Yeah and the wood being a soft and rough material but still pliable means any friction is being multiplied. I think a computer machined aluminium frame with bearings could make a huge difference along with born block and tackle. It explains why he has such a heavy draw weight with loads of energy lost on the release.
You want some really powerful self contained coil springs Jeorg? Get some rope returns for magnetic rowing machines. They're coil springs contained inside a plastic case, weigh about 1kg and have the spring pre-tensioned with two bolts sticking out so they can be indexed. Perfect for building a crossbow out of. Snapped one on my previous rowing machine and was extremely thankful I wore a face shield when trying to bend it back into its slot as the spring launched itself right into my face.
@@Zane-It Can you get coiled garage garage door springs? I've seen straight garage door springs but if they make coiled ones then that thing would be powerful AF.
I can see a few ways to improve the basic performance: First, replacing the paracord with a proper bow string. It's an ok substitute for testing, but between its weight, how much it stretches, increased friction, etc... Paracord wastes a lot of power. Likewise, I think the string stop's design interrupts the powerstroke at a crucial moment. I don't have a solution for that, but letting the string follow through might be better. Of course, as stated in the video, there's also the weight of the spring housing. anything that could be done to safely lighten them would be beneficial. Someone else also mentioned graphite powder lubrication, which would help. The one thing I think it really needs, though, is stability. the design would really benefit from either a counter weight or more likely,a slingshot style arm brace. that would improve the draw considerably.
You've been resisting metal power storage for years in your inventions- so cool to see this new chapter. (*edit*) Also if you plan on incorporating speed advantage you might also want to try the other type of torsion spring, like the kind used in say a clothes pin- they are strong and compact enough to be used for the suspension system of tanks.
I've been working on a really similar design that uses rubber torsion instead of spring coils for some fiction of mine. I love how yours looks like two yoyos strapped together to a pistol!
this can absolutely work if you replace some parts, better springs, a material to replace the blockiness of the wooden cylinders at the front, and you're already closer to a product that might feasibly have market appeal! that said, lovely work Joerg, love your videos!
I am amazed you made this considering our conversation on a previous video. The proof of concept does give us an idea of what a compact Lancehead might be like (block and tackle setups aside). Thanks for sharing this with us!
Honestly, ever since 2008 you've given me such peace of mind. They say WW4 will be fought with sticks and stones, but I will gladly be able to show you their features and it's all thanks to you.
Maybe you can make one with with a massive custom spring and some aluminum rotors for some serious power. Still keep the wooden body and all. Guaranteed you could start a Kickstarter and people would pay for the materials and the custom spring(s) and you'd have a spring bow more deadly accurate and powerful than ever seen before. I'm talking like high end compound bow power in a hand held size, if anyone can do it, it's joerg and his fan base
@Linus Fu I think he's probably right that the wooden wheels absorb too much power as they spin up. Effectively, he has a very heavy arrow he's trying to accelerate, then a tiny portion of it flies. KISS principle applies. That's why the really effective drivers of arrows use speargun rubber...minimal extra mass.
Love, that you still do these homemade inventions. Feels, like, you are really in there and you do stuff, no one thought about before. Follower since 2010 or sth. keep it up!
You are no dummy this is a fact that I and thousands of others who mainly know you through your youtube channel, will attest. But your craftsmanship along with your engineering capabilities, to me, are freaking awesome!!!
This makes me think of early firearm prototypes, the kind where it's clunky now but you can see the potential already. Stronger springs, a block and tackle system, aluminum body, and bearings to help it all run smoothly would make this a beast for its size.
Great stuff! There is definitely room for improvement here. One idea I had is that you could couple the bowstring to the springs using a non-constant gear ratio, to achieve draw characteristics similar to a compound bow. Springs linearly increase in force the more they are compressed, so it would be beneficial to counteract this with gearing, giving the springs a more or less constant force. Instead of wood, you could use 3D-printed spools for the bowstrings to reduce the weight and inertia. All of these improvements would result in a compact bow with much improved performance.
Love watching your videos even when the inventions don't necessarily work as well as you'd hoped. In the end you almost always come up with an amazing new product! Thanks for your entertaining personality and creativity
I swear this channel is being heavily shadow banned by Google. I'm noticing it's now never featured in my feeds. Gotta love amazing UA-cam where real organic popularity is replaced with AI shaftings of the the real popular content.
