How to glue rubber to leather

[deboardp]

On 1/25/2024 at 12:05 PM, Mablung said:

Wow, that's thick.  Apprise us of how it feels on the foot. 

It is thick. but not as thick as what I made 50 years ago. I don't remember exactly what I bought, but I know the bottom was bend, and it was thicker than the top, which I have no idea what it might have been. A snatch-out-of-the-air-guess would be 12 ounce shoulder for the top and 14 ounce bend for the bottom, and 7/8 ounce horse hide for the straps. 12 and 14 is 26 ounces total. This current sandal is 10 ounce shoulder and 15.5 ounces of veg tan for straps and lower soles, for a total of 25.5 ounces. Because the sandal is so stiff - and that's without the rubber and heel - I will keep the shoulder for the top and move to two layers of 6 ounce luxury veg tan for the straps and two lower soles, for a total of 22 ounces total, or 3/8" (rather than existing 7/16"). It's not much thinner, but two lower soles are luxury veg tan, a supple leather, as opposed the Hermann Oak craftsman veg tan, which is firm. It might make the sandal more supple and less stiff.  I guess we shall find out!  

I'm keeping the top at 10 oz because when I tug on the strap to tighten the front strap, I don't want the topsole to bulge away from the midsole. I want it to be the most durable sole. The mid-, bottom- and gum-soles will add plenty of stiffness, putting the overall thickness at exactly 1/2".

[Tastech]

Deboardp. Here is a link to the material i would recommend. Its a consistent thickness material called microcell. It is soft, flexible , easy to cut and glue and is relatively tough. It comes in multiple colours , multiple thicknesses and multiple tread patterns . Not that expensive either  

 https://www.leffler.com.au/shop/shoecare-repair-orthopaedic/shoe-bag-repair/rubber-heeling-soling/rubber-soling-sheets/

 You must have a shoe repair cobbler close by . They don't have to be high end , Even a retarded one will be able to show you some options .  Cobblers are notoriously cranky buggers  so go in there on the premise of getting some soles on sandals ,but you want to think about options . They will show you some different types . Make sure you feel them to gauge the material for softness . 

Below is a vibram tapered sole with the heel ready to go .(recommended)

The other photo is various microcell .

Your options are too numerous to list or show . Its all about what you want the sandals to look and feel like . You can also incorporate a layer of cork below the top layer which over time will mold to the contours of the wearers feet . All decent shoes have a cork layer under the innersole . If you want a seperate heel cut one out and glue it on top of the sole .

Your sandals should be thus . leather upper sole (innersole ) ,cork midsole , And rubber or microcell or EVA bottom sole . Don't over do the leather thickness as this makes them to hard and uncomfortable .

Go to a few shops and study the anatomy of a sandal all are different but you will see some thing you like and you can incorporate that feature in your design .

https://www.ancient-greek-sandals.com/en/eur/mens-sandals

Note the different soles on some of these sandals . Only women can wear flat plain leather sandals , Men need some contour and some taper. Be prepared to experiment , and don't be discouraged by failures .You learn valuable lessons . The greatest glory in living is not never falling ,but rising when we fall .

Sorry for my long winded answers but i don't do things half assed . Balls deep or nothing .  

 

[deboardp]

7 hours ago, Tastech said:

Here is a link to the material i would recommend. Its a consistent thickness material called microcell. It is soft, flexible , easy to cut and glue and is relatively tough. It comes in multiple colours , multiple thicknesses and multiple tread patterns . Not that expensive either  

thank you! You've opened up a new world for me, the world of rubber soles. I'll work in a visit to a cobbler soon. apparently there's a hundred of them within an hour of my apartment. 

7 hours ago, Tastech said:

Go to a few shops and study the anatomy of a sandal all are different but you will see some thing you like and you can incorporate that feature in your design .

I studied sandals 50 years ago, and then again this past year and a half, and I haven't changed my mind about sandals. Both times, I came up with the same conclusions, which are that 1) sandals made by a size pattern ignore the specific skeletal architecture of the individual, instead opting for a one pattern fits all. Usually this pattern of straps results in the toes being pinched together, and general discomfort if not pain, that does not stop after the sandal is broken in.  Also almost all straps made in a commercial sandal are non-adjustable. If the straps are made of leather, the leather will stretch out and the sandal will fit poorly. Because of this, I resolved 50 years ago, and maintain this resolve today, to only make custom sandals. The major bones have to be marked on the foot tracing, which are the big ball, the little ball, and both inner and outer ankle bones. The straps need to encompass both balls in front, and be below both ankle bones in the back. That's for my design, which has nothing between the toes and is created so that the wearer can wear socks. I also resolved that every strap has to be 100% adjustable by the wearer, to either loosen or tighten each strap.  When I look at commercial sandals, I usually shudder at the thought of buying and wearing such a cheap, ill-fitting piece of junk. It's a little like being robbed, actually. I looked at the link you sent, to the Greek sandals. Sheesh, what a waste of effort to build those things! If there wasn't the Mediterranean Sea right there, and the sun shining, nobody would buy those things. And the prices! Wow. So high!

I won't change my design until I've worn this first pair and get some real feedback to my feet. While wearing them I'll make the second pair with thinner mid- and bottom-soles. Hopefully I'll find a microcell that will satisfy me. I'll try what I have on hand first, despite not knowing exactly what it is, except that it's pure gum rubber. I'll use the heels I have, too, just to see if they work. 

the cork is a good idea. I'll think about if I can incorporate it. I want my sandals to last a couple or three decades, and the cork might not be appropriate.

Edited January 29, 2024 by deboardp