What inventions can solve everyday problems?

  • Thread starter Shay10825
  • Start date
In summary, the conversation was about the idea of a heated butter knife to solve the problem of using hard, refrigerated butter that tears up bread when spreading. The discussion touched on the challenges of creating such a product, including the need to heat the knife quickly without also heating the handle, as well as the marketability of the product. Some alternative solutions, such as using a microwave or holding the knife under hot water, were also mentioned. Ultimately, the conversation highlighted the fact that not all inventions make sense or actually work, but they can still be successful if they sell well.
  • #1
Shay10825
338
0
Hi

I need to come up with an invention. Any ideas? What are some problems you have that can be solved with a simple invintion (it can be complex but not too complex)?

~Thanks
 
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  • #2
I am currently in the need for a time machine. However, there is no rush.
 
  • #3
Shay10825 said:
Hi

I need to come up with an invention. Any ideas? What are some problems you have that can be solved with a simple invintion (it can be complex but not too complex)?

~Thanks

I want a heated butter knife. We don't use butter quickly enough to leave it out, and refrigerated butter tears up the bread.
 
  • #4
Ivan Seeking said:
I want a heated butter knife. We don't use butter quickly enough to leave it out, and refrigerated butter tears up the bread.

As the guys on the Guinness commercial say, "Brilliant" ! <clink> :approve:
 
  • #5
Gokul43201 said:
As the guys on the Guinness commercial say, "Brilliant" ! <clink> :approve:


Brilliant!
 
  • #6
Ivan Seeking said:
I want a heated butter knife. We don't use butter quickly enough to leave it out, and refrigerated butter tears up the bread.

This is why I could never survive in patent law. My mistake is I always wind up thinking about marketability rather than patentability. One of my friends is a patent attorney and sometimes tells me about things that he processes (after the patent is issued so it's no longer confidential). He thinks these things are so cool, and I end up asking how he keeps a straight face when someone describes their invention to him. With something like that, I'd be just sitting there laughing...isn't it easier just to quickly warm the knife under hot water than to find a battery or plug and wait for an electric one to warm up? Then again, 5 seconds in the microwave works for butter too. Then he'll tell me that having an electric knife is so much faster, and I'll say something like, "faster than 5 seconds?" :uhh: I can't imagine why he gets annoyed with me when I start laughing at the stuff he works on.
 
  • #7
Holding the knife under hot water in not ideal. It takes several seconds to warm up, and you don't want to be using a wet knife, so you wipe it down, removing most of the heat that way. Nah !

Putting the butter in the microwave isn't great either. Too little time and you only heat up the surface - but you heat up the entire surface, making it all slippery and messy. Too long, and you've got (b)utter chaos.

But getting a knife (edge) to heat up fast is not easy either. It takes at least a few tens of joules to get the knife warm enough. And with about a 1.2V battery (you can fit a AAA bettery in a knife handle), you want to get at least 4 or 5 watts to heat up the knife quickly. That's the tricky part, I guess.
 
  • #8
Gokul43201 said:
so you wipe it down, removing most of the heat that way. Nah !
:rofl:
Holding the knife under you arm, so it gets to body temperature :rolleyes:
We don't have much money for experimental physics back in France :frown:
 
  • #9
Most inventions are a waste of time [including this one], but, Moonbear, since you wish to discuss the finer point of butterology... First of all, it is not possible to sufficiently soften a slice of butter in the microwave without melting the edges. So the edge effects create inefficiencies that demand a more economical solution. Also, the wasteful microwave solution requires that an additional plate be used for each buttering event. Then the plate much be washed, dried, and restocked. Next, a typical butter knife does not have enough mass to sustain butter homogenity when applied to a system in paneity. Besides, the energy lost in heating pipes and water far exceed even the cost of the butter being used. Clearly these facts alone justify further furnding and research. :tongue2: :tongue:

Really though, it doesn't matter if a product makes sense as long as it sells. It doesn't even matter if the product actually works! :yuck:
 
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  • #10
Wow I really like your idea :smile: ! I have this problem all the time. How would I make such a thing? How would I get the knife to heat?
 