When you get it small enough that it fits under my left arm where I normally have my 45 I will be in the market for one. God bless you and keep you always inventing new things.
*GASP* You once said that using torsion springs wouldn't be very effective in a comment reply about this once. Idk what changed but glad to see this execution of this mechanic!
This design is actually very promising, but it needs some tweaks, and a couple add-ons. The first thing I'd go for is a wrist brace that grips the bottom of your wrist (I noticed serious downward recoil from the inertia of the spring wheels). The brace would distribute that force into your arm, which is waaaay more bouncy/force arresting than the body of the coilbow, so it can absorb the force. The second thing I'd go for is something like two or more arrow rests, one where you have it right now, and one on a rod that extends back from the pistol grip towards your elbow. Two (or three, optimally, to guarantee a smooth trajectory as it starts flying) arrow rests will guarantee the string doesn't fly up as it approaches it's resting position (which you can see in the slow motion). Third, I'd test different coil springs. The alloy you use for the springs, as well as the hardness/elastic properties the spring has can vary wildly depending on that. Trying different springs would undoubtedly yield extremely different results, specifically regarding the velocity at which the springs return to their resting state. Higher spring velocity should equal higher arrow velocity. Ideas for future iterations might include a spring that really decompresses quickly, but to compress would require a mechanical advantage (a block/tackle system). What if you could pull back the string, and lay the arrow onto a track guide that extends ~8 inches back from the pistol grip? That would be very effective, as it would stabilize the arrow, and it could have a locking lug that keeps the arrow in the "cocked" position. A crank that actuates a cocking bar would require the whole thing be a bit longer (1/2 the length of the arrow, I would assume), but this could be fine considering it's a "bullpup", which means as long as it doesn't go past the elbow, it's good. The bow release wouldn't even be a separate requirement at that point, it could be built into the trigger mechanism (admittedly, making the trigger more complex, since you'd essentially be building in the bow release). Now of course, this increases costs, and makes it harder to build, but I still think it would be very cool. Ultimately, food for thought. You've give me some ideas. I may try to build an improved version and then send you video of it in operation. I'd be honored to be included in a video or something, if I do end up doing that (my wife likely has other projects I need to work on, though). Very cool video though, I appreciate how innovative you are, it inspires me to try interesting things.
Yeah man, I think youre on to something here, mr spraeve! Some really powerful springs and ots probably amazing! That crossbow sure had serious power...
You always come up with really nice concepts, and this is no exception. You say it doesn't perform well, but I think it's pretty good for a proof of concept. There's some potential to it, and I'd really like to see an improved version.
Simple inline design: trampoline tension spring pulls cord on small side of cam- connected with large side of cam, which pulls the string. Gives the mechanical advantage of a compound system and even allows for constant draw weight and let-off.
Always a great show . Weird but good one this time too. But one thing I'd change is that it's more like an assisted sling shot that shoots arrows too. Add in that most of the power was being lost at the small arrow access at the front of the coils. Other than that I can see the concept working with your help here. Tyvm and keep it up!
Way to think out of the box. For the next rendition, what about using a bar spring steel that has lever arms. The arms could be made of your favorite strong light material. This would get the torsional mass closer to the fulcrum. Maybe add the block and tackle system as well to increase the draw, since the torsion from the metal bar would be quite small. This looks really cool in my head. Has lots of room for many renditions. Love watching your videos dude! Take care.
Interesting contraption, definitely worth playing with latex, you can change the gear ratio between inner and outer wheels or even try various cam shapes. Like a super compact compound bow.
Love it Joerg! Finally another interesting new approach from you! What I would recommend for the draw to be less awkward is to put the grip in front of the two wheels and not below it. Make the pull in line with your holding hand. For a design like this in which the pull of the strings is really linear in relation to your hand much different from a normal bow… a perfect central hold is crucial. You can space the wheels out more to be left and right of your holding hand so the hand can sit in between. Just a though. Changes the formfactor a lot but makes it way more comfortable and ergonomic to draw.
