DIY Walking Axe
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Paul Tree
(Paul_Tree) - F

Locale: Wowwww
Re: Ti/carbon "B" rated axe... on 11/09/2007 10:55:52 MST Print View

I showed the chamfer on the wrong side. It should be ground off the bottom. Also, it should probably not be squared off, a (blunt) point will help focus the energy, good since it will likely bounce off hard ice.

There are surface treatments to harden aluminum. Possibly hard anodizing: http://www.wisegeek.com/what-is-hard-anodizing.htm

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Besides the curve on the arrest-thumb-position, it'd be comfy to not have teeth on the 4 or 5 inches near the because thats where your hand gets lots of action in arrest.
Since it is not such a technical axe as your Nanotech, that is appropriate. It's tempting to eliminate the adze. There is some use on loose snow/slushy snow when it might work, but you probably don't want to chop an ice hole or a ton of steps anyway.
piolet adze annot

Edited by Paul_Tree on 11/09/2007 15:35:54 MST.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: Re: Ti/carbon "B" rated axe... on 11/09/2007 14:27:39 MST Print View

> There are surface treatments to harden aluminum. Possibly hard anodizing
That will harden the SURFACE only.
When you hit a rock, the underlying softer aluminium distorts and the hard anodising flakes off. That's what happened to my Helix.

Cheers

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re: Re: Ti/carbon "B" rated axe on 11/09/2007 14:59:39 MST Print View

Not to worry gentlemen - I am going with Ti on the next one.
And what do you know - the Titanium Joe guy is just down the street from me (3 hours)! Finally...cheap shipping and no extra charges.

Paul Tree
(Paul_Tree) - F

Locale: Wowwww
Re: hardening on 11/09/2007 15:56:40 MST Print View

Hey Roger, since brittleness is proportional to hardness, probably better to avoid trying to get the whole thing hardened too much. At least the pick didn't break!

So surface treatment came to mind, but as you say, the underlying stuff wont support major impact. Even a nice steel would get beat up with enough fun. Same with crampons: with aluminum, keep to the ice.

It would be interesting to try a long shaft, since so light anyway, and it seems a walking axe. Longer will see more use.

It would also be nice to have it be a replaceable shaft in case of breakage etc, maybe a soluble glue, or meltable or something.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: Re: hardening on 11/09/2007 17:30:32 MST Print View

Hi Paul

> Even a nice steel would get beat up with enough fun.
Try hammer steel: MADE for the task!

> It would be interesting to try a long shaft, since so light anyway, and it seems a walking axe. Longer will see more use.
Yes, definitely. The length was the major limitation of the Helix as a walking axe. I didn't get the longest one becasue of problems with air transport. This may have been a mistake.

> It would also be nice to have it be a replaceable shaft in case of breakage etc, maybe a soluble glue, or meltable or something.
24 hour Araldite. It bonds very well to the CF and the metal, and it can be softened by heating to about boiling point - enough that you can wring the bits apart. Don't know about other brands, but quite probably.

Cheers

Paul Tree
(Paul_Tree) - F

Locale: Wowwww
carbon tubes on 11/12/2007 23:49:49 MST Print View

LuxuryLite sells a 48" SurvivalStik, the owner seems helpful, may sell a blank.
http://www.luxurylite.com/ssindex.html

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Update: Ti/carbon "B" rated axe on 11/13/2007 06:18:47 MST Print View

I redesigned the head of the axe using titanium and the shaft using carbon. I couldn't go with the one piece design with this material. Too expensive, and too difficult to make.
It is currently the same style as my first head with some modifications - ie. no teeth close to the shaft for Paul :)- but I ran it (simulated) through all the UIAA tests and there is only one test that it fails (safety factor of 0.5).

http://www.uiaa.ch/?c=310

See...ice axes (EN13089) - first pictorial page, bottom right hand corner - "fix first 25mm of pick and apply 127N load 330mm down the shaft". I beefed up the head thickness by 50% and it still failed. I'm going to dig into it as there is a comment below the test that I noticed afterwards regarding permanent deformation.

I'll post a jpeg and perhaps get some feedback tonight. I'm still working on the adze, as I want to find the sweet spot between minimal and useful (if there is one).
Ordered the titanium yesterday from Tie Joe (great guy by the way - Thanks Roger) and am just waiting for more material properties from macqc before placing that order.
Keep you posted!

GARY JACKSON
(ASMjackson) - F

Locale: Orange County
Re: axe comments cont... on 11/13/2007 19:25:06 MST Print View

You were trying to 'coat' the handle so it would not transfer cold to your hand.

I do not know if it would add too much weight compared to heat shrink, but if you thinned the "Plastic Dip" used for tool handles so you got a reeeeeal thin coat... You could experiment with that.

