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xclimber
Aug 24, 2003, 11:57 PM
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Registered: Jan 17, 2003
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Anybody ever do their own bar tacking? What kind of sewing machine would be required? Can you just use a rectangle with an "X" sewn to connect the corners or are there more specific patterns? What size and type of thread should you use...?
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petsfed
Aug 25, 2003, 2:02 AM
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Registered: Sep 25, 2002
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Indeed. Enough research has shown me that 1) the x stitch isn't very common, or very strong. 2) you need upholstery thread (or heavier) to deal with abrasion and what not. 3)bar tacking by hand is tedious work, easy to screw up, and best left to professionals. 4) 1(one) bar tack will fail at around 30 pounds, 2 (two) tacks somewhere between 90 and 150 pounds, and 3 (three) I've not had the chance to test yet.
I haven't, nor will I, stitch anything that I expect to save my life. I'll stitch aider slings, but I won't do daisy chains. I'll stitch straps for a portaledge, but I won't make a harness. Understand? If I might fall on it, then I won't stitch it myself.
As an aside:
Once, a long time ago, my mother stitched daisy chains for my father, and she never slept when he was out climbing until he threw those out. This from a woman (my mother) who owns and operates an industrial sewing machine professionally.
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pirate
Aug 26, 2003, 10:00 PM
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Registered: May 12, 2003
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Well do your homework before you sew thats for sure.
now as for myself yeah i sew my own gear , have for years (although often now I buy stuff as its often cheaper and now I can often buy what I want (that was not always the case in days gone by).
the last things Ive sewn were some gear for Aiding ie sewn slings for 20 of my BD peckers used 9/16 webbing Nylon Upolstery thread and a series of 8 bartacks.
minimum of 35 stitches per tack each tack continues to the next.with a jump stich and rotation of sling (stitches always sewn forward).
Now I sold my other 2 machines so I had to borrow my moms Machine (a kenmore)
Since these stitches should be sewn slow as to keep the integrity of thread (fast stitching could melt the thread) I turned allot of stiches by hand assisted with light peddle control (yes it takes a while)
I made several others to test and all have failed in places other than the stitching (particularly where the sling breaks over a small edge as in the pecker hole) BTW I used a comparable shaped hole on a plate of chromoly steel hooked to 1/2" steel cable running to a truck to induce the shock load (with precaution to avoid a flying cable)
Anyway the gist is yes you can sew on a home machine bar tacks but you put yours and possibly others lives in your hands so make sure you know what you are doing.
And as I said there is almost nothing you cant buy now so there is very little reason to sew your own gear (unless making prototypes as I do)
Its rare to be able to make it for cheaper than you can buy it especially if you factor in all the labour etc (but still can sometimes be worth it)
Just be safe and if its load bearing buy it if you can you will climb more confidently above a commercial piece then one you experimented with.
:wink: cheers
Oops forgot to mention if you sew heavy thread on webbing etc you need to have the proper needle and adjust all your thread tensions (you will have to turn the tension up quite high on both needle and bobbin threads)
If you dont get your tension right it will look like poo and will be as strong as poo (not what your after)
anyway I just wanted to add that so you dont end up with a birds nest.
Note If your thread and or needle is not strong enough you will keep breaking them with your tension set as high as it needs to be.
Hope this helps cheers
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wlderdude
Aug 28, 2003, 5:01 PM
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Registered: Aug 8, 2002
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I used to sew my own gear.
It is cheaper and easier to buy it, though. I wish I hadn't watsed my time and money.
If you are protoyping some new idea, it may be worth it, though.
Here is what I learned.
The zig zag stitch on a home sewing machine that resembles a bar tack is NOT stronger than the webbing. The big box with an X is no good, either.
There is a stitch that can be done on a home sewing machine that is stonger than the material. It is the stich used in industial applications where loads FAR exceed anything we deal with. This stich is done with a straight stitch, so industrial machines work best. It is tedious, takes a lot of thread and a lot of patience. The geometry of what you want to sew will limit where it can be done. However, it does make stitches that exceed the strength of the webbing.
I sugest you consult with someone in person who is experienced in upolstery and heavy sewing applications before trying it. The stitch is basically putting in 2" lines of tight stitching back and forth in the dirrection of the force. They should be close together without overlapping. Sort of like an acordian pattern.
Look at some heavy duty industial staps and you will probably find this stitch in use.
Good luck.
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debsanders
Aug 28, 2003, 5:47 PM
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Registered: Feb 4, 2003
Posts: 173
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My husband the jumper in the family has sewn a few pieces for us. We agree it is cheaper to purchase unless you are rigging something special. He uses the parachute manufacturing specs. Not sure how he got the manual but if you are interested post back and I'll get the info.
The manual is full of stiches, thread strength, web spec, etc. . .
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