WaterJet Cut Blades

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rprocter

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i would like to understand how the work of making a Folder is affected by the maker purchasing waterjet cut blades. some consider this means the knife is not a custom, but that is not what i am inquiring about.
1) does the maker send the cutter a detailed drawing with exact measurements of the blade(s) he wants cut ?
2) are the blades cut in profile only or is there also a cut made to taper the blade from spine to future edge ?
3) what must the knifemaker still have to do to turn it into a finished blade ?
4) what steps does the knifemaker NOT have to do compared with cutting out the blade himself (i.e., in part i am asking what steps are involved for the maker to cut his own blades)
5) what are the reasons for using waterjet cut blades ?
thank you. your replies will greatly help me to better understand what is involved with the making of a blade.
roland
 
I do NOT make folders, but I am familiar with waterjets...

1) Yes, a CAD file in dxf or dwg format would be ideal for most WJ shops
2) profile only, with very few exceptions
3) same as any knife - read stickies. Some portions of the blade edge may need to be machined or ground (i.e. the WJ cut may be too rough, or out-of-square for precision mechanisms).
4) read stickies - most people use a bandsaw to cut an approximation of the profile, then grind to final shape/size
5) Parts are identical; often cost-effective if one factors in a labor rate on their own labor.
 
Roland.. not much different than using a bandsaw or plasma cutter to cut the blanks yourself. Mainly a cost savings issue, there's still a LOT of work left to do after getting the parts in. Rest assured it still takes a "maker" to get the parts into something resembling a knife.
 
what is the value of a "hand made" knifeif it neither looks good or is not well made. Many, many makers are having blades and frames and whatevers water jet cut and are selling there limited production folders for well over the $1000 mark. So what is the problem? It doesn't matter who or how or with what the knife is made but how good is it. Do you get upset that some of the "factory" knives look better than hand made ones and may sell for less or more ? Quality, man, quality, is what counts. Me? I make liner locking folders and no I don't have parts water jet cut, but maybe I should, and I don't even have a surface grinder which is often concidered to be a very necessary peice of equipment for doing this work. Yes, some of my folders do sell for $1000 or more. Frank
 
You save money and make better use of your sheets of steel using Waterjet or laser services. In effect you make more money too because you can nearly double the amount of blades you can get from a sheet of steel at times by using a service compared to say cutting it out yourself with a band saw which of course means you have more to sell when completed.

About the only thing I'd suggest when having blades cut out by a service is to remove the tabs before sending them off for heat treating. What I've found is that if the tabs on some blades overhang slightly they can cause the blade to be off center in your folder when you go to assemble them. The reason being of course that the clamp can't make it flat since the tab prevents it and you end up with a bowed blade. Otherwise I highly recommend it and can't think of any reason why you should worry about it being custom. Its still custom and still your design.
STR
 
rprocter said:
i would like to understand how the work of making a Folder is affected by the maker purchasing waterjet cut blades. some consider this means the knife is not a custom, but that is not what i am inquiring about.
1) does the maker send the cutter a detailed drawing with exact measurements of the blade(s) he wants cut ?

Perhaps, but it is more common to send a CAD file in an industry standard format such as IGES or DXF

2) are the blades cut in profile only or is there also a cut made to taper the blade from spine to future edge ?

profile only

3) what must the knifemaker still have to do to turn it into a finished blade ?

Everything except roughing out the profile. The profile still needs to be finished, the bevels ground, the pivot hole reamed or ground, heat treat, finial finishing and lock face grind.

4) what steps does the knifemaker NOT have to do compared with cutting out the blade himself (i.e., in part i am asking what steps are involved for the maker to cut his own blades)

The hand work involved in roughing out the profile is skipped.

5) what are the reasons for using waterjet cut blades ?

If you're making a lot of something, consistency helps speed things up. Less room for error. Better yield out of the sheet.

thank you. your replies will greatly help me to better understand what is involved with the making of a blade.
roland
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That said, I feel it is probably a little less "hand made" (though I'm one to talk:rolleyes:). The less room for error means perhaps slightly less skill involved. But the work cut out was the easy part. The stuff remaining is the skilled part.

In case anyone is wondering - a water jet pivot hole is no good - it still needs to be machined.

To me, the biggest concern, that nobody talks about, is the fact that CAD is used instead of the hand and eye to develop the shape. Hands and eyes don't make straight lines and constant radius curves. Water jet stuff looks artificial to me because the CAD used in the design. That, and people who are artists with their hands are frequently clumsy designing in a computer. I feel that a lot of folks who have stuff water jet have stuff that doesn't look as smooth, organic and well proportioned as their usual work. This is less a function of the water jet and more a function of an artist working their art in an unfamiliar medium.
 
Even with 'tilt-a-jet' technology, waterjet is very much an "intermediate-precision" technology with tolerances of +/- about .003 (so they say) but in practice I have not found that to be something you can count on.

