GWTW Forum
October 31, 2014, 12:32 PM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
News:
 
   Home   Help Forum Info Login Register Chat  
Welcome to the GWTW Forum.
Guests (non-registered users) can view the forum but are unable to post.  If you don't have anything to say then why would you bother to register?
One of the most popular sections of the GWTW Forum has long been the Swap Meet.  A great place to sell old, seldom flown kites or to get great deals on used (gently flown) kites.  Only registered users can see the Swap Meet section, let alone wheel and deal.  1000's (literally) of kites have changed hands thanks to the Swap Meet.
There are several more benefits to being a registered user, but you'll have to join our little community to find out all the "secrets".
Questions or concerns? Contact Steve ... just drop an email to: forum.gwtwkites@gmail.com

Pages: [1] 2   Go Down
  Print  
Author Topic: The Claw kite anchor  (Read 7037 times)
0 Members and 1 Guest are viewing this topic.
streamhawk
Trade Count: (0)
***
Offline Offline

Posts: 152


Location: NW AR

« on: February 22, 2010, 10:18 AM »

I've been looking for a more simple and secure way to tie down my bols and sleds, looks like a good tripod type anchor. Anyone use one of these yet? At 1200# load, looks like it could work just fine. Hope it's ok to post this link, if not, I'll remove...

http://www.creativeshelters.com/Canopy-Accessories/The-Claw-Anchor.aspx

Bill
Logged
chilese
Global Moderator
Trade Count: (+5)
*****
Offline Offline

Posts: 3092


Location: Las Vegas, NV

WWW
« Reply #1 on: February 22, 2010, 10:27 AM »

From the design (which I really like), the 1200 pound rating would apply ONLY to a vertical load.

A kite induced load at an angle would greatly reduce the pullout force as you would be generating a moment load on the stake furthest away from the kite while the 2 closer stakes wouldn't be resisting the pull much, they would merely be acting as a pivot line perpendicular to the string direction.

I would estimate the side load pullout to be 400 pounds, purely as a guess.

That's just the semi-retired engineer in me. I am open to others inputs on this. Been wrong many times throughout my life, so take your best shot.  Smiley
Logged

John Chilese: Las Vegas, NV
http://picasaweb.google.com/chilesej
thief
Moderator
Trade Count: (+25)
*****
Offline Offline

Posts: 3664


Location: North Shore of Massa-WHO-setts

WWW
« Reply #2 on: February 22, 2010, 10:30 AM »

oh boy would that be scary coming across the field!!!!!!

i would ask them about perpendicular forces......you would also have to find out which configuration would be best to have it in: with one foot pointing downwind towards the bol or with two legs pointing downwind.....

their duckbill one looks pretty good too....
Logged

Kites kayaks & corgis again!!!
mikenchico
Board Moderator
Trade Count: (0)
*****
Offline Offline

Posts: 2173


Location: ‪‪‪‪‪‎Chico, Ca

WWW
« Reply #3 on: February 22, 2010, 11:32 AM »

That duckbill system is interesting but how do you remove it once in? For a permenant installation it looks great. I don't think our parks dept would appreciate us leaving a bunch of stainless steel cables in the ground to foul up the mowers although it would be sweet for us  Wink

I might guess John's estimate a bit higher on the claw for use with a kite, especially if you put two legs upwind. A kites pull won't be at a 90 degree angle to verticle so some of the force will be still be transfered to the claw action attempting to pull the legs together and tightening its hold. With a Bol your force is much nearer to horizontal as John points out. In that case John is right and you would get nearly the same results just using two of the same size stakes.

Both are neat systems though, worth a bookmark.

Logged

"Living is easy with eyes closed, misunderstanding all you see" John W Lennon

"People do not quit playing because they grow old, they grow old because they quit playing" George Bernard Shaw
streamhawk
Trade Count: (0)
***
Offline Offline

Posts: 152


Location: NW AR

« Reply #4 on: February 22, 2010, 12:53 PM »

hmm, good points there, especially about horizontal load force. So, you guys think the anchor would work fairly well for a sled then, seems as though it would. I was about to pull the trigger on ordering a few of these, glad I brought it here first.

Bill
Logged
thief
Moderator
Trade Count: (+25)
*****
Offline Offline

Posts: 3664


Location: North Shore of Massa-WHO-setts

WWW
« Reply #5 on: February 22, 2010, 02:09 PM »

for that price get a couple,......cannot hurt...be good to use for an ezup at a fest...of to stake down a freshly planted tree too!
Logged

Kites kayaks & corgis again!!!
chilese
Global Moderator
Trade Count: (+5)
*****
Offline Offline

Posts: 3092


Location: Las Vegas, NV

WWW
« Reply #6 on: February 22, 2010, 02:20 PM »

I also wouldn't use this anchor system in sand ever.  Embarrassed
Logged

John Chilese: Las Vegas, NV
http://picasaweb.google.com/chilesej
streamhawk
Trade Count: (0)
***
Offline Offline

Posts: 152


Location: NW AR

« Reply #7 on: February 22, 2010, 02:48 PM »

I also wouldn't use this anchor system in sand ever.  Embarrassed

or in loose dirt type of ground either.

I have a smaller bol, a 10', I might try it with. I have a Premier 36, and will be getting a 81 later this month, not sure if the 81 would work with the Claw, but maybe the 36 would, at least when the wind isn't howling. I was thinking of even using a back up construction type stake behind it anyway, just to be safe.

Bill
Logged
mikenchico
Board Moderator
Trade Count: (0)
*****
Offline Offline

Posts: 2173


Location: ‪‪‪‪‪‎Chico, Ca

WWW
« Reply #8 on: February 22, 2010, 03:54 PM »

Well I hand hold our 81 and wiegh all of 165 lbs in my boots. I've also had it loosen two 24 inch cement form stakes in moist ground. Gotta use your best judgement.

