TeeDee
2007-08-19, 18:01
I've tried almost all of the hammock suspension methods. All except the CC buckles.
Finally decided to do an analysis of the various methods which I know about and see how the methods compared.
For this analysis I have compared the following methods:
plain knot. The knot could be the Hennessy style lashing or a truckers hitch or whatever your favorite knot is that gets the job done. As I have noted below, the simple knot is used with tree huggers and a carabiner is optional. The carabiner adds a modicum of convenience at not having to thread the suspension line through the tree hugger end loops, rather just clip into the carabiner.
pros: nothing extra needed(when carabiner not used)
cons: can be difficult to learn and remember (especially for those of us getting on in years :biggrin: ) and tying knots is not always the easiest option.
carabiner hitch. This method uses a carabiner as a replacement for the loop in the trucker's hitch. This eliminates the rope-on-rope friction and abrasion that plagues the trucker's hitch. The carabiner, specifically the CAMP Nano wire carabiner, is designed to reduce such friction to a minimum, pulling on the rope when looped back through the carabiner still gives the 3:1 mechanical advantage and reduces the friction and hence abrasion to a minimum. I would like to say "eliminates", but that is not possible.
How to use the carabiner hitch:
Girth Hitch - first girth hitch one end of the carabiner to the suspension rope at a convenient place. If you have used a trucker's hitch, then place the carabiner where you would normally tie the loop of the trucker's hitch - think of the carabiner as replacing the loop of the trucker's hitch. Tie the girth hitch as follows: form a bight, double the bight back on the rope and pull the rope through the bight, clip the carabiner into the loop thus formed - instant girth hitch ( aka Larks head ). Simple, easy, efficient, quick and secure. Note: orient the carabiner on the girth hitch so that the hitch is on the small end of the carabiner, i.e., the opening for the wire gate is away from the girth hitch.. This will make clipping into the carabiner in subsequent steps much easier.
Loop through tree hugger/carabiner - from the first carabiner, run to the tree hugger and through the end loops or clip into the carabiner which is on the tree hugger loops if you are using one there.
back to 1st carabiner - from the tree hugger run back to the first carabiner, clip into the carabiner and pull tight, as tight as you want. Always remember that you are working with a 3:1 advantage now. The force you pull with becomes 3 times that force on the hammock or the hammock ridge line. I doubt that even with the 3:1 advantage that you will be able to break the ridge line.
Once you have the rope pulled as tight as you desire, the rope needs to be secured from slipping back. There are at least 2 ways to do this:
wraps - hold the rope and clip through the carabiner again. I find that I can pinch the rope pulled over the carabiner with my fingers to hold it in place. The rope is now wrapped totally around the end of the carabiner once. Repeat and clip the loose end through the carabiner 4 more times so that the rope is now wrapped around the end of the carabiner 4 times.
Tie a slipped half hitch, pulling a large bight through the half hitch. Using the bight of the first half hitch, tie a second half hitch. The hammock suspension is now tied and secured.
girth hitch - there are two methods for tying this second girth hitch:
threading - (thanks to oldguy52 for this):
back to the carabiner and go down through it and pull tight, pinch and hold the rope,
come out the bottom then back up and over the standing part, i.e., the part from the tree hugger,
then back under the carabiner and up through again,
Now back out to the standing part. This should end as a larks head knot.
looping -
clip into carabiner and pull tight, pinch and hold the rope,
pull down and under end of carabiner and then up and over the standing part, i.e., the rope from the tree hugger,
form a bight in the loose end, twist the bight 1/2 turn so that the loose end is under the working part, thus forming a loop of the bight,
clip loop formed in bight above into carabiner and pull tight. Girth hitch formed and holding.
Tie a slipped half hitch, pulling a large bight through the half hitch. Using the bight of the first half hitch, tie a second half hitch. The hammock suspension is now tied and secured.
pros: quick and simple to use. Provides a 3:1 mechanical advantage for those of us that like to really tighten our suspension and ridge line. Very secure, the carabiner is rated at 22 KN along the long axis used.
cons: like a trucker's hitch uses more suspension rope. The amount used depends on the placement of the carabiner.