When I use waterjet, I have parts cut .05 oversize and never do holes in waterjet. It's a roughing operation to me--nowhere near a finish operation (unless you're doing some pretty coarse work.) I think it's best to cut the holes in the oversized blank and locate off those for cutting the other contours. That way your holes and edges will actually be perpendicular and properly located.

So for me, the primary advantage in WJ is savings on material. You can nest parts closely on a sheet and eliminate a lot of waste on valuable materials (like CPM products and Ti) compared with cutting it from bar, but you're still just blanking with this process.

For what it's worth, I have no use for something that is "handmade" for the sake of being hand made. I've seen plenty of inferior stuff that's supposed to be great because it's "handmade". I'm much more interested in making the best possible product in the most efficient way. Sometimes that means CNC, sometimes it means forge and hammer.
 
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I too do not use any laser or waterjet cut parts,and don't have anything against
it untill we come to sole authorship. If x number of people were asked what a square
piece of barstock was alongside the profile or waterjet cut of a knife blade I wonder what that poll would show?
Ken.
 
kc custom said:
I too do not use any laser or waterjet cut parts,and don't have anything against
it untill we come to sole authorship. If x number of people were asked what a square
piece of barstock was alongside the profile or waterjet cut of a knife blade I wonder what that poll would show?
Ken.
Click to expand...

Just to play devils advocate here. I don't see the difference between them in terms of sole authorship provided you own the waterjet machine and you created the drawing to be sent to waterjet. There is no difference between cutting the outline of a knife with a water jet or a bandsaw we just use the tools we have access to. I don't have access to a HT oven so I send my stainless blades out to be heat treated for my O1 blades I heat treat them in my forge. I could easily see that knives made by David from Great Lakes Waterjet could be claimed by him to be sole authorship assuming he did all the grinding and heat treatment himself.
 
It's kinda like buying a custom motorcycle if you want something one of a kind or something not everyone else has, made by hand and with a more passion and art and be 1 of 1. Or you could just buy a Harley that is stamped out on an assembly line, can still order some custom parts but limited to specific designs and be
1 of 5,000.
 
1sharpedge said:
It's kinda like buying a custom motorcycle if you want something one of a kind or something not everyone else has, made by hand and with a more passion and art and be 1 of 1.
Click to expand...

The allure of a "one-of-one" piece is perfectly valid.

However, I'm not sure one-of-a-kind pieces are particularly more likely to be made with "more art"--or even greater quality, skill or attention to detail, for that matter, than high-quality short production, neo-custom, or whatever you'd like to call it (I'm not talking mass-production. I'm talking about the Ken Onions, Todd Beggs, Sibert, etc. --- Guys using modern methods to produce great high-quality knives.)

I did sole-authorship pattern-welded pieces full time for 10 years AND have produced short-run production. IMO, building knives "open class", to use a motorsports term, (using whatever applicable technology or service that delivers value to the end product) requires at least as much skill (and usually a lot more knowledge) as the "sole authorship" approach.
There are skills unique to each just like the hacksaw-and-file approach requires different skills than the bandsaw-and-belt grinder approach.

Waterjet is not a magic short cut. It's a good blanking/roughing process that lets you save material and some time on the mill or grinder, but if you're just doing a few pieces, forget it. Just scribe 'em out of bar, saw and grind to the line. It's faster and cheaper (with minimums, shipping, etc) and you can tell everyone how it's "hand made". :thumbup::rolleyes::)
 
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Thanks to all of you fine folks for taking the time to give excellent clear responses to my questions. i now do understand the relatively minor role WJ cutting plays in building a knife.
i have no background or experience with metal working of any sort, so i much appreciate the help with the basics.
roland
 
JCaswell brought up some good reminders to adopt if you use a blanking service. I usually have the pivot hole, the detent in the lock if its that type of folder, and the stop locations all spotted for me. The rest including clip screws I like leaving off and I do all that myself. Its a good idea I think to have the pivot at least spotted on your folder scales and liners because after that you can really place all the others fairly simply but many do as Joe suggested just having them blanked out with no holes spotted.

You can get your foot in the door to folder making via several ways. How you get your foot in the door should not matter much whether it be through laser, waterjet, plasma torch, bandsaw, or old fashioned hacksaw and file work to cut and shape all your parts. Once you have your parts cut out no matter the method used to get those raw materials shaped into usable parts, they are still a long ways from the finish line and if you can't make them work one way it won't be any easier the other so its not going to have anything to do with how they were originally blanked as to the quality or marketability of your knives. Making it all work in a reliable, usable, yet wonderfully artful good looking piece is where all your skill and knowledge comes into play.

Most of the guys I know have at least one proto-type they did first that was copied later by a service or saved to a CAD program by the maker. The first ones are usually sole authorship if there is such a thing but in most all cases you'd be hard pressed to tell one from the other.

STR
 
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