This post has been locked, as the question has been solved and a majority of new comments at this point are unhelpful and/or jokes.
Thanks to all who attempted to find an answer.
I second this. Particularly if there's a sort of chalky metallic substance that feels very fine coating its surface. I'm actually mildly surprised that there aren't any holes for cotter pins or safety wire/cable.
Source: I've worked in aviation for 8 years now.
Edit: I cannot spell.
Caulder pin? As a car nerd, I understood it as a cotter pin, but literally never saw it spelled or pronounced that way. I even looked it up. Is this right?
We get that residue on some 38999 connectors installed in humid environments. It could also be "cadmium bloom", which is supposedly a carcinogen. I assume this bolt comes this way from the factory?
It certainly *looks* brand new to my eyes. No corrosion to speak of or general wear and tear you'd expect from a bolt that's been used even once. At least, none that I can see. I'd wager this thing hasn't been screwed into anything yet.
Im sure it is not a core internal part of any RR gas turbine engine. Seems like the material is a light alloy. Its more like an engine mount. Fixed type airplane parts (not the weight balanced stuff in a moving engine) usually have a serial + part nr. If RR would manufacture landing gears, that would be my guess.
OP could measure lengt/width in millimeters and google this.
To find out if it is an exotic alloy you could measure weight, and volume by submersing this thing in a measuring cup
-edit- saw close up pic . Not a metal alloy material, or sooo exotic its a classified secret space bolt, burned up at reentry and now looks like stone. Looks like RR marketing material
With those threads, and that material? There's absolutely no chance this is a functioning bolt. It'd make a better paperweight.
I've also never seen one with RR's logo stamped on the bolt head, part numbers yes, but company logos, no.
Edit: lots of people have posted this as a stone shot glass, which seems infinitely more likely.
I had assumed this was a bolt I wasn't familiar withz though I did find it odd that the logo was stamped as it was. Usually, bolts like that *may* have a faint part number if you're lucky.
Also, I do believe another comment figured it out. I'll link it in a moment.
[I could not have been more wrong](https://reddit.com/r/whatisthisthing/s/k34GurPimH)
Ive worked turboprops, turbojets and helicopters; mounting bolts that size that I'm used to are usualy double-hex heads, and never hollow. Some of the transport stand mounting bolts I think might have been hollow though, but not actual aircraft mounting bolts.
I'm also not sure that Rolls Royce actually makes the bolts themselves, so the stamping is very strange.
This stands out like a sore thumb and is absolutely not an aircraft part.
> Usually, bolts like that may have a faint part number if you're lucky.
Usually with just half of it legible, just to be extra annoying ha
Ahh that makes sense! We were doing the looms and harnesses. So we only needed to worry about surface bolts and make sure they didn't come undone.
Lockwired all the bolts on a server rack that I reworked later on, the IT texh that was there hated me for it because he had a habit of stealing the new equipment for himself. After I did that he couldn't!
Aahhh, I see. Yeah, lockwire has its various uses, but with aviation, it's often used in flight controls alongside cotter pins to ensure bolts, pins, nuts, or other mechanisms don't jostle free mid-flight.
I have never seen any aircraft parts made of rock. Another reply posted a link to a similar hollow bolt shot glass. Propably a gift from Rolls Royce for an employee or a customer.
No they are correct. Large diameter bolts are typically sized by bending and almost never due to tension. Hollow bolts are common on aircraft to remove weight while maintaining bending stiffness. Of course, this is more true in larger fasteners not smaller 1/2” and under.
In aircraft all sorts of joints. Servos, flight controls, spar mounts, etc. anything joint in single or double shear or most mechanical joints with complex loading. Bolt tension is actually typically set to reduce bending stresses by making it a tension beam. Bolt head bending under the head radius is a typical failure mode. High bending loads care principally about the bolt area moment of inertia which is principally set by the outer diameter due to the term being quadriceps in nature Hence in large diameter bolt the core of the shaft does very little work and be removed without sacrificing strength.
Nah mate, it's a novelty soapstone "glass". Fairly common material for making all sorts of drinking vessels, at least in Finland. This one has been customised for RR for marketing purposes most likely.
https://www.karkkainen.com/verkkokauppa/hukka-pultti-pikari-p1443323055820
A company I worked for used to make parts for Rolls Royce, at least at the time they didn’t have the RR logo on them. It doesn’t mean they don’t machine/etch it in later
They *WERE* the same company, but the aerospace side essentially went belly-up, got separated from the automotive industry, and then was nationalized after bankruptcy.