Ring on tree hugger. - this method uses an SMC descending ring on the ends of the tree huggers instead of a carabiner. This reduces the weight from the carabiner by 0.6 oz and assumes that the tree hugger loops are big enough for the ring to pass through the loop (or at least the loop on one end). To use the ring on the tree hugger proceed as follows: girth hitch the ring to one end of the tree hugger ( the easy way to do this is to push the loop through the ring, open the loop and pass it around the outside of the ring - girth hitch done), wrap the tree hugger around the tree one or more times, then girth hitch the second end to the ring again (same way as before).
ring version of carabiner hitch - this method replaces the carabiner of the carabiner hitch with an SMC descending ring. Otherwise this method is identical to the carabiner hitch, but lighter for those desiring as light a solution as possible.
pros: quick and simple to use. Provides a 3:1 mechanical advantage for those of us that like to really tighten our suspension and ridge line. Lighter than the carabiner hitch. Very secure, the SMC descending ring is rated at 14 KN.
cons: like a trucker's hitch uses more suspension rope. The amount used depends on the placement of the ring. Requires threading the ring as opposed to clipping with the carabiner hitch.
ring buckle. This method was "discovered" at the same time and independently by myself and a guy posting on the Yahoo hammock groups (don't know his name). The buckle utilizes two SMC descending rings. Any ring with a high enough rating and proper inner diameter could be used, but the SMC rings at 0.4 oz each are the lightest of which I know. They are pretty inexpensive also.
pros: quick and simple to use
cons: slipping of the webbing through the rings can be a problem. usually alleviated by tying a slipped half hitch after threading the buckle and pulling tight.
zig zag cleat. This method was first introduced by ALHikerGal on the hammock forums. It uses a marine zig zag cleat made of nylon. The rating on the cleat is fairly low, but the forces are largely canceled by the method in which the cleat is used. The largest forces left are shear forces and experience indicates that the cleat is able to handle the forces okay. The lowest price I could find for the cleats is at Cabela's (http://www.cabelas.com/cabelas/en/templates/links/link.jsp?id=0001551018030a&type=product&cmCat=search&returnPage=search-results1.jsp&QueryText=cleat&N=4887&Ntk=Products&Ntx=mode+matchall&Nty=1&Ntt=cleat&noImage=0).
pros: quick and simple to use
cons: the cleat is heavier than rings, but the cleat system is lighter by far.
CC buckle. The method uses a buckle used in the Crazy Creek hammocks, hence the name. Just Jeff is the first that I know to use the CC buckle on a hammock other than the Crazy Creek hammock.
pros: quick and simple to use
cons: slightly heavier than the ring buckle but lighter than the cleat. At least one person reported having to cut the webbing to loosen the buckle. This may be a problem for hammocks using a structural ridge line, but most that use it seem to be doing okay.
Hitchcraft Rope Tie. This method uses a device invented recently and marketed on the Hitch Craft (http://www.hitchcraft.net/) web site. I have used this method, but it requires a suspension rope with a minimum diameter of 0.25". Unfortunately the popular HH ULBA hammock suspension line is approximately half that diameter. The Hitchcraft Rope Tie comes in 2 sizes, mini and Monster. Some people have reported using the mini rope tie. I tried one using 1/8" diameter rope and can attest to the fact that it will not work for me on that diameter suspension rope. The 1/8" diameter suspension rope ripped through the mini and burned out a channel at the bottom of the cleat. In my correspondence with the inventor he warned about concentrated forces using small diameter rope. He was right.
pros: quick and simple to use. Has other uses in camp where a device for tightening rope is needed and like the Figure 9 device it gives a 3 to 1 advantage when rigged properly.
cons: The mid-range weight device of the methods analyzed. The mini weighs 0.9 oz which is 0.1 oz heavier than a single ring buckle and the Monster weighs 2.9 oz which is far heavier than any other device examined here.
The ground rules for my analysis:
Hammock Size. I assumed a hammock the same size as the HH ULBA with a length from end to end of 100" (8' 4"). If you use another hammock the weight comparison is still valid, but you would have to substitute your hammock length for the tree separation analysis. I used the HH ULBA because Hennessy makes a standard size in that model and it appears to be a popular hammock.
Suspension Line. I assumed the use of the New England Spyderline, 2.8 mm diameter for the suspension rope. Weight: 0.064 oz/foot. I have assumed that 10' of suspension line is utilized for the knot, cleat and HitchCraft Rope Tie methods. Weight: 0.64 oz per end.
Whipping. Since the amount of rope used for the whipping is assumed to be the same for all hammocks, the weight of the whipping was not considered.
Buckle weights:
Ring Buckle: 2 rings, 0.4 oz each, 0.8 oz total
CC Buckle: 1.0 oz each
Buckle attachment. For the Ring buckle and the CC buckle I have asumed that the buckle is attached to the hammock at a distance of 1' from the hammock end and that 1' of line is used to attach the buckle. Thus, 2' of line in total is used for attaching the buckle. Weight: 0.128 oz each end.
