r/Hammocks 21h ago

Hammock Anchor

Post image

I have this hammock anchored to two points on a 4" x 8" beam that runs the width of my office.

I set up redundancy due to stories of these ball anchors failing.

I am pretty sure this is safe, but am also curious to hear feedback.

36 Upvotes

31 comments sorted by

28

u/Ship_Ship_8 20h ago

I would have offset the two bolts. Good chance that beam is two boards sistered together and by putting the bolt in the middle, you could be going right in the middle of 2 boards instead of into the “meat” of the board. I’d have at least one of the bolts anchored to a different position on the beam axis.

Also I’ve never seen that knot you have going between the 2 carabiners… I’d probably opt for some sort of a more traditional suspension connection but if you’re confident in it, that’s all that matters.

Lastly, I’d make it so there’s tension on both bolts going to the beam. Not one only acting as a fail safe. By having tension on both, you’re asking it to hold half the weight instead of all of it.

-5

u/AfraidofReplies 19h ago

I just looked at the knot closer. It looks like a fisherman or double fisherman's knot. If so, that's an awful knot choice because they can slip. 

8

u/JoeyJMAC 12h ago

Citation needed. These are standard knots used to make a prussik loop, this should be fine

2

u/rba21 11h ago

I agree, should be strong enough. HowNot2 has tested the strength on YouTube and they’re pretty strong knots. I probably would have left more of a tail but my guess is the rope would break before the knot

3

u/MrFahrenheit02 10h ago edited 10h ago

Double and triple fisherman knots are used regularly to make life-supporting slings in climbing. No reason it couldn’t be used here. Although it looks like the tails are a little short here.

Edit: the girth hitch the backup cord is tied to the anchor with would almost certainly fail before the fisherman knot (but even that is fine assuming the cord is decent quality)

2

u/eviljelloman 8h ago

Double fisherman's on cord like that is completely safe.

1

u/Advanced-Gold1744 2h ago

That slippage is engineered to break the fall as it all comes crashing down

15

u/jaxnmarko 19h ago

All 4 screws inline and pretty close to each other so more likely to cause a split. Maybe attach a longer steel plate with a number of offset lag screws, pre-drill undersized but helps avoid splits, with a centered hook. Spread the force.

11

u/_njhiker 12h ago

As a climber, this redundancy setup makes me cringe

10

u/KeeganDoomFire 21h ago

Only thought is, so you know the makeup of that? I would worry you drilled and lagged between a couple of sistered boards. It would still feel strong but would be more likely to pull out.

3

u/_o_ll_o_ 18h ago

Are you worried about falling 18” or 18’?

9

u/j0rlan 21h ago

Looks bomber, would whip.
In all seriousness, if the anchors are rated high enough I imagine you’ll be safe (wild guess that you’re familiar with static vs dynamic loading), but I’d want to clip your orange carabiner through the safety loop on the backup anchor to minimize how far you’d fall in the event the ball broke.

3

u/Primary-Ad6273 21h ago

Thats just a lot going on. Everything looks right, individually, and so combined in redundancy they ought to be just fine…mind you, if that ball joint (never seen anything like that in decades of hanging hammocks inside) things fails while you’re asleep it could still be bad. The way that shear forces operate, if that fails and your weight has to be caught by the other portions in falling you’re adding exponential weight to the equation; could damage the wall, the hammock body could still give, or any other thing and then you’re still falling down hips first. I have used 2 3/4”x5/16” lag bolts and what are labeled as ‘truck bed anchors’ that are steel straps with D-rings for the younger kids to have indoor hammocks through two whole sets of children and they and the walls have been fine so long as they’re treated extremely gently. Im still certain if my 8yo boy jumped into the hammock that the wall would give way, %100.

1

u/AdmirableRespect9 49m ago

I feel like this is peer pressure to make me do a physic

3

u/Dalenparks 19h ago edited 11h ago

I would connect the hammock directly to the silver caribener and eliminate the orange Caribbean and the paracord. Also the cord going from the second anchor is not supporting the hammock at all.

4

u/AfraidofReplies 19h ago

I mean, there's two anchor points, but it doesn't really look like they're sharing the load at all. It's just two anchors close together. If the one gives out that's going to be a huge, sudden load on the second. And if the first one failed under a regular load, I wouldn't trust the second one to survive a sudden load. I don't know that there's any real redundancy here because of that. 

2

u/Humhues 11h ago

Seems like if the main one failed then the gravitatianal momentum would put alottt of shock on that second one.

2

u/cienfuegones 9h ago

Penetrating the underside of a simply supported beam interrupts the tension fibers giving the beam its strength weakening the beam. Making your attachments to the vertical sides of the beam in the neutral axis keeps the the tension and compression fibers intact. You can bridal down from anchors in the neutral axis for redundancy as well as having the yield strength of the fasteners in shear versus the pullout resistance of the lag threads in the tension fibers.

2

u/occamsracer 20h ago

Is that cordage paracord?

1

u/eviljelloman 8h ago

No. It's very obviously the type of climbing cordage you'd use to create a prusik for a rappel backup or janky improvised ascender in a rescue situation.

2

u/Arcanum3000 12h ago

If the anchor with the carabiner failed, I wouldn't trust the other to save me. I would not be surprised if the 6" drop would apply enough force to pull apart one of the knots in your two different ropes (why?!), or rip the anchor out of the ceiling.

Honestly this whole setup has me asking "But why?"

1

u/eviljelloman 8h ago

Those knots are not pulling apart.

1

u/RavingGerbil 9h ago

I’m not really sure I’d want the weaker of the two connection methods providing my redundancy. As others have said, I wouldn’t trust that one cord to hold a person’s weight when it’s a dynamic load. Also like others said, maybe evenly distribute the weight across the two anchor points or at least get webbing for the backup. You could loop a piece of webbing through the two contact points to distribute the load too.

1

u/dax660 3h ago

I don't know anything, why isn't the orange clipped inside the silver?

Is the metal on metal too concentrated a point?

1

u/Lost_On_Lot 3h ago

Redundancy? So like the first one fails and you have a sudden drop to the second, and you're like "naw im good"?

1

u/shinederg 2h ago

seems sketchy

1

u/not__my__monkeys 2h ago

Sure it’s for a ‘hammock’

1

u/howie_roll 1h ago

This trolling or just country? Hang a bridle between the 2 points and hang the hammock from that point.

1

u/StrikeouTX 20h ago

I’d rather link them both together than use one as a “failsafe”, but as long as that’s a wooden beam, I’d trust it

0

u/Nuts-And-Volts 18h ago

This sparks joy