Most of the farm houses, barns, sheds and root cellars on my family's various farms had those mounted inside. That was back in the 1970's, and I remember resetting one after one of my little cousins knocked the trigger out and set it off. It took almost 5 minutes to fully rewind the spring. There are 3 different sizes that I am aware of. We used the large ones (about 12" across) in the outbuildings and barns since they were MUCH louder. The small one like you have in the video was usually used in the house. The medium size one we used in the equipment shed and the root cellar. The ones I am familiar with have a center cap on the front which is the "trigger" and it is wound from the back. You cannot put the trigger in place until the spring is fully wound. Once it is wound, the trigger button will slide into place. We could get replacement trigger buttons at the Western Auto in town, or at the fire department.
That style were in the house where I grew up, built in the 1970s. I believe we had Vanguard Thermosonic ones, a brown color bell and an odd chrome finned bit around the fusible pin.
You laugh, but I still use that phone. I like having a landline and all the phones connected to it were made in the 80s or earlier and have mechanical ringers. The oldest one is from the 60s (I will not give up touch tone). I really, really do not like electronic ring-tones.
In the 1960's a guy came to our door selling this type of alarm. After looking over the house he suggested that we needed at least 4 of the alarms. About $300 worth. Seeing that I was showing some interest , up went the pressure. He could smell a sale. He proceeded to tell about lady just a few blocks away that had recently purchased an alarm. Why just a few days after she purchased her alarm', she had a fire and it saved her life . I just let him go. This was followed by several more stories along the same line. After listening to his sales pitch for 20 or 30 minutes, I had lots of time and very little money in those days. I asked, Oh do you get a free fire with every alarm system? He jumped up SLAMED his sales book shut and exclaimed this is not a joking matter. .Madder than hell, he couldn't get out the door fast enough. I loved door to door salesman.
When I was in college I used to string along telemarketers. Get them talking while I folded laundry or something, thinking they had me on the hook to buy a magazine subscription or whatever, and then after 20 minutes tell them, "Well, it's been nice talking, gotta go now, bye!" and hang up. It was kind of fun, but I guess it was also a little mean.
I'm with you, I'm fascinated by just how much we were able to do with purely mechanical analog machines. Things like the Norden bombsight, the computers battleships used to aim their guns, down to fairly simple things like this, time clocks, juke boxes, and vending machines. I grew up around such things and while I'm not giving up my modern electronics, these things should be preserved.
My father owned a woodworking factory and sawmills near London, England. I remember that there were lots of those hung around the workshops near the machinery. The sawdust in the atmosphere ( this was in the 1950’s) and around the shop was a big fire hazard.
Fascinating! In general I like devices that dont need batteries - as this one clearly explains, still functioning after 60 or 70 years. However, the modern smoke alarms are much more capable. They dont need to get warm at all for sounding the alarm, since they detect smoke not heat. And to quickly heat up that little rod above 50°C, the air needs to be significantly warmer. Meaning, the fire may be in a stage where the danger zone for smake inhalation is long passed. Crucial because most people die from the smoke, not from burns. But for the time the Wilkinson device was sure better than nothing. And by the looks also relativly inexpensive, which is also a factor if you want that many people use it.
@@tarstarkusznah not louder then the hardwire ones of like apartment building. They test mine every year and it's so loud it legit hurts your ears bad when in the same room as the alarm.
We've been replacing some of the ion/photoelectric smoke alarms with modern heat triggered ones in places like the kitchen and some bedrooms. The amount of false triggering especially with photoelectric ones, has caused us to start to ignore the alarms(When they go off at 2am they become excessively annoying) and brand new ones develop problems after a year or two.. Ones you trust are better than ones you ignore.
For many years, in my Mom’s house, in the furnace room, we had an electrical version of this. Rectangular and a little larger than a cigarette pack, it had an exposed bimetallic strip on the bottom. When heated, it would close a contact, connecting a single D-Cell to an electric bicycle horn that would sound continuously until the battery died, the room cooled or the whole unit was burned up. Testing it consisted of poking the bimetallic strip with your finger. If it let out a lame croak, it was time for a new battery.
