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acorneau
Oct 21, 2010, 6:06 PM
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Khoi wrote: ozoneclimber wrote: OK....... The obvious question:
Why not just use tubular webbing and a water-knot? You, and everyone else, know that it is tried and true. Why complicate things when you don't have to? -B gthomann I'd really like to know your answer to this.
Because he wants to make his own PTFTW's.
Why did some folks make a cam for the Lab cam contest? Curiosity, perhaps?
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seatbeltpants
Oct 21, 2010, 7:09 PM
Post #27 of 101
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acorneau wrote: Khoi wrote: ozoneclimber wrote: OK....... The obvious question:
Why not just use tubular webbing and a water-knot? You, and everyone else, know that it is tried and true. Why complicate things when you don't have to? -B gthomann I'd really like to know your answer to this. Because he wants to make his own PTFTW's. Why did some folks make a cam for the Lab cam contest? Curiosity, perhaps?
curiosity is cool - but how many of those who made cams for the contest actually climbed on them?
steve
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Paul_W
Oct 21, 2010, 9:53 PM
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back in the day we used to sew our own slings. i made a complete set from 9/16 webbing and used poylester thread and an old sewing machine. i did take care to make sure the tension was right and inspected the bar tacks carefully. i took dozens of screamers on these and never had a problem. that said, the new gear is so light and nice why not pay a few bucks and buy some new slings, or if you can't afford that just use tied slings until you can afford some commercially sewn ones.
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buck0land
Oct 23, 2010, 2:39 PM
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What about contacting a master rigger for information on sew soft goods?
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russwalling
Oct 23, 2010, 4:03 PM
Post #30 of 101
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In reply to: 2.) Your stitches are really sloppy. A bartack is just a really tight zig-zag stitch but it it should be tight and ordered. You might try going slower when stitching or maybe your machine has a buttonhole setting. You also might try adding some appropriate adhesive between the webbing prior to sewing so that the piece is easier to handle.
A bartack is NOT just a really tight zigzag. There is more to it than that. (note to self: do not feed the trolls)
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bill413
Oct 24, 2010, 12:48 AM
Post #31 of 101
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russwalling wrote: In reply to: 2.) Your stitches are really sloppy. A bartack is just a really tight zig-zag stitch but it it should be tight and ordered. You might try going slower when stitching or maybe your machine has a buttonhole setting. You also might try adding some appropriate adhesive between the webbing prior to sewing so that the piece is easier to handle. A bartack is NOT just a really tight zigzag. There is more to it than that. (note to self: do not feed the trolls)
But this is a point worth getting out...thanks Russ.
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oldrnotboldr
Oct 24, 2010, 3:44 AM
Post #32 of 101
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I saw a guy try to use homemade slings designed just like yours, it DID NOT HOLD EVEN ONE TOP ROPE FALL. Fortunately, the guys' set up was redundant and kept serious injury from happening. He rightly never used nor tried to self manufacture anymore.
Use commercial gear or the tried and true knotting methods. Otherwise "yer gonna die" and that is no exaggeration.
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acorneau
Oct 24, 2010, 1:01 PM
Post #33 of 101
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oldrnotboldr wrote: I saw a guy try to use homemade slings designed just like yours...
I'm guessing that was intended for the OP and not me, right?
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oldrnotboldr
Oct 24, 2010, 5:12 PM
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No, not you but the OP. That event was some years ago and the guy had the idea he could save some money. While the sling would hold static body weight, a fall ripped it faster than a screamer. I'm sure its possible to make your own but why. Considering the correct supplies, equipment, time, etc. it is not that cost effective. Plus, finding a way to properly test the final product. There are better, safer, cheaper, alternatives. I'm very nervous about any home made equipment.
As a side note to the OP--I hear that HomeDepot has some carabiners that would hold body weight also.
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gmggg
Oct 25, 2010, 2:39 PM
Post #36 of 101
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russwalling wrote: In reply to: 2.) Your stitches are really sloppy. A bartack is just a really tight zig-zag stitch but it it should be tight and ordered. You might try going slower when stitching or maybe your machine has a buttonhole setting. You also might try adding some appropriate adhesive between the webbing prior to sewing so that the piece is easier to handle. A bartack is NOT just a really tight zigzag. There is more to it than that. (note to self: do not feed the trolls)
Not trolling, I understand the stitch to be identical. I'd be interested to learn the difference if there's a resource you could point too or an explanation you could offer.
