You are viewing bramcohen

Mon, Jun. 18th, 2007, 02:26 pm
Cutlery

Why does the fork have four tines? The Evolution of Useful Things has an explanation of how the fork came to be, but not a coherent explanation as to why the number stopped at four. More tines would clearly be better, because it would require less force to skewer food and hold it in place better. It appears to be an engineering limitation - tines are very thin, and you don't want them to bend excessively.

Can modern materials do better? The strength of a tine is proportional to the fourth power of its width, so the strength of a tine on a fork with five tines instead of four needs to be about (5/4)^4 ~~ 2.5 times as strong as a regular tine. My rather sketchy research indicates that titanium ought to be able to handle that, and in fact the tines on a titanium fork I got are about the right width for five to fit. To get to six tines, they need to be about 5 times as strong as with four, which might be a bit much, although a material such as tungsten, corundum, or tungsten carbide might do the trick.

I decided, given the above calculations, to try other materials of cutlery. My other reason for trying other materials is that I find metallic tastes overwhelming, and wanted to see if any of them don't interfere with my enjoyment of food.

The two types of cutlery I tried are titanium and lexan. Both of these seem to be intended primarily for camping, and so are designed to emphasize their light weight than their other desirable properties.

Titanium I found unfortunately to have a slight metallic taste. Less than stainless steel, and much less than aluminum, but still there. Also, titanium cutlery being designed for light weight while camping tends to be rather small. It does have the nice small tines, which could be used to give it five tines but isn't. I think if there were titanium cutlery which was made to the size and appearance of regular table cutlery, but with five tines instead of four, it would be quite nice.

Lexan I'm rather fond of. After having it in my kitchen for a while I find I always instinctively reach for a spoon or fork made of lexan, particularly the spoons, because of the amount of contact between one's tongue and the spoon when eating soup or cereal. In fact, I've noticed that when using metal cutlery I always hold my tongue back while biting in a weird and awkward way to try to avoid the taste of metal, but I don't do that using lexan, which makes the food eating process much more enjoyable. It also has very low thermal conductivity, which is very nice when eating soup or ice cream, although it is possible to heat lexan enough to melt it, so you can't use it like a spatula. The lexan knife is somewhat pointless though - it isn't very strong, and knives don't generally come in contact with your mouth anyway, so there isn't much of a taste issue. There's unfortunately an aesthetic limitation of lexan cutlery as well. It looks plastic and disposable, which it most certainly is not. I don't know if that's a result of the strength and production engineering needs of making lexan cutlery, or simply poor design.

With currently used materials, I think what I'd really like is a cutlery where the forks and spoons had lexan ends, for taste and low thermal conductivity, and metal handles, for strength, and the knife was an ordinary metal knife.

Possible new materials, and I'm completely speculating here, are tungsten, corundum, and tungsten carbide. Tungsten would probably be a lot like titanium only more so, and rather heavy. Corundum and tungsten carbide would probably score very well in terms of both flavor and strength, and it would be amusing to have cutlery made of sapphire, although cost might be an issue. Or not. The cost of both of those materials has plummeted recently, and cutlery used to be something which held a significant fraction of peoples's savings, while these days a set is considered expensive if it costs much more than dinner at a fancy restaurant. For items used every day for decades, a budget of several thousand dollars seems not unreasonable. People certainly are willing to spend bizarrely large amounts of money on wedding and engagement rings.

When I bring up the subject of cutlery and my observations it has an odd effect on people. They seem to get a desperate need to find some other subject to talk about, or go feed their cat. Very strange considering how fascinating the subject matter is.

Mon, Jun. 18th, 2007 10:04 pm (UTC)
wisedonkey

I can certainly understand your frustrations with metallic dinnerware. Several times in recent history I've unwittingly created a battery in my mouth while eating. A cheaper solution would be a non-reactive coating applied to existing metals.

Mon, Jun. 18th, 2007 10:16 pm (UTC)
jonathankorman

Hmmnn. Lexan can be dyed to any colour, I think, which suggests some interesting æsthetic possibilities.

On the other hand, I'm not convinced that more tines would really be an improvement. The tines would of course have to be narrower, which it seems might interfere with the fork's food-platform function.

Tue, Jun. 19th, 2007 02:43 pm (UTC)
bramcohen

With five tines each of which is 4/5 the width of a four-tined version, the area of the tines would be exactly the same, with narrower gaps, so it would be a strictly superior pea-scooper, in addition to a very superior meat-spearer.