Carabiner. I have assumed that a carabiner is used with both the Ring buckle and the CC buckle. I have also assumed that a carabiner may be used with a tree hugger. For use with the tree hugger, the tree hugger is wrapped around the tree and the carabiner clipped into both end loops. The hammock suspension rope is then tied to the carabiner when it is used. I have found that either a round turn and 2 half hitches or a truckers hitch can be used. The Truckers Hitch (http://www.animatedknots.com/truckers/index.php?LogoImage=LogoGrog.jpg&Website=www.animatedknots.com) has a 3 to 1 advantage in pulling the suspension line taut and thus may be preferred by those who like to pull the structural ridge line tight. The Trucker's hitch has the disadvantage of needing more line to tie than the round turn and two half hitches. I have assumed the use of the CAMP Nano wire carabiner as the lightest available with a sufficient rating to be used in the hammock suspension. Weight: 1 oz.
Tree huggers. For the methods that use tree huggers I have assumed 42" of 1" wide polyester webbing. I have assumed 42" for the simple reason that 42" is the length of the standard tree hugger sold by Hennessy. That is a sufficient length for a tree with a 15" diameter if using the Hennessy lashing or something similar. It is sufficient for a 13" diameter if using a carabiner. The webbing is the 1" wide polyester webbing sold by Harbor Freight in their ratchet straps and rated at 1,500 lbsf. Weight: 0.224 oz/foot, 0.78 oz per tree hugger.
Webbing. I have assumed that 10' of 1" wide polyester webbing is used with both the Ring buckle and the CC buckle. The webbing is the same as that I have assumed for the tree huggers. Weight: 0.224 oz/foot, 2.24 oz per hammock end. The webbing is by far the heaviest single component of any of the suspension methods analyzed. The polypropylene webbing sold by Ed Speers is slightly lighter at 0.208 oz/ft, but the rating of the polypropylene webbing is given by Ed as 700 lbs. The polyester webbing I obtained from the Harbor Freight ratchet straps and is rated at 1500 lbs. I prefer the polyester webbing and so used it in this comparison.
HitchCraft Rope Tie. I have examined the Mini rope tie only and I have assumed using the 4.8 mm New England Spyderline at 0.208 oz/ft.
Weight Comparison: (Note: the weights are for one end of the hammock. The weight for both ends is shown in parenthesis.)
Knot - no carabiner or ring
10' line: 0.64 oz
Tree Hugger: 0.78 oz
Total: 1.42 oz ( 2.84 oz )
knot w/ring
10' line: 0.64 oz
Tree Hugger: 0.78 oz
ring: 0.4 oz
Total: 1.82 oz ( 3.64 oz )
Knot w/carabiner
10' line: 0.64 oz
Tree Hugger: 0.78 oz
Carabiner: 1 oz
Total: 2.42 oz ( 4.84 oz )
Ring version of the Carabiner hitch w/ring on tree hugger
10' line: 0.64 oz
SMC descending ring, 2: 0.8 oz
tree hugger: 0.78 oz
Total: 2.22 oz ( 4.44 oz )
Ring version of the Carabiner hitch w/carabiner on tree hugger
10' line: 0.64 oz
SMC descending ring, 1: 0.4 oz
carabiner: 1.0 oz
tree hugger: 0.78 oz
Total: 2.82 oz ( 5.64 oz )
Carabiner hitch
10' line: 0.64 oz
carabiner, 2: 2.0 oz
tree hugger: 0.78 oz
Total: 3.42 oz ( 6.84 oz )
zig zag cleat
10' line: 0.64 oz
cleat: 1.25 oz
carabiner: 1.0 oz
tree hugger: 0.78 oz
Total: 3.67 oz ( 7.34 oz )
Ring Buckle
2' suspension line: 0.128 oz
2 rings @ 0.4 oz each: 0.8 oz
10' of 1" wide polyester webbing: 2.24 oz
1 carabiner: 1.0 oz
Total: 4.168 oz ( 8.336 oz )
HitchCraft Rope Tie - mini
10' line: 2.08 oz
Rope Tie: 0.9 oz
carabiner: 1.0 oz
tree hugger: 0.78 oz
Total: 4.76 oz ( 9.52 oz )
CC Buckle
2' suspension line: 0.128 oz
1 CC buckle: 1.0 oz
10' of 1" wide polyester webbing: 2.24 oz
1 carabiner: 1.0 oz
Total: 4.368 oz ( 8.736 oz )
Summary: Ranking by weight (Total suspension weight listed)
simple knot - no carabiner or ring: 2.84 oz
simple knot w/ring: 3.64 oz
ring version of carabiner hitch w/ring on tree hugger: 4.44 oz
simple knot w/carabiner: 4.84 oz
ring version of carabiner hitch: 5.64 oz
carabiner hitch: 6.84 oz
zig zag cleat: 7.34 oz
Ring Buckle: 8.336 oz
CC Buckle: 8.736 oz
HitchCraft Mini Rope Tie: 9.52 oz
The simple knot method with or without a carabiner is by far the lightest option available and the CC Buckle and Rope Tie methods being the heaviest suspension methods examined. There are other variations not listed here, e.g., ring version of carabiner hitch with no carabiner on the tree hugger. This method comes in lighter than the plain knot with a carabiner on the tree hugger.