Lay both wheels flat on the same plane, so that the rotary force cancels itself out instead of pulling the bow down. Then attach a wooden bracket connecting the wheels from above to eliminate the strain and friction on the axles. This should also allow the string stopper to be made narrower, further reducing friction. Combine this with OP's suggestion of placing the handle in front of the wheels, and the end product should look and function like a bow with coils for arms. (with a perpendicular slingshot-style grip)
I built something similar. Its a spring bow like this but its a long garage door spring inside a housing that pulls a cable over a pully to push the arrow. When it fires it makes a starwars laser blaster sound from the spring retracting inside a metal tube and pushing the air out
I have a few suggestions for improvements: - Since the energy is not stored, the pistol grip puts more uneven strain on the hand than neccessary and you loose accuracy. Maybe put an axle through all the coils, so that the coils turn the axle and the axle turns the drums and you grip the axle. With a little offset between grip and axle you could balance it even more. It would make the grip a little thicker, though. In this config the arrow would accelerate very close to your arm, so you'd need arm protection! - To increase the draw length and therefore increase the power transmission phase, you could offset coils from its neighbor on each side. E.g. first the inner pair engages the axle, then the next outer pair and so on. This would require stronger coils, but would lend itself to learners or competitions, since you can change the coil package, but keep the rest the same. Having a custom grip can be really nice. - If you're super fancy, you could put a gearbox (e.g. planetary gear) inside, to replace the block and tackle.
Love All your stuff & vids Joerg !! Just wish I could get more of your stuff sent to Australia. Hope your fingers are ok & heal fast Much Love & Appreciation 🖖💛
It's got a lot of scope for development and it's performance would increase with the right materials and improving on the issues that you're already aware of.
What I’m hearing is “this can shoot heavier arrows but it will still be slow, if there was some sort of gearbox/block&tackle to change the slow power/high torque low speed to faster arrows with lower torque this design would be markedly improved upon”
Another factor in a conventional bow, the changing angle of the bow string changes the leverage between bow and arrow. As the string straightens the bow limb moves slower relative to the arrow, moving some of the kinetic energy from the bow limbs to the arrow.
I'm not into archery or slingshots (though I've put more than a few squirrels and rabbits on the table with a good old wrist rocket) but I do much enjoy machines. Really though, I'm here for your joyous laugh. Thanks for the smile today!
Yay I'm happy my comment could have been read. If the coil crossbow company makes a pistol version it would be awesome. Just need an adder sized repeating bow with magazine.
The "clock spring" used in old style wind up lawnmower starter - rather than recoil spring is what may work - if they are obtainable cheaply, very good job with the concept
Thoughts for possible improvements: Make the grip and non-rotating parts from aluminum for strength, make the rotating parts from carbon fiber to cut down the rotational mass.
Great thing about inventing and making is that, it may seem impractical at first, but there's a chance that somewhere down the road you might find away to bring it into the practical realm.
i wonder how well this would work when integrated into a gauntlet. could be interesting for mounted archery. you can hold the reigns tight until the moment you release.
That would allow him to put springs at the back and use nexus 7 speed hub from the bicycle to gain speed. It would raise price by at least 500 euros, but would be way better. This is actually something very interesting and has a lot of potential.
If you're willing to risk broken arms or fingers you could try cutting up a garage door spring and doing something with that. It also seems like you should be able to remove the temper from a regular leaf spring, twist it into a coil and temper it again to end up with something similar to what that crossbow has.
Whenever Joerg presents some new contraption there is a new band-aid on his fingers 😂🤘🏻
jorgsslingshotinjuries.quora.com/
@@Slingshotchannel only you would have a chronicle of injuries! Here's hoping you manage to stay in one piece!
@@Slingshotchannel Jörg, wo gehobelt wird, fallen Späne! :-)
Ha.. ha..ha,
do you think Jeorg edits out his more serious injuries from anyone knowing?
@@Slingshotchannel ah, yes, the Joerg injury Lore.
Maybe by lubricating the mechanism you can get more power out of that thing. Dry graphite powder does a good job in lubricating wood to wood joints.
Not the core issue tho. The main issue is too much of the energy going into movements of the mechanism rather than into the projectile itself
Gun barrel ? A long tube might guide it in one direction making for a smoother release.
Yeah and the wood being a soft and rough material but still pliable means any friction is being multiplied. I think a computer machined aluminium frame with bearings could make a huge difference along with born block and tackle. It explains why he has such a heavy draw weight with loads of energy lost on the release.
Ah yes, Joerg Sprave. German engineering distilled to its highest potency, given physical form.
German technology is the world's greatest!!
