At what body weight is 7/64 Amsteel not enough?

**OrangePeel** · 11-15-2012, 00:41

Hi all,

My ENO DoubleNest is coming in tomorrow and I was thinking about heading to West Marine to pickup some Amsteel and make some whoopie slings. Then I remembered reading about all of the angles and weights suspension systems can see and it made me wonder... is 7/64 enough? At what body weight, if any, should I use 1/8 instead?

Thanks,

Brandon

**pgibson** · 11-15-2012, 00:46

We have done 24 hour continuous dynamic load testing to 600 pounds on 7/64 in house. Another vendor has had lab testing done to breaking point, failure was at full rating. Unless your going to host a small party in your hammock, you know with a band, 3 kegs, those what's up guys from 2004.........Sorry its getting late and dis not sleep well last night.......You will be fine with 7/64.

**OrangePeel** · 11-15-2012, 01:10

LOL... thank you for the imaginative reasoning.

I wasn't sure if they would be put under more than just my body weight or not.

Brandon

**SGT Rock** · 11-15-2012, 01:14

If I remember correctly 7/64th Amsteel is rated to about 1600 lbs. So if you went by the 1:5 rule of thumb, that makes it good to about 320 pounds.

**SmokeBait** · 11-15-2012, 11:47

Originally Posted by SGT Rock

If I remember correctly 7/64th Amsteel is rated to about 1600 lbs. So if you went by the 1:5 rule of thumb, that makes it good to about 320 pounds.

I'll second what the Sarge says. The 7/64" Amsteel will take higher loads but I like a safety factor since we are dealing with static and dynamic loads in a hammock suspension.

**OrangePeel** · 11-15-2012, 01:22

Sweet... I'm 70 lbs below that.

What is the 1:5 rule of thumb?

Brandon

**Gresh** · 11-15-2012, 01:26

Originally Posted by OrangePeel

Sweet... I'm 70 lbs below that.

What is the 1:5 rule of thumb?

Brandon

Whatever you're using, you want it to be able to support five times your weight. I use 1/8 Amsteel.

**ahhhgladius** · 11-16-2012, 15:52

Originally Posted by Gresh

Whatever you're using, you want it to be able to support five times your weight. I use 1/8 Amsteel.

he got confused and thought 1/20 rule and bought 1/2 inch first. we now rearrange trees at the site.

**OrangePeel** · 11-16-2012, 16:12

**DemostiX** · 11-15-2012, 01:36

Do a bit of search on engineering safety margins for cordage. IMO, Sgt is being liberal. A margin of 5 to 1 is for non-human support, so 5 to 1 will be the ratio of strength to maximum working load for such as tow ropes and straps. 10-15 to 1 is the safety margin for human loads.

On the other hand, and it is a strong hand.

The load is almost shared by two cords, each bearing about half the weight.
Engineering conservatism appropriately assumes that the cord will be terminated in knots which will compromise the strength by 40-60%. On average ,then, there's a need for cord that is twice as strong as its maximum expected static load. However, and in contrast, you will find in HF everywhere, descriptions of proper splicing methods for (hollow braid) Amsteel, which result in no more than a 10% strength loss from terminations. So, that source of risk to safety is minimized. Further, IIANM, the rating on Amsteel from Sampson Rope is already of a properly spliced line.