As soon as a buckle and webbing is used the weight jumps dramatically due to the high weight of the webbing. The webbing that is used for either buckle is the heaviest component of any suspension.
In essence the webbing offers a lot of convenience, but the weight penalty is high also.
Also, I have found that the carabiner hitch is just as easy and convenient to use as the double ring buckle and the carabiner hitch doesn't carry, pun intended, the weight penalty of the webbing.
I have pretty much come full circle. I started with the Hennessy lashing and got frustrated with the lashing pretty quickly. It was and is frustrating to wrap the lashing and then have to undo all of the wraps to center the hammock between the trees and then re-do again to re-tighten the suspension after things have stretched out a bit.
I went from the simple knot to webbing and cam locking buckles for the sake of convenience and then to the ring buckles to save weight over the cam buckles and because I couldn't find a reliable rating for the cam buckles. At the time I thought nothing of the weight, i.e., I just didn't take the time to figure how much that system weighed. After carrying it too many times, I decided to figure out just how much the weight penalty really is. I was really surprised by just how much webbing really weighs.
2.88 mm Spyderline: 0.064 oz/ft, 1,200 lbsf breaking strength
1" polyester webbing: 0.223 oz/ft, 1,500 lbsf breaking strength
The webbing is 3.5 times heavier than the Spyderline for almost equivalent breaking strengths. Of course we are using very different materials, polyester webbing versus Dyneema. Dyneema is noted for it's light weight and high strength.
So what have I learned from this?
I am dropping the use of all suspension devices except carabiners and/or rings and the only webbing I will be using is the tree huggers. At 0.78 oz each, 1.56 oz total, I can manage and spare the trees when needed.
I have switched totally to my Bridge Hammock. My suspension is now configured as follows:
Bridge suspension lines to a single SMC descending ring. 10' of New England 2.8 mm Spyderline. I use the Carabiner hitch described above. I like pulling my suspension really tight and like the 3:1 mechanical advantage afforded by this method.
I have reduced the weight carried in the hammock suspension from 8.336 oz to 6.84 oz or 5.64 if I decide to use the ring version of the carabiner hitch.
Tree Separation.
Spyderline suspension. With 10' of Spyderline and 100" end to end for the hammock and allowing 2' of line for either a Hennessy lashing or Trucker's hitch, that leaves 8' on both ends for spanning the distance from hammock to trees. That allows a maximum tree separation of approximately 24'. The minimum separation would be approximately 10' 6" assuming that a round turn and 2 half hitches was used on one end and a trucker's hitch on the other end. This assumes that the tree huggers are sufficient to handle the tree diameter. For an additional 1.56 oz., tree diameters up to 26" could be accommodated. Note that the tree diameter that can be accommodated is dependent only on the length of the available tree huggers and is independent of the length of the suspension rope.
Webbing suspension. With 10' of webbing, a tree diameter of 1' will use slightly over 3', 3' 1.7" more exactly, of the suspension webbing to circumnavigate the tree. That leaves 7' for threading the buckle and whatever is needed to grasp and pull the suspension tight. Assuming 1' is needed to thread the buckle and provide enough to grasp, that leaves 6' of webbing on each end for spanning the distance to the trees. With distance from buckle to buckle of 10' 4", a maximum tree separation of about 22' could be accommodated. If the diameter of both trees was increased to the 26" that could be accommodated by doubled tree huggers, then 6.8' of the webbing would be used to circumnavigate the trees, leaving 3.2'. Again assuming the 1' for threading and grasping, we have 2.2' of available webbing. That means that the maximum tree separation in this case would be about 14.5'. The minimum tree separation would be approximately 12.5' assuming that 1' would be needed between the buckle and the tree in which to work the buckle. Unfortunately, with the buckle system, the webbing is used not only to span the tree separation, but also to circumnavigate the trees themselves. This demands more webbing adding to the weight penalty. The bigger the trees, the more webbing would be needed and hence the greater the weight penalty. A unit (unit being an inch, a foot, a meter, etc) increase in the tree diameter, requires 3 times as much webbing to compensate, thus increasing the weight penalty by a factor of 3. The weight penalty is actually increased by a factor of 3 times 3.5 or 10.5 over the weight necessary for any method not using webbing for the suspension. This assumes that the needed tree separation for each method is the same. So for each oz needed with tree huggers and suspension ropes, 10.5 oz more is needed for the webbing suspension.
Conclusion, the use of the buckles and webbing suspension incurs a much magnified weight penalty if you are going into a region with large trees and must be able to accommodate the same tree separation as would be needed for a rope suspension. A 10.5 to 1 weight penalty.