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kennoyce
Oct 25, 2010, 2:56 PM
Post #37 of 101
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seatbeltpants wrote: acorneau wrote: Khoi wrote: ozoneclimber wrote: OK....... The obvious question:
Why not just use tubular webbing and a water-knot? You, and everyone else, know that it is tried and true. Why complicate things when you don't have to? -B gthomann I'd really like to know your answer to this. Because he wants to make his own PTFTW's. Why did some folks make a cam for the Lab cam contest? Curiosity, perhaps? curiosity is cool - but how many of those who made cams for the contest actually climbed on them? steve
I've climbed on homemade cams, Sungam has taken a fall onto one of my homemade cams, I think making and using your own gear is fine as long as you know what you are doing. The problem here is that the OP has shown that he really doesn't know what he is doing.
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jt512
Oct 25, 2010, 4:39 PM
Post #38 of 101
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kennoyce wrote: seatbeltpants wrote: acorneau wrote: Khoi wrote: ozoneclimber wrote: OK....... The obvious question:
Why not just use tubular webbing and a water-knot? You, and everyone else, know that it is tried and true. Why complicate things when you don't have to? -B gthomann I'd really like to know your answer to this. Because he wants to make his own PTFTW's. Why did some folks make a cam for the Lab cam contest? Curiosity, perhaps? curiosity is cool - but how many of those who made cams for the contest actually climbed on them? steve I've climbed on homemade cams, Sungam has taken a fall onto one of my homemade cams, I think making and using your own gear is fine as long as you know what you are doing.
The problem is, as research has shown, people who don't know what they are doing, don't know that they don't know what they are doing.
Jay
(This post was edited by jt512 on Oct 25, 2010, 11:20 PM)
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ClimbOn68
Oct 26, 2010, 12:32 AM
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Jay, your reply is FUNNY AS HELL! Soo True!
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dynosore
Oct 26, 2010, 1:06 AM
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If you want a couple pull tested PM me. I can throw them on the Instron.
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rockvoyager
Oct 26, 2010, 1:09 AM
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Several years ago I had a friend sew a twenty foot piece of 1 inch webbing together with 2 square boxes and with an x in the middle of the boxes. I cinch tied this to a telephone pole and then hooked the other end around a 2 inch hitch ball on my truck. For several minutes I tried to pull it apart. When I couldn't break it with a static pull I backed up about 2 feet and nailed it pretty good. Still did't break. after several tries I finally gave up because I was starting to bend my back bumper.
Having said that, I use store bought slings. There're cheap and dying would ruin my day.
Brad
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jt512
Oct 26, 2010, 1:59 AM
Post #42 of 101
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rockvoyager wrote: Several years ago I had a friend sew a twenty foot piece of 1 inch webbing together with 2 square boxes and with an x in the middle of the boxes. I cinch tied this to a telephone pole and then hooked the other end around a 2 inch hitch ball on my truck. For several minutes I tried to pull it apart. When I couldn't break it with a static pull I backed up about 2 feet and nailed it pretty good. Still did't break. after several tries I finally gave up because I was starting to bend my back bumper.
Therefore, homemade slings are safe. Moreover, two box-X stitches are as good as 5 bartacks.
QED.
Jay
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kennoyce
Oct 27, 2010, 12:51 AM
Post #43 of 101
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jt512 wrote: kennoyce wrote: seatbeltpants wrote: acorneau wrote: Khoi wrote: ozoneclimber wrote: OK....... The obvious question:
Why not just use tubular webbing and a water-knot? You, and everyone else, know that it is tried and true. Why complicate things when you don't have to? -B gthomann I'd really like to know your answer to this. Because he wants to make his own PTFTW's. Why did some folks make a cam for the Lab cam contest? Curiosity, perhaps? curiosity is cool - but how many of those who made cams for the contest actually climbed on them? steve I've climbed on homemade cams, Sungam has taken a fall onto one of my homemade cams, I think making and using your own gear is fine as long as you know what you are doing. The problem is, as research has shown, people who don't know what they are doing, don't know that they don't know what they are doing. Jay
Great point as usual Jay. I certainly wasn't trying to say that this dude knows what he is doing (in fact based on his comments I believe that to be entirely untrue). I was merely pointing out that people do climb on homemade gear (not that I'm advocating doing this).
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gmggg
Oct 27, 2010, 2:51 PM
Post #44 of 101
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russwalling wrote: In reply to: 2.) Your stitches are really sloppy. A bartack is just a really tight zig-zag stitch but it it should be tight and ordered. You might try going slower when stitching or maybe your machine has a buttonhole setting. You also might try adding some appropriate adhesive between the webbing prior to sewing so that the piece is easier to handle. A bartack is NOT just a really tight zigzag. There is more to it than that. (note to self: do not feed the trolls)
Bump.
