Volute shaped blower
Added 2023-11-02 21:14:23 +0000 UTCI made a blower with a volutes shaped housing and where the fan spins in one direction only using a weighted crank mechanism. It produces a high volume of air flow but at a lower pressure than the original. The project was a good lesson in how to make volutes, but improvements need to be made to get the RPM of the rotor up while maintaining continuous, one way rotation. Much appreciated.
Comments
So that's a good thing. The hip (axis) turns much more often than the hoola hoop (stirring hoop). In the setup I'm suggesting, the hoop does not turn at all; you just keep it pressed against the axis, moving the point where hoop and axis touch each other.
Julian Gonggrijp
2023-12-01 00:29:18 +0000 UTCOne stir of the hoop still won't equal one full rotation of the hoop though. If you get a hoola hoop and make a mark on it then do one hip rotation, the mark only moves along slightly, not a full rotation of the hoop. I could be wrong though, I'd need to test it.
Primitive Technology
2023-11-09 22:25:43 +0000 UTCNo, only the frame of reference is different. I think that by hoop rotation, you mean this: https://507movements.com/mm_034.html. Imagine that animation with the same relative motion between the gears, but while the outer ring is standing still. The inner gear will seem to spin a bit faster and roll around inside the ring. Now change your perspective again and keep the inner gear centered, but spinning at the same speed; the outer ring will be "hula hooping" around the inner gear, but its left side stays permanently on the left. This is the motion I suggest you make.
Julian Gonggrijp
2023-11-09 21:43:22 +0000 UTCSome one in the pinned comment of the video suggested a socket where the rotor rolls on the inside getting a mechanical advantage with each rotation. One stir of the socket causes a bit more revolution of the rotor. In this case the weight is still connected. It sounds like your idea a bit. Thanks.
Primitive Technology
2023-11-09 00:32:48 +0000 UTCWont the fan axis only travel a small distance with each stir of the hoop? I can see if the hoop did a whole revolution the rotor would turn many times but a stir only moves the hoop a bit around the axis. A hoop stir and hoop rotation seem to be different if I understand correctly.
Primitive Technology
2023-11-09 00:22:28 +0000 UTCRemove the counterweight. Make a hoop. Put the hoop around the fan axis, pressing a point at the inside of the hoop against the axis. Stir the hoop around the axis, keeping hoop and axis connected. The axis will spin in the opposite direction of which you're stirring. If you have a hoop with a 45 cm inner diameter and the axis is 1.5 cm thick, you will get 30 fan revolutions per one arm revolution. (I have suggested this idea to you before, but I think it escaped your attention.)
Julian Gonggrijp
2023-11-08 23:56:11 +0000 UTCOk, I'll keep it in mind. It will take some time to be able to work with clay/loam again. The weather's wet and rainy, and it's cold. Thank you.
Hizuna
2023-11-05 12:13:55 +0000 UTCThanks Amy, I'll keep it in mind for future designs. Much appreciated.
Primitive Technology
2023-11-05 09:34:15 +0000 UTCI love the firemaking, thanks! Your low head air pressure may well be the fault of the tuyere diameter being too small. Your fan is certainly moving plenty of air, but the small aperture is choking that airflow, and back pressure is stalling the fan blades. (This same thing can happen with the HVAC in a house, if you close too many vents, the air stops moving, and all the hot air starts pooling in the furnace room.) Consider pulling out that tuyere and building a duct the same size as the fan housing aperture. Maybe extend the end to a tall thin rectangle.
Amy Tobol
2023-11-05 08:54:15 +0000 UTCThis will probably be a better fit for your kiln than the small high rpm blower Hizuna. The high volume but low pressure flow would suit a wide opening fire box mouth and you could feed wood between the blower and firebox mouth. Something to consider. Much appreciated.
Primitive Technology
2023-11-05 05:41:18 +0000 UTCYes a sluice and a small wheel would work if there is enough drop. I've been thinking about an appropriate design. Much appreciated.
Primitive Technology
2023-11-05 05:39:20 +0000 UTCCool idea, with the weight and the nutshell. Only the housing now is big and "static".Might try something similar myself one day.
Hizuna
2023-11-04 23:06:09 +0000 UTCI seem to recall you making something similar to a shishi-odoshi at the creak. Maybe it was a Monjolo? Using the cane from the water filter design as pipes, you could use the power of the running water, which drove the water wheel from the creek to run your fan at a higher RPM. Excellent video, as always!!
Célia Vytrac
2023-11-04 19:41:24 +0000 UTCYes, it would be more ergonomic. Thanks.