  • #11
Shay10825 said:
Wow I really like your idea :smile: ! I have this problem all the time. How would I make such a thing? How would I get the knife to heat?

More importantly, how do you get the knife to heat without heating the handle too?!
 
  • #12
Ivan Seeking said:
Most inventions are a waste of time [including this one], but, Moonbear, since you wish to discuss the finer point of butterology... First of all, it is not possible to sufficiently soften a slice of butter in the microwave without melting the edges. So the edge effects create inefficiencies that demand a more economical solution. Also, the wasteful microwave solution requires that an additional plate be used for each buttering event. Then the plate much be washed, dried, and restocked. Next, a typical butter knife does not have enough mass to sustain butter homogenity when applied to a system in paneity. Besides, the energy lost in heating pipes and water far exceed even the cost of the butter being used. Clearly these facts alone justify further furnding and research. :tongue2: :tongue:

Really though, it doesn't matter if a product makes sense as long as it sells. It doesn't even matter if the product actually works! :yuck:

Hmmm...but, you don't just put the slice of butter in the microwave, you put the whole stick in. Then, the melted edges ARE the slice. Besides, melted butter is even better to spread on bread than soft butter. Just blot it up with the bread and you don't even need a knife. :approve: And no need for a plate. Butter comes packaged with it's own handy dandy wax paper wrap. Or leave it on a plate in the fridge. :biggrin: Then again, I prefer home-baked bread, and I manage to eat most of it fresh out of the oven while it's still hot, so the bread itself is the solution to softening the butter. The knife naturally warms while slicing the hot bread. :tongue:

:rofl:

This thread keeps making me hungry.

EDIT: Hey, it's been done...well, sort of...not battery-operated, and not intended for butter. There are plug-in heated knives for beekeeping (getting the wax caps off the hives) and for candle-making.

http://www.jonesbee.com/tools.html

http://www.longwyckcandleworks.com/EquipAccess.html

See near the bottom of both pages. Now just make a somewhat lower-temperature battery operated, water-proof and dishwasher safe version, and you'll be rolling in the dough...or at least will have the butter for the dough once it's baked. :rofl:
 
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  • #13
Moonbear said:
More importantly, how do you get the knife to heat without heating the handle too?!

This is not hard at all...no really ! The melting point of butter is just about 34C or 95F.
 
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  • #14
I'd buy it too...
 
  • #15
Moonbear said:
More importantly, how do you get the knife to heat without heating the handle too?!

Could I make it so the blade screws off? How would I make it so the battery heats the blade?

Could I still use this idea even though it has already been invented but not for butter knifes?
 
  • #16
Shay10825 said:

Could I make it so the blade screws off? How would I make it so the battery heats the blade?

Could I still use this idea even though it has already been invented but not for butter knifes?

You could put the knife in a warmer and then remove it to cut the butter.

The Bob (2004 ©)
 
  • #17
The Bob, that's a good idea but i want the knife to warm itself.

Hears what I was thinking about.
The batteries would go in the handle and the blade would screw into the handle (so you can wash the blade). But I don't know how exactly I would build this (I've never built anything that runs by battery). What would I need to but to make this? Any ideas?
 
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  • #18
Gokul43201 said:
This is not hard at all...no really ! The melting point of butter is just about 34C or 95F.
See : Gokul backups the sudation process for heating the knife because he likes salted butter too :tongue2:
 
  • #19
Shay10825 said:
The Bob, that's a good idea but i want the knife to warm itself.

Thanks. I try.

Shay10825 said:
Hears what I was thinking about.
The batteries would go in the handle and the blade would screw into the handle (so you can wash the blade). But I don't know how exactly I would build this (I've never built anything that runs by battery). What would I need to but to make this? Any ideas?

Yes. Make an electromagnetic. The blade can be the metal to magnetise and that should create heat, IIRC.