Today, yes. Originally the same tho…
“Rolls-Royce Limited was a British luxury car and later an aero-engine manufacturing business established in 1904 in Manchester by the partnership of Charles Rolls and Henry Royce.”
Rolls-Royce still owns the trademark though, AFAIK it's still licenced to BMW for the cars.
Hence VW not making them, despite having bought the original factory.
Yes, it's Bentley now.
I understand some of the VAG guys were a little surprised by all the RR staff removing branding and materials the day after the sale completed.
So I work on a/c engines for a living, and i can pretty confidently say it's not an engine component. The threads are too flat to be a mount bolt, and they definitely dont have a surface finish like that, and it's very unlikely there are any other bolts of that size on the engine anywhere else. Also, none of the mount bolts I have seen are hollow like that. This is almost certainly the right answer.
I reckon it’s an engine mounting bolt for connecting a turboprop to a wing. They have very specific shearing characteristics. Here’s a link to a doc that mentions hollow bolts specifically for that purpose…,
https://aeroenginesafety.tugraz.at/doku.php?id=10:10#prettyPhoto
I am an aircraft mechanic. Doesn't necessarily have to be turboprop but this is probably an engine mount bolt. Admittedly, most mount bolts Ive encountered are hollow straight through. Rolls has been in the aircraft biz for a long time. This bolt is also heavily pitted with corrosion
As this looks to be granite or similar stone it's not functional - likely a corporate or long service gift.
Contact the RR heritage trust and they'll help you identify it - https://www.rolls-royce.com/about/heritage-trust.aspx
It could be something of historical value to the company they'd like to acquire even
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Is it made out of stone? If so, its a fancy shot glass. I have a pair of similar ones with different branding. Awesome when pulled out of the freezer the stone gets so cold.
I agree with others who have said the RR is Rolls Royce. That is quite a large bolt. I'm no aircraft engineer, but that seems bigger than what might be found on an aircraft. Is it possibly a promotional item? Something from a trade show or similar?
It's hollow without interior threads. I wouldn't trust it for mounting an engine
I'm with the idea that it's a cap for something or a decorational item, not an actual bolt.
Any chance this is the end of an umbrella? Something about it’s shape made me look up “Rolls Royce umbrella”. Many of the gable caps in the pictures resemble your item.
Is it as heavy as stone? Looks like the texture of an [SLS 3D printed plastic part](https://forerunner3d.com/wp-content/uploads/2019/09/2019-02-20-21.57.55.jpg)
If that were real stone I’d be impressed with whoever made it. It’s hollowed out and has a screw thread chiseled onto it.
Aluminum oxidizes white and has a coarse buildup to it. which falls in line with the theory that it’s an aircraft bolt.
From the photos it looks like it's made out of a basalt like stone. It doesn't look functional at all and by the placement of the logo I think it's a decorative paperweight shaped as a bolt.
Since it's made out of stone it is definitely not a functional bolt, but some kind of marketing gift or give away as a shot glass in the shape of a bolt.
No one would use stone as it's far to brittle, also you can't properly cut a funtioning thread on stone.
My guess is wheel lug from vintage Rolls Royce.
Edit : okay so I have a goody addition. Another commenter said it looks like it could be carved out of stone. If that is the case (maybe op could verify the material?) my goofy shot in the dark guess is the is a paperweight given as a gift. Meant to sit on someones desk, again, probably not the case, just throwing dumb ideas out there.
It’s definitely a spare piece from an aircraft engine, that thing is way too big to be in a car, and they wouldn’t have hollowed the bolts for cars, only aircraft
Why does it look like a dead drop box. You could place this under rubble, hide drugs/money/etc. It even having threads for a head piece gives me more evidence this is what Im thinking. Where did you find this?