Tue, Jun. 19th, 2007 04:03 pm (UTC)
jonathankorman

A friend suggests that more tines would require more force to penetrate food, like a fakir on a bed of nails.

I demand experimental verfication of these suppositions!

Mon, Jun. 18th, 2007 10:23 pm (UTC)
jered

What about ceramics?

Mon, Jun. 18th, 2007 11:31 pm (UTC)
chouyu_31

I suspect that ceramic utensils would tend to break if you dropped them (like ceramic dishes).

Thu, Jun. 28th, 2007 08:25 am (UTC)
kragen

There are ceramics and then there are ceramics. I didn't read the earlier suggestion as a suggestion to make cutlery out of fired clay that fills with cracks as the water boils out in the kiln, but as a suggestion to use high-strength ceramics.

Thu, Jun. 28th, 2007 03:14 pm (UTC)
chouyu_31

Right, but even higher strength ceramic dishes (chinet) can and do break when dropped, though it is more difficult. But even if you had a fork made out of the hardest ceramics available, it could *still* be prone to shattering (for the same reasons why tempered steel can also be shattered).

Thu, Jun. 28th, 2007 11:44 pm (UTC)
kragen

It's true that ceramics tend to be very hard and fail by breaking rather than by plastic deformation, but some are hardly more prone to shattering than tempered steel.

Harder materials (if by "harder" you mean "higher Young's modulus") are more prone to shattering, not less, if you hold tensile strength constant.

Mon, Jun. 18th, 2007 10:57 pm (UTC)
4zumanga

I've thought about more prongs.. but could you have a problem with it becoming too much like a cutting implement, chopping through food rather than picking it up?

Tue, Jun. 19th, 2007 02:45 pm (UTC)
bramcohen

Nah, this number of prongs only gets it down to the size of a fine-toothed comb, anything close to a knife edge in terms of edge width would simply break. The cross sectional areas do drop a lot, but that's by design, to make it better able to spear meat, and nowhere near small enough to make it able to spear living flesh.

Wed, Jun. 20th, 2007 09:30 pm (UTC)
landley

Some friends of mine gave us some of these as a wedding present:

http://www.splayds.com/

And they are amazingly cool. (It's a stainless steel metal SPORK. With straight edges on the sides so you can spread with 'em too. You still need a steak knife, and trying to get the last few sphagetti-os out of a can with the tip of one is an exercise in frustration, but other than that they're highly cool.)

Alas, still metal.

Mon, Jun. 18th, 2007 11:07 pm (UTC)
glessard: Redox

The taste of metals is a redox issue. Use silverware -- silver-plated silverware. It tastes less, as has been known for a long time (see early chapters of "Les Misérables" for a discussion.) For the same chemical reason, they used to use silver plating on hip-replacement implants for durability.

No dishwasher, though. You gotta pick your poison.

Tue, Jun. 19th, 2007 02:47 pm (UTC)
bramcohen: Re: Redox

Can you point to a web site explaining the issue, or at least the relative amounts which different materials will cause 'redox'? The web sites I find on simple searching discuss fire more than metal surfaces.

Tue, Jun. 19th, 2007 07:04 pm (UTC)
glessard: Re: Redox

I should have said oxidation potential (or its reverse, reduction potential http://en.wikipedia.org/wiki/Redox_potential.) In any event, metals that are more oxidizable tend to produce a small amount of charge transfer between your tongue and themselves. I think that it's the acidity from your saliva that oxidizes a small amount of the metal. A more extreme version of this effect can be had by licking the electrodes of a 9V battery... it is definitely tasty. Now, I don't really know the chemistry and it is undoubtedly not as straightforward as I think it is. I'm sure there is literature on this and related topics; I found this recent paper, whose citation list might be a good starting point: http://chemse.oxfordjournals.org/cgi/content/abstract/bji014v1

If you look at a table of reduction potentials such as http://en.wikipedia.org/wiki/Table_of_standard_electrode_potentials, you can see that reduction to gold has the highest potential, which conversely means that it resists oxidation more readily. Coincidentally or not, gold is actually reputed for being tasteless (to the tongue.) Getting gold plating redone on your silverware every couple years might get old, though.