Wow. I found one of these in my attic. My dad was a firefighter so I thought it had something to do with that. I wound it up and yeah it started ringing. It still had some spring tension left and everytime I walked by it the vibrations from my footsteps would allow it to unwind a bit more and it would ding to each one of my footsteps
My previous house was built in 1949, and had a similar clockwork fire alarm on the kitchen ceiling. It was one of the types that had a center button trigger, but when I looked at it, it also used a fusible link to set it.
When my brother & I were kids, we had mechanical fire alarms in our bedroom and one in the living room. Rather than a low heat metal pin they used a plastic cap that would melt, given high enough temperature. You could also very simply pull the cap off to test and to occasionally release the spring tension. It was very loud as I remember.
Given that the percentages of each element are known, you could try testing the density of the metal in a measuring cylinder, then finding which one matches most closely. If you don't have a measuring cylinder, but do have a long, thin tube, you can use distilled (or just soft) water and a set of scales. Mark the water level before dropping it in, the water level after and then weigh the amount of water needed to get to the upper water level by placing the cylinder on a set of scales, zeroing them and adding water to the upper mark. I've used the latter method to find out, roughly, what certain unknown metals are from metal detecting.
I am fascinated by cardboard boxes and commercial folding cartons. I worked at the home Depot and it's literally the bread-and-butter of the dang place I really understood how many different cardboard manufacturers how much standardization there is in the industry and how awesome it is that we ship things in paper.
Please do a video on the history of folding boxes used to hold retail products. Watching this video, I somehow realized that I would be utterly fascinated by such a topic. 😮🤭😉
I would think that the metal pin will have slightly higher melting temperature than the actual actuation temperature. Pin will start to go soft and fail before it is actually fully molten due spring pressure pulling it apart. I can see the fire bell going off accidentally during very hot summer days, especially in kitchen when cooking, not unlike modern smoke detectors. Neat little device!
Of course, you're brilliant! Obviously they never actually tested the device! And no one prior to your birth knew anything about material properties! How blessed we are to be allowed to walk in your shadow! Give people some credit that they actually knew what they were doing
I would guess the alloy of the fusible pin is Field's Metal which melts at 62ºC but with some gallium added to the lead/tin/indium alloy to lower the melting point. A similar metal was used by Leica in their 1930's black enamelled camera bodies, to fill the very fine engraving, as being more robust than paint.
When I was a kid in the 60s, a salesman came to our house and made a pitch for a similar fire alarm, but the low temp alloy was in the center of the round alarm.
Ooh! I have a similar one! It has an art decco trigger in the center of the bell, presumably for a fusible link, that holds a quarter quite nicely. It was responsible for much hilarity and mayhem in its second life.
This reminds me of a friends front door bell - that's completely mechanical as well - You wind it up and when a visitor presses the button, it rings until they let go again so a very common mechanism over here in the UK.
I remember a very similar alarm at my grandparents house... just with a bigger silver bell.. . they also had the fire bomb glass ampules filled with carbon tetrocloride... I still have one of those.
There's a family of alloys called "Cerrolow" that is available in various eutectic and non-eutectic variants, and various melting points. I would assume it is something between Cerrolow 117 and Cerrolow 136. Both seem to be used as fusible elements, although their main usage seems to be for machining fixtures.
Interesting fire alarm. I installed several thermal sensors around the house and shed to augment the smoke alarms and wired them up to a loud bell). They all have 190F (87.8C) trip points. 125F (52C) seems pretty low here in the lower 48 but I guess it was find in England.
Are you gonna hit it with a heat gun and a thermal camera and see what it does? I think that would make an interesting video. Might also be some chemistry RUclipsrs who could collaborate on figuring out what the pin material is.
It could be that it simply weakens enough at 125F that it lets go before it fails. Kind of like steel weakens dramatically long before it reaches melting point.
2:47 It looks like you've used a º (U+00BA, Masculine Ordinal Indicator) instead of a ° (U+00B0, Degree Sign). Some fonts render the former with that underline-looking bit, or even a double underline.
