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Title: Project Idea Post by: NEIKOS on January 20, 2009, 12:15:49 PM I'm thinking of attempting to make myself a titanium bladed, carbon fibered handled knife.
Anyone have any knowledge about metal casting or carbon fibering? Title: Re: Project Idea Post by: ryandalling on January 20, 2009, 12:18:41 PM Don't do it. You might cut yourself. [laugh]
Title: Re: Project Idea Post by: duc_fan on January 20, 2009, 05:51:26 PM Titanium is notoriously difficult to work with. You won't be casting it at home, nor even in any "normal" casting facility. Ti requires significantly higher temps than steel.
Ti is also ugly to machine. Some shops won't even touch it. If your heart is set on a Ti blade, I'd be trying to find a chunk of Titanium that very nearly resembles the desired final shape. If you want something you can work yourself, you'll need to stick to a softer metal. CF is significantly easier to deal with. Pick up a copy of the Aircraft Spruce catalog, and check out the available composite cloths that are available. Unless you've got an autoclave, or an oven you don't care about, don't bother with pre-preg (which is fiber cloth pre-impregnated with resin). Get plain cloth, then you'll need an appropriate resin. You'll have to determine what material properties you're looking for (fast set, slow set, very hard but brittle, medium hardness with a little give, soft with lots of flexibility, etc). I'd imagine in a knife handle that you want something with a little give to it, so it doesn't shatter the first time it gets dropped on a hard floor. We can easily wrap a knife handle with CF fabric and resin. We could probably even get creative and vacuum-bag it (reduces air bubbles, resulting in a better looking and stronger finished product). The biggest challenge will be creating the knife blade, and as I said earlier: if'n you want a Ti blade, you'll need to find it pretty much finished, because there's no way for us mere mortals to work Titanium in the average garage. Title: Re: Project Idea Post by: Betty Rage on January 20, 2009, 06:19:34 PM My brother is a welder and works with many different kinds of metals along with CF. I can put you in contact with him.
Title: Re: Project Idea Post by: Mother on January 20, 2009, 11:02:37 PM Or
you could go with bone and steel... I made this one in high school The blade is a piece of a blade used to cut metal composition unknown and a frightful nightmare to work but it rarely rusts and when it does it just gets minor black spots It is a 5 1/2" Drop Point Flat Grind with a half tang The Quillan is brass and mostly unfinished The hilt is Deer I was unable to drill the tang so it is fixed into the hilt with epoxy (http://farm4.static.flickr.com/3382/3215020090_22231a327b.jpg?v=0) (http://farm4.static.flickr.com/3382/3214172101_590f1787ed.jpg?v=0) (http://farm4.static.flickr.com/3488/3214172063_1f7d95e437.jpg?v=0) (http://farm4.static.flickr.com/3381/3215020158_82209475fd.jpg?v=0) I would highly suggest you invest in a machine to do your polish this one is done by hand to 2500 and it took a considerable amount of time Title: Re: Project Idea Post by: oregunduc on January 21, 2009, 08:36:34 AM I like the book in the background of the last picture: Are you a miserable old bastard?