-A certain buff german cyborg anime guy
Imagine what Jörg could do if Germany had similar gun laws to the US. He'd be a one man army.
@@rebel4466 We can only dream..
You want some really powerful self contained coil springs Jeorg?
Get some rope returns for magnetic rowing machines.
They're coil springs contained inside a plastic case, weigh about 1kg and have the spring pre-tensioned with two bolts sticking out so they can be indexed. Perfect for building a crossbow out of.
Snapped one on my previous rowing machine and was extremely thankful I wore a face shield when trying to bend it back into its slot as the spring launched itself right into my face.
Good idea or better yet an automatic garage door opening spring.
@@Zane-It Can you get coiled garage garage door springs?
I've seen straight garage door springs but if they make coiled ones then that thing would be powerful AF.
@@daviddavidson2357 yes I have seen them in southern California.
@@Zane-It How big are they? If you could mount them on a crossbow frame you'd have one cool crossbow.
@@daviddavidson2357 the matinance people didn't let me get close to the spring in fear that it would hurt me so I couldn't tell you how big it was.
I can see a few ways to improve the basic performance: First, replacing the paracord with a proper bow string. It's an ok substitute for testing, but between its weight, how much it stretches, increased friction, etc... Paracord wastes a lot of power. Likewise, I think the string stop's design interrupts the powerstroke at a crucial moment. I don't have a solution for that, but letting the string follow through might be better. Of course, as stated in the video, there's also the weight of the spring housing. anything that could be done to safely lighten them would be beneficial. Someone else also mentioned graphite powder lubrication, which would help.
The one thing I think it really needs, though, is stability. the design would really benefit from either a counter weight or more likely,a slingshot style arm brace. that would improve the draw considerably.
You've been resisting metal power storage for years in your inventions- so cool to see this new chapter. (*edit*) Also if you plan on incorporating speed advantage you might also want to try the other type of torsion spring, like the kind used in say a clothes pin- they are strong and compact enough to be used for the suspension system of tanks.
I was thinking, mouse trap springs myself, along with a shorter bolt.
I've been working on a really similar design that uses rubber torsion instead of spring coils for some fiction of mine. I love how yours looks like two yoyos strapped together to a pistol!
this can absolutely work if you replace some parts, better springs, a material to replace the blockiness of the wooden cylinders at the front,
and you're already closer to a product that might feasibly have market appeal!
that said, lovely work Joerg, love your videos!
AWESOME PROJECT Joerg!
I was wondering how to create something like this - smaller than a crossbow but with more or less the same power
Thanks!
Hey, thanks for that! Super cool.
i love that this wholesome german man has been making crossbows, slingshots, whatever for more than 6-7 years!
You might want to take a look at air powered "object acceleration devices"*
_*this term is sponsored by your Bundesresgierung_
such contraptions do exist and are chemically powered.
I am amazed you made this considering our conversation on a previous video. The proof of concept does give us an idea of what a compact Lancehead might be like (block and tackle setups aside). Thanks for sharing this with us!
Honestly, ever since 2008 you've given me such peace of mind. They say WW4 will be fought with sticks and stones, but I will gladly be able to show you their features and it's all thanks to you.
Cool idea. I can clearly see its instability from not connecting the "bow" to the back of the arrow via a wide 3-point triangle. Amazing design!
Maybe you can make one with with a massive custom spring and some aluminum rotors for some serious power. Still keep the wooden body and all. Guaranteed you could start a Kickstarter and people would pay for the materials and the custom spring(s) and you'd have a spring bow more deadly accurate and powerful than ever seen before. I'm talking like high end compound bow power in a hand held size, if anyone can do it, it's joerg and his fan base
Watching his hand shake, I immediately thought of a wrist brace.
@@ianhelyar9553 oh yeah, like the have it as a gauntlet or wrist mounted
@Linus Fu I think he's probably right that the wooden wheels absorb too much power as they spin up. Effectively, he has a very heavy arrow he's trying to accelerate, then a tiny portion of it flies. KISS principle applies. That's why the really effective drivers of arrows use speargun rubber...minimal extra mass.
I'm about to sleep and this pops up.
Let's have our priorities straight.
Love, that you still do these homemade inventions. Feels, like, you are really in there and you do stuff, no one thought about before. Follower since 2010 or sth. keep it up!
