Garage Elevator Emergency Brake Otis Inspired For Attic Lift in Minneapolis
Vložit
- čas přidán 4. 06. 2024
- When we posted the first video, we were really surprised at the response, at this point the original video is approaching 800k views. The comments were amazing. A percentage of them were about safety.
We designed and built this emergency brake modeled in a way after the original braking system designed by Elijah Otis. We don’t use a ratchet system or teeth because we don’t have that capability. We designed a system that is actuated if the hoist rope loses tension for any reason. If this were to happen, “jamming rods” will be pulled downward on one end, and pivot upwards on the other end. The upward moving side of the rods will contact the soft rough sided cedar planks we attached to the inside of the rails. The friction between the rough wood and the sharp edges of the jamming rods causes the rods to grab the wood and travel further upward as the carriage tries to travel downward, and the carriage jams between the Unistrut rails lined with the wood planks.
To test it, we engaged the brake and placed 300lbs of sandbags on it and it didn’t budge. Pretty cool. I hope you enjoyed the video and watch for our next one when we load it up with 300lbs of sand again, tie it off with a rope and then cut the rope to see what it does in an actual free fall possibility. Should be interesting. As always, please note that we are not experts. When we do this ourselves and use it ourselves, we know what we built, and we watch for any safety hazards. Please be very careful if you decide to do anything we talk about in our videos. Be safe and overbuild for strength. Thank you. Brian and Mitch - Jak na to + styl
Congratulations you are the first person that has built a elevator in there garage that has safeties on the elevator. I am a retired elevator mechanic as we are called I have worked in the treads for 45 years on everything on elevators with wooden rails to the most modern computer controlled systems. That took a lot of engineering on your part . Congratulations again.
Hey thank you Kenneth. That really means a lot to us. Your work experiences is to be commended! Thank you again.
Outstanding home project. Good job on safety aspect.
Thank you Stever!
Excellent job. First time I have seen a home elevator with this type of brake.
Yes, thank you. I was thinking... and that’s how stuff like this happens 🙂
Another great video by you on the safety of a DIY cable hoist lift. I love your safety solution. And like someone else said, you are really the first one taking safety more serious on DIY elevators. Thank you again.
Thank you. We appreciate the comment. Take care!
We had a lot of fun making this video. Please let us know if you have any questions or comments for us. We love the discussions that formed on all the other videos. They are what inspire us to make more. On a side note, who do you all have for the Super Bowl?
I've got the Bucs, Tom Brady is insane.
@@XxRAWINSANITYxX I'm with this guy
I know it's been a year, but I have a question: Would it be better to add just enough slack to the fall arresters to make sure the brake engages first? I guess the concern would be the arresters somehow keeping the brake from engaging completely, allowing it to slide before it's able to dig in to the wood. My thought is that adding an inch (or small amount) to the arrester straps over the amount of slack required to engage the brake would give the brake the first chance at stopping the lift, with the arresters as a fallback
You could have the arresters mounted in a vertical slot upstairs, supported during normal operation by a sacrificial piece of wood or something that would break under load and allow the arrester mount to move to the bottom of the slot where it would be fully supported. That way, if the brake fails or slides fast enough (carving into the wood?) the arrester should engage.
Really awesome design though, I really need one of these in my garage :)
@@DakotaHawkins you should watch the brake test video. The brake stopped the carriage with a 300lb load immediately. Really cool.
thank you very much
Excellent effort and excellent advice
The picture is completed in my head
God bless you
God bless you too my friend!
my friend is a elevator builder/installer and safety inspector at Otis Netherlands and i send him a link to your video,that safety catch is pretty genius ,so now you got a double safety mechanism, great job and subscribed
Thank you Leon!
That is so cool. Thank you. High praise from a credentialed source! I’m going to pin this comment!
Brilliant, well thought out Gentlemen.
I built my elevator brake using a Cadillacs rear disc brake caliper that had a manual parking brake cable built into it.
Then I mounted an aluminum 3 inch W 1/4 " thick flat bar stock mounted verticle on the wall behind the elevator to act like a brake rotor. The brake caliper is attached to the elevator basket. The brakes parking cable is spring loaded (old garage door spring) to be opperated with no cable tension. And like you have it set up so that the lifting cable pulls the parking brake calbe attached to a lifting stop thereby release clamping pressure just before it lifts the basket. Should the cable break the spring pressure will pull the calipers parking break system to pinch the flat bar stock, thus arresting the fall of the basket.
So simple and no hydraulics needed to operate.
That is awesome. I was thinking of using a caliper like that but I wasn’t sure if would have enough friction to stop a fall. I’m happy to hear your idea worked! That’s awesome!
Bloody Clever.. :)) Cheers from Michael Australia
Cheers. Love our Australian brothers and sisters of freedom!
