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Big Wall Index => Big Wall Forum => Topic started by: slabbyd on March 04, 2010, 09:57:47 am

Title: Sewing webbing - tips?
Post by: slabbyd on March 04, 2010, 09:57:47 am
Hey all.  I know there are a number of people on this board sewing up their own gear and I'm looking for advice on how to sew webbing together.

I've got an old Bernina sewing machine.  While not "industrial" it's certainly a bit sturdier looking that a lot of what you see at the stores.  When you pop the top off it's all metal gears and cams and stuff.  Previously I've had no problems stitching together fairly thick flat nylon webbing using standard polyester thread and a size 16 denim needle.  Of course that thread isn't particularly strong so I went out and got some bonded nylon thread in a 69 as well as a 46 weight and some size 18 universal needles.  

So with the goal of making a pair of 3-step subaiders out of 3/4" webbing to complement my yates.....

Last night I tried stitching webbing together with the nylon thread and it was a miserable failure.   Basically the top thread punched through just fine but when it grabs the loop of bottom thread that just sort of mashes up against the bottom of the webbing rather than pull up through it.  Seems like there was to much friction between thread and webbing for it to pull through.  I tweaked the tension on both threads,  reducing it on the bobbin and cranking it up on the top thread which helped..sort of.  Still it was a bit of a disaster.

 So I'm thinking I need a bigger needle or thinner thread.  Maybe a different type of needle?  (ball, denim, leather???)  Soak the bobbin in water prior to use?  

Any advice or similar expereinces (particularly success stories) is much appreciated.


Title: Re: Sewing webbing - tips?
Post by: slabbyd on March 05, 2010, 09:10:38 am
Well thanks for nuttin.

To answer my own question,  should anyone ever do a search on this topic,  it's apparently all in the needle.  Get a top stitch needle.  It's sharper point slides through the webbing easier and the longer thread hole apparently improves its ability to oull the bottom thrad up into the webbing.  It made all the difference.  Also loosen up the bobbin tension and increase the tension on the top thread.  Starting and finishing the stitch by manually turning the flywheel seems to make it cleaner as well.
Title: Re: Sewing webbing - tips?
Post by: mungeclimber on March 05, 2010, 12:54:12 pm
thx for the topic and research in that case!



Munge "no cross stich skills whatsoever" Climber
Title: Re: Sewing webbing - tips?
Post by: xtrmecat on March 08, 2010, 08:31:11 am
  I would also like to say thank you for this tidbit. I just got my first industrial machine, a Thompson, and any knowledge will save me tons of hard earned lessons. Gonna sew stitches on all my hooks and such, you know to keep the knots from coming loose.

Title: Re: Sewing webbing - tips?
Post by: slabbyd on March 08, 2010, 10:39:39 am
I finished up a sweet pair of sub-aiders over the weekend.  It's fun to make stuff when you can't actually get out.

Some more tips...particularly for people without a real heavy duty machine.

Flat webbing comes in varying densities and stiffness in the same width.  My sewing machine was easily able to sew the looser stuff and really struggled with the stiffer, denser stuff.  I was using 3/4" which supposedly is a denser weave in general than 1" and hence harder to sew.  1" tubular is easy to sew through. is an excellent, cheap and quick source for webbing and hardware.   Just talk to them in person and make sure your getting the looser woven webbing.

If your machine bogs down, hand cranking the fly wheel gives you the same results and will keep your motor from burning out.

Bonded nylon thread comes in varying thicknesses.  I was using someing called v46 which is thinner and weaker than the v69 or v92 that I bet most equipment manufacturers are using.  But my machine and the size 16 top stitch needle I mentioned above could handle it.  v69 and v92 require larger needles.

Tensile strength of threads
v46  6.8 lbs
v69  10.0 lbs
v92  13.3 lbs

Each stitch (composed of two threads) supposedly has a breaking strength of 1.8 * thread strength.  In my case 12 lbs.  For each webbing connection I generally ran 3 sets of 4 rows of 7 stitches.  Equals 1008 lbs of strength.  Even if thats off by a factor of 2 it's still plenty strong for lots of stuff.

Bounce tested the aiders nad they're still in one piece, so thats good...

Title: Re: Sewing webbing - tips?
Post by: YetAnotherDave on March 08, 2010, 02:47:21 pm
thanks for the needle recommendations - I've been using jeans needles, and have had wildly different results with different needles without really understanding why.  I'll get some 'real' topstitch needles and see how they work.

My week's sewing project was making simple daisies to sew into my new piggies - still had to use the speedy-stitcher to attach them tho. 

Why don't manufacturers put more gear loops in pigs?  My big bag is the only one with any, it'd take almost no work to add them early in production...
Title: Re: Sewing webbing - tips?
Post by: Chad on March 09, 2010, 10:16:30 am
One resource you might want to check out is the book:

by Bruce Smith & Allen Padgett

ISBN 978-1-879961-05-0

P. 239 & 240 are exactly relevant to what you are doing. There is also a pictorial chart showing the relative strength of different stitching patterns/methods. Pretty interesting, the bar tacks we get on our sport climbing quick draws and trad 60cm/120cm sewn slings have a relative strength of 66%, while the stitching pattern used for heavy duty applications has 100% relative strength.

Here's an example of what the heavy-duty stitching pattern looks like. It's stronger because the sewing incorporates both the warp and woof of the webbing material rather than going more in line with it:
Title: Re: Sewing webbing - tips?
Post by: YetAnotherDave on March 09, 2010, 12:55:05 pm
The solution most climbing gear makers use is to add a few more tacks, because you can have a cheap unskilled worker running a bartacker, where it takes more skill/time to make neat stitches.

I worked at arcteryx when I was 18 (a really long time ago), and there was a pretty clear distinction between the climbers and the 'real' sewers.  You definitely wouldn't have wanted to climb on anything I sewed unless I was running a preprogrammed machine  :)

Thanks for the book reference,

Title: Re: Sewing webbing - tips?
Post by: slabbyd on March 09, 2010, 10:30:53 pm
Thanks for the tip Chad.  I picked up the book at the library near my work today and like you said it's exactly relevant.

Wish I had read this before I made up some aiders as I used what is one of the weakest stitches!

To provide a little more detail from the book to those interested....

Warp are the threads that run across the webbing.  Woof are the threads that run lengthwise.  The strongest stitches are ones that cross both warp and woof, i.e. diagonal

The strongest stitch pattern (and what might be the easiest to sew with an underpowered machine) is a single series of long but very narrow zigzags sewn parrallel to the length of the webbing.  To quote the book

"The overlap should be three times the width of the webbing being sewn.  The number of passes should be nine per inch of width of webbing.  If 1 inch of webbing is being sewn there should be three inches of overlap and at least nine passes"

In other words imagine starting on the edge of the webbing at one of the overlap and sewing a very slightly diagonal line up to the other end of the overlap, then raising your presser foot (needle down) spinning the webbing around about 170 degrees, sitiching back down to the end and repeating until you reach the other side of the webbing.

Interestingly the book has patterns and suggests sewing a lot of the jumaring gear used by cavers.
Title: Re: Sewing webbing - tips?
Post by: mungeclimber on March 09, 2010, 10:44:22 pm
isn't there a route called warp and woof?

if there isn't, there should be.