You are no dummy this is a fact that I and thousands of others who mainly know you through your youtube channel, will attest. But your craftsmanship along with your engineering capabilities, to me, are freaking awesome!!!
This makes me think of early firearm prototypes, the kind where it's clunky now but you can see the potential already. Stronger springs, a block and tackle system, aluminum body, and bearings to help it all run smoothly would make this a beast for its size.
Joerg, You're a GENIUS! I watched your channel for years and love all of your inventions & modifications. Keep up the good work.
I agree, those type of springs give a constant draw force curve and in theory could have 100% efficiency. Great build my friend 👏
You're my favorite still living inventor, always love watching what you come up with. Brilliant designs
Great stuff! There is definitely room for improvement here. One idea I had is that you could couple the bowstring to the springs using a non-constant gear ratio, to achieve draw characteristics similar to a compound bow. Springs linearly increase in force the more they are compressed, so it would be beneficial to counteract this with gearing, giving the springs a more or less constant force. Instead of wood, you could use 3D-printed spools for the bowstrings to reduce the weight and inertia. All of these improvements would result in a compact bow with much improved performance.
whenever I watch one of your videos it gives much joy because of how positive you are.
Love watching your videos even when the inventions don't necessarily work as well as you'd hoped. In the end you almost always come up with an amazing new product! Thanks for your entertaining personality and creativity
Another great video Joerg! Your videos never fall to bring a smile to my face! At the same time informing your audience! So thank you once again!
I swear this channel is being heavily shadow banned by Google. I'm noticing it's now never featured in my feeds. Gotta love amazing UA-cam where real organic popularity is replaced with AI shaftings of the the real popular content.
UA-cam favors channels that advertisers don't fear. It's playing dirty, but they make more money by suggesting channels that UA-cam can sell ads on.
That's absolutely true, I always have to manually come to the channel because YT treats it almost as if I'm not subscribed at all.
The over lords don't want any common to have any resemblance of self defence
Can't have peasants making homemade weaponry in the (post) apocalypse.
You never cease to amaze me with your ideas.
I really love the way he talks! It's the main reason I watch. You can feel his passion for his gear in his voice :)
Seriously my favorite human I've ever seen! Absolutely love all your inventions!
I always loved this guy's engineering skills. Great video!!!
Im so glad you never strayed from your original content. Your rubberized weapons are all deadly and amazing
Bloopers are a great addition... Love your vids.. You are an amazing person. Thank you. Rolf
the engineering and craftsmanship is spot on as usual
Very Nice Joerg! Thanks for showing us.
I love it! May be my favorite thing you’ve made so far.
Man fühlt einfach den Spaß mit dir.
Sehr brillant gemacht. We love it
When you get it small enough that it fits under my left arm where I normally have my 45 I will be in the market for one. God bless you and keep you always inventing new things.
Thanks for all the effort you put into these
Great fun 👍 always a laugh too
Cheers
That little thing is freaking awesome. These things are why I love the slingshot channel.
Reminds me of the Slingshots that you use to showcase back in the day. Amazing.
Wow i think you really have the beginnings of something with that. Well done.
You never ceace yo amaze me with your builds, love it!
This is awesome! If you added a lever in the handle on a ratchet you lock it and rest like a compound bow
*GASP* You once said that using torsion springs wouldn't be very effective in a comment reply about this once. Idk what changed but glad to see this execution of this mechanic!
The spinning of the disc looks like it has a lot of friction!
Great looking bow
This design is actually very promising, but it needs some tweaks, and a couple add-ons. The first thing I'd go for is a wrist brace that grips the bottom of your wrist (I noticed serious downward recoil from the inertia of the spring wheels). The brace would distribute that force into your arm, which is waaaay more bouncy/force arresting than the body of the coilbow, so it can absorb the force.
The second thing I'd go for is something like two or more arrow rests, one where you have it right now, and one on a rod that extends back from the pistol grip towards your elbow. Two (or three, optimally, to guarantee a smooth trajectory as it starts flying) arrow rests will guarantee the string doesn't fly up as it approaches it's resting position (which you can see in the slow motion).
Third, I'd test different coil springs. The alloy you use for the springs, as well as the hardness/elastic properties the spring has can vary wildly depending on that. Trying different springs would undoubtedly yield extremely different results, specifically regarding the velocity at which the springs return to their resting state. Higher spring velocity should equal higher arrow velocity.
