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Definitely interesting! I wonder if they will be able to hit their goal by June 11.
 

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They'll need to sell 60 more to make it. I just put in for one, so only 59 to go...

Looks like a neat product if its well built. Certainly easier and lighter to pack than an earth anchor or burying a spare tire. Not sure it will replace any gear in my kit, but a welcome addition.
 

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love the idea, but I have my serious doubts about the claims they are making. The number of variables you would have to account for to verify them, are about directly proportionate to the number of possible recovery situations, soil type, soil humidity, vehicle type, etc.

They would need to do some very serious lab and field testing to get anywhere near being able to make any such claims, and yet the failure mode is pretty obvious and might be the only thing that is easily reproducible. Probably works like a Medieval trebuchet when it pulls out of the ground under load.
 

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I'm in for one. Looks like it would be very versatile.

Just the materials would cost $50-60, plus cutting and sewing. Time is money. And not having to reverse engineer, source, cut, sew, etc., is definitely worth $100 to me.
 

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Quality idea. It's another one of those DUH products. Why did it take so long to invent it?

I don't think I'll personally use one just because I've never needed one in the past. Now that I say that, I'm sure I'll be stuck and needing one soon lol. It's a brilliant product, they'll make their kickstarter numbers soon.
 

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I was trying to put my finger on what bothered me about that system. I think I got it.

I use to be big in to rock climbing, and have seen all kinds of crazy anchoring systems. It is kind of like the old systems where they would tie a knot in the rope, and wedge it in to a crack (still used in places were metal is not allowed on the rock). Works fine for a 200 pound human, but I would not put thousands of pounds on it.

Where that might really go wrong, is the soil inside the bag under load compressing. It will not behave like say a spare tire that does not compress under load.

Perhaps with more than one, I would feel better about it.
 

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Good stuff guys! Nice to help out some of our own (Yota guys). Thing could even be helpful as a tarp or small thing to lay on if you need to crawl under the truck for something.

On to what cenc said above, I wonder if you could put a reasonably large rock in it, and then wedge it between other rocks....might be too much force in the middle of it though.
 

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I think it would work, and I like it, I just would like to see some lab test or engineering math behind it. For example, what happens when the water in different sorts of soil is squeezed out under load?

I was just thinking about what happens to different soils when you build a house on them, and for example in an earthquake the soil liquefies because of higher water content between the grains. The soil becomes less able to support loads.

Can you consistently say, under all conditions, that it will support a minimum 5,000 or 10,000 or whatever pounds of force?
 

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Would burying this thing in the sand a couple of feet really hold the weight of an FJ being pulled up hill?? I would be worried about it pulling out of the sand :)
 

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This thing is really just an improvement on a very old "TRICK". Before this gizmo you would dig your hole or get your wife to do it and bury your spare tire with the winch connected to it. Would it pull uphill in the sand? Depends on the winch. If she dug the whole deep enough the weight of the sand and if needed you can use your Hylift jack as a sand spike to add additional deadman at the spare tire before you bury it.


Sent from my iPad using Tapatalk
 

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I was trying to put my finger on what bothered me about that system. I think I got it.

I use to be big in to rock climbing, and have seen all kinds of crazy anchoring systems. It is kind of like the old systems where they would tie a knot in the rope, and wedge it in to a crack (still used in places were metal is not allowed on the rock). Works fine for a 200 pound human, but I would not put thousands of pounds on it.

Where that might really go wrong, is the soil inside the bag under load compressing. It will not behave like say a spare tire that does not compress under load.

Perhaps with more than one, I would feel better about it.
Well hello, everyone! I'm Daniel with Deadman Off-Road.

Your concerns are valid, @cenc. In fact, we had similar thoughts and concerns when we began down this path two years ago. We've learned a lot in our field & lab testing since then, so I'd like to address your concerns here one at a time. If you have any other concerns or questions, please let us know!


