Hang Calculator : 30 degree and 83%

**Hammock.JJ** · 08-03-2024, 07:47

I have been deep diving into the hammock world for a few months. I have bought a few, DIY'd a couple, and had a larkshead dump my head end in the middle of the night. :-)

I will get into solo hammock camping later when my girls are older....we tent camp together now.

Anyway...I have been doing all my tinkering/sleeping in my living room. I used the ultimate hang calculator for my initial setup. I have strong eye bolts screwed into studs. Based on the hang calculator, 14.5 length between eye bolts, 11.5 length hammock( la siesta carolina columbian), 160 weight(me). For an 18 in. Sit height, it told me to put my eye bolts at 5.7 ft., so I did.

It looks about 30 degrees and my suspension lengths pretty closely match the calculator. I have the foot end suspension 1 ft. Shorter, as recommended, since I didn't hear the foot end higher recommendation until after my eye bolts were in. :-)

Using the hang calculator, my natural ridgeline is about 126 in.( hammock measured where a ridgeline would be). 83% would be a ridgeline of about 115.

The 30 degree suggestion and the 83% ridgeline suggestions don't really work together for me. Am I missing something? If I add a ridgeline, it is very tight, and changes my suspension angle.

I have a million more things to say and ask :-) I'll introduce myself in the introduction section.

Photo attached.

Thanks,
JJ
DIY Gathered End Fail
La Siesta Carolina Sleeper.

**Hammock.JJ** · 08-03-2024, 07:51

Another pic

**Hammock.JJ** · 08-03-2024, 07:54

Here is one more...

**Cruiser51** · 08-03-2024, 10:21

The purpose of the Calculators in general, is just to get you in the ballpark of what will work for you. So you invariably will need to tinker some to get it where it is good for you. Also consider that some folks can sleep on a rock and others are somewhat more fussy ... which is why the motto here is HYOH.

If that ridgeline is structural (takes the ridge load and makes the hammock angle based on its length) it will get tight. If you are just using the ridgeline for hanging stuff (netting, organizers etc) it gets taunt (still able to bend with hands)), not tight (not able to bend with hands).

Now to complicate things a bit, it's my understanding that that "recommended" hang angle is when the hammock is under load. So setting a 30 degree angle will likely get you around 35 degrees with you on board (probably why your ridgeline gets tight IMO). To make this even more fun, since the load is shifted to the head end (top half of body has the largest portion of body mass) the head end and foot end of the hammock don't get the same weight distribution (just in the hammock) ... so while the suspension gets the same load, at either end, the angles aren't usually the same. Having said this about the angles and the impact of loading the hammock on the angles, it is just information to help understand that static angles (unloaded) change the minute you get in the hammock.

The easiest way I've found to check angles, is using a smart phone to just measure the angles, the IPhone has a built in spirit level that works well and I am sure there is an equivalent for android users. Since you are going to be experimenting a bit, I would strongly recommend you makes some notes of the things you try and the stuff you figure out (after a bit it can get jumbled otherwise). For your static angles, an unloaded hammock is tricky, always have ~5 pounds as a base point, think a few pillows or sheets or sleeping bag, spread out a bit ... this gives a much better idea of initial setup angles. You obviously will need a helper to measure angles when you get into the hammock, suggest you go over the measurement process and let them do all the angles and record them.

Measuring the angles unloaded and loaded, gives you a feel for how the angles change with load, recording what feels good/bad/ugly helps you zero in on what will work best for you. Once you find the angles that work for you, then just measure the length (loaded) of the ridgeline distance, this length can be adjusted to be structural or ornamental. Also when you make the ridgeline, it is a good idea to stretch the line first, over the 100" length you can get significant "stretch", even non stretch ropes are woven and although the fibers don't stretch, the weave will and 1"-2" will actually make a noticeable difference IMO (maybe not if you can sleep on rocks, lol).

Personally, I have moved to a structural ridge line (the ridgeline basically sets the hang angle, so comes under load) as I find it has a lot of benefits and makes setup easier and more consistent.

I am currently using a bridge hammock, but started with a GE ... for the purpose of zeroing in on hang angles, IMO the discussion is pretty much the same. When I setup the unloaded (~4 pounds distributed load) hammock to the recommended 25 degrees, both foot and head were the same. At 50 kgs, the head/foot angles changed to 28/26 and 100 kgs they moved further to 30/27. So as the hammock loads the actual angles will change and not necessarily at the same rate. Setting the initial angles to 20 degrees, resulted in a 100 kg load angles head/foot of 25/22.

