Spring loaded nut tool on Kickstarter

sean.haynes wrote:It weighs 4 1/2oz's.. It also doesn't look to be that strong. Great idea from a designer/climber but he really needs to source funding for further research and development. He doesn't talk about any force that the little hammer can generate. This thing doesn't look like it would do much if you really get pro jammed. Would be cool if someone picked up on the idea and helped him out.

I've been trying to figure out a way to measure and compare the force LittleHammer can produce. This is beyond any equipment I have access to, so I just played with the spring pressure, travel, and impact weight till it worked. Low tech but effective.

I have been talking to a bigger climbing gear company about partnering, it's more the scale of distribution I'm worried about but the design will evolve with a partner or not, feedback from the Kickstarter batch will help us there. Anyway the company's engineers are looking into the forces, hopefully I'l be able to share that data. If I can prove the market with Kickstarter this will encourage their interest.

The first real nut tool innovation I have seen in my 30 years of climbing - congrats.

Tim Preston wrote: I've been trying to figure out a way to measure and compare the force LittleHammer can produce

That would not make any sense. Your device does not generate a set force, but rather a set energy (the energy stored in the spring when cocked, or the kinetic energy of the moving mass just before it hits the stop).

If you set your device tightly against a rigid hard target (such as a stuck nut), it can generate a very high force for a very short time. If you set it against a softer target, it will generate a lower force for a longer time. In both cases, the amount of ENERGY released is exactly the same.

What you might be able to compare it to is the amount of energy released by someone's hand holding a small rock/large cam and hitting the back of a traditional nut tool. Your device's moving mass is smaller, but its impact velocity is likely higher, so the impulse (again, energy) may be similar.

Eric and Lucie wrote: That would not make any sense. Your device does not generate a set force, but rather a set energy (the energy stored in the spring when cocked, or the kinetic energy of the moving mass just before it hits the stop). If you set your device tightly against a rigid hard target (such as a stuck nut), it can generate a very high force for a very short time. If you set it against a softer target, it will generate a lower force for a longer time. In both cases, the amount of ENERGY released is exactly the same. This is called an impulse in engineering. You cannot measure it as a force. What you might be able to compare it to is the amount of energy released by someone's hand holding a small rock/large cam and hitting the back of a traditional nut tool. Your device's moving mass is smaller, but its impact velocity is likely higher, so the impulse (again, energy) may be similar.

Wow...you must be a blast to hang out with.

Chris Rice wrote:The first real nut tool innovation I have seen in my 30 years of climbing - congrats.

WHAT!?!!? Did you not see the recent penis shaped nut tool??!?

you can use a cam as a hammer to hit a nut tool against a fixed nut.

knowledge is better than gadgets

mpech wrote:you can use a cam as a hammer to hit a nut tool against a fixed nut. knowledge is better than gadgets

Still requires two hands. Sometimes it'd be nice to get them out at difficult stances with one hand.

csproul wrote: Still requires two hands. Sometimes it'd be nice to get them out at difficult stances with one hand.

Is that so that you can preserve your top-rope redpoint send? :)

At least for me, if the nut is so fixed I can't get it out with one hand, I will hang on the rope and deal with the situation.

I can't imagine being at a difficult stance and continuously re-loading a spring-activated tool while working to remove a nut...

mpech wrote:you can use a cam as a hammer to hit a nut tool against a fixed nut. knowledge is better than gadgets

wow thanks for joining us

• my post has been edited to remove the caps-lock, because although I still feel it may have been warranted, it is without a doubt obnoxious to look at

mpech wrote: Is that so that you can preserve your top-rope redpoint send? :) At least for me, if the nut is so fixed I can't get it out with one hand, I will hang on the rope and deal with the situation. I can't imagine being at a difficult stance and continuously re-loading a spring-activated tool while working to remove a nut...

Ya well, when I go free climbing, I try to actually climb; whichever end of the rope I end up on. If I want to hang, I go aid climbing. Or sometimes sport climbing.

csproul wrote: Ya well, when I go free climbing, I try to actually climb; whichever end of the rope I end up on. If I want to hang, I go aid climbing. Or sometimes sport climbing.

I agree with you on this.

If the percussive impact of this device were great enough that I would never have to cam-hammer a nut again, then I agree that this would be a really great invention.

However, my suspicion is that this $50 nut tool will still not obviate the need to cam-hammer nuts out...

That's the $50 question.

mpech wrote: I agree with you on this. If the percussive impact of this device were great enough that I would never have to cam-hammer a nut again, then I agree that this would be a really great invention. However, my suspicion is that this $50 nut tool will still not obviate the need to cam-hammer nuts out...

I don't think this tool or any other will ever completely remove the need to hammer on some nuts, but this seems it might be good for the hundreds of times you now tap out slightly stuck nuts.

Cool idea. Still have questions though. If I had cash under the mattress I'd prob pay for one to see how it worked. However ...

mpech wrote: I agree with you on this. If the percussive impact of this device were great enough that I would never have to cam-hammer a nut again, then I agree that this would be a really great invention. However, my suspicion is that this $50 nut tool will still not obviate the need to cam-hammer nuts out...