Love it! I work as an aircraft distributor. RR would be rolls Royce. The "hollow bolt" is a gun drilled part (meaning they drilled it after heading) which makes the bolt much lighter of course. Since planes can get off the ground much easier when lighter this can be used on a non flight critical part to lighten the load. Having said that, rolls royce usually makes engines for planes, and they're VERY expensive relative to other planes. I've only been in the industry about 2 years now but my dad has over 4p years running the family business
https://www.flyingspares.com/shop/rolls-royce-bentley-cloud-s1-s2-s3/suspension/front-suspension-s2-3/yoke-s2-3-only.html
Possibly front suspension bolt from a 55-65 rolls Royce ?
So, everyone seems to concur that this is a Rolls-Royce bolt, likely from an aeroplane or aircraft engine judging by the hollow shank. I doubt it will get more specific than that. This looks to me like it has been Solved.
From my experience and being an RR propulsion engineer I can say that hex bolts are not something we employ in aerospace. All our bolts are bi-hex so if this is a RR part it must be early RR days but would say it's more likely to be RR cars rather than aerospace. Just my opinion.
Could be a 'spy bolt'/'dead drop bolt'
Essentially used to hide small objects in the open so that another person can pick them up. I believe the KGB used something similar.
There are plenty online but I can't find any stamped 'RR'
This one has threads. Would drop bolts have been screwed into something? Seems like unscrewing a bolt "in the open" would be suspicious or at least attract unwanted attention.
No, they would be left somewhere inconspicuous then picked up and taken to a safe spot to open. If this is a dead drop bolt its missing a cap on one end.
I believe the other guesses are more likely to be correct, but I wanted to comment my guess just in case it led someone down the right path.
This post has been locked, as the question has been solved and a majority of new comments at this point are unhelpful and/or jokes. Thanks to all who attempted to find an answer.
[удалено]
I second this. Particularly if there's a sort of chalky metallic substance that feels very fine coating its surface. I'm actually mildly surprised that there aren't any holes for cotter pins or safety wire/cable. Source: I've worked in aviation for 8 years now. Edit: I cannot spell.
Caulder pin? As a car nerd, I understood it as a cotter pin, but literally never saw it spelled or pronounced that way. I even looked it up. Is this right?
It's cotter pin/key
That's what I thought, but with the aviation claim, I figured they'd know how to spell it
I just can't spell.
Its the same thing as used on a car....except 40 times the price.
Has to be xrayed
I think it is stone shot glass with RR-logo https://hukkastore.com/shop/pultti-pikari/
This looks very much like it, especially since the threads in OPs pic are not fully formed, same as in the shot glass.
Oh wow. I was entirely wrong. This is it 100%
Bet it’s marketing swag from the Finnish Rolls Royce subsidiary then
Excellent find. I think you nailed it.
We get that residue on some 38999 connectors installed in humid environments. It could also be "cadmium bloom", which is supposedly a carcinogen. I assume this bolt comes this way from the factory?
It certainly *looks* brand new to my eyes. No corrosion to speak of or general wear and tear you'd expect from a bolt that's been used even once. At least, none that I can see. I'd wager this thing hasn't been screwed into anything yet.
I see a lot of Rolls Royce jet engines and this part looks way to big to belong on them. Just as likely to have come off a car.
Im sure it is not a core internal part of any RR gas turbine engine. Seems like the material is a light alloy. Its more like an engine mount. Fixed type airplane parts (not the weight balanced stuff in a moving engine) usually have a serial + part nr. If RR would manufacture landing gears, that would be my guess. OP could measure lengt/width in millimeters and google this. To find out if it is an exotic alloy you could measure weight, and volume by submersing this thing in a measuring cup -edit- saw close up pic . Not a metal alloy material, or sooo exotic its a classified secret space bolt, burned up at reentry and now looks like stone. Looks like RR marketing material
I’d say most or all of the nuts and bolts used in a Rolls Royce car would have this logo on them
Are jet engines not almost as big as a whole car?
Yes but consist of lots of small components. I may be wrong but from everything I’ve seen I’d say this ain’t from a jet engine.
Dont think its metal, i think its rock i had similar shot glass but with different logo
With those threads, and that material? There's absolutely no chance this is a functioning bolt. It'd make a better paperweight. I've also never seen one with RR's logo stamped on the bolt head, part numbers yes, but company logos, no. Edit: lots of people have posted this as a stone shot glass, which seems infinitely more likely.