I did quite a few angle tests and found that starting at that 20 degrees was good for me, so I measured up the ridge and installed the structural/fixed ridge line .... setup was straight forward, adjust suspension straps so that the ridgeline was just snug and everything then lines up, just need to make sure head and foot levels are good ... no other adjustments. Used this for 2 years with no issues and a good hang every time ( does require a daily check, stuff stretches).

How sensitive is your setup, well I made a new hammock , same design and it didn't feel right and the bugnet was a bit too tight. I went over the pieces and discovered that I had made the foot suspension lines 2" too long and that threw the rest off a bit .... so pay attention to the details, they can matter ... the degree of importance will be proportional to your own sensitivities.

Brian

**cougarmeat** · 08-03-2024, 11:33

As Cruiser51 indicated, all those measurements are "-ish's", not absolutes. For example, holding your thumb and index finger out like a gun gives you a good estimate of 30 degrees.

The foot end higher than the head end recommendation is also personal with the hanger and hammock design. WarBonnet recommends an 18-inch difference with their BlackBird hammock, in years past, for a gathered-end hammock, 6 to 8 inches was recommended. It's better to ask, "Why?" The why is - that often with a head/food end even, a person would find they had slid down to the the middle/end of the hammock by morning. If that's your experience, you could raise the foot end just enough to stop the nighttime migration. The BlackBird Hammock has a sewn area at the hammock's foot end that lends itself to a diagonal lie. That design allows for the large foot-end, head-end height difference.

Note that as you get shallower than 30 degrees, the pull force on your suspension goes up. For example, with 200 lbs in the hammock, at 30 degrees, that force would be 200 lbs; at 20 degrees, it would be 292 lbs.

One issue with using a structural ridgeline is they are great when you are hooking up to a big ol Ponderosa Pine; an extra 100-200 lbs doesn't matter (if the hammock stitching can take it). My concern, and admittedly I'm a real Cassandra about this, is the shear pull on your interior wall studs.

If possible, a great course would be to go to a park that has a pair of sturdy trees 12 to 15 feet apart and play with different hang angles and head-end, foot-end height differences - as well as overall hammock height above the ground - I like mine about 18 inches above the ground (same as a chair). Then see what you can do to duplicate that at home. If you have construction knowledge or a friend that does, you can explore the ability of whatever you screwed into behind the wall to hold the applied shear forces. There are examples in forum posts of people putting up a frame, exterior to the wall, and hanging on that.

**Shug** · 08-03-2024, 12:54

I'll offer these up for some in sight. Be patient and enjoy the hammock quest.
You only get to be new at it once!
Shug

**Hammock.JJ** · 08-03-2024, 13:00

Originally Posted by Cruiser51

The purpose of the Calculators in general, is just to get you in the ballpark of what will work for you. So you invariably will need to tinker some to get it where it is good for you. Also consider that some folks can sleep on a rock and others are somewhat more fussy ... which is why the motto here is HYOH.

If that ridgeline is structural (takes the ridge load and makes the hammock angle based on its length) it will get tight. If you are just using the ridgeline for hanging stuff (netting, organizers etc) it gets taunt (still able to bend with hands)), not tight (not able to bend with hands).

Now to complicate things a bit, it's my understanding that that "recommended" hang angle is when the hammock is under load. So setting a 30 degree angle will likely get you around 35 degrees with you on board (probably why your ridgeline gets tight IMO). To make this even more fun, since the load is shifted to the head end (top half of body has the largest portion of body mass) the head end and foot end of the hammock don't get the same weight distribution (just in the hammock) ... so while the suspension gets the same load, at either end, the angles aren't usually the same. Having said this about the angles and the impact of loading the hammock on the angles, it is just information to help understand that static angles (unloaded) change the minute you get in the hammock.

The easiest way I've found to check angles, is using a smart phone to just measure the angles, the IPhone has a built in spirit level that works well and I am sure there is an equivalent for android users. Since you are going to be experimenting a bit, I would strongly recommend you makes some notes of the things you try and the stuff you figure out (after a bit it can get jumbled otherwise). For your static angles, an unloaded hammock is tricky, always have ~5 pounds as a base point, think a few pillows or sheets or sleeping bag, spread out a bit ... this gives a much better idea of initial setup angles. You obviously will need a helper to measure angles when you get into the hammock, suggest you go over the measurement process and let them do all the angles and record them.

Measuring the angles unloaded and loaded, gives you a feel for how the angles change with load, recording what feels good/bad/ugly helps you zero in on what will work best for you. Once you find the angles that work for you, then just measure the length (loaded) of the ridgeline distance, this length can be adjusted to be structural or ornamental. Also when you make the ridgeline, it is a good idea to stretch the line first, over the 100" length you can get significant "stretch", even non stretch ropes are woven and although the fibers don't stretch, the weave will and 1"-2" will actually make a noticeable difference IMO (maybe not if you can sleep on rocks, lol).