  1. How is this different from a sand parachute used in rock climbing or snow? When we began down this path, these smaller anchor methods were certainly in the back of our minds. Bryant (a long-time rock climber) and I (also a climber trained in high-angle rescue and other rescue operations) were familiar with parachute style ground anchors. We knew it was possible to anchor smaller weights in the ground, but what about the weight of a vehicle? Being an engineer, Bryant knew it could work in principle, but needed to find answers to questions like "how large would the anchor need to be," "how deep would the hole need to be," "what effect would soil density have on these variables," "would it work in hi- and low-angle pulls," etc, etc, etc. Over time and lots of field testing, we found answers to these questions. We also learned that simply filling a bag with dirt and pulling on it wasn't enough to make the Deadman work - at least, not at any depth we'd be willing to dig to! It wasn't until we learned to offset the front & back lines - essentially turning the sandbag into a hook - that it began to work reliably and at shallower depths.
  2. Efficacy in varying soil. With a functional design complete, we began testing different soil types and various depths. Because the Deadman was operating as a hook within the ground, we learned that the density of the soil around the Deadman played as much a role in its holding power as the depth to which it was buried. In shifting soil (e.g. soft sand), the Deadman will eventually cut through the earth under load. (See Testing below.) However, in hardpack (e.g. the harder soil atop a soft hill climb or off the side of a muddy trail), the Deadman holds fast at a much shallower depth because the surrounding soil does not move as easily. Regardless, we have learned a lot about the relationship between soil density, hole depth, and anchor load capacity.
  3. Certified lab testing. We're working with BC Wire Rope in Anaheim right now to test and certify our design for actual assembly breaking strength. We will share this data when we've completed the testing, but initial tests put our straps within range of our design goals. We recently tweaked the assembly design to achieve greater MBS and will be testing this tomorrow. We want more than "good enough," so we're continuing to alter the design to get greater strength.
  4. Testing approach. We're data nerds. Our backgrounds in engineering and enterprise business led us to gather empirical data about the Deadman. We know the raw numbers: 2" Class VII poly webbing with a MBS of 19,600 in straight pull and 39,200 in a basket, 2x lines makes it twice as strong, our WLL based on a safety factor of 3:1, etc, etc, etc... But what does it take to recover a vehicle? How much weight can the Deadman hold in different soils and at different depths? We used a load cell to gather this data in the softest soil we could find: Baja desert-type sand. Being on the border of the US & Mexico, we have access to some pretty soft stuff.
  5. Force required to recover a 6,000lb Tacoma Through testing, we observed that it takes less force than we realized to recover such a heavy object. Of course, each recovery scenario is unique and the variables of soil, terrain, angle of the terrain, angle of the recovery, etc will affect these numbers, but the tests we conducted gave us a very good baseline with which to gauge future recoveries. We observed that our 6,000lb Tacoma on 35" tires, buried to the frame in soft sand, only required 1,800lb to recover when the truck was in Drive. When the truck was simply in Neutral, it still only required 4,000lb to pull it up and out of the hole.
  6. Deadman vs Spare Tire in soft sand. Our first test was a side-by-side with the old DIY method of burying a spare tire. Aside from the obvious difficulties of a spare (possibly excavating it from a mount underneath the vehicle, oversized off-road spares, weight, digging it back out after the recovery, etc), we wanted to see if the Deadman offered any other advantages - particularly in terms of its holding power. We took a stock 29" spare from our Tacoma and buried it in a 30" hole. We attached a tree strap to the bottom of the tire (through the center in a choker config), trenched the line and attached the load cell to the anchor and to the winch. Next, we buried the Deadman at the same 30" depth and attached a load cell there. Results: The spare tire gave us 2,500lb peak force before the sand around it quickly gave way and it rose out of the hole. Once it began to move, the tire only provided about 500lb of force. The Deadman measured 4,900lb force, but more surprisingly, it continued to provide 3,900lb of force after the ground around it gave way and it began cutting through the sand. Same depth hole, almost 2x as strong and provided sustained capacity.
  7. Deadman at varied depths in soft sand. Again testing in the soft Baja-style sand, we tried burying the Deadman +/- 6" vs our 30" tire test. At 24" the Deadman held 2,600lb (slightly more than the spare when it was 6" deeper) and 2,100lb sustained. When we buried it to 36", the Deadman held 7,100lb peak, 6,100lb sustained. To put that into perspective, we had to put the Tacoma on its frame rails in the sand, hold the brakes, and use a double-line pull - all four tires were being drug through the sand during this test. Below is a video of the 36" test before I jumped back into the vehicle to hold the brakes. (Yes, it was dangerous for me to be that close to the anchor...) In the video, you can see the load cell readout at about 5,800lb. Once I was on the brakes I was able to register 7,100lb, which is why you can't see it in the video.
  8. Deadman efficacy in a high-angle pull in dune sand. We also set up a hi-centered dune crest scenario to test how the Deadman would work at an extreme angle. Obviously, the high angle reduces the Deadman's ability to act as a hook, and the soft blow sand made it very difficult to dig a hole of any considerable depth. Regardless, we were able to bury the Deadman in a few inches of sand and register a peak of 1,100lb as it moved through the sand, recovering the Tacoma in the process. As you can see in the next video, the truck was resting on its frame rails with both the F & R tires spinning freely.
  9. Deadman at shallower depths in hardpack. Some of our earlier tests focused on hardpack at the top of a sandy hill climb - we have a lot of those out here in the San Diego desert. Because the soil does not part as easily when it's this dense, anchoring in hardpack allows us to dig a shallower hole. In this next video (sorry, no load cell), we buried the Deadman to about 24" and used it to climb up the sandy slope. As you can see in the video, it settles in and then holds fast. The images below show another similar test at 22" from last weekend on a longer, steeper, softer hill climb.