Finally decided to do an analysis of the various methods which I know about and see how the methods compared.
For this analysis I have compared the following methods:
plain knot. The knot could be the Hennessy style lashing or a truckers hitch or whatever your favorite knot is that gets the job done. As I have noted below, the simple knot is used with tree huggers and a carabiner is optional. The carabiner adds a modicum of convenience at not having to thread the suspension line through the tree hugger end loops, rather just clip into the carabiner.
pros: nothing extra needed(when carabiner not used)
cons: can be difficult to learn and remember (especially for those of us getting on in years :biggrin: ) and tying knots is not always the easiest option.
carabiner hitch. This method uses a carabiner as a replacement for the loop in the trucker's hitch. This eliminates the rope-on-rope friction and abrasion that plagues the trucker's hitch. The carabiner, specifically the CAMP Nano wire carabiner, is designed to reduce such friction to a minimum, pulling on the rope when looped back through the carabiner still gives the 3:1 mechanical advantage and reduces the friction and hence abrasion to a minimum. I would like to say "eliminates", but that is not possible.
How to use the carabiner hitch:
Girth Hitch - first girth hitch one end of the carabiner to the suspension rope at a convenient place. If you have used a trucker's hitch, then place the carabiner where you would normally tie the loop of the trucker's hitch - think of the carabiner as replacing the loop of the trucker's hitch. Tie the girth hitch as follows: form a bight, double the bight back on the rope and pull the rope through the bight, clip the carabiner into the loop thus formed - instant girth hitch ( aka Larks head ). Simple, easy, efficient, quick and secure. Note: orient the carabiner on the girth hitch so that the hitch is on the small end of the carabiner, i.e., the opening for the wire gate is away from the girth hitch.. This will make clipping into the carabiner in subsequent steps much easier.
Loop through tree hugger/carabiner - from the first carabiner, run to the tree hugger and through the end loops or clip into the carabiner which is on the tree hugger loops if you are using one there.
back to 1st carabiner - from the tree hugger run back to the first carabiner, clip into the carabiner and pull tight, as tight as you want. Always remember that you are working with a 3:1 advantage now. The force you pull with becomes 3 times that force on the hammock or the hammock ridge line. I doubt that even with the 3:1 advantage that you will be able to break the ridge line.
Once you have the rope pulled as tight as you desire, the rope needs to be secured from slipping back. There are at least 2 ways to do this:
wraps - hold the rope and clip through the carabiner again. I find that I can pinch the rope pulled over the carabiner with my fingers to hold it in place. The rope is now wrapped totally around the end of the carabiner once. Repeat and clip the loose end through the carabiner 4 more times so that the rope is now wrapped around the end of the carabiner 4 times.
Tie a slipped half hitch, pulling a large bight through the half hitch. Using the bight of the first half hitch, tie a second half hitch. The hammock suspension is now tied and secured.
girth hitch - there are two methods for tying this second girth hitch:
threading - (thanks to oldguy52 for this):
back to the carabiner and go down through it and pull tight, pinch and hold the rope,
come out the bottom then back up and over the standing part, i.e., the part from the tree hugger,
then back under the carabiner and up through again,
Now back out to the standing part. This should end as a larks head knot.
looping -
clip into carabiner and pull tight, pinch and hold the rope,
pull down and under end of carabiner and then up and over the standing part, i.e., the rope from the tree hugger,
form a bight in the loose end, twist the bight 1/2 turn so that the loose end is under the working part, thus forming a loop of the bight,
clip loop formed in bight above into carabiner and pull tight. Girth hitch formed and holding.
Tie a slipped half hitch, pulling a large bight through the half hitch. Using the bight of the first half hitch, tie a second half hitch. The hammock suspension is now tied and secured.
pros: quick and simple to use. Provides a 3:1 mechanical advantage for those of us that like to really tighten our suspension and ridge line. Very secure, the carabiner is rated at 22 KN along the long axis used.
cons: like a trucker's hitch uses more suspension rope. The amount used depends on the placement of the carabiner.
