(Crossposted from SwordPeople.)

I almost exclusively wear SoftStar Shoes these days, typically RunAmoc Dashes of various description. They’re my walking shoes, my hiking shoes, and my fencing shoes. And I do a lot of these things, so they wear out pretty quickly. At over $150 shipped, I can’t really afford to order a new pair of SoftStars every time I wear through a pair.

For me, Dashes tend to wear out in the sole long before the uppers start quitting. I had previously sought out local cobblers to get them resoled, but the most recent time I took them to a shoe repair place, they charged me $75 and took 2 months to basically superglue a piece of 6mm rubber onto the existing, worn-through 5mm rubber. Not only did this make the shoes very inflexible, it also meant, due to how the original soles had worn, that the footbeds were no longer flat (or “zero drop” in minimalist shoe lingo), which kind of defeated the purpose of wearing minimalist shoes in the first place.

So after that, I decided to start resoling my shoes myself. The results aren’t as professional as a good cobbler, not by a long shot, but for a modest investment in supplies I can resole a pair of SoftStars for about $10 in materials and an hour of my time, and retain all of the original flexibility and profile of the shoe. That’s definitely time and money well-spent in my book, especially compared to my most recent experience with the local place.

In my experience, I can get one to two resoles out of a pair of Dashes before the uppers get too compromised to be useful. You can make the uppers last longer by ordering them with the non-perforated leather, by wearing socks with your shoes, by unlacing the shoes before you remove them, etc. When my shoes do fail, the leather at the heel is usually the first thing to go, splitting in a way that makes a stitched repair difficult. (I have never had a chance to resole SoftStar Ballerines, since their leather always seems to fail before the soles wear out. I suspect this is because the Ballerines’ sole profile is relatively smaller than the Dash, and so the seams around the midsole end up abrading against the ground more, causing the leather to fail.)

Anyway, enough with the recipe blog post introductory BS. Let’s get to it.

YOU WILL NEED:

A pair of SoftStars or similar shoe, in need of new soles, with the shoe body in decent shape.

Kids’ shoes optional. (They also needed a bit of fixin’, so.)

Several other items, including…

• A sheet of rubber soling material, sometimes called “rubber crepe”.
  • This comes in standard sizes and varying thicknesses; a 38cm x 28cm sheet costs about $10 and is enough for one pair of men’s US size 12 shoes with wiggle room to spare. Pictured are this item from AliExpress, which is what I usually use, along with this product from Amazon at a similar overall price (this is a bigger sheet, enough for at least 2 pairs). Today I’ll use the Amazon stuff to mix things up a bit.
  • I like a thickness of about 2mm. If you’re looking for a closer match to a new shoe, the standard material that SoftStar now uses on their Dash line is a 5mm Vibram product — real Vibram shoe rubber is considerably more expensive than what I use. (Ballerines use 4mm Vibram Cherry.)
  • You could also use bullhide if you wanted to replace leather soles. I have yet to find a supplier of leather that looks like a good match to what SoftStar uses, and given leather prices I’m not in a hurry to experiment. SoftStar uses an 8-10oz (3-4mm) bullhide leather.
• Contact cement.
  • I use Renia Colle de Cologne, which is a toluene-free contact cement similar to the variety that SoftStar uses in their workshop. A liter of it costs about $35 and is available from leather suppliers and the like. This is way cheaper than the neoprene cement at the hardware store and will also give you less cancer. 
  • If you’re gluing leather soles onto a leather midsole, you can also use nontoxic, water-based adhesive.
• A small brush that you don’t mind getting covered in contact cement.
• A rubber mallet.
• A rasp or some rough sandpaper, for roughing the surface of the sole and the rubber prior to bonding.
  • I’m using this little rasp I got on AliExpress for like $5. It’s basically a scroll saw blade that’s been wrapped carefully around a stick. Also some 60-grit sandpaper.
• Some scissors or a utility knife, for cutting the rubber sheet.
• A permanent marker or tailor’s chalk to mark the rubber sheet for cutting. I’m using a silver Sharpie for easy photographing, but a black Sharpie is actually decently visible on the rubber’s surface.

