Does hand stitching provide superior durability/longevity to machine stitching?

[Spyros]

I'm sure it's been discussed before but there's so many discussions on hand stitching that I couldn't find this specifically. 

The reason I'm asking is because people are asking me, and I just repeat what I read on the internet:

a) Stitching by hand is superior to machine stitching, there is a significant difference in longevity and durability.

b) There is no machine that can do saddle stitching like we do by hand: pass two needles from the same hole from opposite directions, and repeat with the next hole.

But then I realised that I don't actually know either of those two things as a fact, I was just parroting things posted on the net by people I don't know.   

So I decided to ask the experts 

Thanks in advance

Spyro

Edited May 27, 2020 by Spyros

[Spyros]

I guess what I'm asking is, does this make a difference in real life in everyday items like wallets and bags etc?

And isn't there a machine out there that can do the same stitch as the hand sewn saddle stitch below?

 

Edited May 27, 2020 by Spyros

[chrisash]

In many cases the hand sewn item has used thicker thread typically 0.6 or 0.8 mm like tiger thread,  but if  linen thread is used i think it has far less strength than say tiger

On the other hand #277 and #346 are close to or slightly above 0.6mm but i have no knowledge of the breaking strain of tiger thread v 346

 

Edited May 27, 2020 by chrisash

[Matt S]

For most everyday goods it doesn't make a difference... but it is a cool selling point for many people -- like hand cut blind dovetails on a piece of furniture. Nothing wrong with that in the right context.

Correctly and consistently saddle stitched seams, using exactly the same thread and SPI, are probably stronger than lockstitch sewn seams but that's usually not the reality. IMHO most of the durability of a saddle stitched seam is because of using linen thread with a decent coad (thread wax) formulated to lock stitches together (beeswax doesn't count!). Punched holes, synthetic thread, slippery thread wax, ridiculously high SPIs... throw any of these into the mix and any actual physical benefits to saddle stitching go out the window (again IMHO, I have no statistical or scientific data to back up this opinion, just experience and vicarious experience).

I figure that lockstitch and saddle stitch are different, that's all -- like rivets vs. sewing. You just design and make your goods around whatever technique you want to/can afford to use, which you can only do when you understand the strengths and weaknesses of each method, and the item's intended use.

[chuck123wapati]

Your pic says it all. Hand sewn is in essence two separate stitches independent of each other so if one breaks there is still another. With a lock stitch there are two threads but they aren't independent of each other so if one fails both fail. That being said a good lockstitch is better than a poor hand sewn stitch and  a good hand sewn stitch is better than a poor lockstitch. IMO. The sewing machine was created to make sewing easier and faster not necessarily better but they are better than some can sew by hand in that every stitch has the same tension same spacing etc.

[Tugadude]

I think there's two issues going on.  One is the strength and the relative comparison of machine versus hand and the other is durability.  They are somewhat the same, but there is a nuance to it I think.  In my opinion, even if the hand stitching is equal in strength to machine stitching it still wins out because of the fact that there is no lock stitch.  So unless both threads break, the leather will still be held together.  Any break in a machine stitch will ultimately result in the leather coming apart.  It may take a while, but it will fail.  

I am unaware of any machine capable of producing a saddle stitch in the same fashion as that done by hand.

[BentleyLeather]

I think the experts above clearly answered things. 

Just to add to some of what I have seen as far as machine stitching goes:

A few weeks ago I repaired a really old (client stated 30 yrs old) safariland holster. The upper part of the belt loop stitching broke lose because it rubbed on the cylinder of the revolver. The rest of the holster was still rock solid. 

Same could be said of several other items 40+ yrs old. It was a matching wallet, sunglasses case, brief case and padfolio. A few of the items had a broken stitch or two but were holding up well despite being machine stitched. 

If the end user has access to a thread and needle or a lighter most likely the items could be repaired before complete failure.