Making a handle from a casting of a hand

[rockstar.esq]

So I'm fairly new at blacksmithing and I've been thinking about all the intricacies of what makes a grip feel perfect. I'm curious if anyone has ever developed a technique for making a handle based off of a casting of the users hand?

Thanks in advance for any help!

[Rich Hale]

I have never seen one, you could possible be the first!
One thing I do a lot is to look at and if possible handle any knife that looks like I might like it. I commit to memory what it is I like about the feel and looks. Particularly if the material feels really good to me. There is a large knife show in Denver once a year and that would be a good thing for you to attend. Gun shows are also a place to look around.
My fitst choice is a knife show as most of the time the makers aere there and if you tell them you are a new maker chances are good they may offer some thoughts that may help you.

[Dave Budd]

I've seen a few hobby makers make a polymorph moulding of their grip (basically they stick the tang ina lump of fimo, miliput, etc then grasp it in their hand and cure the clay) They always look a bit rubbish aesthetically and you are of course limited to the knife only feeling any good in one position. Also most of the materials available are fairly brittle, unless you take a casting from your mould in something like a hard fubber or plastic

though it's worth a go for the sheer heck of it I guess ;)

[Robert Mayo]

Yes it has been done there was an artical in one of the knife magazines i think it was Blade a few years back about using playdo to get the exact shape of a customers hand.
But it would have to be the intended buyer for it to fit.

Bob

[Talon Tex Overland]

what kind of rubber are mouthguards made of? if you could get a small block of that stuff couldn't you boil it and then squeeze it to fit your hand the way you do when u fit a mouthguard for kickboxing.

[ThomasPowers]

I've seen it done by gripping warmed wax and then using lost wax casting to do it in Al.

Not very useful as you hand changes it's grip in use and the cast grip is only perfect for *1* form.

[rockstar.esq]

Thanks for all the replies! Lost wax casting might be a good idea. I know there's a type of duplicating machine used for copying rifle stocks with a router. I would suspect the stylus could follow the profile of clay or something just as well as wood. The points about it only fitting one way are insightful. I wonder if the client grasped say three clay handles each in a different way if a person could put a blank in the stock duplicator and use each handle in turn and see what was left. No matter what it would be almost guaranteed to look unattractive. Definitely need to do some experimenting.

[keykeeper]

Heck of an idea, but the man upstairs made hands adaptable to different grips and positions for a reason. The human body is THE best thought out "machine" known.

That said, I would experiment with different knife handles sculpted to fit many hands of many different sizes. To fit a wider range of hand sizes, if you will.

Your product will sell better, and you will be known as a maker of comfortable-handled knives. I see a lot of knives with the handle sculpted or cut with a groove for the forefinger, and a gentle swell for the rest of the fingers and palm. Probably one of the better handle designs used, IMO.

[mcraigl]

To add to Keykeeper's final comments. You COULD use the mold to determine the curvature/radiuses of a palm swell to perfectly fit a customer's hand. I have a rifle that has a palm swell that was carved to fit my hand, and it sure does feel better than a plain jane stock.

[rockstar.esq]

mcraigl, I've heard of an outfit called Herrets that makes hardwood handgun stocks that are custom made based on a tracing of the customers hand. I haven't the slightest idea how they know how to interpret the tracing but I can kind of see myself test fitting a handle against a casting to ensure the customer will be happy.

Keykeeper, you're absolutely right that a more generic profile would sell better but I'm thinking more about the commission project where the concern is strictly fitting that one person perfectly.

On a related note I'm frequently impressed at how chef knife handles aren't entirely well shaped. When grasped like a hunting knife or a machete they fit fine however chef's choke up on the bolster where they frequently get callouses from abrading their finger against the back of the blade.

[keykeeper]

I understand the reasoning of wanting to fit a handle to a persons hand perfectly. However, the comfort/secureness of that grip will be compromised through any range of active motion. The fingers adapt to grip based on the range of motion.

Let's pretend a little:

Hold a 12" bar of 3/4" round by the end in your hand like a knife/sword/etc. Gripping it with the "tip" straight up, sweep it forward, backward, and side to side. Take note of the fingers either loosening or tightening depending on the motion made. Also, watch the wrist.

Do you think a cast handle based on one position of the hand will be as safe, comfortable, or steady as say, a generic shape? The swells and grooves of a cast grip/handle will tend to be bothersome, in my opinion.

Unless someone wants a knife made like that, purely to hang up and look at to say they have one fit "perfectly" to their hand. In that case, I say go for it.

But it will be a bear to use in real world situations.

-As for the chef's knife observation, I think that the basic design is a compromise, also. Chef's knives do such a wide range of tasks that they design them to be used comfortably over a longer period of time. The main feature is the blades wedge shaped profile. I've seen them used for many things in the kitchen, from slicing, dicing, crushing, scraping, even pounding meat by holding the blade and using the handle as a "head" of sorts. Chef's tend to have one single favorite knife, but few will stick exclusively to that one knife for everything.