Title: Re: Project Idea Post by: jdubbs32584 on January 21, 2009, 08:38:29 AM I like the book in the background of the last picture: Are you a miserable old bastard? only when i'm not around. [thumbsup] ETA: wait, maybe that should be: just when I'm around. [laugh] Title: Re: Project Idea Post by: JohnnyDucati on January 21, 2009, 12:32:46 PM I'm thinking of attempting to make myself a titanium bladed, carbon fibered handled knife. Anyone have any knowledge about metal casting or carbon fibering? Is 22 years enough experience? 8) Title: Re: Project Idea Post by: JohnnyDucati on January 21, 2009, 01:03:01 PM Titanium is notoriously difficult to work with. You won't be casting it at home, nor even in any "normal" casting facility. Ti requires significantly higher temps than steel. Ti is easy to work with given the proper knowledge and equipment. True - you can't cast it at home unless you have a vacuum chamber furnace. They only run about $1.5 to $3.0M, depending on if you have the vacuum pumps. Also, you'd want to use forged billet Ti, anyway, not cast, for better blade properties (grain size, etc). If you go with cast material, you will need it to be Hot Isostatically Pressed (HiP'ed) to eliminate any possible inherent porosity. Or, likely not, because that is a very expensive process with only a handful of locations in the free world that perform that process. Ti melts at only 100 or 150 degrees F more than steel. That's not a significant amount, and that's not the problem, though. Besides being unable to super-heat during the melt phase (due to having the same liquidus and solidus point), the primary challenge with molten titanium is that it is extremely reactive (think of raw sodium in water) and reacts with everything it comes in contact with, including the melt crucible. Ti is also If your heart is set on a Ti blade, I'd be trying to find a chunk of Titanium that very nearly resembles the desired final shape. You will need high grade grinding media and equipment and dust control because you or your children do not want to breathe the waste dust. If you want something you can work yourself, you'll need to stick to a softer metal. I would second this comment. CF is significantly easier to deal with. Pick up a copy of the Aircraft Spruce catalog, and check out the available composite cloths that are available. Unless you've got an autoclave, or an oven you don't care about, don't bother with pre-preg (which is fiber cloth pre-impregnated with resin). Get plain cloth, then you'll need an appropriate resin. You'll have to determine what material properties you're looking for (fast set, slow set, very hard but brittle, medium hardness with a little give, soft with lots of flexibility, etc). I'd imagine in a knife handle that you want something with a little give to it, so it doesn't shatter the first time it gets dropped on a hard floor. We can easily wrap a knife handle with CF fabric and resin. We could probably even get creative and vacuum-bag it (reduces air bubbles, resulting in a better looking and stronger finished product). The biggest challenge will be creating the knife blade, and as I said earlier: if'n you want a Ti blade, you'll need to find it pretty much finished, because there's no way for us mere mortals to work Titanium in the average garage. Well said. Actually, you can have your cake and eat it, too, in this case. In fact, you can cut your cake with a Titanium COATED knife (with a steel blade). Make your knife out of typical steel and then have it coated with titanium nitride. Any number of vendors out there that do that. Or, just buy one of the 'ucking things off the shelf. I have a Gerber with Ti-nitride coated blade. There you go. Save yourself a lot of time, money, hassle, and carcinogenic contamination. ;) Best regards, JohnnyD Title: Re: Project Idea Post by: SaltLick on January 21, 2009, 01:05:56 PM good lord man just go down to Kmart and buy a pocket knife.
Title: Re: Project Idea Post by: duc_fan on January 21, 2009, 01:40:34 PM Apparently Johnny D has had a different experience with Ti than my other machinist friends and aeronautics material science professors. Having the right tools makes all the difference. It's probable the other folks I know didn't have the right tools for working with Titanium.
My info is from friends. Johnny's is from working with it himself. This is a no brainer. We still don't want to mess with it in the average garage. ;) I like JD's idea of making the blade of steel then having it Ti-nitrided. [thumbsup] Title: Re: Project Idea Post by: JohnnyDucati on January 21, 2009, 05:52:49 PM Apparently Johnny D has had a different experience with Ti than my other machinist friends and aeronautics material science professors Those that can, do. Those that can't, teach. . Having the right tools makes all the difference. It's probable the other folks I know didn't have the right tools for working with Titanium. My info is from friends. Johnny's is from working with it himself. This is a no brainer. We still don't want to mess with it in the average garage. ;) Right on. I like JD's idea of making the blade of steel then having it Ti-nitrided. [thumbsup] Title: Re: Project Idea Post by: NEIKOS on January 23, 2009, 06:33:00 AM Well shit . . . another shattered dream.