Very impressive job, Thank you for sharing all your ideas and research
You’re welcome. It’s fun. Thank you for watching.
Very nice design! If I ever build one I will put braking like this on it.
This is a fantastic idea. Thank you for making this video. We have a very tiny cabin and this would be perfect for it.😊
I love the evolution, although I’m more impressed with your attitudes and willingness to keep taking it to the next level!
Thank you buddy. That’s very nice of you to say.
This is fantastic
Thank you Pappy!
thank u. thank u. thank u
Great. Job. American ingenuity at its Best
Thank you. I agree.
This is cool.. And Idea.. Bolt washers to the inner channel so as it slides down, it will hit those washers and present more resistance than the soft wood in case it builds up too much momentum to function otherwise?
So cool!!!
Gracias Senorita
Very cool great job guys!!!
Thanks Eric!
Thank you Eric!
Absolutely brilliant and the entire 3 part series was extraordinarily perfect in every respect, design, construction, usability and of course striving to provide a fail safe safety system. Your video production and editing is excellent in every respect.
To read that you have over 800,000 views and growing is a testament to your ingenuity and attention to every detail. Most importantly you read the comments and respond to many offering explanations and comments which viewers like me and others very much appreciate.
What’s next? I can’t wait.
Thank you, man! What’s next is a crash test! We’re going to tie off the hoist with a rope a few feet off the ground, disconnect the hoist and the fall arresters, pile 300lbs of sand on it again and cut the rope! I may do one without the brake (for effect) and one with the brake and hope it holds!
Also, I spec’d out some springs to replace the bungees on a site called thespringstore.com. So I’ll be installing them to see if I got it right. The bungees are temporary to see if the concept would work. Thank you again. Take care. B
Thank you Brian! This comment made my day. As my dad mentioned, we do have some cool stuff coming up so stay tuned!
Good to see you are safety conscious. You have to upgrade from bungies though and I'm sure you will. Great job !
We did. Spec’d out some springs from an online spring store. Work great.
Impressive. I've been looking into building something similar for myself. I hadn't thought of including any safety mechanism (probably still won't, I understand the risks) but I like that you read all the safety sally comments and adapted.
Truth be told, I only did it because I thought it would be cool. Once I had the idea, I had to create it to see if it would work 🙂
Yup excellent with the safety feature!! Unless your are ready to catch yourself dropping 7ft or so this is the way to go!!
Been thinking of something like this in my garage. Only I don't have a lot of head room above. At least 36 inch square. Maybe include combination safety handrail/loading ramp. That way I can use hand truck to load, push roller chests onto it easier.
Sounds like a terrific idea.
I love it. Not so sure I'd go so overboard on safety for something which is cargo only, lol. But cool cool! I think you might have let some comments get to you. Nice engineering. I'd ride it!
I just like to do stuff like this. Once I had the thought in my head, I had to do it.
Great job on installing a very effective brake. What angle from horizontal are the brake bars engaging the 2 x 4’s ?
Brian and Mitch .. you guys are awesome! Thank you for posting this video! I'm needing to build an elevator for my wife and have looked at a number of videos and just stumbled upon yours. Seems this just posted. I'll look at your other(s). So my greatest concerns have also been safety. Lots of great idea on CZcams, lots of quick and dirty solutions but far too few safety considerations for me. Thank you again for your diligence. One persistent thought I've had (as a retired engineer) is the eventuality of material fatigue and how to minimize those risks. I'm thinking specifically about the myriad of possible failures in the typical hoist linkage system. Perhaps far fetched would be any unobservable mfg'n defect in the eyebolt carriage hoist cable eyebolt, a crack in the cable crimp fitting, etc. Any potential failure mode that is unobservable. I've imagined constructions that use aircraft quality parts which of course in a game changer. So for me I think I'll use two eyebolts on the carriage and re-secure the cable crimps with clamps. I've thought about dual hoists (cables) or a hoist that could accommodate two cables but I think your braking system is enough. Any other thoughts? Thankful and appreciative.
I like the double eye bolt idea. We originally used a cast iron eye bolt and then one of our viewers pointed out how low the load rating on a cast iron eye bolt is. In our "modifying for safety" video, we replaced the cast iron bolt with a forged iron bolt with a much higher rating. And as we mentioned, we are pretty confident with the fall arresters, but decided to make this brake because why not?
@@mitchkee_ Absolutely. I saw your comments about changing the eyebolt. Good deal. Love the fall arresters too. Adding the Otis-style lock totally puts a lock on this entire project (pun intended). This is without a doubt the best lift I've seen yet. I'll do this for sure on mine. You deserve a CZcams award of some kind! haha Thanks again. Keep posting!