Logged

"Living is easy with eyes closed, misunderstanding all you see" John W Lennon

"People do not quit playing because they grow old, they grow old because they quit playing" George Bernard Shaw
Kantaxel
Trade Count: (+14)
****
Offline Offline

Posts: 893


Location: Bothell, WA

« Reply #9 on: February 22, 2010, 06:54 PM »

I also wouldn't use this anchor system in sand ever.  Embarrassed

Do you think it would work in sand with longer stakes?   .......you know twice as long?
Logged

Kant Fly......might just as well buy!
Lee S
Trade Count: (+4)
***
Offline Offline

Posts: 262

Location:

« Reply #10 on: February 22, 2010, 07:06 PM »

SLKs have 2 aspects of flight that would worry me if I used something like that. Firstly, kite pull is roughly 45% from vertical, and secondly, it is seldom a single steady load. More often, kites are constantly vibrating and jerking the line, and that tends to loosen anchors. I've always leaned on the side of caution when anchoring on grass or dirt, and I use 3 ft, and sometimes 4 ft concrete form spikes, pounded in at roughly a 45% angle. If I have any doubts at all, I'll use 2 and even sometimes 3. Tie off to a nylon strap, then caribiner from that to my line. Failure of my anchor means a large sharp spike bouncing away down wind. Yikes!

Barry (whatakite on the forum) has some great ideas/inventions for anchors that he's shared over the years. You might give him (or, of course, David Gomberg) a shout.

Lee
Logged
mikenchico
Board Moderator
Trade Count: (0)
*****
Offline Offline

Posts: 2173


Location: ‪‪‪‪‪‎Chico, Ca

WWW
« Reply #11 on: February 22, 2010, 07:15 PM »

Nope, not in dry sand, even in wet sand it wouldn't approach the rated holding power. The Auger Anchors would be better in sand but they still won't hold a lot. A sand bag/anchor is still the easiest on the beach IMO. Bag is not a good description since they are hard to fill and harder to empty, a flat sheet with loops on the four corners to clip a caribiner through once you cover it (fill it) full of sand, you can give them some shape if you want, just leave a pretty open top so you can scoop sand out until it's light enough to dump.

Logged

"Living is easy with eyes closed, misunderstanding all you see" John W Lennon

"People do not quit playing because they grow old, they grow old because they quit playing" George Bernard Shaw
streamhawk
Trade Count: (0)
***
Offline Offline

Posts: 152


Location: NW AR

« Reply #12 on: February 23, 2010, 07:42 AM »

Well I hand hold our 81 and wiegh all of 165 lbs in my boots. I've also had it loosen two 24 inch cement form stakes in moist ground. Gotta use your best judgement.

Mike, you hand hold a 81??!! What you got, Popeye arms?   Huh

Bill
Logged
MtnFlyer
Trade Count: (+50)
***
Offline Offline

Posts: 496


Location: Steamboat Springs, CO

WWW
« Reply #13 on: February 23, 2010, 08:53 AM »

Well I hand hold our 81...
Mike, you hand hold a 81??!! What you got, Popeye arms?   Huh

I had the same thought, Mike. I've had mine up where I could barely hold it (granted, it was a good wind), and couldn't pull in enough slack without help for one more turn through the 'biner so it wouldn't slip.

As I read this yesterday, I was thinking I had just seen this very anchor over the weekend. Somewhere. But I couldn't find it. Last night it hit me that it was in the catalog from another kite store that we all use for reference (then buy from Steve  Wink ).

I figure the Claw might work in the right circumstances, just like all the other anchors we use - the right one at the right time and place: hard ground, soft ground, sand; hard pulling, medium pulling, soft pulling kites. Even the angle of pull (as John mentioned) and wind gusts (as Lee mentioned) will affect our anchor choice at a given time. DG has a great write-up on anchoring, and also the use of sand anchors, on his web site.

John, what do you think about the question posed about orientation of the Claw? Best with one leg directly toward the kite so you have 2 spikes above the pull for grip, and the pull (moment arm? that's too long ago) is further from the fulcrum giving less mechanical advantage?
Logged

Bob
streamhawk
Trade Count: (0)
***
Offline Offline

Posts: 152


Location: NW AR

« Reply #14 on: February 23, 2010, 09:15 AM »

Bob, that setup with one leg toward the kite and two opposed was what my pea-brain thought would work best, but I look forward to John's or anyone else's educated opinion on the matter.

Bill
Logged
Pages: [1] 2   Go Up
  Print  
 
Jump to:  


items purchased through the links below help support the forum

Cal Custom

Our forum is made possible by the good folks whose ads appear below and by the members of our community (PayPal donation button at bottom)
In case you missed it each ad is linked to the sponsors web site.  So please, take a moment and visit our sponsors sites as this forum wouldn't be possible with out them.
Interested in running an ad for your business or kiting event?  Contact Steve at advertise.gwtwkites@gmail.com for a quote.

kmacFab
kmacFab

Kite Classifieds Ad
Kite Classifieds

A Wind Of Change
A Wind Of Change

Kitebookie
Kitebookie.com

Untitled Document

Untitled Document
Untitled Document

A Wind Of Change
skyshark

Untitled Document
Untitled Document


Untitled Document
DOLLAR SHAVE CLUB

Support the GWTW Forum

Powered by MySQL Powered by PHP Powered by SMF 1.1.8 | SMF © 2006-2008, Simple Machines LLC
SimplePortal 2.2.1 © 2008-2009
Valid XHTML 1.0! Valid CSS!