Simple webbing pull test

[JeffGu]

Ok, I looked that RE Enforcer up... 4500 lbs. / 20kN so that's pretty close. Only $800 so right there in the pocket change price range. I'll empty all my change out of that peanut butter jar I use for emergency beer funds...

 

[JeffGu]

Couldn't a scale rated to 1000 lbs be incorporated in a 1:5 MA set up so that a reading on 1000 translated to 5,000 lbs of pull on the test piece?

There you go... that would be a lot less money! That $90 one I linked would probably get you close enough. The numbers wouldn't be real accurate, but that shouldn't matter too much... it would still tell you which stitching techniques and whatever were the strongest or weakest!

 

[FreeFallin]

Breaking load for 1" climbing spec webbing is actually 4,320# if my stitching pattern can withstand that then I would call it a sucess. That's right at 19kn.

The real end goal here being to design a stitch pattern that will hold consistently longer than the webbing it's sewn into.

 

[JeffGu]

Well, I think you can throw a setup together for a couple hundred bucks that would give you all the info you need for awhile. Once you have it all narrowed down to your best work, then you could always pay to have a few broken by TreeStiffy.com or somebody. A big come-along with steel cable should keep the measurements fairly consistent. Rope would stretch too much and throw your readings off.

Keep at it, man... let us know what you come up with.

 

[FreeFallin]

So right now with the $90 scale, my current 2 ton come-a-long. And a 4:1 MA rig that can handle 4k total I could break stuff myself.

I would still need to tackle getting myself out of the line of fire for any flying bits, but that shouldn't be too hard.

 

[Pelorus]

"I am using #67 T70 bonded nylon thread..."

I betcha you are not!!!

edit- am surprised you aren't using size 69 DaBond polyester instead of nylon.

 

[JeffGu]

Ahh, yes... 69... da bondage... nylons and leather... reminds me of those days at... wait a minute... what the hell are you talking about, Dave?

 

[Pelorus]

I dunno, Jeff.
Reckon V-69 has more cachet than some mysterious #67.

 

[Pelorus]

After much cajoling on my part, managed to get the wifey to make some chocolate rice crispy squares.
Ingesting some has awakened me from a semi comatose state.

 

[FreeFallin]

"I am using #67 T70 bonded nylon thread..."

I betcha you are not!!!

Are you questioning the integrity of my strings?!?

I wanted to stick with nylon on nylon to equal fiber strength as much as possible, I could sew with thinner but much stronger Kevlar thread but it would slice the nylon webbing under load and has the potential to snap easier when shock loaded. The upside would be that the webbing would be bullet proof

 

[FreeFallin]

Hahaha, just caught that, you are correct it is #69

 

[FreeFallin]

Please deliver these chocolate squares that you speak of, that I too may shed my comatose.

 

[JeffGu]

No rice crispie squares, but I did fix me a cup of hot chocolate... I don't want you guys getting ahead of me in the weight gain department, and beat me in the Fat Dads Tree Stress contest.

 

[Brocky]

For the stitch pattern, have you seen Smith and Padgett's book,On Rope for their recommended strongest pattern?

 

[Pelorus]

Have you tried using V-92 thread with a size 19 (120) needle in your machine?
I'm curious what model machine you are actually using...hoping it was manufactured pre-1970's...

 

[FreeFallin]

For the stitch pattern, have you seen Smith and Padgett's book,On Rope for their recommended strongest pattern?

It's on my short list but I haven't got it yet. Wish they would publish it digital, my brain wiring does much better reading on a screen.

Didn't they recommend criss crossing straight lines?

 

[Brocky]

No, long zigzags, just one continuous pass.

 

[FreeFallin]

Have you tried using V-92 thread with a size 19 (120) needle in your machine?
I'm curious what model machine you are actually using...hoping it was manufactured pre-1970's...

I am using a 120 needle now, a lot of what I read said V-92 would be too grabby going through the needle so I haven't tried it yet.

I used to have an old cast Singer but regretfully let it go 20 years ago. Now I have a White, I need to check the model/year but it is probably not pre 70s.

 

[FreeFallin]

No, long zigzags, just one continuous pass.

So - using a straight stitch setting and then zigging and zagging up and down the material you are sewing in one pass without cutting and restarting, is that correct?

 

[Brocky]

Yes, that's it.