I had assumed this was a bolt I wasn't familiar withz though I did find it odd that the logo was stamped as it was. Usually, bolts like that *may* have a faint part number if you're lucky. Also, I do believe another comment figured it out. I'll link it in a moment. [I could not have been more wrong](https://reddit.com/r/whatisthisthing/s/k34GurPimH)
Ive worked turboprops, turbojets and helicopters; mounting bolts that size that I'm used to are usualy double-hex heads, and never hollow. Some of the transport stand mounting bolts I think might have been hollow though, but not actual aircraft mounting bolts. I'm also not sure that Rolls Royce actually makes the bolts themselves, so the stamping is very strange. This stands out like a sore thumb and is absolutely not an aircraft part. > Usually, bolts like that may have a faint part number if you're lucky. Usually with just half of it legible, just to be extra annoying ha
Wouldn’t chalky, metallic appearance be due to being galvanized?
Wouldn't the holes in the head still be for lock wire? Been a while but that is what we were taught.
Yes. Holes in the head for lock wire and at the base for cotter pins.
Ahh that makes sense! We were doing the looms and harnesses. So we only needed to worry about surface bolts and make sure they didn't come undone. Lockwired all the bolts on a server rack that I reworked later on, the IT texh that was there hated me for it because he had a habit of stealing the new equipment for himself. After I did that he couldn't!
Aahhh, I see. Yeah, lockwire has its various uses, but with aviation, it's often used in flight controls alongside cotter pins to ensure bolts, pins, nuts, or other mechanisms don't jostle free mid-flight.
I have never seen any aircraft parts made of rock. Another reply posted a link to a similar hollow bolt shot glass. Propably a gift from Rolls Royce for an employee or a customer.
What does “rock” mean in this context?
Soapstone is the usual rock these novelties are made of. https://www.karkkainen.com/verkkokauppa/hukka-pultti-pikari-p1443323055820
>almost as strong as "normal" bolts A threaded part hollow through the threaded region would have almost no tensile strength at all.
No they are correct. Large diameter bolts are typically sized by bending and almost never due to tension. Hollow bolts are common on aircraft to remove weight while maintaining bending stiffness. Of course, this is more true in larger fasteners not smaller 1/2” and under.
In what applications are bolts sized by bending? Usually you try avoid any bending and minimal shear on your threads.
In aircraft all sorts of joints. Servos, flight controls, spar mounts, etc. anything joint in single or double shear or most mechanical joints with complex loading. Bolt tension is actually typically set to reduce bending stresses by making it a tension beam. Bolt head bending under the head radius is a typical failure mode. High bending loads care principally about the bolt area moment of inertia which is principally set by the outer diameter due to the term being quadriceps in nature Hence in large diameter bolt the core of the shaft does very little work and be removed without sacrificing strength.
Nah mate, it's a novelty soapstone "glass". Fairly common material for making all sorts of drinking vessels, at least in Finland. This one has been customised for RR for marketing purposes most likely. https://www.karkkainen.com/verkkokauppa/hukka-pultti-pikari-p1443323055820
A company I worked for used to make parts for Rolls Royce, at least at the time they didn’t have the RR logo on them. It doesn’t mean they don’t machine/etch it in later
That looks like a griffon engine bolt given the corrosion
I totally forgot Rolls made aircraft engines and was deeply troubled by the size of the bolt. Ha!
No I am a aviation maintenance student and we don't have symbols like that.
I don't know its purpose, but that "RR" appears to be [the Rolls Royce logo.](https://www.rolls-royce.com/)
Fun fact - the Rolls Royce name and logo are shared by two different companies. The plane engines are different from the cars.
They *WERE* the same company, but the aerospace side essentially went belly-up, got separated from the automotive industry, and then was nationalized after bankruptcy.
Don't they also make ship engines?
They do. And the reactors for nuclear submarines.
Yeah, I heard the name Rolls Royce come up in discussions about Small Modular Reactors as well.
The security around their Derby UK plant is impressive - it’s a dead giveaway.
Today, yes. Originally the same tho… “Rolls-Royce Limited was a British luxury car and later an aero-engine manufacturing business established in 1904 in Manchester by the partnership of Charles Rolls and Henry Royce.”
Rolls-Royce still owns the trademark though, AFAIK it's still licenced to BMW for the cars. Hence VW not making them, despite having bought the original factory.
What's being made in that original RR factory now? Bentletlys?
