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Jonas
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So ANSYS is so complicated that in the time it would take me yo figure it out I could just work, buy some cf, and break stuff way faster. My cousin works in a dragon boat paddle company anf gave me a 20" length of tube that's about 1.5" dia. As far as I can tell it's two layers of twill at 0/90 and one of helical fiberglass on the inside. When I get time I'm going to epoxy a pipe in the end and load it at the most extreme angle the handle will see. I've tried to find studies on curved CF tube strengths, but haven't come up with anything. The paddle handle will break, but it might be helpful to see where and how. It'll be a decent starting point I think. School's been devouring my life the last week so I haven't had a lot of free time. I did get two prototype handle geometries cut out of plywood, hopefully tomorrow night I'll have some time to get on the plasma cutter and cut out picks for them. I was planning on just running the handles through a table saw to cut them in half (like if I was going to make a 2 part mold), then make the pick run the length of the handle and bolt it all together. Full-tang, just like a samurai sword. This way the steel takes the tensile load and the wood takes the tortional. Kinda want to get some time with them before they snap so I know which one to use as a template for the final. Gotta move this along or I'm not going to get them done in time for the season! Once I pick a handle I can send the CAD file to my buddy and he'll machine it for me. It's pretty much just a 20" curve with a ~16" radius, 1.25" tube width, and 0.5" radius fillets all around. I tried to make it simple for him. I found a place in town with West System 105 & 207. My dad has some General Systems #3, but I'll probably go with 105/207 for the final product for peace of mind if nothing else. He's an old guy so according to him it's all the same stuff. He's rarely wrong but I don't listen to him anyways.
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Jonas
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I have Solidworks through the school, but I know it can't really do composite simulations since the figures are different depending on the direction. However we also apparently have ANSYS 15.0 now, which I'm not familiar with, but every day's a good day to learn!
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wozza
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Without a lot more information about your design and the expected loads I wouldn't want to start recommending a particular layup, especially when another persons life may depend on it  If you are new to composites and don't have access to/experience with some decent software I would be doing some serious testing. (I would be testing anyway) Get some braided sleeve, good quality epoxy laminating resin and have a go at some wet lay over a mandrel. A vacuum cleaner extension tube makes a ready made mandrel. Because most are tapered release will be easier. Wrap a layer of paper around the tube followed by some flash breaker tape, this is your releases agent. Carefully slide the braided sleeve over the mandrel and stretch it out so it conforms to the tube. This is where you can experiment with the number of layers. Start with say a piece 1/4 of the tubes length, then one 1/2 its length, 3/4 and then finally 1 or 2 full length. This will give you the tapered wall thickness I mentioned. Wet out the fabric with the laminating resin (this is the messy bit  ) Once your happy the fibres are wetted out wrap the hole thing in heat shrink tape. Carefully go over the heat shrink with a hot air gun, the tape will contract and consolidate the laminate. Don't use too high a heat or the tape will begin to crinkle (cant think of a better word at the moment) Once cured remove shrink tape and the nice new cf tube from the mandrel, the paper and breaker tape should make this easy and test the thing to destruction (if you can ) I know a straight tube may not be your final profile but this will give you some hands on experience with cf and how it behaves. From there you can play around with the layup/materials all the time gaining experience (and having fun) without a huge outlay. Have a look at the EC fishing pole repair tutorial to get a better idea. Something to remember as far a testing goes, there is big difference between hitting something with a part made from cf and something hitting a part made from cf. Warren
Carbon Copies Ltd
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Jonas
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BRILLIANT! I'll incorporate that into the head design. I'd like to get this project off the ground relatively soon, shaft ergonomics design starts tomorrow, so the only steadfast obstacle in this project is what weights, weaves, and how many layers of fabric to use. I have little to no experience in this, and I'd love to do some kind of math or something for this, but I haven't taken materials engineering yet so I don't know how. If I could get a couple opinions on this it'd help me out a LOT. Thanks to everybody for the immaculate help you've given me thus far!
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wozza
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Yep, common in bike frames and many other applications. Slight difference being I would extend it much further down the shaft in a more gradual taper. That way you should be able to retain the flex/feel that Dravis mentions. My background is in the Aerospace/Lightweight Structures sector and as a result the philosophy of "if it has to be there make it do something, preferably more than one thing" is imbedded in me. As mentioned by others these picks seem to have a wrist strap, I assume its main function is to prevent the pick being dropped at a critical moment Why not combine the wrist strap with the fail safe tether. Run the wrist strap up the shaft all the way to the head. That way if the worst happens and the shaft breaks you still have a direct link to the head which is hopefully still stuck firmly in the ice. Warren
Carbon Copies Ltd
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Jonas
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For me I would increase the number of layers in the area where the head will attach, giving a tapered wall thickness along its length. To try and disperse any point loadings. You could add some E-Glass or similar to improve impact resistance if required. I would be concentrating more on how to attach the head to the shaft reliably.
Just like how bicycle frame tubes are butted!