As far as the lexan rod, then you would have to mount an L.E.D. on the top so it glows at night through the holes to illuminate your path (I know, too much more weight)

Cool looking project!

Edited by ASMjackson on 11/13/2007 19:38:48 MST.

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Design review: Ti/carbon Axe on 11/14/2007 11:04:26 MST Print View

The head is passing all but one of the UIAA tests, but input is always appreciated before I go and cut the Ti (which I should get early next week).

Paul, no more teeth where the hand goes, and a nice chamfer on the underside of the adze which ends in a "point" for better penetration.
With the current carbon fiber I have sourced, I can make any length (within reason) with a weight penalty of 2.15 grams/inch.

Front

side

back

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re:Re: axe comments cont... on 11/14/2007 11:06:33 MST Print View

Gary,
I've actually used that stuff before for tools. I should see how much is weighs (thinning is a possibilty). Definitely a good grip with that stuff.
Thanks,
Steve

Paul Tree
(Paul_Tree) - F

Locale: Wowwww
test failing:? on 11/14/2007 12:19:18 MST Print View

what test is it failing?

The business end on the pick looks a bit thin and pointy, that little thorn. Also, I've been looking for confirmation on the adze. So many have a square adze, might be preferable for single-chop efficiency?

The 30* angle might be a little acute:

Check out Stanley's Helios Ti axe. Love the bottle opener.

PS on the adze bevel, on the (beautiful) CAD drawing, just noticed it is a single straight across bevel leaving the shoulders squared, not sure if that's what you wanted.

The splintery carbon may like a ferrule cap containing it, if the connector has beef for that. Possibly a separate ring glued over instead?? Like:ferrule

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re: Test Failed on 11/14/2007 13:09:16 MST Print View

Here is a picture of the test it fails. Can only take about half the load.

Failed Test

Regarding the other comments.

The chamfer is just straight across because it will be easier for me to manufacture that way. I can set up for the angles, but just wanted to minimize the machine time.
I think the sharp angle will be useful considering how light the head will be - not sure if 30* or 45* would even really make a difference.
I had the shaft connection designed with the cap, but then couldn't find material with a wall thickness large enough to cover the OD and ID - unless of course I bored a hole in a solid bar (no thanks), and then I still have to put a 0.035" groove in it. You can notice the size difference between the O.D.'s in the model if you look closely. I was just going to cover it with some epoxy, but a ring would be nicer.
Steve

Edited by Steve_Evans on 11/14/2007 13:10:44 MST.

Paul Tree
(Paul_Tree) - F

Locale: Wowwww
kind of cheating.. and un on 11/14/2007 16:47:54 MST Print View

Guessing the pick deforms, maybe have the point of a tooth right at 25 mm?


Uncheating - that is still wont help pass the test but might be good in real life: If you know you will be using it right handed on ice, and placing it to your right, the axis of the head could be a few degrees off the axis of the shaft. The pick slot could be angled. More appropriate for an ice tool, got to consider a possible resulting decrease in self-arrest effectiveness.tweaker

Edited by Paul_Tree on 11/14/2007 16:48:56 MST.

Kevin Egelhoff
(kegelhoff) - F

Locale: Southern Cal
Time for the carbon tube !!! on 11/14/2007 18:01:47 MST Print View

Back from a week long trip.

Steven, tell me the ID and I will whip you up a carbon tube. The ID should be the critical dimension with the parts going into the carbon tube.
Also give me the OD just for reference and the length you want so I can design the best tube to meet the strength criteria.

Kevin !!

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re:Time for the carbon tube !!! on 11/15/2007 07:11:21 MST Print View

Ahhh, there you are Kevin ;)...yes, I have decided to go the carbon/ti route.

I'm assuming you make carbon shafts at work? or something like that?
First off, how much is this going to cost to have you "whip up" a custom one? This was supposed to be a DIY project, not a full production product :)
Secondly, what type of capabilities do you have? Can you make any shape out of carbon? Or just round shafts? Can you make a shaft with a bend in it? How about a oval tube with a bend in it?
The carbon shaft I have been looking at getting (Macqc.com) has in ID of .75" and and OD of .82". However, if you can make any size, I will change that.
In one of your first posts on this thread you mentioned the carbon being 20% stronger. The numbers passed on to me from macqc show the carbon being several times stronger then aluminum (ie. 295 ksi tensile)...can you achieve these types of numbers?
In my design, the shaft is not the weak part in any of the tests, so really, if we wanted to push it, we could thin the wall even more (if that is possible). I posted the link to the UIAA specs in an above post. Take a look at it and you will see what loading the shaft has to be able to withstand. I think the worst one is the shaft, fixed on one end, and a load of 550lbs or so @ 500mm on the other end. Let me know.
This could get really good!