Ring on tree hugger. - this method uses an SMC descending ring on the ends of the tree huggers instead of a carabiner. This reduces the weight from the carabiner by 0.6 oz and assumes that the tree hugger loops are big enough for the ring to pass through the loop (or at least the loop on one end). To use the ring on the tree hugger proceed as follows: girth hitch the ring to one end of the tree hugger ( the easy way to do this is to push the loop through the ring, open the loop and pass it around the outside of the ring - girth hitch done), wrap the tree hugger around the tree one or more times, then girth hitch the second end to the ring again (same way as before).
ring version of carabiner hitch - this method replaces the carabiner of the carabiner hitch with an SMC descending ring. Otherwise this method is identical to the carabiner hitch, but lighter for those desiring as light a solution as possible.
pros: quick and simple to use. Provides a 3:1 mechanical advantage for those of us that like to really tighten our suspension and ridge line. Lighter than the carabiner hitch. Very secure, the SMC descending ring is rated at 14 KN.
cons: like a trucker's hitch uses more suspension rope. The amount used depends on the placement of the ring. Requires threading the ring as opposed to clipping with the carabiner hitch.
ring buckle. This method was "discovered" at the same time and independently by myself and a guy posting on the Yahoo hammock groups (don't know his name). The buckle utilizes two SMC descending rings. Any ring with a high enough rating and proper inner diameter could be used, but the SMC rings at 0.4 oz each are the lightest of which I know. They are pretty inexpensive also.
pros: quick and simple to use
cons: slipping of the webbing through the rings can be a problem. usually alleviated by tying a slipped half hitch after threading the buckle and pulling tight.
zig zag cleat. This method was first introduced by ALHikerGal on the hammock forums. It uses a marine zig zag cleat made of nylon. The rating on the cleat is fairly low, but the forces are largely canceled by the method in which the cleat is used. The largest forces left are shear forces and experience indicates that the cleat is able to handle the forces okay. The lowest price I could find for the cleats is at Cabela's (http://www.cabelas.com/cabelas/en/templates/links/link.jsp?id=0001551018030a&type=product&cmCat=search&returnPage=search-results1.jsp&QueryText=cleat&N=4887&Ntk=Products&Ntx=mode+matchall&Nty=1&Ntt=cleat&noImage=0).
pros: quick and simple to use
cons: the cleat is heavier than rings, but the cleat system is lighter by far.
CC buckle. The method uses a buckle used in the Crazy Creek hammocks, hence the name. Just Jeff is the first that I know to use the CC buckle on a hammock other than the Crazy Creek hammock.
pros: quick and simple to use
cons: slightly heavier than the ring buckle but lighter than the cleat. At least one person reported having to cut the webbing to loosen the buckle. This may be a problem for hammocks using a structural ridge line, but most that use it seem to be doing okay.
Hitchcraft Rope Tie. This method uses a device invented recently and marketed on the Hitch Craft (http://www.hitchcraft.net/) web site. I have used this method, but it requires a suspension rope with a minimum diameter of 0.25". Unfortunately the popular HH ULBA hammock suspension line is approximately half that diameter. The Hitchcraft Rope Tie comes in 2 sizes, mini and Monster. Some people have reported using the mini rope tie. I tried one using 1/8" diameter rope and can attest to the fact that it will not work for me on that diameter suspension rope. The 1/8" diameter suspension rope ripped through the mini and burned out a channel at the bottom of the cleat. In my correspondence with the inventor he warned about concentrated forces using small diameter rope. He was right.
pros: quick and simple to use. Has other uses in camp where a device for tightening rope is needed and like the Figure 9 device it gives a 3 to 1 advantage when rigged properly.
cons: The mid-range weight device of the methods analyzed. The mini weighs 0.9 oz which is 0.1 oz heavier than a single ring buckle and the Monster weighs 2.9 oz which is far heavier than any other device examined here.
The ground rules for my analysis:
Hammock Size. I assumed a hammock the same size as the HH ULBA with a length from end to end of 100" (8' 4"). If you use another hammock the weight comparison is still valid, but you would have to substitute your hammock length for the tree separation analysis. I used the HH ULBA because Hennessy makes a standard size in that model and it appears to be a popular hammock.
Suspension Line. I assumed the use of the New England Spyderline, 2.8 mm diameter for the suspension rope. Weight: 0.064 oz/foot. I have assumed that 10' of suspension line is utilized for the knot, cleat and HitchCraft Rope Tie methods. Weight: 0.64 oz per end.
Whipping. Since the amount of rope used for the whipping is assumed to be the same for all hammocks, the weight of the whipping was not considered.
Buckle weights:
Ring Buckle: 2 rings, 0.4 oz each, 0.8 oz total
CC Buckle: 1.0 oz each
Buckle attachment. For the Ring buckle and the CC buckle I have asumed that the buckle is attached to the hammock at a distance of 1' from the hammock end and that 1' of line is used to attach the buckle. Thus, 2' of line in total is used for attaching the buckle. Weight: 0.128 oz each end.
