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Mungeclimber
Trad climber
Nothing creative to say
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Jan 26, 2015 - 12:15pm PT
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Lol, beer popper testing!
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Larry
Trad climber
Bisbee
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Jan 26, 2015 - 04:15pm PT
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You've got skillz. I especially like the pin through the head itself, rather than the extraneous tangs like piton hammers have had for a long, long time.
What's the cord wrap near the head for?
And isn't the grain running 90 degrees from where it should be for prying purposes?
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mucci
Trad climber
The pitch of Bagalaar above you
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Jan 26, 2015 - 04:20pm PT
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Kitty likes the dunk!
Larry, the cord is to protect the neck of the handle when you miss the 1" in angle.
Glad you are continuing t production Dan!
Can't say enough about the quality of these beat sticks.
GET ONE!
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Larry
Trad climber
Bisbee
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Jan 26, 2015 - 04:37pm PT
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Huh I guess that's what the tangs are/were for too. I still like the elegance of the pin in the head.
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Banquo
climber
Amerricka
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Topic Author's Reply - Jan 26, 2015 - 06:32pm PT
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DMT - at DAMMERR hammers we know better than to fart around an open flame.
The cord wrap is there because I like how it looks. If you don't, it is easy enough to remove.
The cat is responsible for grain orientation - I don't question him.
Actually, I buy the handles pre-shaped and the orientation of the grain and growth rings is what it is. All I do is cut to length and turn the end down for a precise fit in the head. The handle is oval in section so only goes one way. Rotating the handle in the head shouldn't have noticeable influence on the bending strength but will change the shear strength. Shear strength is somewhat less tangent to the growth rings than perpendicular to the growth rings. As a orthotropic material, wood has three orientations for strength. The three directions are:
perpendicular to the grain
parallel to the grain and radial to the growth rings
parallel to the grain and tangential to the growth rings.
To be complete, there is also rolling shear but I won't go into that as it doesn't occur in the loading we expect.
Although there is definitely a difference between the shear strengths in the tangential and radial directions, the difference actually isn't usually large. The shear strength on a plane tangential to the rings is less than the shear strength radial to the rings. Shear strength in a plane perpendicular to the grain is very high compared to the other two.
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cragnshag
Social climber
san joser
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Jan 26, 2015 - 09:02pm PT
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OK I'm going to get the rock-prying retrofit for my Dammerr. Now I just need some good choss to liberate.
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Banquo
climber
Amerricka
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Topic Author's Reply - Feb 3, 2015 - 05:05am PT
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Cragnshag-
We can easily modify your hammer, bring it by. Supposed to rain this weekend so nothing else to do.
Finally found some data for the parallel to grain shear strength of hickory.
Average tangential shear strength is 1200 psi.
Average radial shear strength is 1300 psi
This assumes no cracks or checking.
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couchmaster
climber
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The nice thing about a hammer vs a nut tool for cleaning, is that the handle makes it SOOOO much easier to clean out cracks all day. Eventually, with a small tool, your hands become like little claws. The way to stop the claws from occurring is to use a larger tool. I've been using a Stubia Hornet Ice tool. (Adze version, not hammer version). It's pretty common in these parts. You don't want to fall and get impaled by a pick though. LOL
Adam Winslow on lead.
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Roger Brown
climber
Oceano, California
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Dan,
I tried to e-mail you but it may have gone to spam. If you give me an address I will send you one of my new tuning forks. Way better than last years model, better steel and more compact.
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Banquo
climber
Amerricka
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Topic Author's Reply - Feb 3, 2015 - 07:51am PT
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Roger,
I'm easy to find via Google
danielmerrick
at
gmail
dot
com
Let me know if you need a DAMMERR hammer.
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Ken
Trad climber
Arroyo Grande
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To get oval handles when you're spindle turning between centers, mount one or both sides off-center to get the oval effect. You would need enough stock to start with obviously.
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Studly
Trad climber
WA
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Couchmaster, you guys are just a little to bold in the choss. I've done some of your routes and I have just one question, is poison oak a legitimate handhold like moss?
Sorry, thread drift!
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steelmnkey
climber
Vision man...ya gotta have vision...
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Email sent.