The Bob (2004 ©)
 
  • #20
I went on a site that said how to make an electromagnetic and in one of the steps it said:
"Neatly wrap the wire around the nail. The more wire you wrap around the nail, the stronger your electromagnet will be. Make certain that you leave enough of the wire unwound so that you can attach the battery."

Would I have to wrap the blade in a wire? I can't cut butter with a blade that has wire wrapped around it? How do I make an electromagnetic without wrapping wire around the blade?
 
  • #21
Shay10825 said:
Would I have to wrap the blade in a wire? I can't cut butter with a blade that has wire wrapped around it? How do I make an electromagnetic without wrapping wire around the blade?

I was thinking of having the current go through the blade and then through an electromagnet. Might work. I will think of another idea and see if it is better.

The Bob (2004 ©)

P.S. How long can you wait?
 
  • #22
This is for the Science Fair that has to be submitted by October 15.

~Thanks
 
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  • #23
Shay10825 said:
This is for a Science Project that has to be submitted by October 15.

~Thanks

So it has to be finished by the 15 October? Oh dear.

The Bob (2004 ©)
 
  • #24
I know I just found out that the deadline was so soon because school just started, and I'm required to go to the school science fair :frown: .
 
  • #25
Moonbear said:
Hmmm...but, you don't just put the slice of butter in the microwave, you put the whole stick in. Then, the melted edges ARE the slice.

Really this is dangerous if you don't use all of the butter immediately. Diary products should be kept at < = 55 degrees until ready for use. So heating the entire stick and putting back in the fridge creates opportunities for food poisoning.

An interesting fact from the National Centers for Disease Control:
~80% of all cases thought to be influenza is actually minor food poisoning.
 
  • #26
Shay10825 said:
I went on a site that said how to make an electromagnetic and in one of the steps it said:
"Neatly wrap the wire around the nail. The more wire you wrap around the nail, the stronger your electromagnet will be. Make certain that you leave enough of the wire unwound so that you can attach the battery."

Would I have to wrap the blade in a wire? I can't cut butter with a blade that has wire wrapped around it? How do I make an electromagnetic without wrapping wire around the blade?

You would need resistor [Ni-Cd] wire like that used for heaters. Magnetism is actually not a good heat producer in most cases. You need resistance and current flow through that resistance. You might be able to steal some wire from an old space heater. The actual resistance would be very important and a little understanding of ohms law, and electricity in general, would be quite helpful. Some experimentation is definitely in order.

I would imagine that any patents for something like this have already expired, so I think you are safe to modify an existing device. Also, change the device by 10% and the patent no longer applies.

I'm glad you like the idea. :smile:
 
  • #27
Is there any other way to heat the blade?
 
  • #28
Not that I can think of. You can create heat with electrical resistance and current flow, friction, or with a chemical reaction. Maybe a special knife with a warmer would work as suggested earlier. Still, heater wire is not difficult to come by. This is the most sensible approach to direct heating and everything from old toasters, to hair dryers, to space heaters [and bee wax cutters] use the stuff. By changing the length of the wire you can control the heat produced.

Again though, a separate knife warmer still might work. Maybe you could even use something microwaveable.
 
  • #29
Do you know of any websites or the types of books I would look into figure out how to do this (would I just get books on electricity)?
 
  • #30
I've got to go right now but maybe someone else can help you with some links. You only need to get a few concepts straight to proceed; good stuff too!

Ohm's Law
Heat from electricity

I'll be back later.
 
  • #31
The first thing to do is assess feasibility :

Can you deliver enough power to heat a knife edge by at least 10C (18F) in not too long a time ? What kind of resistance wire would you use (Ni-Cr, nichrome wire/ribbon ?) and what aspect ratio is required to get the right resistance ? Is it possible to get the required resistance out of a wire that can be embedded in a (~ 2 or 3 mm thick) blade ?


Here are a few design aspects to keep in mind :

You need a thermally conductive, yet electrically insulating thermal short between the resistor and the knife edge. Mica or silicone rubber might work for this.