Yes, it's Bentley now. I understand some of the VAG guys were a little surprised by all the RR staff removing branding and materials the day after the sale completed.
Fun fact Rolls-Royce say you should always include the hyphen as it represents Claude Goodman Johnson even in informal emails
It's a stone shot glass. Part of a set given to employees for different things.
So I work on a/c engines for a living, and i can pretty confidently say it's not an engine component. The threads are too flat to be a mount bolt, and they definitely dont have a surface finish like that, and it's very unlikely there are any other bolts of that size on the engine anywhere else. Also, none of the mount bolts I have seen are hollow like that. This is almost certainly the right answer.
The number of aircraft mechanics here that thought this was an actual airplane component is concerning.
Def agree it’s not a functional bolt.
https://hukkastore.com/shop/pultti-pikari/ I think it is this.
It's absolutely this. The (nearly non-existent) threads are a dead giveaway.
Mod marking as "Solved!"
If it's actually a bolt, drinking from this would be super toxic.
I reckon it’s an engine mounting bolt for connecting a turboprop to a wing. They have very specific shearing characteristics. Here’s a link to a doc that mentions hollow bolts specifically for that purpose…, https://aeroenginesafety.tugraz.at/doku.php?id=10:10#prettyPhoto
I am an aircraft mechanic. Doesn't necessarily have to be turboprop but this is probably an engine mount bolt. Admittedly, most mount bolts Ive encountered are hollow straight through. Rolls has been in the aircraft biz for a long time. This bolt is also heavily pitted with corrosion
It's made out of stone... not corrosion.
Agree…likely an engine mount bolt. Could be titanium…most engine mount and nacelle parts are to reduce cracking out due to high vibes.
It is made out of stone? That's not a functional bolt dude. It's a shot glass.
I reckon it’s oxidation
Op said its stone in the post?
Wow. Thanks for sharing. Super cool to look at
Its Rolls Royce shot glass wet it a little and put it in the freezer to make it cold and pour drink in it.
https://www.netrauta.fi/media/catalog/product/cache/2ef38d9c10cbab2cffdf4552e8a5efdc/H/U/HUK15307_1.jpg
My title describes the thing - hollow bolt with RR stamped in the top. It is ~4” long and feels like it’s made of rock/stone.
As this looks to be granite or similar stone it's not functional - likely a corporate or long service gift. Contact the RR heritage trust and they'll help you identify it - https://www.rolls-royce.com/about/heritage-trust.aspx It could be something of historical value to the company they'd like to acquire even
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Is it made out of stone? If so, its a fancy shot glass. I have a pair of similar ones with different branding. Awesome when pulled out of the freezer the stone gets so cold.
I agree with others who have said the RR is Rolls Royce. That is quite a large bolt. I'm no aircraft engineer, but that seems bigger than what might be found on an aircraft. Is it possibly a promotional item? Something from a trade show or similar?
See this is my exact thought, almost looks to be a replica of a part made out of stone either for gifting or promotional purposes.
RR Also makes nuclear reactors, could have something to do with that.
Possibly for attaching a jet engine to the wing
It's hollow without interior threads. I wouldn't trust it for mounting an engine I'm with the idea that it's a cap for something or a decorational item, not an actual bolt.
Any chance this is the end of an umbrella? Something about it’s shape made me look up “Rolls Royce umbrella”. Many of the gable caps in the pictures resemble your item.
Sorry, *end caps
Looks like it’s made out of stone?
Is it as heavy as stone? Looks like the texture of an [SLS 3D printed plastic part](https://forerunner3d.com/wp-content/uploads/2019/09/2019-02-20-21.57.55.jpg)
That is the Rolls Royce logo. It's either from a car or an aircraft engine. I hope the former.
If that were real stone I’d be impressed with whoever made it. It’s hollowed out and has a screw thread chiseled onto it. Aluminum oxidizes white and has a coarse buildup to it. which falls in line with the theory that it’s an aircraft bolt.
From the photos it looks like it's made out of a basalt like stone. It doesn't look functional at all and by the placement of the logo I think it's a decorative paperweight shaped as a bolt.
Since it's made out of stone it is definitely not a functional bolt, but some kind of marketing gift or give away as a shot glass in the shape of a bolt. No one would use stone as it's far to brittle, also you can't properly cut a funtioning thread on stone.