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Banquo
climber
Amerricka
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Topic Author's Reply - Feb 3, 2015 - 04:21pm PT
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Demand for DAMMERRs is up to about two a week for some reason. Here's a photo of all the hammers I have on hand.
Also a drill holder. I still have a few of these.
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Banquo
climber
Amerricka
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Topic Author's Reply - Mar 1, 2015 - 08:57pm PT
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Have some more hammer heads done.
Also, I've figured out a handle I can make that improves (I think) on some of the shortcomings of the various handles I have been buying. I simply can't find an off the shelf handle that is exactly what I want. I've figured out a way to make handles that isn't perfect but I think is better than what I can buy. The main issue some have brought up is that the grip on the more recent hammers has a fairly round cross section and some say they prefer an oval or other shape grip that lets them feel which way the hammerhead is pointed.
Sourcing hickory stock material for the handles isn't easy so if anybody has a source of good, dry, straight-grained hickory, let me know. I'd be happy to trade hickory <-> hammer.
I'll want to find some people to try out the new handles pretty soon.
Some people wonder why I don't have eyebrows:
[Click to View YouTube Video]
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deuce4
climber
Hobart, Australia
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Love seeing you doing your own heat treatment. Way cool.
I think though an essential feature of a wall hammer is tangs. A hammer is such an essential piece of gear on a remote wall, failure's not an option. Every hammer i ever had without metal tangs to hold the hammer securely seemed to loosen and fail after serious heavy use.
Is there any way you could develop some curved tangs for your round hole, without having to change your design too much?
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Banquo
climber
Amerricka
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Topic Author's Reply - Mar 2, 2015 - 08:15am PT
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Deuce4,
Tangs are hard to make and, I think, make the head hard to fit perfectly tight. I thought no tangs was one of the things that made the McDevitt hammer drill faster in my tests. Also, although the hammers will pound pitons, my attempt was to optimize them for drilling.
I turn the handles on a metal lathe so the fit is perfect. I then press the head on, press the wedge in and drill for the pin. Lastly, I soak the end grain with boiled linseed oil which I hope minimizes moisture change. When linseed oil polymerizes, it actually increased a bit in volume. The heads are fit as well as I can get them.
I agree that a hammer failure could be a disaster on any climb. I am concerned about both the head flying off and the handle breaking. To keep the head from popping off, I have a spring pin driven through the head and handle. The pin also passes through the steel wedge. In the current set of hammer heads, I have moved the hole for the pin up a bit so it passes through a thicker part of the wedge. In previous hammers the pin passes through the tip of the wedge and I fear that they may tear out. The only way the head can fly off is if the pin tears out through the wedge. This, I think, is a better connection than the tang/pin assembly usually used.
I think the handle breaking is more likely with the hammers I've made. Some of the wood handles I've bought aren't straight grained or have other defects. I've just ordered a slab of hickory from a guy and will mill some handles myself. I've only seen photos of the slab so will have to wait to see how nice it really is. I will warn everybody that the handles I plan to make may be a bit crude looking - perhaps rustic is a better description. Also, this set of heads hasn't been tempered quite as much and I don't know how that will work out.
My anti tang tendency is also influenced by my climbing partner Bob (cragnshag on ST). Bob somehow consistently manages to shear the tang pin on Yosemite hammers. Give him a brand new hammer and in a season the pin will be sheared off and the tangs splayed out. It is so bad that I wouldn't let him use my Yosemite hammer because he would wreck it. He is also the only guy I know that has had the head fly off his hammer on a climb. He and Clint were at Balloon Dome a couple years ago working on a new route when the head flew off his Yosemite hammer, bounced down the face and was never seen again.
I should get a hammer to you to try. I have a hammer I can send you if you get your address to me. It has a slight defect and nobody seems to want it. The defect is a small saw cut in the pick which shouldn't have any effect on it's performance. Hopefully postage half way round the planet won't be too bad.
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couchmaster
climber
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Looks like the nick would be an improved beer opener! You need to be charging EXTRA for extra features:-)
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deuce4
climber
Hobart, Australia
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We got our hickory handles from a company called OP Link, somewhere in the south.
Your design sounds sound. Would like to see the spring pin design. I will pm you.
Cheers
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