Jeff Brown That makes us really happy to hear. The project itself is a blast to work on, so you will enjoy building it for sure.
Awesome series. Would be cool to see same test with the arrestors. Would they work as effectively? I like the idea of having redundant safety mechanisms but curious how the arrestors would work in similar test. Thanks for your consideration.
Great video, like you, I think safety and over-building s very important for a DIY project like this. You mentioned that the angle of the jamming bars is critical, however, you did not note what that angle is, can you please share the angle that the jamming bars need to be? Thanks
Have you considered an auto stop i.e. electrical power auto shut of; for when the base touches the ground. Thereby allowing the elevator to always come to a gentle stop.
I can imagine such a shut of would be easy to achieve but how do we re-energise the hoist when we need to raise it again.
I don’t understand the belts at the side how it’s work? Would you can explain me please?
Is that usable 4 whlchaire?
I would like to see how you maid the BRAKE?
Congratulations on the success of your elevator braking mechanism! I am a retired mechanical engineer and my brother wants to build one of these elevators for his garage. He asked me for some advice as to my impressions of your videos. I have to confess I was a bit skeptical about whether your mechanism could be deemed sound design in that I know the extent of calculations and variables involved in determining for example, that there would be sufficient lateral force and frictional effect of the jam bars onto the wood on either side to produce the necessary arresting effect to stop the platform dropping (and not simply gouge the wood as it descended, scraping a layer off the vertical wood surface, etc.) as well as the exact geometry required to produce the correct sideways forces to effect the necessary braking action (not to mention the possibility that the sideways forces might dislodge the vertical wood and rail systems pushing them outward and further compromising the rail-roller systems).
Having viewed your failure demonstration, I am now adequately convinced in the soundness of your design! (I am wondering if you had to do some iterations of the geometry in order to get the dimensions correct???) Now that you have failure tested your mechanism, it becomes a bit of a moot point as to the precise calculations of the lateral forces required, coefficients of friction of steel-on-wood, etc... Your design has stood the ultimate test - it works under demonstrated failure conditions! Again, congratulations!
I am wondering if you would be open to sharing the dimensions of your mechanism components? Absent this, I am sure it would take considerable trial-and-error to get the geometry just right! I would be extremely grateful if you would be kind enough in this regard! I am subscribed to your videos so I shall be looking for any further innovations that you might come up with.
Thank you and all the very best,
Leo Quigley
Newfoundland, Canada
I just read one of your replies to a reader who asked for details and I understand completely that every project has its own dimensions, conditions, etc. but the geometry should be able to be scaled to suit any size project. Hoping you can offer some details on YOUR particular build at least!
I am really your friend, Mitchkee
Ty Town!
Do you have a complete list of materials and links for the whole project? Thanks I have a use for one of these in two places.
No. Sorry. I wouldn’t post something like that any since every application is different and you will have to make your own assessment regarding the existing structure, safety concerns, etc.
How did you frame out the opening in the ceiling?
It’s a pretty straight forward boxing procedure.
I'm interested to know why you switched from the fall arrester to this? Seemed like a simple concept. This works great but just curious.
Curiosity and tinkering. Once the idea struck me I had to work it out to see if it would work.
Can you make another video showing how it would look if you covered the exposed wood? Can you make it more beautiful by adding some type of light-weight finish, so that it does not cause it to way too much?
I’ll see what I can do. Is there a color or finish you would prefer. I’m thinking ceramic tile is out of the question.
@@theelevator3615 Can you make it with a very lightweight metal? Can you show your audience that a professional-looking elevator is possible to make? Try to make something that Otis would want to sell to homeowners.
Bungee cords have a limited life. Steel springs would be beter, and not a great deal more costly. Agree?
Yes, for sure. Especially in this climate. I will be swapping to springs when I get time to spec out what I need. They only trigger the mechanism so I’m comfortable using them as an interim solution. Thank you for the great comment!
Nah..I will take the time to make steel rails for the dogs to be engaged. I would not trust this setup to bite into the wood. Great thought but I've seen elevator failures.
GREAT JOB, ONE COMMENT, THE 2X4'S THAT SUPPORT THE WENCH SHOULD BE BUILT LIKE A HEADER OR FLECH BEAM THAT IS IN STRESS
TO AVOID SAGGING. BUT, I MUST SAY ,, ONE HELL OF A GREAT JOB !!!! I NEED ONE IN MY WAREHOUSE AND THIS IS WHAT I'M GOING TO USE ......
THANKS
Thank you. Technically speaking, you’re not wrong about the header boards. But I did that for a reason, the large holes I had to drill to fasten the strut/motor. That header will support 5 times the weight I will ever put on it. Plus, they are glued and screwed, and from an engineering standpoint, eliminating the shift, which gives it the strength of a solid beam.
