hello, forum members.
i am often seeing the use of stitching through the midsole in various ways so i am getting confused regarding this.
is this generally a practical thing or is it mostly for aesthetic purposes? for instance, most sneakers have it across the front, while others may have it all along the midsole (like with the nike dunnks). other times, the stitching is strictly on the edge of the protruding rubber sole, mainly in oxfords, dr. martens, ect. in some rarer cases, like with the AJ 18, there is stitching at the bottom of the soles.
are the manufacturing methods used the same in all these cases? at first, i assumed that the stitching was to hold together
the upper and midsole, for extra reinforcement. but what about the oxfords, or the 18s? how deep does/can the stitching go? what’s the hardest
material possible that you can pierce, say a TPU or carbon fiber shank even? also, is it expensive to do this? ie. if i thought it looked cool, could i choose
to add this feature without adding too much cost?
i think that’s about it for now. i kno it’s a bit tedious but please bear with my slow learning curve. i’ve mostly been learning by studying patents, books, and all the cool stuff that’s available online but i couldn’t really find a comprehensive answer regarding this. oh well, it’s nice to meet the community finally.
You question actually covers a few different things.
normally, you dont stitch through a midsole (like a CM EVA midsole) but can stitch through an outsole.
a toe bumper stitch is a common version of this used on things like classic tennis shoes, or indoor soccer shoes. It is called an Aryan Stitch to my knowledge, but im not sure about the spelling. This is done after the outsole is cemented to the upper (assembly) and is done with a special stitching machine with a heavy needle and thread.
This is also the same process used on an AF1 sidewall which is a rubber cupsole.
Stitching through the bottom of the outsole is common for some type of shoes like soccer shoes, in which case the process is similar and goes through the PU or TPU outsole.
As well, sometimes stitching is done in a decorative manner through either the rubber outsole before cementing to a CM EVA midsole or upper or through a piece of leather or other material which is then cemented to the outsole or the rubber sidewall.
I cant find any good pics at the moment for reference, but if its not clear im sure i can add some tomorrow when Im back at work.
As for what material you can stitch through I think any kind of leather is OK, as is TPU is you make a reduced section nominal thickness in the area you want to stitch (also to use as a guide by the stitching operator), but Im pretty sure you cant stitch through carbon fibre as it would crack and splinter.
Cost isnt really much of an issue. Like any other stitching operation, it does add a step and some small cost to the production, but there isnt anything particularly expensive about the process or materials so really shouldnt affect the cost in a measureable way unless you are counting every fraction of a penny and second of construction time.
Hope this helps,
R
Rich is right. The Aryan stitch like on classic shell tops and such sometimes use a hooked needle to get around and though the different layers.
As far as what materials can be used, I have seen some Bike shoes that have stitched through carbon fiber, but never really seen it happen in person. I’m assuming that some of the stitching is done while the fiber material is still somewhat pliable.
Of course, you could also use a different material with a “carbon fiber-esq” finish to be stitched through.
thanks for the insight! i had some follow up questions, though they have more to do with stitching/embroidery in general. for instance, are there different stitching terms in footwear or are they the same as the ones that are seen in reg. fashion industries? there’s this stitching that is prominent on the converse wade shoe (it has like a zig zag pattern ) but don’t know what it’s called and yet i’ve seen variations of this in clothing and such. even the new jordan 22 has a similar pattern that i like. actually, maybe you guys could suggest a good website? i never really thought about these things on my designs until things started to get too repetitive and stale.
stitching is different than embroidery.
Im not that familiar with stitching applications on textiles, but would assume its pretty much the same.
In general, forfootwear, there is either single or double (and even tripple) needle stitching which gives you 1, 2, or 3 rows of stitches.
Stitching is generally done by an operator on a sewing machine, see here-
http://pullover.blogspot.com/2006/02/football-boot-production-stitching.html
but, can also be done with a computer controlled machines for more decorative stitching patterns such as on the vamp of a football shoe or the details on the Jordan 22 as you mention.
When you start to get into the details there are tons of applications you can use to keep things interesting. stitching, embossing, HF welding, printing, folded edges, reverse seams, different materials, perfing, laser etching, overmolding, embroidery, etc.
R
Stitching through the sole can sometimes be used for comfort footwear, for example on corner stitched shoes. Clarks use this construction quite often, Airwalk also used it some years ago for a range of leather shoes, it now seems that Simple and other comfort brands use this construction most often.
Although this construction is often seen as quite frumpy, I have used it on fashion shoes to great effect.
There are also other comfort constructions, such as Stitchdown and Sancrispino, where the upper is attached to the insole board, which is then bonded to the outsole.
Stitchdown - the upper is raw edged
Sancrispino - the upper is folded around the insole board them stitched
Corner Stitched - the upper is folded around a ridge that runs the whole way around the outsole then stitched through
Often when used on sneakers, the stitching is there to help keep the upper attached to the sole, especially on cup soles, where foot flexing over time can cause the sole bond to deteriorate.
Sometimes, the leather you use, if it has a high oil content (like alot of the Prime Tanning leathers, for instance, you may need to stitch the sole to the upper as it would be difficult to bond with glue alone.
As for cost, well, it depends, the labour charge for difficult constructions isn’t as high as it used to be in Europe, but you have to check the factory has the machinery, in order to stitch onto the sole, there are diffierent types.
thanks everybody. very appreciated. oh, and props on the blog.