Still wondering what difference there is between the two stitches, couldn't find much in my brief research on the topic.
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gthomann
Oct 29, 2010, 3:08 PM
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Here are some results from initial testing. I have been using the loops I sewed in top rope setups but that isn't much of a test since the forces are so small. My CRV needed an oil change and John the garage owner is also a climber and of course I was showing him the webbing. So we decided to try lifting the back end of his truck. We tried first with the piece of webbing that only had 40 stitches. It lifted the truck quite a ways but then of course failed. So then we tried one of the "production" loops. The enclosed picture shows the setup with the back of the truck off the ground. The sewn loop is at the bottom connected to a quick link and the tied loop at the top goes to the caribiner. The photo is not very good; I did not have my tripod along and there was no way I was going to get in very close. We lowered the truck and inspected the equipment. The caribiner must have been bent a little as it no longer worked quite right.
After the lift test I photograped the loop as seen in the second picture. The stitching does not seem to have been stressed. You can see that the knot is pretty tight on the loop at the other end. I tried to undo the know with a marlin spike but I can't even get it started. The other small piece of webbing is what is left of the 40 stitch samplel.
Maybe it takes a 1000 pounds to lift the back end of the truck. John and I have already decided that at the next oil change we will try to lift the front end. I will take a tripod so we can get the camera in a little closer while we stand back.
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slings3.jpg
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jt512
Oct 29, 2010, 3:43 PM
Post #46 of 101
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gthomann wrote: Here are some results from initial testing. I have been using the loops I sewed in top rope setups but that isn't much of a test since the forces are so small. My CRV needed an oil change and John the garage owner is also a climber and of course I was showing him the webbing. So we decided to try lifting the back end of his truck. We tried first with the piece of webbing that only had 40 stitches. It lifted the truck quite a ways but then of course failed. So then we tried one of the "production" loops. The enclosed picture shows the setup with the back of the truck off the ground. The sewn loop is at the bottom connected to a quick link and the tied loop at the top goes to the caribiner. The photo is not very good; I did not have my tripod along and there was no way I was going to get in very close. We lowered the truck and inspected the equipment. The caribiner must have been bent a little as it no longer worked quite right. After the lift test I photograped the loop as seen in the second picture. The stitching does not seem to have been stressed. You can see that the knot is pretty tight on the loop at the other end. I tried to undo the know with a marlin spike but I can't even get it started. The other small piece of webbing is what is left of the 40 stitch samplel. Maybe it takes a 1000 pounds to lift the back end of the truck. John and I have already decided that at the next oil change we will try to lift the front end. I will take a tripod so we can get the camera in a little closer while we stand back.
So you've been toproping on slings that may be have less than 1/5 the strength of a normal sling. You must be proud.
Jay
(This post was edited by jt512 on Oct 29, 2010, 3:45 PM)
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spikeddem
Oct 29, 2010, 3:48 PM
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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.
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Rudmin
Oct 29, 2010, 4:08 PM
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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.
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dynosore
Oct 29, 2010, 4:14 PM
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Are you guys smoking crack? You think a full size truck is that light haha. Weight distribution is around 55/45 front/rear in a full size pickup. That truck weighs at least 5000 lbs. That means the back end "weighs" at least 0.45*5000 or 2250 lbs. 10kn minimum. That's for a empty, 2wd 1/2 ton. It's probably even heavier.
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bigo
Oct 29, 2010, 4:26 PM
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jt512 wrote: So you've been toproping on slings that may be have less than 1/5 the strength of a normal sling. You must be proud. Jay
I don't think his 'tr quality' sling failed. He is calling his homemade sling with more stitches the 'production' sling. The one that failed is a 40 stitch joint that I think he was testing to try and get a strength per stitch from.
While I enjoy 'do it yourself projects', sewing your own slings seems like a strange one to take on. High risk - low reward.
gthomann wrote: Maybe it takes a 1000 pounds to lift the back end of the truck.
Not sure how comfortable you are doing a little math, but if you found the center of gravity of the truck, you could derive a pretty good estimate of how much load you are putting on the sling using static beam analysis. The center of gravity of the truck is the balance point.
force = (dist_front_tire_CG/dist_hitch_CG)*truck_weight
edit: others beat me to the CG...
(This post was edited by bigo on Oct 29, 2010, 4:27 PM)
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I ain't! 