I think the proper terminology for the pin slowly failing is that the metal have undergone creep, it is an issue with a lot of materials that are under constant pressure.
I remember these as pretty common when I was a kid. I also remember breaking one of them playing with it by forcing it to overwind the spring. Crap , I am sorry about that but dont remember who owned.
A fully mechanical, no batteries required fire alarm, fascinating. The only possible improvement I can see to make is to replace the fusible link with a modern one such as used to hold sprinkler heads shut. Other than that, it's pretty much perfect.
Not for use in Furnace Creek California. You need to get a handheld XRF analyzer. It would be a perfect fit for your channel to identify the strange materials you often feature.
@ChrisAthanas why would it just snap off? This one's been intact for over half a century. most smoke and fire alarms are false alarms and the detection device should be expected to be able to be reused, but wouldn't be able to be reused in the case of this device.
a new question then ... if you scratch that thermal rod with your finger nail or a metal nail ... does it break out ? , & into a regular rod material ? or some sort of rust ?
Having the replacement for the melt-y part of apperatus WITH the apperatus, where it is exposed to the same kind of temperatures as the original it's replacing, strikes me as odd. Most likely the replacement pin isn't for when the alarm actually alarmed in anger, but as a replacement due to accidental breakage of the original. Methinks the alarm itself will most likely be a piece of slag after having alarmed and having saving the house occupants from the fire, anyways. Fire alarms are tragic creatures.
Most of the farm houses, barns, sheds and root cellars on my family's various farms had those mounted inside. That was back in the 1970's, and I remember resetting one after one of my little cousins knocked the trigger out and set it off. It took almost 5 minutes to fully rewind the spring. There are 3 different sizes that I am aware of. We used the large ones (about 12" across) in the outbuildings and barns since they were MUCH louder. The small one like you have in the video was usually used in the house. The medium size one we used in the equipment shed and the root cellar. The ones I am familiar with have a center cap on the front which is the "trigger" and it is wound from the back. You cannot put the trigger in place until the spring is fully wound. Once it is wound, the trigger button will slide into place. We could get replacement trigger buttons at the Western Auto in town, or at the fire department.
That style were in the house where I grew up, built in the 1970s. I believe we had Vanguard Thermosonic ones, a brown color bell and an odd chrome finned bit around the fusible pin.
nice to see how we solved problems before computers came along. Mechanical stuff is fascinating
I would use that to hang up on boring phone calls. "Ding ding ding... Oh sh*t. sorry I HAVE to go. (hangup) " :)
You laugh, but I still use that phone. I like having a landline and all the phones connected to it were made in the 80s or earlier and have mechanical ringers. The oldest one is from the 60s (I will not give up touch tone). I really, really do not like electronic ring-tones.
You could say your "BS" detector went off.
I'm more straightforward. "I'm going now, bye" click.
That is really neat.
What a brilliant idea. I actually want one now
Nana had one. It sits on my desk now. It's fun to play with.
In the 1960's a guy came to our door selling this type of alarm. After looking over the house he suggested that we needed at least 4 of the alarms. About $300 worth. Seeing that I was showing some interest , up went the pressure. He could smell a sale. He proceeded to tell about lady just a few blocks away that had recently purchased an alarm. Why just a few days after she purchased her alarm', she had a fire and it saved her life . I just let him go. This was followed by several more stories along the same line. After listening to his sales pitch for 20 or 30 minutes, I had lots of time and very little money in those days. I asked, Oh do you get a free fire with every alarm system? He jumped up SLAMED his sales book shut and exclaimed this is not a joking matter. .Madder than hell, he couldn't get out the door fast enough. I loved door to door salesman.
Wow, $75 each.
Pre-internet era trolling was wild
That's how my mom got a Kirby vacuum cleaner ,an intense sales pitch at our home.
@@Stevie-J You had to do it in person and be ready to get punched in the face. Thanks to the internet, we are all smart ass tough guys now.
When I was in college I used to string along telemarketers. Get them talking while I folded laundry or something, thinking they had me on the hook to buy a magazine subscription or whatever, and then after 20 minutes tell them, "Well, it's been nice talking, gotta go now, bye!" and hang up. It was kind of fun, but I guess it was also a little mean.