Ideas for future iterations might include a spring that really decompresses quickly, but to compress would require a mechanical advantage (a block/tackle system). What if you could pull back the string, and lay the arrow onto a track guide that extends ~8 inches back from the pistol grip? That would be very effective, as it would stabilize the arrow, and it could have a locking lug that keeps the arrow in the "cocked" position. A crank that actuates a cocking bar would require the whole thing be a bit longer (1/2 the length of the arrow, I would assume), but this could be fine considering it's a "bullpup", which means as long as it doesn't go past the elbow, it's good.
The bow release wouldn't even be a separate requirement at that point, it could be built into the trigger mechanism (admittedly, making the trigger more complex, since you'd essentially be building in the bow release). Now of course, this increases costs, and makes it harder to build, but I still think it would be very cool.
Ultimately, food for thought. You've give me some ideas. I may try to build an improved version and then send you video of it in operation. I'd be honored to be included in a video or something, if I do end up doing that (my wife likely has other projects I need to work on, though).
Very cool video though, I appreciate how innovative you are, it inspires me to try interesting things.
10:53 "and it's entirely powered by..."
PAIN
Thanks for another banger video! I don't care what it is you make. I always enjoy watching your videos.
Love these creative builds!
You are one of my all time favorite UA-cam pros
You are an awesome mad scientist. I love your unique way of thinking.
3:02 so true, I don't recall ever feeling so much agression from repairing anything else
This is amazing. I literally cheered when arrow managed to bite in the target!
And again an genius idea. Thanks for sharing. I'm eager to see the evolutions to come.
Weekend Stuff
Yeah man, I think youre on to something here, mr spraeve! Some really powerful springs and ots probably amazing! That crossbow sure had serious power...
Brilliant and humorous, thanks Joerg
Brilliant!
That looks fun!
You always come up with really nice concepts, and this is no exception. You say it doesn't perform well, but I think it's pretty good for a proof of concept. There's some potential to it, and I'd really like to see an improved version.
Such a badass. A true legend at work. Always love seeing the child like happiness on his face.
Thank you Joerg! This video is entertaining and informative!
I have been fantasizing about a weapon of this type for years now... THANK YOU!
Simple inline design: trampoline tension spring pulls cord on small side of cam- connected with large side of cam, which pulls the string. Gives the mechanical advantage of a compound system and even allows for constant draw weight and let-off.
This is just a slingshot.
The lancer is just a really fancy slingshot.
I will never unsee this.
Always a great show . Weird but good one this time too. But one thing I'd change is that it's more like an assisted sling shot that shoots arrows too. Add in that most of the power was being lost at the small arrow access at the front of the coils. Other than that I can see the concept working with your help here. Tyvm and keep it up!
It is ABSOLUTELY beautiful!😲👌
Way to think out of the box.
For the next rendition, what about using a bar spring steel that has lever arms. The arms could be made of your favorite strong light material. This would get the torsional mass closer to the fulcrum. Maybe add the block and tackle system as well to increase the draw, since the torsion from the metal bar would be quite small. This looks really cool in my head. Has lots of room for many renditions.
Love watching your videos dude! Take care.
Seriously cool build!
This spring tech, with the geometry and wheels of a compound bow, would be awesome.
Interesting contraption, definitely worth playing with latex, you can change the gear ratio between inner and outer wheels or even try various cam shapes. Like a super compact compound bow.
Love it Joerg! Finally another interesting new approach from you! What I would recommend for the draw to be less awkward is to put the grip in front of the two wheels and not below it. Make the pull in line with your holding hand. For a design like this in which the pull of the strings is really linear in relation to your hand much different from a normal bow… a perfect central hold is crucial. You can space the wheels out more to be left and right of your holding hand so the hand can sit in between. Just a though. Changes the formfactor a lot but makes it way more comfortable and ergonomic to draw.