The knife edge itself needs to be a moderate thermal conductor (to transfer heat from its inside surface to the outside) with a low heat capacity. The right material needs to be picked that match these criteria...this part is not too hard.

The rest of the knife, especially the neighbouring material to the knife edge, must be a good thermal insulator...and be reasonably (not especially, but fairly) strong if you're using it in the blade. A high density plastic could work. Or you might just be able to get away with an all stainless steel blade - but you have to do the calculations to make sure.

The blade design, I think may be the hardest part. The resistance wire (part of the circuit) needs to be inside the blade, near the knife-edge. To do this, I would think the blade itself will need to be made in 2 or more pieces that get welded or brazed (or joined some way) together. If the knife edge is a different material than the rest of the blade, that's an additional step of work. This however, is only a detail, and can be solved.

For the handle, I think a high density plastic will work fine. These are pretty strong, yet very easy to machine.

I think I've made several assumptions (about your level, capability, access to machining tools, etc) before starting this post. Maybe I should have checked first...
 
  • #32

I am in 10th grade but I am taking AP Physics, AP Calc and other AP classes. I don't have any experience with electricity and heat.
Will I be able to get any of these materials at a Home Depot or other local store or will I have to order them online?
 
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  • #33
Shay10825 said:

I am in 10th grade but I am taking AP Physics, AP Calc and other AP classes. I don't have any experience with electricity and heat.
Will I be able to get any of these materials at a Home Depot or other local store or will I have to order them online?

Okay, how about for the handle, rather than machining plastic, maybe you could modify a small flashlight...just use the handle of it, since that's already made to fit batteries (once we work out what size batteries you'll need to get enough heat for the blade, you can choose an appropriately sized battery). I'm not sure what type of plastic those use though, so need to check they won't just melt.

I like your idea of being able to disconnect the blade from the battery compartment to wash the blade. I would also suggest including an o-ring on the threaded part between the handle and blade to make it a bit more waterproof during use (the o-rings you'll find in the plumbing section of any hardware store).

Toaster wire...you probably can get it at a hardware store...Radio Shack is the other fun place to shop for electrical/electronic components, but might also be able to find old toasters at garage sales or in the trash. Ask around, you may have some relatives with some old toaster in the basement that someone always meant to fix and never did.

Of course you don't really want it to get as hot as a toaster, or you'll just melt your butter rather than cut it, and likely burn your hands or start a fire. You'd want an on/off switch too.

I can't help much with how to make that work...I know of the electromagnet around a nail trick, but that's not useful for your purpose (I used one of those for a 6th grade science fair project...made a simple alarm for a door...I don't recall anyone making anything that heated).
 
  • #34
Ivan Seeking said:
Really this is dangerous if you don't use all of the butter immediately. Diary products should be kept at < = 55 degrees until ready for use. So heating the entire stick and putting back in the fridge creates opportunities for food poisoning.

An interesting fact from the National Centers for Disease Control:
~80% of all cases thought to be influenza is actually minor food poisoning.

But if you expose yourself to those pathogens from early childhood, you build up an immunity. :rofl: :bugeye: Shouldn't the microwaves kill the germs? What type of radiation do they use to kill germs on irradiated food? Of course, storing it for about 30-45 min at 350 degrees F prior to use, preferably mixed with chocolate, flour, eggs, and baking powder, also works. :tongue2:

Don't worry, I don't actually do this (the microwaving thing), I was just giving you a hard time for nearly sending my parents to visit me (thankfully Ivan swerved away from them, so they stayed in FL where they belong!). :biggrin:
 
  • #35
Gokul43201 said:
Can you deliver enough power to heat a knife edge by at least 10C (18F) in not too long a time ? What kind of resistance wire would you use (Ni-Cr, nichrome wire/ribbon ?) and what aspect ratio is required to get the right resistance ? Is it possible to get the required resistance out of a wire that can be embedded in a (~ 2 or 3 mm thick) blade ?


. . . but you have to do the calculations to make sure.

How can I find this? Is there a formula or something that I am suppose to use?
 

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