I'm with you, I'm fascinated by just how much we were able to do with purely mechanical analog machines. Things like the Norden bombsight, the computers battleships used to aim their guns, down to fairly simple things like this, time clocks, juke boxes, and vending machines. I grew up around such things and while I'm not giving up my modern electronics, these things should be preserved.
My father owned a woodworking factory and sawmills near London, England. I remember that there were lots of those hung around the workshops near the machinery. The sawdust in the atmosphere ( this was in the 1950’s) and around the shop was a big fire hazard.
Fascinating! In general I like devices that dont need batteries - as this one clearly explains, still functioning after 60 or 70 years.
However, the modern smoke alarms are much more capable. They dont need to get warm at all for sounding the alarm, since they detect smoke not heat. And to quickly heat up that little rod above 50°C, the air needs to be significantly warmer. Meaning, the fire may be in a stage where the danger zone for smake inhalation is long passed. Crucial because most people die from the smoke, not from burns.
But for the time the Wilkinson device was sure better than nothing. And by the looks also relativly inexpensive, which is also a factor if you want that many people use it.
Well, it's better than nothing and probably a lot louder than a modern smoke alarm.
As long as the fire started in another room it would have a chance to wake u up before it spreads to other rooms.
@@tarstarkusznah not louder then the hardwire ones of like apartment building. They test mine every year and it's so loud it legit hurts your ears bad when in the same room as the alarm.
@@MRblazedBEANS I'm talking about the battery operated home models.
We've been replacing some of the ion/photoelectric smoke alarms with modern heat triggered ones in places like the kitchen and some bedrooms.
The amount of false triggering especially with photoelectric ones, has caused us to start to ignore the alarms(When they go off at 2am they become excessively annoying) and brand new ones develop problems after a year or two..
Ones you trust are better than ones you ignore.
My primary school in the UK had these in the 90s alongside modern fire alarms. Never heard one go off till today :)
Yes! Traditional mechanical devices are so much more fascinating than their electrical counterparts. Keep up the wonderful videos!
For many years, in my Mom’s house, in the furnace room, we had an electrical version of this. Rectangular and a little larger than a cigarette pack, it had an exposed bimetallic strip on the bottom. When heated, it would close a contact, connecting a single D-Cell to an electric bicycle horn that would sound continuously until the battery died, the room cooled or the whole unit was burned up.
Testing it consisted of poking the bimetallic strip with your finger. If it let out a lame croak, it was time for a new battery.
Wow. I found one of these in my attic. My dad was a firefighter so I thought it had something to do with that. I wound it up and yeah it started ringing. It still had some spring tension left and everytime I walked by it the vibrations from my footsteps would allow it to unwind a bit more and it would ding to each one of my footsteps
my parents house has a version of these. it was built in the 70s and they still function perfectly when tested... loud as hell.
Does it need to melt? Surely it just needs to soften enough for the spring tension to overcome its shear strength?
It is aready a very soft metal, to be that distorted without breaking, it will shear before melting.
It wouldn’t all be liquid when it lets go, it’d be a mix like a slushie of solid and liquid phases.
My previous house was built in 1949, and had a similar clockwork fire alarm on the kitchen ceiling. It was one of the types that had a center button trigger, but when I looked at it, it also used a fusible link to set it.
I like mechanical solutions to problems we solve otherwise nowadays as well. More of these videos are always welcome.
Nice finding Giles thank you
When my brother & I were kids, we had mechanical fire alarms in our bedroom and one in the living room. Rather than a low heat metal pin they used a plastic cap that would melt, given high enough temperature. You could also very simply pull the cap off to test and to occasionally release the spring tension. It was very loud as I remember.
Given that the percentages of each element are known, you could try testing the density of the metal in a measuring cylinder, then finding which one matches most closely.
If you don't have a measuring cylinder, but do have a long, thin tube, you can use distilled (or just soft) water and a set of scales. Mark the water level before dropping it in, the water level after and then weigh the amount of water needed to get to the upper water level by placing the cylinder on a set of scales, zeroing them and adding water to the upper mark.