Edited October 23, 2009 by keykeeper

[chuckster2.0]

Like key keeper said, the hand does different stuff depending on the job. I think determining the best shape would be a better idea. Take your favorite knife and assign different jobs to it and be mindful of how your grip feels on the handle. Though, doing that will change your grip now that your consciously thinking about it. If you want to get really crazy you could use a tactilus pressure mapping pad to map the pressure on a tubular handle and then shave off material to reduce pressure until you have come up with a shape that can do multiple jobs with the least pressure associated with it. That will probably never happen when it comes to guys like us who have limited means but it would be really cool if someone did.

[rockstar.esq]

Chukster and Keykeeper, you're both making lots of sense. When I consider that the knife has only been around for a few thousand years it's more than a little likely that folks have addressed this before. Looking back on handles that fit versus ones that were just ok it's not all that large a dimensional difference. I was hoping that somewhere along the line an approach not entirely unlike fitting a suit, or having a gunstock fitted, there was a technique developed to reliably quantify what needed to be done to make the final perfect work like an extension of the client.

Thanks for offering your insights.

[keykeeper]

Not trying to bring down the idea, just noting my observations and thoughts on the subject.

As far as making the knife an extension of the client, the only way to achieve that is to find out in advance what exactly the client wants, and make it for them. I do not know if anyone has ever created the perfect knife. That is what makes every knifemaker an individual, and what makes some in more demand than others. They know what the client wants, and have the vision and creativity to make it for them.

Good luck in your pursuit, and we want to see pictures of your finished work. Just from these discussions and questions, I think you have a future in what you are wanting to do, and will excel in the craft.

[rockstar.esq]

Keykeeper, thanks for the kind words. I'll post pictures when I've got something put together!

[David Einhorn]

A Sai with a blade (one of my books has a photograph of one) has its own considerations, that would be in common with other long knives used in a similar manner. With the person's hand pointing up, and the guard resting in the hand's web, between the thumb and the first finger, the blade should extend about 1" past the person's elbow (depending on personal preference). The guard needs to be sized so that the person's hand can easily pass through the area between the point on the guard and the blade (with that area of the blade not sharpened). I could be wrong, but the ultimate solution for a bladed-sai would seem to be a selection of sai with differing width guards that a person could try out to see which feels the best for that person. Other considerations are that sai should be made in sets of at least 3 sai, not 2, and they should be weighted for throwing.

A few things I discovered in my wayward youth. :D

[Haasum]

I actually have a knife that has a molded handle. It is cheaply made, both the knife itself and the handle, and it isn't custom made to my hand, but it isn't terrible. It is only bothersome if I hold it "improperly" by which I mean not the way the handle is molded, but there is one section, on my index finger which is very uncomfortable. Of course like I said, it isn't custom made to fit my hand, and it very cheaply made, I bought it for about $2 equivalent American, in Brasil.

I imagine it could work, but I wouldn't want it for anything I was going to use heavily or in a situation where I didn't have time to position my hand correctly. It certainly gives the handle a unique look though.

[AndoCalrissian]

Did you ever make one of these? I was drinking with my buddy this weekend and had this exact idea pop in my head. He loves kitchen knives and said that the handles are always the issue so you have to make sure to hold a knife before you buy. At least expensive ones. Anyway. Never comment on these things but had to after reading this when I searched to see if it has been done. Probably a lot easier to do now than in 2009 with all the technology at our disposal. 

[ThomasPowers]

You mean you have never had them grip a roll of clay to make a model to work too?  May date back to 0009 for all I know.

[George N. M.]

Ando:  Yes, you could make a knife handle from the impression your hand makes in a soft material, clay, plastic, soft rubber, styrofoam, etc., and it would fit YOUR hand exactly.  However, it might not fit anyone else's hand very well except maybe your identical twin.  Also, it would be a rigid fit with the blade being in an exact relationship to your hand.  However, you probably shift your grip a bit on a knife depending on what you are doing.  Chopping wood will require a different grip than doing something fine.  And if you are working on a complex shape you are shifting your grip all the time.  I don't know if you are a hunter but dressing out a game animal requires a lot of different geometries of hand and blade.

So, IMO the ideal grip is a compromise and average for different hands and different tasks.  If you are making a custom knife for someone with particularly large or small hands you may want to adjust the average a bit up or down.

Back in my geology days I used a scintillator (a device, like a geiger counter, used to detect radiation) for uranium exploration.  It was pistol shaped and the handle had 5 indentations for the fingers.  It was apparently designed for a 6 fingered alien.  It did sort of look like a 1950s ray gun.

"By hammer and hand all arts do stand."

[ThomasPowers]

Even Identical Twins will have different hands due to differences in how they use them---a pianist's hands will differ from a smiths hands!

[JHCC]

13 hours ago, George N. M. said:

It was apparently designed for a 6 fingered alien. 

Or Count Rugen took up prospecting.

[ThomasPowers]

Beware the Spaniard with the mining pick or sticking tommy!