Carabiner. I have assumed that a carabiner is used with both the Ring buckle and the CC buckle. I have also assumed that a carabiner may be used with a tree hugger. For use with the tree hugger, the tree hugger is wrapped around the tree and the carabiner clipped into both end loops. The hammock suspension rope is then tied to the carabiner when it is used. I have found that either a round turn and 2 half hitches or a truckers hitch can be used. The Truckers Hitch (http://www.animatedknots.com/truckers/index.php?LogoImage=LogoGrog.jpg&Website=www.animatedknots.com) has a 3 to 1 advantage in pulling the suspension line taut and thus may be preferred by those who like to pull the structural ridge line tight. The Trucker's hitch has the disadvantage of needing more line to tie than the round turn and two half hitches. I have assumed the use of the CAMP Nano wire carabiner as the lightest available with a sufficient rating to be used in the hammock suspension. Weight: 1 oz.
Tree huggers. For the methods that use tree huggers I have assumed 42" of 1" wide polyester webbing. I have assumed 42" for the simple reason that 42" is the length of the standard tree hugger sold by Hennessy. That is a sufficient length for a tree with a 15" diameter if using the Hennessy lashing or something similar. It is sufficient for a 13" diameter if using a carabiner. The webbing is the 1" wide polyester webbing sold by Harbor Freight in their ratchet straps and rated at 1,500 lbsf. Weight: 0.224 oz/foot, 0.78 oz per tree hugger.
Webbing. I have assumed that 10' of 1" wide polyester webbing is used with both the Ring buckle and the CC buckle. The webbing is the same as that I have assumed for the tree huggers. Weight: 0.224 oz/foot, 2.24 oz per hammock end. The webbing is by far the heaviest single component of any of the suspension methods analyzed. The polypropylene webbing sold by Ed Speers is slightly lighter at 0.208 oz/ft, but the rating of the polypropylene webbing is given by Ed as 700 lbs. The polyester webbing I obtained from the Harbor Freight ratchet straps and is rated at 1500 lbs. I prefer the polyester webbing and so used it in this comparison.
HitchCraft Rope Tie. I have examined the Mini rope tie only and I have assumed using the 4.8 mm New England Spyderline at 0.208 oz/ft.
Weight Comparison: (Note: the weights are for one end of the hammock. The weight for both ends is shown in parenthesis.)
Knot - no carabiner or ring
10' line: 0.64 oz
Tree Hugger: 0.78 oz
Total: 1.42 oz ( 2.84 oz )
knot w/ring
10' line: 0.64 oz
Tree Hugger: 0.78 oz
ring: 0.4 oz
Total: 1.82 oz ( 3.64 oz )
Knot w/carabiner
10' line: 0.64 oz
Tree Hugger: 0.78 oz
Carabiner: 1 oz
Total: 2.42 oz ( 4.84 oz )
Ring version of the Carabiner hitch w/ring on tree hugger
10' line: 0.64 oz
SMC descending ring, 2: 0.8 oz
tree hugger: 0.78 oz
Total: 2.22 oz ( 4.44 oz )
Ring version of the Carabiner hitch w/carabiner on tree hugger
10' line: 0.64 oz
SMC descending ring, 1: 0.4 oz
carabiner: 1.0 oz
tree hugger: 0.78 oz
Total: 2.82 oz ( 5.64 oz )
Carabiner hitch
10' line: 0.64 oz
carabiner, 2: 2.0 oz
tree hugger: 0.78 oz
Total: 3.42 oz ( 6.84 oz )
zig zag cleat
10' line: 0.64 oz
cleat: 1.25 oz
carabiner: 1.0 oz
tree hugger: 0.78 oz
Total: 3.67 oz ( 7.34 oz )
Ring Buckle
2' suspension line: 0.128 oz
2 rings @ 0.4 oz each: 0.8 oz
10' of 1" wide polyester webbing: 2.24 oz
1 carabiner: 1.0 oz
Total: 4.168 oz ( 8.336 oz )
HitchCraft Rope Tie - mini
10' line: 2.08 oz
Rope Tie: 0.9 oz
carabiner: 1.0 oz
tree hugger: 0.78 oz
Total: 4.76 oz ( 9.52 oz )
CC Buckle
2' suspension line: 0.128 oz
1 CC buckle: 1.0 oz
10' of 1" wide polyester webbing: 2.24 oz
1 carabiner: 1.0 oz
Total: 4.368 oz ( 8.736 oz )
Summary: Ranking by weight (Total suspension weight listed)
simple knot - no carabiner or ring: 2.84 oz
simple knot w/ring: 3.64 oz
ring version of carabiner hitch w/ring on tree hugger: 4.44 oz
simple knot w/carabiner: 4.84 oz
ring version of carabiner hitch: 5.64 oz
carabiner hitch: 6.84 oz
zig zag cleat: 7.34 oz
Ring Buckle: 8.336 oz
CC Buckle: 8.736 oz
HitchCraft Mini Rope Tie: 9.52 oz
The simple knot method with or without a carabiner is by far the lightest option available and the CC Buckle and Rope Tie methods being the heaviest suspension methods examined. There are other variations not listed here, e.g., ring version of carabiner hitch with no carabiner on the tree hugger. This method comes in lighter than the plain knot with a carabiner on the tree hugger.