Personally, I have moved to a structural ridge line (the ridgeline basically sets the hang angle, so comes under load) as I find it has a lot of benefits and makes setup easier and more consistent.

I am currently using a bridge hammock, but started with a GE ... for the purpose of zeroing in on hang angles, IMO the discussion is pretty much the same. When I setup the unloaded (~4 pounds distributed load) hammock to the recommended 25 degrees, both foot and head were the same. At 50 kgs, the head/foot angles changed to 28/26 and 100 kgs they moved further to 30/27. So as the hammock loads the actual angles will change and not necessarily at the same rate. Setting the initial angles to 20 degrees, resulted in a 100 kg load angles head/foot of 25/22.

I did quite a few angle tests and found that starting at that 20 degrees was good for me, so I measured up the ridge and installed the structural/fixed ridge line .... setup was straight forward, adjust suspension straps so that the ridgeline was just snug and everything then lines up, just need to make sure head and foot levels are good ... no other adjustments. Used this for 2 years with no issues and a good hang every time ( does require a daily check, stuff stretches).

How sensitive is your setup, well I made a new hammock , same design and it didn't feel right and the bugnet was a bit too tight. I went over the pieces and discovered that I had made the foot suspension lines 2" too long and that threw the rest off a bit .... so pay attention to the details, they can matter ... the degree of importance will be proportional to your own sensitivities.

Brian

Wow...never thought about loaded/unloaded. More tinkering ahead :-) thanks!

**Hammock.JJ** · 08-03-2024, 13:04

Originally Posted by cougarmeat

As Cruiser51 indicated, all those measurements are "-ish's", not absolutes. For example, holding your thumb and index finger out like a gun gives you a good estimate of 30 degrees.

The foot end higher than the head end recommendation is also personal with the hanger and hammock design. WarBonnet recommends an 18-inch difference with their BlackBird hammock, in years past, for a gathered-end hammock, 6 to 8 inches was recommended. It's better to ask, "Why?" The why is - that often with a head/food end even, a person would find they had slid down to the the middle/end of the hammock by morning. If that's your experience, you could raise the foot end just enough to stop the nighttime migration. The BlackBird Hammock has a sewn area at the hammock's foot end that lends itself to a diagonal lie. That design allows for the large foot-end, head-end height difference.

Note that as you get shallower than 30 degrees, the pull force on your suspension goes up. For example, with 200 lbs in the hammock, at 30 degrees, that force would be 200 lbs; at 20 degrees, it would be 292 lbs.

One issue with using a structural ridgeline is they are great when you are hooking up to a big ol Ponderosa Pine; an extra 100-200 lbs doesn't matter (if the hammock stitching can take it). My concern, and admittedly I'm a real Cassandra about this, is the shear pull on your interior wall studs.

If possible, a great course would be to go to a park that has a pair of sturdy trees 12 to 15 feet apart and play with different hang angles and head-end, foot-end height differences - as well as overall hammock height above the ground - I like mine about 18 inches above the ground (same as a chair). Then see what you can do to duplicate that at home. If you have construction knowledge or a friend that does, you can explore the ability of whatever you screwed into behind the wall to hold the applied shear forces. There are examples in forum posts of people putting up a frame, exterior to the wall, and hanging on that.

I do need to get out between some trees for safety' sake and for experimentation sake. I think I've done all I can safely do with my two 5.7 ft. High anchor points.

**Hammock.JJ** · 08-03-2024, 13:10

Shug...I've watched a lot of your videos multiple times. "Does your hammock fit you" comes immediately to mind! I guess I really need a better experimentation setup like you have outside or I'll just get out in the woods. I remember one of your hammocks had a ridgeline in the low 70ish percent. I haven't been table to try that. I feel like I'm talking to a celebrity :-)

**Shug** · 08-03-2024, 13:26

Originally Posted by Hammock.JJ

Shug...I've watched a lot of your videos multiple times. "Does your hammock fit you" comes immediately to mind! I guess I really need a better experimentation setup like you have outside or I'll just get out in the woods. I remember one of your hammocks had a ridgeline in the low 70ish percent. I haven't been table to try that. I feel like I'm talking to a celebrity :-)

Don't be afraid to more that ridgeline a lot either way to see what it feels like or if you even need or want one. Those percentages are just a starting place but I adjust my ridge lines often depending on my hang spacing.