Tue, Jun. 19th, 2007 08:55 pm (UTC)
bramcohen: Re: Redox

That can't be the whole story, because titanium has much less metallic taste than aluminum, but very similar potential.

Interestingly, everything says that titinium has no taste, while to me it just have very little taste. Maybe I'm especially sensitive.

Tue, Jun. 19th, 2007 09:14 pm (UTC)
glessard: Re: Redox

I'm pretty sure that the forks you want would be made of gold-plated titanium.

Thu, Jun. 28th, 2007 03:08 pm (UTC)
chouyu_31: Re: Redox

The trick with titanium, generally, is that the moment titanium is exposed to oxygen, it oxidizes. But this oxidized layer is quite strong (I believe on par with the base titanium), and even when scratched (down to the base titanium), oxidizes more or less instantly. This (among other things) is why titanium is being used for building exteriors (the first hit for 'titanium building' at google talks about this).

What I suspect is that you may be tasting the reverse of this reaction: Ti2O3(s) + 2H+ + 2e- -> 2TiO(s) + H2O .

Wed, Nov. 7th, 2007 05:29 am (UTC)
(Anonymous): Re: Redox

Of course you are more sensitive. This Aspie hates any metals and yes, Titanium has a taste. Of course Aluminum is worse. I agree that 5 tines would improve the ability to scoop peas. Of course my significant other would love a 5 tined fork because he has this habit of eating ice cream with a fork and would love the improved ability to keep the sloppy melting stuff off his keyboard (of course using a spoon would accomplish this nicely but being the Aspie he is creates a dilemma in getting him to change any ingrained habit). Consider this 5 votes for a five tined fork from 3 Aspies and 2 Kanner Cuties who all think this is a great idea. Good Job Bram Bit Torrent and Five Tined Forks!

Mon, Jun. 18th, 2007 11:10 pm (UTC)
steeltoe

It's called a FORK not a threek of fivek.

The real answer is that you should get some real actual siverware, which shuld be more inert than steel.

Flatware is made from steel because it is easy and cheap to tool.

Tue, Jun. 19th, 2007 03:09 pm (UTC)
bramcohen

Got a link to a chart of how 'inert' various metals are?

Tue, Jun. 19th, 2007 03:13 pm (UTC)
steeltoe

No - my only evidence is my tongue.
(Deleted comment)

Tue, Jun. 19th, 2007 12:50 am (UTC)
shmivejournal: Re: Come on

Mom, is that you?

Tue, Jun. 19th, 2007 12:07 pm (UTC)
jered: Re: Come on

If you can't be content optimizing the everyday trivial things that engage and infuriate you the most, how can you tackle the "big" problems? Arguably the French obsession with sauces has done more for the world than nuclear fusion, at least so far.

Tue, Jun. 19th, 2007 02:35 am (UTC)
bitjuggler: What about shape?

Re: Strength, What about modifying the shape of the tines? If they were crimped lengthwise into essentially small angle-iron, would they be stronger?

Re: Taste, The silver thing is interesting, I wonder how a teflon coating (as used on the inside of non-stick pans) would affect the taste and durability. Not to mention ease of cleaning up :) Scrubbing dried food from between tines can be difficult at times...

Tue, Jun. 19th, 2007 05:25 am (UTC)
nangus: Re: What about shape?

Hate creating an account to leave a small comment...

I have a couple of ideas to make improvements.

idea 1: What about making one of the side tongs thinker so that people would still be able to cut food with it.

idea 2: Make the other tongs thin and serpentine so that people would easily be able to spear and hold food.

idea 3: I was also thinking about the way that arrows work so that they will go in easily. Some one could add a small rounded barb such that it is easier to push in then to pull out. The idea would be that it would prevent the food from falling off, and still be able to be pulled off using the teeth

P.S. I tend to forget where and when I comment.

idea 4: Sharpen the side so that one could actually put food with a plastic fork. If you are like me then you would like to see people injured then sharpen it a lot :) Might me a good idea to just the fork enough so the it can cut not bludgeon your food into pieces.

idea 5: use a steak knife to eat. This is my personal choice. One might dismiss this out of turn. If one thinks for a sec then they will realize that a steak knife has all of the properties of an ideal fork.

Case for using a steak knife:
Sharp point makes it easy to spear food. It is a strong implement, does not bend or break. Little metallic taste there is not actual contact with mouth serf ices the food contains all of the implement. serrated edge holds food in place. Easy to clean, there is not really anything for the food to get stuck between.