Lay both wheels flat on the same plane, so that the rotary force cancels itself out instead of pulling the bow down. Then attach a wooden bracket connecting the wheels from above to eliminate the strain and friction on the axles. This should also allow the string stopper to be made narrower, further reducing friction. Combine this with OP's suggestion of placing the handle in front of the wheels, and the end product should look and function like a bow with coils for arms. (with a perpendicular slingshot-style grip)
I built something similar. Its a spring bow like this but its a long garage door spring inside a housing that pulls a cable over a pully to push the arrow. When it fires it makes a starwars laser blaster sound from the spring retracting inside a metal tube and pushing the air out
I have a few suggestions for improvements:
- Since the energy is not stored, the pistol grip puts more uneven strain on the hand than neccessary and you loose accuracy. Maybe put an axle through all the coils, so that the coils turn the axle and the axle turns the drums and you grip the axle. With a little offset between grip and axle you could balance it even more. It would make the grip a little thicker, though. In this config the arrow would accelerate very close to your arm, so you'd need arm protection!
- To increase the draw length and therefore increase the power transmission phase, you could offset coils from its neighbor on each side. E.g. first the inner pair engages the axle, then the next outer pair and so on. This would require stronger coils, but would lend itself to learners or competitions, since you can change the coil package, but keep the rest the same. Having a custom grip can be really nice.
- If you're super fancy, you could put a gearbox (e.g. planetary gear) inside, to replace the block and tackle.
Keep innovating Joerg! Love your imitation of a lawnmower reel,"VVVVOOOOOOOVV!"
Love All your stuff & vids Joerg !! Just wish I could get more of your stuff sent to Australia. Hope your fingers are ok & heal fast Much Love & Appreciation 🖖💛
Lubrication of the springs and wood-on-wood joints and/ or making them out of harder wood might help the performance a bit.
Also, YES BLOOPERS!
It's got a lot of scope for development and it's performance would increase with the right materials and improving on the issues that you're already aware of.
I've been waiting for this!!!
What I’m hearing is
“this can shoot heavier arrows but it will still be slow, if there was some sort of gearbox/block&tackle to change the slow power/high torque low speed to faster arrows with lower torque this design would be markedly improved upon”
:D also alle Jahre schau ich mir mal ein Video von dir an und bin erstaunt über eine Fortschritte, great work!
Thank you dude. Marvelous
Excellent stuff man
With bearings and better springs and obviously a more robust body you might have a real winner there!
Another factor in a conventional bow, the changing angle of the bow string changes the leverage between bow and arrow. As the string straightens the bow limb moves slower relative to the arrow, moving some of the kinetic energy from the bow limbs to the arrow.
Great to see bloopers at the end 🤣 he's a realist 😀
I'm not into archery or slingshots (though I've put more than a few squirrels and rabbits on the table with a good old wrist rocket) but I do much enjoy machines. Really though, I'm here for your joyous laugh.
Thanks for the smile today!
Hey Joerg, you should definitely try door handle springs, some of them are pretty hard and small.
Improve this, man! For sure! This has potential for real!! Just make one that fires smaller bolts with highest powered springs, I need this!
Yay I'm happy my comment could have been read. If the coil crossbow company makes a pistol version it would be awesome. Just need an adder sized repeating bow with magazine.
I love your show its fun to watch
The "clock spring" used in old style wind up lawnmower starter - rather than recoil spring is what may work - if they are obtainable cheaply, very good job with the concept
I'd love to see a combination of this with the Adder, along with your magazine technology.
Love your vids man
Thoughts for possible improvements: Make the grip and non-rotating parts from aluminum for strength, make the rotating parts from carbon fiber to cut down the rotational mass.
Great thing about inventing and making is that, it may seem impractical at first, but there's a chance that somewhere down the road you might find away to bring it into the practical realm.
Great concept you have there . Hmmm you have me thinking, I'll keep you posted .
Love your work
Brilliant man!!
i wonder how well this would work when integrated into a gauntlet.
could be interesting for mounted archery.
you can hold the reigns tight until the moment you release.
You'd need a steel bolt and a retracting magnet as part of the firing mechanism to stop it being thrown off by the horse beats.
Could you build a variant with an instant legolas?
Then you could use the finger rest at the end to help keep it stable?
A SIL on this would be cool.
That would allow him to put springs at the back and use nexus 7 speed hub from the bicycle to gain speed. It would raise price by at least 500 euros, but would be way better. This is actually something very interesting and has a lot of potential.
I would love to see more!
If you're willing to risk broken arms or fingers you could try cutting up a garage door spring and doing something with that.
It also seems like you should be able to remove the temper from a regular leaf spring, twist it into a coil and temper it again to end up with something similar to what that crossbow has.