I never even thought of it that way! I was planning on doing a layer or two of uni, and finish with a layer of fiberglass for galvanic protection, but completely spaced on how making them butted will make them stronger too. I have a tendency to overthink things and miss obvious details 
I would like to recommend very strongly that you use at least one layer of kevlar/twaron mix fabric in there... What you're building is a tool for "hammering" some measure of impact resistance seems vital to me .. I was still planning on this, but earlier today I was thinking about it and realized the following: If i incorporate a layer of Kevlar that runs the length of the shaft, and the shaft were to break while it was already stuck in the ice, the loading would change to something like this:  In which case the tool would probably slip off anyways. That being said, I'd still like to throw a layer of CF/kevlar weave in there in case I lend it to my roommate and he smashes it on a rock and cuts through the CF somehow. Bottom line: a layer of CF/Kevlar doesn't weigh that much, doesn't seem like it will be hard to include, and won't make things worse. And as long as I'm not making things worse I'm doing okay! Running kevlar tows between the ends seems like a good idea, but I'm not sure how I would get the tows between the two inserts not only taught, but tied off none the less. I considered placing an eyelet on each insert, attach the two with a piece of spectra/dyneema or even basic nylon webbing, epoxy the head in, then twist the bottom insert until it was against the bottom of the shaft, and epoxy it in place. The webbing would still have enough give to let one insert pop out though, thus negating most of the benefits. If I could come up with a way of attaching the inserts so that they're tight inside the shaft I'd feel pretty comfortable climbing on them, since even if the epoxy bond were to fail the inserts would remain inside the shaft and since it's an oval they'd be unable to twist. Currently I feel as though there's two ways that this design can fail that are far more likely than any others: 1.) The CF fails at one of the pressure points on the head. 2.) After enough thermal cycles, vibrations, and impacts, the epoxy bond between the head and shaft fail, resulting the head pulling out from the shaft. I think that with Warren's idea to make the tubes butted, with extra uni and E-glass, the shaft failing is becoming considerably less of a hazard. This leaves the issue of the head pulling out (oh man...), but thanks in part to Brian I think I've got something to help out with that too.  So Brian came up with cutting horizontal slots in the head insert. (Everything you're about to read could actually be a terrible idea, and I just don't know it. It's a good deal of speculation.) I was originally planning on hollowing it out, but this is a lot less labor-intensive and I believe is quite a bit stronger as well. I realized that I could run CF tows through these holes prior to epoxying it into the shaft, wet them down, and epoxy it in. Ideally the fibers would be running DOWN instead of UP, but ya can't have everything. Depending on how many tows I use I assume I'd have to taper the insert a little bit to accommodate their width while still holding 0.01" gap around the edges for optimal adhesion, but I thought I'd pitch the idea and see what everyone thinks. This could pose an issue with galvanic corrosion, so I'll do some research into how well spectra/dyneema bonds with CF and how well it handles compression in a matrix, but I thought it was an interesting idea; kind of like Dravis' idea of tying the two together with kevlar, but...reversed. Shaft flex is something that's been of slight concern. My old roommate plays hockey, and I remember him telling me how the CF hockey sticks he has actually bend when he hits the puck with them. As he swings, the blade lags behind the shaft, then snaps forwards at just the right moment to hit the puck, meaning you have the kinetic energy of the stick, plus the kinetic energy of the blade snapping forwards. Cool stuff! I'm not sure how to factor this into my picks though, it seems like the only way to figure it out is trial and error; keep trying different layups until it feels right. I think I have a decent margin for error though, since most of the ice climbing I do you don't swing your picks like you're driving framing nails with a hammer, but more like you're driving finishing nails. Two or three relatively light taps to chip away a little ice is all it takes; a couple millimeters of ice will support your bodyweight pretty easily. I have a chemistry lab report due in an hour and a half (We weighed water  ...) so I'd better get to work on that. Thanks for the help everyone! Slowly the idea progresses to eventual fruition!
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wozza
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Dravis, liking the kevlar rope idea Only seen a small/lightweight high tensile cable within the shaft connecting the head to the bottom spike as a fail safe. Warren
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Dravis
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"questionable bond between aramids, CF and resin" ... That is precisely why I recomment using a mixed weave like the Twaron/CF, that way you will have unbroken Aramid fibres running the length of the shaft.
While they may not contribute as much to the ultimate breaking strength of the shaft, they will keep it together, even if it does break, and may still leave the climber something to hang on to ...
Ideally you should run several strands of kevlar Tow through holes in the metal alloy inserts that you bond into the ends of the shaft, in effect tying the metal inserts together with a nearly unbreakable kevlar rope.
Now, I do not know your particular climbing style but, as far as I have seen, most ice climbing is done using loops attached to the handle ends of the ice-axes, so you really need at metal insert at that end too.
When you use an axe and have to place very precise strong blows to anchor the point, the flex of the shaft becomes important too, if it is too stiff, it will be very tiring to use, jarring your hands.
"Sapere Aude"... Dare to KNOW!
The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind...
103% of all people do not understand statistics...
Do not adjust our mind, theres a fault in reality :-)
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wozza
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Dravis (13/10/2014)
I would like to recommend very strongly that you use at least one layer of kevlar/twaron mix fabric in there... What you're building is a tool for "hammering" some measure of impact resistance seems vital to me .. Also should the CF in the handle break, the kevlar will keep the parts together, which may leave the point embedded in the ice, and you hanging off it still...  The bond between cf and aramids can be brought into question, again needs careful thought and a degree of experience/research.  Warren
Carbon Copies Ltd
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Dravis
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I would like to recommend very strongly that you use at least one layer of kevlar/twaron mix fabric in there... What you're building is a tool for "hammering" some measure of impact resistance seems vital to me .. Also should the CF in the handle break, the kevlar will keep the parts together, which may leave the point embedded in the ice, and you hanging off it still...
"Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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