Case against using a steak knife:
You look feral, might scare friends and family (this might be a point for I can not decide). If your Knives are very sharp you might hurt your self (might also be a case for. Thin the heard and all that). People tend to have fewer steak knives then forks, meaning that one will run out fast. A little hard to eat some foods until one grows accustomed to using it (kinda like chop sticks).

Tue, Jun. 19th, 2007 03:12 pm (UTC)
bramcohen: Re: What about shape?

Teflon has a tendency to scrape and flake off over time if touched by anything hard, like, say, teeth.

Changing the shape to be slightly rectangular rather than square could produce a dramatic increase in tine strength, since the fourth power I mentioned is the cube of one direction times linear on the other. However, sideways forces are also applied, and I think the strongest forces applied are when spearing, and circular is the strongest shape for preventing bending on those.

Tue, Jun. 19th, 2007 02:50 am (UTC)
eldereft

Have you considered diamond coating? Not that it would be even remotely economically feasible (though it is getting close to cheap on a research scale), but I know for a fact that we can get good adhesion on titanium, and it sure is pretty. After polishing, of course - there tends to be a bit of graphitic phase on the outside as-grown, and depending on the growth chemistry the crystal tends to grow like extruding a cube point-first from the substrate rather than as layers of planes.

Tue, Jun. 19th, 2007 03:14 pm (UTC)
bramcohen

That might work well, and will likely eventually be cheap, but it has the problems you mentiond, plus diamond is a very good thermal conductor, to the point of being icy to the touch, so eating ice cream with it would be quite unpleasant.

Fri, Jun. 22nd, 2007 04:20 am (UTC)
slayemin

I think four tines is actually a pretty good number for a fork. If you start going overboard with the number of tines, then it may become bigger then your mouth and start to become less optimized for eating with minimum effort. If you wanted to add more tines and take into account bite size, you'd have to move the tines closer together and make them thinner. The thinner the tine, the more dangerous it could be -- It could potentially pierce your mouth like a needle.
Another option would be to have two layers of four tines to make a total of eight tines. That would give you maximized gripping power over your food and it would still be bite sized and non-dangerous. The only problem is the fork is often used in the same way a spoon is used: to scoop up foods. The second layer would become an inconvenient obstacle.
I'd say four tines of decent size is a pretty good solution. If you want gripping power, you could angle the tines in opposite directions like a "V" shape or "^" shape. That would prevent food from sliding off the tines. Some meat forks and pickle forks have this angle to their tines to keep the food from falling off after its been skewered. And, some larger forks are designed so that the tines actually spread apart as you skewer food which gives it a better gripping action. I have such a fork in my cutlery collection if you're interested... I can take a picture.

Mon, Jun. 25th, 2007 08:06 pm (UTC)
arinehoc: Spoons which don't alter taste

Because metal spoons alter taste they are not used for caviar. Caviar spoons are made of bone, are very smooth and are smaller than those in common use. They do not alter taste and have a very nice mouth feel. I can attest that they don't break when you drop them.

Thu, Jun. 28th, 2007 06:33 pm (UTC)
geotramp: Caution...

I would suggest reviewing the new materials for toxicity... I couldn't find the article on the Russian sniper who died immediately from drinking vodka through his tungsten lined barrel but I found:

Acute tungsten poisoning: Much of the information on human toxicity comes from case reports of a purported acute toxic reaction to tungsten dissolved in alcoholic drinks following a tradition of French army artillery recruits drinking wine/beer which has rinsed a recently fired gun barrel.

Fri, Jul. 13th, 2007 05:51 am (UTC)
bramcohen: Re: Caution...

That's really surprising, given how generally inert tungsten is. Then again, so is rhodium, but that doesn't stop it from being highly toxic.
(Deleted comment)

Fri, Jul. 13th, 2007 05:49 am (UTC)
bramcohen: Re: Some idea

No thanks, there's already too much bureaucracy involved in the patent system as it is, and what we need now are politically practical strategies, not abstract pontification.

Sat, Jul. 14th, 2007 03:58 am (UTC)
amarking: Re: Some idea

Amen to that! My patent, which issued in January took me 3-1/2 years and well over 20k in legal and PTO fees, not to mention countless mind numbing hours spent reading 600+ page patents....bleh. While this may be of little concern to large companies with house legal departments and money to burn, as an individual inventor, the process is daunting to say the least.