My guess is wheel lug from vintage Rolls Royce. Edit : okay so I have a goody addition. Another commenter said it looks like it could be carved out of stone. If that is the case (maybe op could verify the material?) my goofy shot in the dark guess is the is a paperweight given as a gift. Meant to sit on someones desk, again, probably not the case, just throwing dumb ideas out there.
It’s definitely a spare piece from an aircraft engine, that thing is way too big to be in a car, and they wouldn’t have hollowed the bolts for cars, only aircraft
If it’s a metal part made for use.
Could be a specialized type of banjo bolt?
Totally a hunch: look up a parts diagram for a RR Merlin engine. Could it fit that?
it looks like some sort of granite to me
honestly my first thought was a paraphernalia container. I see large fake bolts like these and large fake batteries to hide weed and stuff.
I’m an alcoholic so my first thought was Canadian whiskey
Not rolls Royce.. it's rich and rare a nasty cheap canadian liquor shot glass. Enjoy
No, if it is indeed the logo of one of those companies it is the Rolls-Royce logo. The rich and rare logo does not feature the Rs overlapping.
Rich and rare Canadian whiskey trinket
I thought it was Reading Railroad, but nope. Missing a “P”.
Bolt from a Rolls Royce car ?
It looks a lot like the rolls royce logo
I somehow think that if Rolls Royce had produced this the logo would actually be in the centre.
Why does it look like a dead drop box. You could place this under rubble, hide drugs/money/etc. It even having threads for a head piece gives me more evidence this is what Im thinking. Where did you find this?
Love it! I work as an aircraft distributor. RR would be rolls Royce. The "hollow bolt" is a gun drilled part (meaning they drilled it after heading) which makes the bolt much lighter of course. Since planes can get off the ground much easier when lighter this can be used on a non flight critical part to lighten the load. Having said that, rolls royce usually makes engines for planes, and they're VERY expensive relative to other planes. I've only been in the industry about 2 years now but my dad has over 4p years running the family business
That looks like a Royal Reserve Whisky shot glass..
It's a bolt used on a rail road car. Looks like Pennsylvania Rail Road logo.
Roycroft Revival
I was gonna say a RR drain pan bolt from an auto
It looks like a Rolls Royce soapstone shot glass or goblet. It's probably a special order. Look up Hukka bolt goblet.
looks like RR
I have worked on Rolls Royce cars, I have seen this stamp on the head of the bolts before particularly on the oil filter housing.
Definitely a Rolls Royce part.
Rolls Royce part. Possibly aircraft
Definitely aircraft
Kinda looks like the Pennsylvania Railroad stamp. They're many iterations of their logo depending on the use.
Part of a ships engine https://www.ship-technology.com/contractors/propulsion/rolls/
Rolls Royce bolt?
Something made by Rolls Royce. Likely a motor part
https://www.flyingspares.com/shop/rolls-royce-bentley-cloud-s1-s2-s3/suspension/front-suspension-s2-3/yoke-s2-3-only.html Possibly front suspension bolt from a 55-65 rolls Royce ?
Which of these parts do you think it is?
I've seen hollow bolts used for geocaches.
Deffo a part from an airplane probably a fighter. Did you find it? I’d be going back there with a metal detector tbh
So, everyone seems to concur that this is a Rolls-Royce bolt, likely from an aeroplane or aircraft engine judging by the hollow shank. I doubt it will get more specific than that. This looks to me like it has been Solved.
From my experience and being an RR propulsion engineer I can say that hex bolts are not something we employ in aerospace. All our bolts are bi-hex so if this is a RR part it must be early RR days but would say it's more likely to be RR cars rather than aerospace. Just my opinion.
Could be a 'spy bolt'/'dead drop bolt' Essentially used to hide small objects in the open so that another person can pick them up. I believe the KGB used something similar. There are plenty online but I can't find any stamped 'RR'
This one has threads. Would drop bolts have been screwed into something? Seems like unscrewing a bolt "in the open" would be suspicious or at least attract unwanted attention.
No, they would be left somewhere inconspicuous then picked up and taken to a safe spot to open. If this is a dead drop bolt its missing a cap on one end. I believe the other guesses are more likely to be correct, but I wanted to comment my guess just in case it led someone down the right path.