 

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Great response. Hell, I am blown away that you showed-up to explain it.

I think the number one detail from all that, that perhaps might be worth emphasizing in your promotion, is the digging in / scoop / sand anchor function as it is loaded or slips.

That in my mind, makes all the difference in understanding the design. I think the thing that was not clear to me, was what does it look like when it pops out of the ground (i.e. when the soil fails vs the device failing).

I look forward to ordering one, and wish you guys the best of luck.

A winch with nothing to connect to is rather worthless.
 

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Great response. Hell, I am blown away that you showed-up to explain it.

I think the number one detail from all that, that perhaps might be worth emphasizing in your promotion, is the digging in / scoop / sand anchor function as it is loaded or slips.

That in my mind, makes all the difference in understanding the design. I think the thing that was not clear to me, was what does it look like when it pops out of the ground (i.e. when the soil fails vs the device failing).

I look forward to ordering one, and wish you guys the best of luck.

A winch with to nothing connect to is rather worthless.
Thank you for the feedback! That makes a lot of sense... I have seen similar concerns/questions from others, so now I understand that I should go back and edit the Kickstarter page to better make that point. I think we can add in some images of what happens when you reach the load limit of your hole too.

Thanks for the support folks! Please hit us up with any more questions as they come to mind.

See you on the trails!
 

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yea, I was thinking a diagram or something showing it digging in as it slips through the soil would be helpful.
 

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Well hello, everyone! I'm Daniel with Deadman Off-Road.

Your concerns are valid, @cenc. In fact, we had similar thoughts and concerns when we began down this path two years ago. We've learned a lot in our field & lab testing since then, so I'd like to address your concerns here one at a time. If you have any other concerns or questions, please let us know!