Wed, Jul. 11th, 2007 05:55 pm (UTC)
amarking

As far as taste is concerned, have you tried higher quality silverware? Specifically 18/8 or 18/10 stainless which contain 8 and 10% Nickel respectively in addition to their 18% Chromium content. The Chromium forms a passivation layer of Chromium Oxide which is water, and for that matter spit-proof. The higher quality stainless steels tend to have far fewer impurities which can also lead to metallic tastes.

As far as tine count, maybe the answer lies in the shape of the tines themselves rather than in numbers? It stands to reason that with more tines, they would need to be thinner since we still need to be able to fit this device into a human head at some point. More thin tines wouldn't really help you hold food better as far as a spearing action since their surface area would remain more or less comparable to a 4 tine design.

How about a design where each tine begins at a point, then widens slightly when viewed in plan, then tapers back down, effectively making each tine into a mini spear (mind you no sharp enough to impale yourself with). This would do two things for you:

In a spearing event, say stabbing some unsuspecting foodstuff, the tines would concentrate the force of the stab into only 4 point loads. This would give you the start you need, wherein the "shoulders" of the tines could be easily be driven into the food to hold it firmly.

In a scooping event - scraping up some lovely sauce that accompanies said unsuspecting foodstuff, the shoulders of the tines would serve to make the spaces between tines narrower, allowing you to support lower viscosity sauces.

For what its worth...

Fri, Jul. 13th, 2007 05:47 am (UTC)
bramcohen

The proper shape for maximizing strength while reducing cross section is to have a cross section in the shape of a plus (I-Beams work on the same general principle). That tends to get gunk stuck in it though, and increases width, which there isn't much room for on a fork's design. (Technically, a hollow cylinder works better, but that's yet even worse for gunk.)

I don't think I've ever tried high quality silverware. The metal content isn't usually labelled in a clear manner.

Fri, Jul. 13th, 2007 05:06 pm (UTC)
amarking

While yes, an H or I beam with a reasonable web depth (the height of the vertical element in the case of an "I" beam) will give you an optimal loading capacity, I dare say that anything that will fit into a human head is far too light to deflect normal stainless steel fork tines.

If you were looking to use lighter, more bendable materials, how about a triangular section tine? Flat on top, with the point of the triangle on the backside of the fork. You'd get web depth without the nooks and crannies. The weight of the infill should be minimal.

Considering the overall performance of stainless as a material, load bearing in a plain old fork really isn't a problem in most commonly available shapes and sizes.

As far as materials composition for silverware being well disclosed, anyone selling even marginally higher end cutlery will show the material prominently as it's a selling point. Here's an arbitrary link I dug up, click on any of the manufacturers or their patterns, and the material is disclosed at the top of the page:

http://www.westernsilver.com/stainless.html

With a service life of 25 years or more, even spending $100 or more on service for 8 is a bargain once you amortize the cost.

Food that doesn't taste like fork....Priceless.

Fri, Jul. 20th, 2007 10:13 pm (UTC)
realbbearbonez

I thought you only used three prongs and even then not to eat ;-)
apology's for the comments :-/

Wed, Jul. 30th, 2008 04:34 pm (UTC)
penangrain

I found this entry while searching on oxides of titanium. I've become concerned about metals toxicity and am looking for alternatives. I know that most plastics, Lexan - type 7, especially are hormone disruptors, and found recently that stainless leached its toxic alloys in combinations of salt and acid (eaten by me in almost every meal), but I had heard that titanium was stable. The first thing that came to mind on hearing this was, "What about titanium dioxide, put into almost all personal care products and known/thought to be a carcinogen?" No metal is really more used than as utensils/cookware. From what I read today titanium does readily oxidize and as titanium dioxide. This leaves me with what I think is the best choice, polystyrene utensils. Yes, flimsy and environmentally damaging, but not a hormone disruptor. Hope I made my point, since I've gotten lost after saying all this. I am after all severely metals poisoned! ;-) Sorry, if not.

But now I have another puzzle. Titanium oxidizes as TiO2, but the titanium dioxide in personal care products comes from iletium(???), not titanium at all. I wonder if there is a difference in toxicity, there probably should be.