At last I'm out of my forum probation post limit and can answer questions; being proved a human feels good.

I haven't used a cam-hammer since I've been climbing with my LittleHammer prototype. Actually it was feeling guilty about using highly engineered cams in such a primal way that lead me to design LittleHammer.

If we get into production the kickstarter budget allows for some media samples so I'll be able to send them out and to get some independent reviews.

Looking good at 73% with 23 days to go.

Hey Tim,

Sign me up for a media sample, man. No one can consistently get a stopper stuck quite as hard as I can.

Tim Preston wrote: I've been trying to figure out a way to measure and compare the force LittleHammer can produce. ... Anyway the company's engineers are looking into the forces, hopefully I'l be able to share that data. If I can prove the market with Kickstarter this will encourage their interest.

That's the kicker for me. Your bounce test is nice, but I'd really like a comparison of which (normal nut tool vs LittleHammer) is more effective at removing a given stuck piece of pro, as that is the crux of the issue. Of course, it would be tricky to test that in a controlled manner (both would need to remove the same nut from the same placement). Measuring the impact in some way is critical to convince me (and others) to purchase a 50-70 dollar nut tool.

Eric and Lucie wrote: That would not make any sense. Your device does not generate a set force, but rather a set energy (the energy stored in the spring when cocked, or the kinetic energy of the moving mass just before it hits the stop). If you set your device tightly against a rigid hard target (such as a stuck nut), it can generate a very high force for a very short time. If you set it against a softer target, it will generate a lower force for a longer time. In both cases, the amount of ENERGY released is exactly the same. What you might be able to compare it to is the amount of energy released by someone's hand holding a small rock/large cam and hitting the back of a traditional nut tool. Your device's moving mass is smaller, but its impact velocity is likely higher, so the impulse (again, energy) may be similar.

OK, I'm going off some basics physics that I learned long ago, but I can't make heads or tails of this. First you say that the device does not generate a "set" force. Then you say that the device can generate a high force for a short time.

Deconstructing this, cocking the spring back transfers energy from the user to the spring. When the spring is released, its potential energy is transferred to the brass weight, causing it to accelerate. This kinetic energy is then transferred to the nut through a relatively inelastic collision. Given the work-energy principle, it is doing work (assuming the nut moves) and the imparted impact does involve force, just as a falling object imparts an impact force on the ground...or so I think. Either way, one could place both Little hammer and a nut tool against a force plate/sensor and measure the impact of LittleHammer vs that of a nut tool being struck with a cam. Or, one could use an accelerometer on the brass weight and the striking cam to calculate which would impart more impact force. Like I said, haven't had physics in a while.

scienceguy288 wrote: OK, I'm going off some basics physics that I learned long ago, but I can't make heads or tails of this. First you say that the device does not generate a "set" force. Then you say that the device can generate a high force for a short time. Deconstructing this, cocking the spring back transfers energy from the user to the spring. When the spring is released, its potential energy is transferred to the brass weight, causing it to accelerate. This kinetic energy is then transferred to the nut through a relatively inelastic collision. Given the work-energy principle, it is doing work (assuming the nut moves) and the imparted impact does involve force, just as a falling object imparts an impact force on the ground...or so I think. Either way, one could place both Little hammer and a nut tool against a force plate/sensor and measure the impact of LittleHammer vs that of a nut tool being struck with a cam. Or, one could use an accelerometer on the brass weight and the striking cam to calculate which would impart more impact force. Like I said, haven't had physics in a while.

yes, you are correct, obviously the nut tool will impart a force, the only thing that Eric and Lucie is saying is that the force is dependent on a lot of different factors which means that you can't just make a blanket statement like "the little hammer imparts 1.2 kN of force to a fixed nut" or something like that. As Eric and Lucie said, the correct way to specify this would be the energy the little hammer is capable of producing which you could then compare to the energy of hitting a nut tool with a cam or rock or whatever.

scienceguy288 wrote:Either way, one could place both Little hammer and a nut tool against a force plate/sensor and measure the impact of LittleHammer vs that of a nut tool being struck with a cam. Or, one could use an accelerometer on the brass weight and the striking cam to calculate which would impart more impact force. Like I said, haven't had physics in a while.

Sure, you could measure a force, but it would not in any way be a characteristic of the tool, but rather a characteristic of the nut placement you are working on.

It's a bit like if you were trying to characterize a hammer by hitting something with it. If you hit a concrete wall, you will generate an incredibly high force even with a tiny hammer, but if you hit a mattress, that force will be many orders of magnitude smaller, even with a sledge hammer (but that force will act for a much longer time... while the mattress undergoes a large deformation).

• Tiny hammer on concrete: low energy, high force, short duration (hard impact)
• big sledge hammer on mattress: high energy, low force, long duration (soft impact).

Does that make more sense?

I think that the value of this tool is that it is likely easier to hold snug against a nut in just the right place and at the right angle, without having to worry about hitting it with a rock of cam, or by hitting the nut with the tool itself. As a result, the energy of the moving mass will be transmitted very efficiently to the nut, and the shock will be very hard, so it will be able to reach a high force (more like the concrete wall than the mattress).