  1. How is this different from a sand parachute used in rock climbing or snow? When we began down this path, these smaller anchor methods were certainly in the back of our minds. Bryant (a long-time rock climber) and I (also a climber trained in high-angle rescue and other rescue operations) were familiar with parachute style ground anchors. We knew it was possible to anchor smaller weights in the ground, but what about the weight of a vehicle? Being an engineer, Bryant knew it could work in principle, but needed to find answers to questions like "how large would the anchor need to be," "how deep would the hole need to be," "what effect would soil density have on these variables," "would it work in hi- and low-angle pulls," etc, etc, etc. Over time and lots of field testing, we found answers to these questions. We also learned that simply filling a bag with dirt and pulling on it wasn't enough to make the Deadman work - at least, not at any depth we'd be willing to dig to! It wasn't until we learned to offset the front & back lines - essentially turning the sandbag into a hook - that it began to work reliably and at shallower depths.
  2. Efficacy in varying soil. With a functional design complete, we began testing different soil types and various depths. Because the Deadman was operating as a hook within the ground, we learned that the density of the soil around the Deadman played as much a role in its holding power as the depth to which it was buried. In shifting soil (e.g. soft sand), the Deadman will eventually cut through the earth under load. (See Testing below.) However, in hardpack (e.g. the harder soil atop a soft hill climb or off the side of a muddy trail), the Deadman holds fast at a much shallower depth because the surrounding soil does not move as easily. Regardless, we have learned a lot about the relationship between soil density, hole depth, and anchor load capacity.
  3. Certified lab testing. We're working with BC Wire Rope in Anaheim right now to test and certify our design for actual assembly breaking strength. We will share this data when we've completed the testing, but initial tests put our straps within range of our design goals. We recently tweaked the assembly design to achieve greater MBS and will be testing this tomorrow. We want more than "good enough," so we're continuing to alter the design to get greater strength.
  4. Testing approach. We're data nerds. Our backgrounds in engineering and enterprise business led us to gather empirical data about the Deadman. We know the raw numbers: 2" Class VII poly webbing with a MBS of 19,600 in straight pull and 39,200 in a basket, 2x lines makes it twice as strong, our WLL based on a safety factor of 3:1, etc, etc, etc... But what does it take to recover a vehicle? How much weight can the Deadman hold in different soils and at different depths? We used a load cell to gather this data in the softest soil we could find: Baja desert-type sand. Being on the border of the US & Mexico, we have access to some pretty soft stuff.
  5. Force required to recover a 6,000lb Tacoma Through testing, we observed that it takes less force than we realized to recover such a heavy object. Of course, each recovery scenario is unique and the variables of soil, terrain, angle of the terrain, angle of the recovery, etc will affect these numbers, but the tests we conducted gave us a very good baseline with which to gauge future recoveries. We observed that our 6,000lb Tacoma on 35" tires, buried to the frame in soft sand, only required 1,800lb to recover when the truck was in Drive. When the truck was simply in Neutral, it still only required 4,000lb to pull it up and out of the hole.
  6. Deadman vs Spare Tire in soft sand. Our first test was a side-by-side with the old DIY method of burying a spare tire. Aside from the obvious difficulties of a spare (possibly excavating it from a mount underneath the vehicle, oversized off-road spares, weight, digging it back out after the recovery, etc), we wanted to see if the Deadman offered any other advantages - particularly in terms of its holding power. We took a stock 29" spare from our Tacoma and buried it in a 30" hole. We attached a tree strap to the bottom of the tire (through the center in a choker config), trenched the line and attached the load cell to the anchor and to the winch. Next, we buried the Deadman at the same 30" depth and attached a load cell there. Results: The spare tire gave us 2,500lb peak force before the sand around it quickly gave way and it rose out of the hole. Once it began to move, the tire only provided about 500lb of force. The Deadman measured 4,900lb force, but more surprisingly, it continued to provide 3,900lb of force after the ground around it gave way and it began cutting through the sand. Same depth hole, almost 2x as strong and provided sustained capacity.
  7. Deadman at varied depths in soft sand. Again testing in the soft Baja-style sand, we tried burying the Deadman +/- 6" vs our 30" tire test. At 24" the Deadman held 2,600lb (slightly more than the spare when it was 6" deeper) and 2,100lb sustained. When we buried it to 36", the Deadman held 7,100lb peak, 6,100lb sustained. To put that into perspective, we had to put the Tacoma on its frame rails in the sand, hold the brakes, and use a double-line pull - all four tires were being drug through the sand during this test. Below is a video of the 36" test before I jumped back into the vehicle to hold the brakes. (Yes, it was dangerous for me to be that close to the anchor...) In the video, you can see the load cell readout at about 5,800lb. Once I was on the brakes I was able to register 7,100lb, which is why you can't see it in the video.
    Sand Load Cell - YouTube
  8. Deadman efficacy in a high-angle pull in dune sand. We also set up a hi-centered dune crest scenario to test how the Deadman would work at an extreme angle. Obviously, the high angle reduces the Deadman's ability to act as a hook, and the soft blow sand made it very difficult to dig a hole of any considerable depth. Regardless, we were able to bury the Deadman in a few inches of sand and register a peak of 1,100lb as it moved through the sand, recovering the Tacoma in the process. As you can see in the next video, the truck was resting on its frame rails with both the F & R tires spinning freely.
    Dune Recovery - YouTube
  9. Deadman at shallower depths in hardpack. Some of our earlier tests focused on hardpack at the top of a sandy hill climb - we have a lot of those out here in the San Diego desert. Because the soil does not part as easily when it's this dense, anchoring in hardpack allows us to dig a shallower hole. In this next video (sorry, no load cell), we buried the Deadman to about 24" and used it to climb up the sandy slope. As you can see in the video, it settles in and then holds fast. The images below show another similar test at 22" from last weekend on a longer, steeper, softer hill climb.
    Deadman Saves - Split Screen Recovery - YouTube

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