How long to grind a blade?

B

black mariah

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I tried searching, but the search function is apparently hiccuping at the moment.

I just got done grinding on my first metal blade. Jeez, this is ugly... Just in general how long does it take for you guys to grind a blade? I worked on this thing for about an hour and it's starting to work its way into a knifelike shape. Still needs a lot of work before I'd consider it even halfway done though. :D I'm just curious how much time it takes some REAL knifemakers to do this.
 
I have been told by my belt supplier that some can grind out the bevel in seconds or a couple minutes. I have decent equipment and belts and it takes me about 1 1/2 to 2 hours to grind the bevel and belt finish it to 400 grit (which is the grit I stop at until after heat treating). When I first started it took me an entire afternoon or an entire evening and the results were not as good as now. It takes a determination and patience. The rest will come on its own. Be careful and respectful of the grinder. I took mine for granted and on my second blade grind I pretty near cut off my finger. Still have no feeling where the cut was. To give you something to gauge my progress by: I have ground 14 blades so far.

RL
 
A lot of it depends on what kind of belts you use and how fast you run them. I got my first grinding instructions from Ray Ennis. He uses 3m 977 50 grit belts to do his rough grinding, on an 8" wheel at 3450 rpms, which is very fast. He told me he could grind his first few blades in about 5 minutes with a fresh belt. After that it slowed down. He got about 20 440c blades out of one belt if I remember correctly.

I do most of my rough grinding on a kmg with a 12" wheel running about medium speed with the same belts Ray uses and it takes me about 10 minutes a blade with a fresh belt. I can get about 10 blades from a belt before it starts cutting to slowly for me. It takes me about half as long to clean up the grind with 220 grit belts, so before heat treat it takes me roughly 15 minutes a blade. After heat treat I probably spend 20 minutes or more finish grinding.

It takes longer to flat grind than hollow grind, for me about twice as long. A lot also depends on if the grind is going smoothly for me or not, and how much steel I am removing overall.

When I first started it probably took me twice as long and the grinds were half as good. Keep practicing and it gets easier. I am still not completely comfortable grinding bevels. Hope this helps

Kyle Fuglesten
 
Minutes? Good luck with all that! I don't see myself doing that anytime soon, that's for sure. It did go quicker once I figured out that the area between the roller and plate on the belt sander is your best friend. Rolling with that for a while since other stuff is taking precedence over a grinder.

I'm well aware of the safety issues, don't worry about that. I've worked with all this equipment for years now and NEVER take any of it for granted. I need my fingers to play guitar with. The trick is to not get to paranoid, but not too relaxed. Just approach the tool with equal amounts respect and contempt and you'll be fine, I've found. ;)
 
Myself, I am about the slowest grinder in history. I have to look at the blade after about every single pass, and my blades take forever to grind. I have, however, seen Big John Fitch grind a blade in just a minute or two. He really hogs em! I think he has some kind of homemade grinder with a 5 hp motor on it, and it NEVER bogs down, no matter how he leans into it.
 
I'm set up with 2 8" benchgrinders. One runs at 3450 rpm and has 36 and 60 grit blue wheels. The other is 1725 rpm and has 60 and 120 grit white wheels.
Generally, if I'm not having a bad day, I can have a blade of 440C thats about 3.5"long and maybe 1" at its widest point done in about 20 minutes to half an hour. Thats if I want a nice distal taper and a full hollow grind.
On more simple stuff, I think the best I've done is about 15 minutes.

Back when I was using a 4X36 beltsander, it was more like 3hrs or more :eek: It only ran at 2100 ft/min (which is friggin slow, when you figure the surface of a wheel on my 3450 rpm grinder is doing about 6900 ft/min!) and I couldn't get good belts. I don't miss those days one bit! :)
 
I'd say it averages about 30 minutes to get one ready for heat treat. I'm pretty slow and rarely go above 20% on my grinder speed.
 
I'm fast on one side, and slow on the other. Sometimes it seems like it takes me forever to get my bevels right, and other times it all seems to fall right in place. :D
 
On my small folder blades it takes me about 15 to 20 minutes, but it only seems like about 5. However, on larger fixed blade knives it takes me an hour or so, and it seems like 3 days! -chris

__________________
Chris Crawford Knives

 
Well, on my latest big Bowie I spent about 2 months grinding on it on and off in the evenings. I was using a big handheld angle grinder for all the rough work, which presents its own set of problems. The thing weighs about 5 or 7 pounds, but to my forearms it felt more like a ton after an hour straight. I thought they'd look like Popeye's before it was finished. Also, I had to be extra careful since that big disc could easily eat a DEEP gouge in the steel if I let it slip one single time. And, since the knife is 24" long, I had to check it constantly to make sure I kept everything straight and even. It really paid off in the end though, because when I sent it to Joe Walters for heat treating (he transformed my blade into bainite)he could not believe how straight, ripple free, and even the surfaces were. He says he gets a lot of blades from full time makers that are not nearly so well ground. (lots of problems with ripples in the surfaces) That sure was an ego boost. :D
 
I'm like Danbo. Grind look, dunk, cuss, wipe, grind. I can grind a little faster but it takes the fun out of it. Also on my grinding bench I have three grinders and it's always full of junk and other projects. Last night is a good example....grind, look, dunk, cuss wipe, catch whatever is falling off the bench, grind.:o

To answer your question, about 2 hours before heat treat!
 
I used to be the slowest grinder on the planet. I had this plastic glass full of cheap bourbon stuck in one hand that slowed me way down. It was always interesting to go out to the shop in the morning and see what the knife farries had made while I was blacked out:D .It's not really funny but it's true.
I'm shed of the glass for 5 months now and the knife farries have become much more prolific and have greatly improved their speed.

Grind, wipe, look, gulp, look, gulp, grind,gulp,look,gulp. Break for refill and repeat until the farries take over.

I feel much better now

Mark
 
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