bcraig Report post Posted October 6, 2019 Are there any preferences to using a Polyester Versus a Nylon thread for stitching a holster ,durability,ease of use ,stitch appearance ? I am liking the appearance of the larger thread from what I have seen and am wanting to use a Round thread #346 or larger . Will be using 5 SPI and a Osborne AWL to Hand stitch with 7-8 ounce Veg Tan Leather. Quote Share this post Link to post Share on other sites
wizard of tragacanth Report post Posted October 6, 2019 This could be relevant to your purchase if you hand sew. #346 sounds like machine thread, which I know nothing about. I believe that most, if not all machine thread is left-twist. I also believe that if you sew right-handed with a left-twist thread, it has a tendency to "unravel" as you sew. I could be totally wrong about this. Some one will straighten me out on this, I hope... nick Quote Share this post Link to post Share on other sites
Mark842 Report post Posted October 6, 2019 As the last responder stated 346 is a machine thread size and machine thread will not work as good for hand sewing as thread specifically made for it. That being said, To answer your question both bonded nylon and bonded polyester would look the same on the finished product. The difference between the two is that bonded nylon is stronger but not UV resistant. Bonded polyester is UV resistant. My preference is always bonded polyester as my product is an outdoor product that will see a lot of sun. Quote Share this post Link to post Share on other sites
Old Coach Saddlery Report post Posted October 6, 2019 I use poly. And I have hand sewn with my machine thread. I am right handed and have not had any trouble with unraveling. Quote Share this post Link to post Share on other sites
fredk Report post Posted October 6, 2019 (edited) 2 hours ago, wizard of tragacanth said: I believe that most, if not all machine thread is left-twist. I've never noticed the twist of any of my threads. . . . . . . and I ain't gonna go looking at them now! 2 hours ago, wizard of tragacanth said: I also believe that if you sew right-handed with a left-twist thread, it has a tendency to "unravel" as you sew. Never heard of this. Never happened to me, To the OP. I use Poly as that is what I can get in colours to suit / match my leather colours. The Poly I buy is flat in section. I like the way it lays flat when pulled snug. ~~ this was my 1500 posting! Edited October 6, 2019 by fredk Quote Share this post Link to post Share on other sites
JLSleather Report post Posted October 6, 2019 I don't see a visible difference - meaning they may not "match" side by side, but you'd be hard pressed to look at a thread and say it's nylon or poly (here come the "pros", who of course CAN tell, and also tell you which way you were facing when you sewed it). I recently saw a 3-ring binder I made in the 80's.. sewn with 4-cord NYLON thread. Holding up even better than I would have hoped. That whole thing about "UV resistant" MIGHT make a difference on boat tarps and car seats that will be in direct sunlight all day. On a holster, disregard that stuff. _________________________________ That said, it DOES sew a bit differently through a machine, though that's not the question HERE. Both are fine, but I notice that when I switch from one to the other, even though the sizes are the same the tension involved is a bit different. Not "worse" or "better", just different. Quote Share this post Link to post Share on other sites
bcraig Report post Posted October 7, 2019 Thanks to all,trying to learn as much as I can Quote Share this post Link to post Share on other sites
thefallguy Report post Posted October 8, 2019 Nylon probably has a little more stretch than polyester, but I doubt if anyone could tell the difference between them. I would consider waxed thread made for hand stitching if I were you. As a separate note, If you burn your thread ends when you tie them off, I would avoid polyester. This is an extreme example, but burning polyester shut down my dad's liver and nearly killed him before we figured what was going on. Long story short, a mislabeled roll of polyester webbing with no spec sheet cost thousands of dollars and [probably] years of my dad's life. We still use nylon almost daily, but polyester is a no go for us after that experience. Quote Share this post Link to post Share on other sites
wizard of tragacanth Report post Posted October 8, 2019 3 hours ago, thefallguy said: I would consider waxed thread made for hand stitching if I were you. This is a very good point that no one had mentioned. For hand stitching, you want to buy waxed thread or wax your own. nick Quote Share this post Link to post Share on other sites
Gymnast Report post Posted October 8, 2019 (edited) One other important diffence in material properties are creep or relaxation. With a long time load on the thread, the nylon thread will get longer and longer until it eventually breaks. This will not happen with a polyester thread. This may not be a bad thing for the nylon thread used for high load slings, because then the forces in uneven stiched parts will better be distributed to many threads of the seams. A good source of information on these materials are from rope users and manufacturers. One source can be found here:https://www.animatedknots.com/rope-materials#ScrollPoint Edited October 8, 2019 by Gymnast Quote Share this post Link to post Share on other sites