Primitive Technology
2023-11-03 20:02:43 +0000 UTCYes, while I was experimenting with the design I tried a stick with a socket in the end where the nut shell is in the video. It works more or less the same although if the design were larger the conrod would allow clearance from the larger rotating counter weight. I think clay pulleys are feasible up to a certain size. I made a large 50 cm clay wheel once and it was wobbly, the string came off occasionally and it ended up breaking. I think 25 cm pulleys in series would be possible. Ceramic pulley wheels have been used in the past for lifting buckets in wells. Google images "Edo period ceramic wheel pulley" ,they're basically a clay disc with a groove around the out side. The hole for the wooden rotor is square so it won't slip. Thanks.
Primitive Technology
2023-11-03 20:01:18 +0000 UTCThere's an issue with bearings but if that can be solved, horizontal axis foot operated flywheel crank blower might work and be easy to operate and produce a lot power.
Tapio Peltonen
2023-11-03 15:57:16 +0000 UTClooking at your "crank" design. You could offset a "connecting rod" and have it connected to hand crank. put a counter weight at the end of the arm on the blower drive to balance it. Think of a steam locomotive drive system in reverse. You could make simple pulleys but you don't really have the woodworking tools to do that in the context of your show. Fired clay pulleys would be heavy, unbalanced, and too uneven to use. Drive belts would be no problem you have the twisted rope to do that job.
Kenneth Crips
2023-11-03 15:00:09 +0000 UTCThanks, it went through two iterations before settling on this design. The first was to use a crooked stick that sort of acted as a crank with a rock tied to it. But then the weighted log design got rid of the need for a specially shaped stick. Yes, a crank connected to a pedal would work but the fan needs to be bigger. Much appreciated.
Primitive Technology
2023-11-03 07:53:38 +0000 UTCWell done, nice design with the flywheel concept. I was thinking that the next step might be a foot powered blower. I don't know if this design could be adapted to being foot powered but something else might work being foot powered.
Sam Gordon
2023-11-03 07:36:34 +0000 UTCYes, that small water drop was able to power the monjolo. What would be good is to find a decent water fall and get it to turn a small diameter wheel to reach the really high rpm needed. Actually in the monjolo video I made a small water wheel and demonstrated the effect of water height on wheel speed ( https://youtu.be/i9TdoO2OVaA?t=43 ). The higher the fall the higher the rpm. Thanks.
Primitive Technology
2023-11-03 06:56:11 +0000 UTCWaaay back in the day you had a water-powered hammer that was very cool. Any thoughts of harnessing water power for a blower? Or for anything else? After all, water doesn't care about being tired or un-ergonomic! (Though it does care about droughts.)
EJL
2023-11-03 05:58:45 +0000 UTCThe volute housing is cool. I'll try again sometime with a better, one way rotating mechanism. The key is to get a higher rpm, in a way that's simple and durable. Thanks.
Primitive Technology
2023-11-03 03:19:32 +0000 UTCArghhhh. Such a beautiful design, too bad the results weren't as beautiful!
Theo
2023-11-03 03:11:37 +0000 UTCI'll look into it. Rubber would make useful belts for pulleys. Thanks.
Primitive Technology
2023-11-03 03:03:48 +0000 UTCI haven't watched the video yet (I'm saving it till I can watch on TV at home), but I wanted to ask if you have considered doing anything with rubber. I was reading "The Lost City of Z" by David Grann and that book mentioned that indigenous children in the Amazon had rubber balls they played with. It made me wonder if you could use latex from native figs to make rubber. There's a bit of research around about making rubber with different species of Ficus. It appears the Amazon Indians used rubber mostly for waterproofing, but I wonder if using it as a spring could improve the efficiency of some of your machines.
Robert Walter
2023-11-03 01:08:05 +0000 UTCYeah, pretty spectacular. If you see the iron smelting videos with charcoal the flames have a blue tint due to co gas. It was very tiring. The mechanism is easy to run for short periods but is harder on marathon smelts. Much appreciated.
Primitive Technology
2023-11-02 22:57:29 +0000 UTCThe least complicated way would be to make the fan diameter larger so that tip speed is relatively higher per revolution and therefore a greater air pressure produced per turn. That way you would not have to turn it as fast for the same air pressure. I actually built a 1m diameter fan but was not able to test it during this project due to time constraints (it would also need a larger housing). A 1 m fan (opposed to the 50 cm one in the video) might produce comparable air pressure to the original string driven blower according to my estimates. Aside from that, pulley and wheel mechanism could be set up but the machine would get more complex and may break down more. Much appreciated.
Primitive Technology
2023-11-02 22:54:03 +0000 UTCThe flames in the new system look so bright that it almost look special effects instead of real fire. I can see that this new system looks like require much more time and effort than the original one.
Faralis
2023-11-02 22:19:50 +0000 UTCHow interesting! Any thoughts on making it more ergonomic? Thanks for the fun video.
Ken Clark
2023-11-02 21:40:27 +0000 UTC