I've used the latter method to find out, roughly, what certain unknown metals are from metal detecting.
I am fascinated by cardboard boxes and commercial folding cartons. I worked at the home Depot and it's literally the bread-and-butter of the dang place I really understood how many different cardboard manufacturers how much standardization there is in the industry and how awesome it is that we ship things in paper.
My mom had a mechanical fire alarm, and it worked when my mother started a grease fire, by accident.
The ones my mother had are loud
Please do a video on the history of folding boxes used to hold retail products. Watching this video, I somehow realized that I would be utterly fascinated by such a topic. 😮🤭😉
I would think that the metal pin will have slightly higher melting temperature than the actual actuation temperature. Pin will start to go soft and fail before it is actually fully molten due spring pressure pulling it apart. I can see the fire bell going off accidentally during very hot summer days, especially in kitchen when cooking, not unlike modern smoke detectors. Neat little device!
Ah yes, the old liquidus and solidus thing. I remember learning about that with regard to brazing and silver-soldering.
Of course, you're brilliant! Obviously they never actually tested the device! And no one prior to your birth knew anything about material properties! How blessed we are to be allowed to walk in your shadow!
Give people some credit that they actually knew what they were doing
@@tenchraven That gentleman over there is Mister Thepoint, and right here we have Missus Thepoint!
Congratulations on achieving over 100K subs! I enjoy your channel, very much, GIles.
I would guess the alloy of the fusible pin is Field's Metal which melts at 62ºC but with some gallium added to the lead/tin/indium alloy to lower the melting point. A similar metal was used by Leica in their 1930's black enamelled camera bodies, to fill the very fine engraving, as being more robust than paint.
When I was a kid in the 60s, a salesman came to our house and made a pitch for a similar fire alarm, but the low temp alloy was in the center of the round alarm.
Ooh! I have a similar one! It has an art decco trigger in the center of the bell, presumably for a fusible link, that holds a quarter quite nicely. It was responsible for much hilarity and mayhem in its second life.
This reminds me of a friends front door bell - that's completely mechanical as well - You wind it up and when a visitor presses the button, it rings until they let go again so a very common mechanism over here in the UK.
I remember a very similar alarm at my grandparents house... just with a bigger silver bell.. . they also had the fire bomb glass ampules filled with carbon tetrocloride... I still have one of those.
There's a family of alloys called "Cerrolow" that is available in various eutectic and non-eutectic variants, and various melting points. I would assume it is something between Cerrolow 117 and Cerrolow 136. Both seem to be used as fusible elements, although their main usage seems to be for machining fixtures.
Intersting video thanks for posting .
Fascinating stuff!
I had one of those that I played with as a kid, loved setting the thing off then making obscenely loud imitations of a firetruck. 😂
Interesting fire alarm. I installed several thermal sensors around the house and shed to augment the smoke alarms and wired them up to a loud bell). They all have 190F (87.8C) trip points. 125F (52C) seems pretty low here in the lower 48 but I guess it was find in England.
Yeah, they could go off on a hot August day in Phoenix or Palm Springs.
Are you gonna hit it with a heat gun and a thermal camera and see what it does? I think that would make an interesting video. Might also be some chemistry RUclipsrs who could collaborate on figuring out what the pin material is.
Thank you for yet another fascinating video, I truly enjoy your channel. Keep up with the great videos.
A video on a McCullough Loop fire alarm call box could be interesting. Unfortunately, I don't have one.
Your local High School Chemistry teacher would LOVE to use this as an extra credit assignment for their students. Give them some filings.
Das ist ja genial
Interesting, I really like your shorts.
and I hope you also have a great day, M Messier!
Interesting little gizmo.
It could be that it simply weakens enough at 125F that it lets go before it fails. Kind of like steel weakens dramatically long before it reaches melting point.
The spare pin would also melt in the same fire that set off the original, right … Yes or yes?
2:47 It looks like you've used a º (U+00BA, Masculine Ordinal Indicator) instead of a ° (U+00B0, Degree Sign). Some fonts render the former with that underline-looking bit, or even a double underline.
I've seen this in sweden as well! The same thing!