Edited by Steve_Evans on 11/15/2007 07:13:07 MST.

Kevin Egelhoff
(kegelhoff) - F

Locale: Southern Cal
Carbon tube on 11/15/2007 11:40:33 MST Print View

To answer a few of your questions:

I'm assuming you make carbon shafts at work? Yes.

First off, how much is this going to cost to have you "whip up" a custom one? This was supposed to be a DIY project, not a full production product :)

A LOT ... actually if we make this simple and just do a round shape it won't cost a thing as I already have lots of tooling in the mentioned diameters. Thinking you just want a few tubes to play with, not planning on selling these ?? Going oval or with a bend can be done BUT now you are talking additional cost and I wouldn't even suggest we go down that path unless you are thinking about making and selling thousands of these.

Secondly, what type of capabilities do you have? Can you make any shape out of carbon? Or just round shafts? Can you make a shaft with a bend in it? How about a oval tube with a bend in it?

See above.

The carbon shaft I have been looking at getting (Macqc.com) has in ID of .75" and and OD of .82". However, if you can make any size, I will change that.

I have standard size tooling available without having to buy anything. .75", .6875", .8125", 1.00" etc.
OD you are looking for doesn't matter. I can make any outside diameter as that is based on the number of wraps of the carbon. 0.035" wall thickness sounds good to start with. I need to look at the head insertion depth and will look at adding some fiber orientated 90 degrees to add some hoop strength.


In one of your first posts on this thread you mentioned the carbon being 20% stronger. The numbers passed on to me from macqc show the carbon being several times stronger then aluminum (ie. 295 ksi tensile)...can you achieve these types of numbers? In my design, the shaft is not the weak part in any of the tests, so really, if we wanted to push it, we could thin the wall even more (if that is possible). YES

I posted the link to the UIAA specs in an above post. Take a look at it and you will see what loading the shaft has to be able to withstand. I think the worst one is the shaft, fixed on one end, and a load of 550lbs or so @ 500mm on the other end. Let me know.

As soon as I get a break from work I will check out the site and see what kind of loading the shaft will need to take.

This could get really good!

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re: Carbon tube on 11/15/2007 12:33:07 MST Print View

OK Kevin, we'll stick with the round shaft until I open up a factory ;)

An ideal size would be 0.6875" ID w/ 0.035" wall thickness (Ref. 0.7575" O.D.). This leaves enough meat on the OD of my Ti (0.785") to cover the cut carbon ends. The length can be 45cm for this one (the head and pick will make it 50cm).
I currently have the head inserted into the carbon shaft a depth of 0.80".
Keep me posted - and of course, include a shaft of your own personal desired length - I'll stick a head/spike on it and send it back.
Thanks Kevin.
Steve

Kevin Egelhoff
(kegelhoff) - F

Locale: Southern Cal
Re: Re: Carbon tube on 11/19/2007 15:38:28 MST Print View

Steve,
First prototype carbon tube stats:

OD. has NOT been precision ground. Not ground appears to give a nice grip feel ?? You can tell me what you think after seeing it.

Length is 19.0" as the tube has not been trimmed to length yet.

ID is 0.6875" as requested.
O.D. is 0.770" (aprox. 0.04125" wall thickness)
Lay-up of prepreg is 20% of plies in +/- 45 orientation to resist torsion in striking
20% in hoop for crush resistance
and 60% longitudinal for stiffness and strength along that axis.

40% of the build uses low resin content standard modulus material and 60% of the build uses low resin content intermediate mod.

Weight is 45.2 grams (1.59 oz) (about 48.7% lighter then the alum tube you made)

Looks to be about the correct stiffness and weight. Let me know what you think Steve.

Kevin

Edited by kegelhoff on 11/19/2007 15:59:46 MST.

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re: Carbon tube on 11/20/2007 10:01:33 MST Print View

Kevin,
Sounds great!! Perfect timing aswell...I just received confirmation that my titanium shipped today. I'll adjust the dimesnions of the axe to match what you have posted. Send me a PM regarding payment and shipping. I'll keep those interested with the results as I complete more of the project.
Thanks alot for doing this.
Steve

Edited by Steve_Evans on 11/20/2007 10:02:24 MST.

Steven Evans
(Steve_Evans) - MLife

Locale: Canada
Re: DIY axe on 11/23/2007 17:21:42 MST Print View

I received my Ti yesterday and left it with the guys to cut over the weekend. I'm going to machine the head stem and spike tomorrow. Should be able to have pics up early next week. I ended up squaring off the adze as it seemed to be the better/common design. Even using the titanium gives me a total axe weight of under 4.5 oz. for 50cm length.