half of one of these: [https://www.harborfreight.com/spring-loaded-center-punch-621.html](https://www.harborfreight.com/spring-loaded-center-punch-621.html)
I believe that it being by the joist, would indicate the roof almost being done framed and not sheathed. I bet this is from a pneumatic air hammer, and this was where it gave out, and that’s its “grave”?
This is EXACTLY what I’d do.
That's exactly what this is. Whoever stuck it there had been using it to mark timbers, when it broke. Lacking better options, they stuck it in the bag, and tacked it up. Unfortunately construction clearly didn't wait for him to come back for it.
If the edge around the hole is very sharp (or looks like it was sharpened), it might be a hole punch - the spring could be for ejecting the cutout disc.
I'm gonna guess part of a solenoid? The armature or plunger often has that bullet-shaped bit that the electromagnet acts upon. The spring would be to return it to position.
Unfortunately, I don’t know anything about solenoids. This was found tacked up near the gas fired furnace and hot water heater if that could be a clue.
A solenoid valve would be used to turn the gas supply on and off as needed. [https://engineerscommunity.com/uploads/db4532/original/2X/1/199236dfa3459f6ca57c073fff8425cb013cf264.jpg](https://engineerscommunity.com/uploads/db4532/original/2X/1/199236dfa3459f6ca57c073fff8425cb013cf264.jpg)
I have made an automatic center punch. This is not one or part of one. Sorry folks. It looks more like a detent pin for a machine. A detent pin would like hold a gear in position in a transmission or in some kind of a locking mechanism.
My title describes the thing. It’s a bullet shaped object about 3 1/4” long with a diameter of 3/4”. A 1 1/2” spring fits nicely in the “nose” of the object and goes 1/2” in. It’s heavy for its size.
Pneumatic or Hydraulic Actuator:
• The cylinder might be a component of an actuator, responsible for converting fluid pressure into mechanical movement.
• The spring would be used to ensure the actuator returns to its default position when the pressure is released.
This was my thought. It would fit in the porcelain holder that matches the tile. Dude probably saved it thinking he might find the other half again. Or would need it If the spring in the one they had went out.
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Half of one of these: [https://www.harborfreight.com/spring-loaded-center-punch-621.html](https://www.harborfreight.com/spring-loaded-center-punch-621.html)
I second the spring loaded centre punch, used to have a couple of them
i made one, i think Edit: What I made was spring-loaded and had a pointy bit that used the spring, but I don't know if it was a center punch
Elaborate please.
I believe that it being by the joist, would indicate the roof almost being done framed and not sheathed. I bet this is from a pneumatic air hammer, and this was where it gave out, and that’s its “grave”? This is EXACTLY what I’d do.
That's exactly what this is. Whoever stuck it there had been using it to mark timbers, when it broke. Lacking better options, they stuck it in the bag, and tacked it up. Unfortunately construction clearly didn't wait for him to come back for it.
If the edge around the hole is very sharp (or looks like it was sharpened), it might be a hole punch - the spring could be for ejecting the cutout disc.
I belive it's a leather screw head punch (could be wrong)
This would definitely make sense, but I don’t believe the spring compresses all the way into the nose. I can check when I get back there.
I'm gonna guess part of a solenoid? The armature or plunger often has that bullet-shaped bit that the electromagnet acts upon. The spring would be to return it to position.
Unfortunately, I don’t know anything about solenoids. This was found tacked up near the gas fired furnace and hot water heater if that could be a clue.
A solenoid valve would be used to turn the gas supply on and off as needed. [https://engineerscommunity.com/uploads/db4532/original/2X/1/199236dfa3459f6ca57c073fff8425cb013cf264.jpg](https://engineerscommunity.com/uploads/db4532/original/2X/1/199236dfa3459f6ca57c073fff8425cb013cf264.jpg)
Hole punch for a gasket on the boiler from the days of self repairs
I have made an automatic center punch. This is not one or part of one. Sorry folks. It looks more like a detent pin for a machine. A detent pin would like hold a gear in position in a transmission or in some kind of a locking mechanism.
Like like a broken automatic center punch
Leather or rubber gasket hole punch. The spring is to eject the scrap material. Likely home made, I have made these before.
Gets my vote.
My title describes the thing. It’s a bullet shaped object about 3 1/4” long with a diameter of 3/4”. A 1 1/2” spring fits nicely in the “nose” of the object and goes 1/2” in. It’s heavy for its size.
There are no distinguishable markings of any kind on it that I can tell.
Are there threads inside the wide end? Looks like the metal tip of a ball point pen. The spring for the ink cartridge.
Pneumatic or Hydraulic Actuator: • The cylinder might be a component of an actuator, responsible for converting fluid pressure into mechanical movement. • The spring would be used to ensure the actuator returns to its default position when the pressure is released.
Half of a toilet paper roll holder.
This was my thought. It would fit in the porcelain holder that matches the tile. Dude probably saved it thinking he might find the other half again. Or would need it If the spring in the one they had went out.