Ingenious. I like that🙂👍🇳🇱
I think the proper terminology for the pin slowly failing is that the metal have undergone creep, it is an issue with a lot of materials that are under constant pressure.
Neat!
Does anyone know if this was the origin of "saved by the bell"?
I love alloys that melt in your mouth, but not in your hand.
especially the cadmium ones
cadmium crème eggs
I remember these as pretty common when I was a kid. I also remember breaking one of them playing with it by forcing it to overwind the spring. Crap , I am sorry about that but dont remember who owned.
But wouldn't the spare pin melt in a fire as well?
I was thinking the same thing.
In a fire the entire device would be destroyed, so the spare is likely there for when someone breaks the pin by playing with it.
A fully mechanical, no batteries required fire alarm, fascinating.
The only possible improvement I can see to make is to replace the fusible link with a modern one such as used to hold sprinkler heads shut.
Other than that, it's pretty much perfect.
Thank you for saying 'Birming-um', not 'Birming-ham'. 👍👍
Since you can take that clip off, you could pretty easily melt and re-form the pin. A cigar lighter would be more than enough heat.
The bell, or noise producing element appears to be cast. Is it duraluminum? I can’t imagine a cast zinc bell ringing with any authority.
Fir how long does the alarm ring?
Not for use in Furnace Creek California.
You need to get a handheld XRF analyzer. It would be a perfect fit for your channel to identify the strange materials you often feature.
Probably not as effective as a smoke alarm, but I mean, still worlds better than no alarm at all.
Hopefully not advertised with material from the same company that did the ads for Wilkinson instant coffee.
My Grammy had one I played with as a kid. Nobody liked the bell. Would have been state of the art 😂
That last comment made me laugh ;p
Wouldn't the spare rod melt in a fire as well? (If left in the provided storage space, of course.)
Guaranteed to be woods metal, as they did not appreciate the danger of cadmium as much then.
But it's just spicy lead ;p
Great for making pigments that you aerosolize too!
@@theodorekorehonen Along with a nice dip applied to metal as well.
Almost certainly wood's metal, just because the other variants with indium are going to be a lot more expensive.
I want one.
I love it! Lol! It would be good for something I’m sure. Id definitely have to make a new pin so as not to use the originals
2:22 Gigly gig
.
Inside the alarm might not be the best place to store the spare low melting point pin, lol
If the original snaps off, it’s easy to find the spare
After a fire the device will be considered destroyed anyways
@ChrisAthanas why would it just snap off? This one's been intact for over half a century. most smoke and fire alarms are false alarms and the detection device should be expected to be able to be reused, but wouldn't be able to be reused in the case of this device.
@@Muonium1 looks like it could accidentally break as Gilles noted
@@Muonium1 also if it's hot enough to melt the original "fuse metal" then it's hot enough to melt the spare in the device
the thermal rod ..... metal ? or wax ?
Low melting point metal. Wax would creep much more with time, though the metal does as well.
I dont think wax would keep its shape, if its under tension for a long time. As we see even that metal has deformed a lot.
Did you not watch the video?
a new question then ... if you scratch that thermal rod with your finger nail or a metal nail ... does it break out ? , & into a regular rod material ? or some sort of rust ?
Did you watch the video? Or are you so ignorant that you don't recognize specific metals when they are name in percentages for the alloy?
Having the replacement for the melt-y part of apperatus WITH the apperatus, where it is exposed to the same kind of temperatures as the original it's replacing, strikes me as odd. Most likely the replacement pin isn't for when the alarm actually alarmed in anger, but as a replacement due to accidental breakage of the original. Methinks the alarm itself will most likely be a piece of slag after having alarmed and having saving the house occupants from the fire, anyways. Fire alarms are tragic creatures.
I'm resisting the urge to make the joke about what to click if you want to be alerted to future content from Our Own Devices.
Interesting, thank you for sharing the knowledge and the video! I always am grateful to get to see pieces and or inventions of history!
125 ℉...So if my AC breaks in August the fire alarm goes off. Not good.
Well, if your house is 125 degrees, you should probably be getting out anyway.