As soon as a buckle and webbing is used the weight jumps dramatically due to the high weight of the webbing. The webbing that is used for either buckle is the heaviest component of any suspension.
In essence the webbing offers a lot of convenience, but the weight penalty is high also.
Also, I have found that the carabiner hitch is just as easy and convenient to use as the double ring buckle and the carabiner hitch doesn't carry, pun intended, the weight penalty of the webbing.
I have pretty much come full circle. I started with the Hennessy lashing and got frustrated with the lashing pretty quickly. It was and is frustrating to wrap the lashing and then have to undo all of the wraps to center the hammock between the trees and then re-do again to re-tighten the suspension after things have stretched out a bit.
I went from the simple knot to webbing and cam locking buckles for the sake of convenience and then to the ring buckles to save weight over the cam buckles and because I couldn't find a reliable rating for the cam buckles. At the time I thought nothing of the weight, i.e., I just didn't take the time to figure how much that system weighed. After carrying it too many times, I decided to figure out just how much the weight penalty really is. I was really surprised by just how much webbing really weighs.
2.88 mm Spyderline: 0.064 oz/ft, 1,200 lbsf breaking strength
1" polyester webbing: 0.223 oz/ft, 1,500 lbsf breaking strength
The webbing is 3.5 times heavier than the Spyderline for almost equivalent breaking strengths. Of course we are using very different materials, polyester webbing versus Dyneema. Dyneema is noted for it's light weight and high strength.
So what have I learned from this?
I am dropping the use of all suspension devices except carabiners and/or rings and the only webbing I will be using is the tree huggers. At 0.78 oz each, 1.56 oz total, I can manage and spare the trees when needed.
I have switched totally to my Bridge Hammock. My suspension is now configured as follows:
Bridge suspension lines to a single SMC descending ring. 10' of New England 2.8 mm Spyderline. I use the Carabiner hitch described above. I like pulling my suspension really tight and like the 3:1 mechanical advantage afforded by this method.
I have reduced the weight carried in the hammock suspension from 8.336 oz to 6.84 oz or 5.64 if I decide to use the ring version of the carabiner hitch.
Tree Separation.
Spyderline suspension. With 10' of Spyderline and 100" end to end for the hammock and allowing 2' of line for either a Hennessy lashing or Trucker's hitch, that leaves 8' on both ends for spanning the distance from hammock to trees. That allows a maximum tree separation of approximately 24'. The minimum separation would be approximately 10' 6" assuming that a round turn and 2 half hitches was used on one end and a trucker's hitch on the other end. This assumes that the tree huggers are sufficient to handle the tree diameter. For an additional 1.56 oz., tree diameters up to 26" could be accommodated. Note that the tree diameter that can be accommodated is dependent only on the length of the available tree huggers and is independent of the length of the suspension rope.
Webbing suspension. With 10' of webbing, a tree diameter of 1' will use slightly over 3', 3' 1.7" more exactly, of the suspension webbing to circumnavigate the tree. That leaves 7' for threading the buckle and whatever is needed to grasp and pull the suspension tight. Assuming 1' is needed to thread the buckle and provide enough to grasp, that leaves 6' of webbing on each end for spanning the distance to the trees. With distance from buckle to buckle of 10' 4", a maximum tree separation of about 22' could be accommodated. If the diameter of both trees was increased to the 26" that could be accommodated by doubled tree huggers, then 6.8' of the webbing would be used to circumnavigate the trees, leaving 3.2'. Again assuming the 1' for threading and grasping, we have 2.2' of available webbing. That means that the maximum tree separation in this case would be about 14.5'. The minimum tree separation would be approximately 12.5' assuming that 1' would be needed between the buckle and the tree in which to work the buckle. Unfortunately, with the buckle system, the webbing is used not only to span the tree separation, but also to circumnavigate the trees themselves. This demands more webbing adding to the weight penalty. The bigger the trees, the more webbing would be needed and hence the greater the weight penalty. A unit (unit being an inch, a foot, a meter, etc) increase in the tree diameter, requires 3 times as much webbing to compensate, thus increasing the weight penalty by a factor of 3. The weight penalty is actually increased by a factor of 3 times 3.5 or 10.5 over the weight necessary for any method not using webbing for the suspension. This assumes that the needed tree separation for each method is the same. So for each oz needed with tree huggers and suspension ropes, 10.5 oz more is needed for the webbing suspension.
Conclusion, the use of the buckles and webbing suspension incurs a much magnified weight penalty if you are going into a region with large trees and must be able to accommodate the same tree separation as would be needed for a rope suspension. A 10.5 to 1 weight penalty.