Title: Re: Project Idea Post by: ryandalling on January 23, 2009, 08:27:43 AM Well shit . . . another shattered dream. Is that like the one where you wake up and are six foot tall? I have a dream where i wake up and I am a nice guy and people like me. Unfortunately, I think I have perfected the art of being a bastard. [thumbsup] Title: Re: Project Idea Post by: marvellous on January 23, 2009, 10:57:53 AM You'll 'cut' your eye out kid...
Title: Re: Project Idea Post by: duc_fan on January 24, 2009, 03:16:35 PM Okay... this has been bugging me.
I wasn't talking out of my a$$ about Ti being hard to handle. If I don't know what I'm talking about, I try to make note of it (example: when discussing racing or handling techniques, if I say anything, I usually make a comment to the effect of "but I'm not a racer"). On the subject of working/machining materials, I have an uncle who owns his own machine shop. He's a second-generation machinist, knows his crap. He doesn't work with Ti, because it's more difficult to work than other metals, and he didn't want to invest in the equipment to do so. Also have a family friend who's been a machinist for 20-odd years. Heck, about 5 years ago he bought a 6-axis CNC mill that his company was getting rid of, and he put it in his garage. He now tinkers with it, making custom parts for his cars and his Harley. He even started selling some of his custom Hog parts online. He's worked with Ti before and his opinion is that it's a pain to work with professionally --even a properly equipped shop has to be careful-- and as I stated earlier, it's practically impossible for the hobbyist. I also got to know the machinist on campus at Embry-Riddle. He'd been around milling machines for... God, I don't think any of us knew how long. One of those grizzled old veterans. His opinion was it was "difficult" to work with in a well-equipped shop, and darn-near impossible in ERAU's more basic facilities. As far as "Those who can, do, those who can't teach"... while I would normally agree with this sentiment, it does not apply to the professors at ERAU. I don't expect JD to have known this, but if he did, then that statement was insulting. All but one of them (in the College of Engineering) had a minimum of 10 years working in the industry before the school hired them, and the average was more like 20 years. The only exception (Dr. Hayashibara) had 10 years working for a subsidiary of Toyota as a mechanical engineer, before coming to the US and getting his advanced degrees in the Aerospace realm, and then he came to work at ERAU without significant aerospace industry experience. But... he did have 10+ years of experience working as an engineer in another specialty. These men and women came to teach only have they had proven for more than a decade that they could "do". Come to think of it, there were a few who were brilliant, but not great as educators... they could "do" far better than they could teach. I know most of academia isn't like that, but this is one of the reasons I went to Embry-Riddle. It's more about practice than academics. Sorry about the rant, but I don't like being made a fool of. Johnny, I'm sure that wasn't your intention, you're a nice guy, but this was bugging me. I only spoke on this subject because I felt that I do, in fact, have a clue. Okay, back to your regularly scheduled --and far less serious-- DMF hooliganry. Title: Re: Project Idea Post by: NEIKOS on January 24, 2009, 07:13:05 PM Anyone got CAD skills that'd be interested in maybe doing up the knife blank?
Title: Re: Project Idea Post by: Mother on January 25, 2009, 02:30:37 AM steel, file, paper, and time = knife
Title: Re: Project Idea Post by: NEIKOS on January 25, 2009, 07:27:42 AM CAD design+Ti scrap+prototype service w/ water jet cutting machine+custom carbon fiber wrapped handle=cool one off personalized boot knife or 2. I'm thinking twins . . .
Or if anyone's else is interested maybe a few "special reserve" pieces. Title: Re: Project Idea Post by: SaltLick on January 25, 2009, 08:26:25 AM im telling you the dollar store has a sale on TI knives. [thumbsup]
Title: Re: Project Idea Post by: marvellous on January 25, 2009, 01:03:37 PM I think the point you're missing, Salty, is that CT is a bit... how do you say... stubborn? :P
I don't know anyone ELSE like that at ALL, either... [drink] oh and mmm... ( . )( . ) |