Forums: Climbing Information: Gear Heads: Re: [dynosore] Sewing your own slings: Edit Log




splish


Jul 30, 2012, 6:44 PM

Views: 9619

Registered: Aug 21, 2005
Posts: 143

Re: [dynosore] Sewing your own slings
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (3 ratings)  

dynosore wrote:
splish wrote:
Rudmin wrote:
spikeddem wrote:
Gthomann, you keep saying the forces in a TR setup aren't much. I'm curious about the numbers you have for that. What forces have you observed?

I'd also be a bit surprised if it took a thousand pounds of force to lift the tail of a truck off the ground. Maybe if it was a pretty big truck with entirely too much junk in its trunk.

That truck probably weighs around 5000 lbs. If the centre of gravity was halfway between the front wheel and the hitch, he would be pulling up 2500 lbs. Since it's probably forward of that, 1000 lbs sounds like a very reasonable conservative estimate.

I have a full size SUV, with straight axles, and it doesn't weight 5000 lbs. The weight of any vehicle is on the door. The truck has no weight in the back. In high school, me and 3 other guys used to lift the back of Jeff's truck off the ground and turn it sideways in the parking spot. The back of a truck is ridiculously light!!!
Lift the engine, then I will be impressed. But I don't understand why this guy doesn't test it the same way UIAA does, put a wieght on it and drop it! find a porch or balcony or something. And a sand bag or some dumb bell weights!

Again, a full size pickup has a weight distribution around 55/45 front/rear, depending on box length, 2wd or 4wd, etc. Three of you picked up 2000 lbs or more?

What "full size" SUV do you have that weighs less than 5k pounds? A Tahoe, Suburban, or Expedition weighs between 5200-6500 lbs depending on the model. What do you drive?

I have a 2004 Nissan Pathfinder Chinook. Added equipment includes 8' of 1/4" steel skid plates, ARB Winch Mount 1/4" steel bumper, snorkel assembly, dual battery, various off road lights and a winch. Lat time I went through a scale, it weighed in a 2404 KG. And that is with 2 full grown adults sitting inside. Just over 5000 Lbs, so the stock Pathy weighs much less I assure you.
I just looked up a few dodge trucks on Google, and they all do weight over 5000 lbs, but in the back end the only weight is the box, the back half of the frame, the drive shaft and the rear axle assembly. I am not sure of the exact weight distribution, But I wouldn't think it to be the the 55/45 that you stated, I think it would be much less.
As for the truck we used to life in high school, it was a 1983 GMC S15, which is smaller than the current Canyon. A very small truck, and the back end was incredibly light. We would kind of bounce it until the tires left the ground, and move it a few inches at a time until we turned it sideways across 2 parking spots with a car immediately in front and behind so he could not leave until those cars were gone.
My point is, lifting the rear end of a truck off the ground with a sling proves little when it comes to the forces involved in climbing.
Also, looking at the photo of the lifted truck. They used a small hand operated hydraulic crane rated to 4000 lbs and the boom is not showing any signs of deflection. Having used these devices many times, I can tell you, when you lift close to the rated weight of the device, there is at least an inch and a half or more of deflection in the boom.
Also, if you click on the photo and blow it up to full size, you can clearly see that only one rear tire is approx. 3" off the ground while the driver side tire is still firmly planted on the concrete. The chain that they used to wrap the bumper and lift from looks to be a much smaller size as well, not rated for heavy lifting. Much smaller than tow chains. This is really not a very impressive lift, nor do I think that this experiment would prove his stitching to be climbing worthy.


(This post was edited by splish on Jul 30, 2012, 6:53 PM)



Edit Log:
Post edited by splish () on Jul 30, 2012, 6:50 PM
Post edited by splish () on Jul 30, 2012, 6:53 PM


Search for (options)

Log In:

Username:
Password: Remember me:

Go Register
Go Lost Password?