Well.......imitation is a purest form of flattery. Looks like Jay Bates copied your design almost to a ‘T,’ except he used his giant CNC plywood cutter to make the platform.
Thank you. I don’t know who Jay Bates is, but good for him. Someone with a CNC plasma cutter could do some great things with this brake design!
First comment again!!! Woohoo!!!!!!!!!!!!!!!!!!!!!!!!
Thank you!
Look again haha
I'm surprised Building and safety didnt make you get a permit and do a drop test and make you reapply for a inspection every couple of years.
It all depends on what it is called. I would say it is a dumb waiter. An elevator requires inspection a man lift doesn’t. As pointed out in his videos you should never ride this, like he does haha. Like I would too.
Lol my elevator, my risk. Seriously, I have confidence in what I built, and I am aware of the various hazards like pinch points etc. But I always tell others to overbuild it for strength and be careful operating it. I’ll respond to Pha King and I’m wondering if that’s a real name.
Hi Pha, I’m not sure if you’re in the U.S. or not. We have a lot more freedom here. We are not a nanny state, yet. We have regulations but there are no inspections unless you sell the home, or for other reasons under local jurisdiction. Kurtis is right. I will call it a dumb waiter if ever questioned.
@@theelevator3615 don't say his name out loud, it might sound bad lol
@@papakurt862 😂
OMG bro , enough safety already . your not going up 19 floors ! Stop listening to people that just want you to spend your money .
Your breaks are no good!! The most likely break point in your setup is the hook. The way you have it will only work if the cable breaks or your winch malfunctions. If the hook or anything below fails your breaks will not engage!
“No good” is pretty harsh considering the thought that has gone into this project. Maybe, one could say that if he relocated a fall arrestor to the bottom deck platform, he will be covered in an absolute worst case scenario which would be the rails failing. As long as the fall arrestor(s) is attached a different structure like the roof rafters, he will be fine. The weak link is most likely the cable and the attachment point. Just my .02 Bc that’s about what it’s worth!
The brake is sound. You are no right. The brake will engage whenever there is a loss of tension on the cable. Period. Maybe you should watch the videos again sir.
I bet the Chinese will copy that and sell it for $16. The problem with that is, the square steel tubing will be substituted by bamboo.
And the remaining brake system will be plastic. Coming to a Harbor Freight near your! 🤦🏼♂️
Lol. You’re probably right!
@@jeffbrown7246 you’re are probably right too!
Your elevator brake design is not inspired enough by Otis, in fact there is scant similarity between Otis's original design and your dangerously poor design (ref: en.wikipedia.org/wiki/Elisha_Otis ). Your design relies on cheap bungee cords, prone-to-slip cable clamps and a suspect brake scheme. The main thing you did not do, but that Otis did, was that his lift cable was connected directly to a large, sturdy and relatively stiff leaf spring that was bolted at either end to the beam that lifted the elevator car.
Your device connects the lift cable directly to the car and not to the spring as Otis did. The way that your main lift cable applies a restraining upward force to your bungee cords, and thus keeping the brake mechanism in the off condition, looks sloppy with way too many failure prone cables and cable clamps.
In Otis's design, when the lift cable snapped, the big leaf spring would almost instantaneously push down on two mirror image L-shaped linkages (pivot points connected to the elevator car) which caused the linkages outer ends to swing outwards and engage two ratchets (linear pawls) that flanked the elevator car on both sides and ran the height of the elevator range.
Otis's device provides a much more positive locking action than your design that relies on metal gouging into a two-by-four. The fact that you had to install stops on the max travel of your brake arms indicates why your design is unreliable.
Additionally, when designing an elevator car brake mechanism, you have to account for shock loading, meaning that the real force to stop an elevator car about to pummel downwards is actually much more than the actual weight of the car and its occupants.
In fact, if one drops a weight from a zero height above a platform, the platform will briefly feel a force two times greater than the weight. Even Otis's design did not engage absolutely instantaneously, meaning he had to design for a shock load much larger than 2X.
The Elisha Otis Wikipedia page shows a schematic from Otis's patent that clearly shows everything, but does not show the leaf spring too clearly, however, the web page also shows an illustration from the 1853 NY Worlds Fair, where Otis demonstrated this concept and this figure shows the leaf spring more clearly.
A real brake design must include some engineering mechanics of materials math to show that the system elements can withstand all of the forces they would be subjected to during a real emergency. Moreover, it is common to use a safety factor of at least 5 when designing devices that can cause harm to human life & limb (multiply the max car + occupant weight by the shock load factor and then multiply this by 5 and then design a system to handle that). You can't just do a couple tests that seem to work and pronounce "job done". You have to math it out!