conflicts of interest, stitches, and eggs

Discuss vertical caving, equipment, & techniques. Also visit the NSS Vertical Section.

Moderator: Tim White

Postby hank moon » Jan 8, 2006 3:44 pm

Scott McCrea wrote:In the new posted out-of-print Nylon Highways, I found an article on sewing with stitching awl. It's in #17, Dec '83.


Interesting article...lots of "how-to" and theory, but no test data of sewn joins. Oh well.

hank
User avatar
hank moon
NSS Hall Of Fame Poster
 
Posts: 610
Joined: Sep 7, 2005 9:52 am
Location: Salt Lake City
  

Postby knotty » Jan 26, 2006 12:49 pm

My personal experience with sewing with nylon thread(including spider line)is that it cuts the fabric. I've made backpacks, sleeping bags, tents, sit harnesses, dog backpacks, gators,and so on. Ive experienced failure under stress when packs are overstuffed, tents in high winds, and I personally have given up on nylon thread. As the fabric gets older and starts to degrade, it tears at the thread(even when new but more when it ages). I prefer now to use quilting thread and have had no problems with the thread cutting the material.
Hand sewing has worked well for emergency repairs but for me it would take way to much time for larger projects. Truthfully, I don't mind risking my life on something I've sewn(I trust my work) but I wouldn't allow others to use. Despite the liability issue, my biggest fear is that others may get hurt. I've seen first hand what a serious fall can do and I don't need any more memories like that. This is just my opinion based on my experience and we all know what opinions are like. We all have one
knotty
Infrequent Poster
 
Posts: 22
Joined: Jan 18, 2006 11:33 am
Location: Pocatello Idaho
  

Postby Scott McCrea » Jan 26, 2006 3:22 pm

knotty wrote:My personal experience with sewing with nylon thread(including spider line)is that it cuts the fabric. I've made backpacks, sleeping bags, tents, sit harnesses, dog backpacks, gators,and so on. Ive experienced failure under stress when packs are overstuffed, tents in high winds, and I personally have given up on nylon thread. As the fabric gets older and starts to degrade, it tears at the thread(even when new but more when it ages).

Hmm, that sounds strange to me. The majority of sewn stuff in the outdoor industry is stitched with nylon thread. When fabric rips at a seam, it usually means either the material is too weak/old, the stitch length was too short (too many stitches per inch and the needle 'perforated' the material), the thread was too strong (some say the thread should break before the material tears), or the needle is cutting the material instead of pushing a hole between the weave of the material. Or there are other possible causes.

Of course, harnesses and stuff sewn out of webbing is a different story. The thickness of the webbing lessens the effect of these causes. It's very forgiving.

In order for nylon thread to cut the material it is sewn in, there needs to be some movement--a sawing action, indicating a poorly sewn joint.

I prefer now to use quilting thread and have had no problems with the thread cutting the material.

I'm not familiar with quilting thread. What's the difference?

Knotty, please don't think I'm passing judgment on your sewing skillz. Just trying to help by letting you and others know what I think. My opinions. :grin:
Scott McCrea
SWAYGO
User avatar
Scott McCrea
Global Moderator
 
Posts: 3198
Joined: Sep 5, 2005 3:07 pm
Location: Asheville, NC USA
NSS #: 40839RL
Primary Grotto Affiliation: Flittermouse Grotto
  

Postby knotty » Jan 27, 2006 10:09 am

perhaps ur right about my skills when it comes to sewing. no offense takin.
knotty
Infrequent Poster
 
Posts: 22
Joined: Jan 18, 2006 11:33 am
Location: Pocatello Idaho
  

Postby Scott McCrea » Jan 27, 2006 10:18 am

So, tell us more about quilting thread.
Scott McCrea
SWAYGO
User avatar
Scott McCrea
Global Moderator
 
Posts: 3198
Joined: Sep 5, 2005 3:07 pm
Location: Asheville, NC USA
NSS #: 40839RL
Primary Grotto Affiliation: Flittermouse Grotto
  

Postby Geary » Jan 27, 2006 10:25 pm

Hank,

I wasn't trying to ignore you related to your request on data, I've just been buried with stuff. Regarding the article on strengths of webbing, if I remember correctly, John Standard, a very well known rock climber did some research on strengths of webbing using hand stitched webbing using a speedy stitch er. He broke the webbing at a bend and not at the stitching joint. I know that it was published in Off Belay around 1975 but I gave all of my old climbing mags away a couple of years ago. I assume that you could go to the AC library in Golden and find them or maybe a really good university with an outdoor rec program. As far as I know, I've never seen any of these old mags on line.

Regarding data from stitching breaks, I did most of my work at Vanderbilt University with Jerry Horne who was working as a technician in the civil engineering lab. I ran a number of tests on the machine and broke a number of different stitch patterns, webbing, thread type etc and got results that were similar to what other folks have reported. I should have published the data but got busy doing other things. I still have the webbing and printouts in the basement but I don't know if I still have the notes available. I've been talking about rerunning some of these tests to try and isolate the variables. I do know that I got to the point that I could predict the strength of stitching on new webbing pretty closely.

Too much to do but too little time.

Gary Schindler
Geary
Infrequent Poster
 
Posts: 22
Joined: Nov 1, 2005 9:25 pm
Location: San Antonio, Texas
Name: Geary Schindel
NSS #: 15827F
Primary Grotto Affiliation: Bexar Grotto
  

Postby hank moon » Dec 1, 2007 2:51 pm

Geary wrote:Regarding data from stitching breaks, I did most of my work at Vanderbilt University with Jerry Horne who was working as a technician in the civil engineering lab. I ran a number of tests on the machine and broke a number of different stitch patterns, webbing, thread type etc and got results that were similar to what other folks have reported. I should have published the data but got busy doing other things. I still have the webbing and printouts in the basement but I don't know if I still have the notes available. I've been talking about rerunning some of these tests to try and isolate the variables. I do know that I got to the point that I could predict the strength of stitching on new webbing pretty closely.


Can you tell us how the joins were made? By hand with an awl or needle or using a sewing machine or...?

hank
User avatar
hank moon
NSS Hall Of Fame Poster
 
Posts: 610
Joined: Sep 7, 2005 9:52 am
Location: Salt Lake City
  

Previous

Return to On Rope!

Who is online

Users browsing this forum: No registered users