POTENTIALLY HELPFUL:

• Thinner for your contact cement.
  • When I ordered my Colle de Cologne I also ordered a liter of Renia’s compatible thinner, since I knew it would take me quite a while to get through the liter and I didn’t want it to go bad. The thinner is also helpful for rejuvenating your glue brush after it dries out.
  • I would not recommend thinning your contact cement unless it’s unmanageably thick. If the cement is too thin it’ll affect its adhesion properties.
• A pair of pliers, to assist with removing recalcitrant soles.
• A belt sander, if the soles have left remnants after removal.
  • This has never been a significant issue with the original SoftStar soles, but I’ve had the issue with the soles that the shoe repair shop did such a poor job of.
• A glue pot.
• Heavy duty polyester thread or artificial sinew, a sewing awl, etc., if you plan to do any repairs.
  • For a turned shoe like a Dash, resoling is an ideal time to fix a popped stitch since you can only turn the shoe with the sole removed.
• A toy bulldozer, I guess?

STEP 1: Remove old soles

The first thing you need to do is yank off the old soles. The easiest way to do this is usually from the toe or the heel, and indeed you might already have some delamination occurring at one of these areas that can facilitate this. Just grab the shoe in one hand and the rubber in the other and yank. Try to avoid putting a lot of stress on the stitching, or on the leather uppers, especially if they are the thin perforated leather — once the sole starts separating just make sure that your “shoe” hand is gripping the midsole rather than the upper itself. Go slowly and try to keep your grip as close to the glue seam as possible, at least during the first half of the process.

If you need help, you can grab the rubber with some pliers (welding pliers might be useful here, but almost anything will do) or even a bench vise. Just make sure your grip is close to the adhesion, and try to move your grabbing point across the width of the rubber to avoid stressing it too much — the sole removal process goes smoothest if you can get the rubber off in one piece. I find that (picture notwithstanding) holding the pliers perpendicular to the shoe, near the glue seam, and rolling the rubber onto the plier jaws, works really well. (Note that in the photo above I am not holding the shoe body with my other hand, since it was busy with the camera.)

In this case, I have these giant honking frankensoles glued to the shoes (from the experience with the terrible cobbler), and the rigidity of the soles makes the process more difficult. I had the same problem with another pair of shoes I took to the same cobbler at the same time, and once I freed up enough of the soles I finally gave up and just stepped on the rubber and essentially deadlifted the shoe bodies off of the soles. I ended up doing the same here once I got the process going with the pliers.

You might find some rubber remnants left on the soles, depending on how well the removal process went. 

Use a utility knife, a belt sander, or some sandpaper to remove it. I pulled off most of the extra rubber with the pliers, then scraped and sanded by hand. I was satisfied with both shoes at this point:

 STEP 1.5: Do you want to do any repairs?

Once you’ve got the soles off, now is your chance to do major repairs. If you have a split seam, you can turn the shoe inside out (carefully!) and properly mend the seam.

Remove the laces from the shoe, push the tip of the toe into itself, reach inside the shoe and start pulling the toe through. Try not to stress the seams too much.

I probably should have reinforced the seams on the shoes before proceeding but I was feeling lazy today. There is a small repair I know I’ll need to make on this pair but it’s on the upper leather itself so it doesn’t require turning. I’ll take care of it later.

STEP 2: Trace and cut

If you haven’t already unlaced your shoes, do that now. Don’t lose the laces!

Take your rubber sheet and place it grippy-side down on a flat surface. Depending on your shoe size and the size of your rubber sheet, you may be able to “tetris” more than one pair of shoes’ worth of soles out of the sheet. Place your two shoes on the sheet with a bit of space between them and think about how you might arrange additional shoes on the sheet, or leave as much useful rubber available in one piece for another purpose. Don’t be too stingy, though, since you’ll want to leave a generous margin around each shoe for cutting out the sole blanks — this will make the gluing process much less fraught. Leave about 1 to 1.5 centimeters clearance on all sides of each shoe.

Also, if you have a rubber sheet like this one, where the grip pattern has a clear “grain”, you’ll want to ensure that you’re placing the shoes so that the grip pattern is in the right direction.

Once you have a sense of how to place the shoes, take them one at a time and trace their profile on the back of the rubber sheet with a permanent marker. I like to grab the leather of the uppers and bunch it up as I do this, to be able to trace the profile of the shoe as accurately as possible. Nevertheless, I try not to be too fussed about getting the marker line too close to the shoe itself. We want a bit of margin anyway, and I also don’t want to get permanent marker all over my shoes (this is something I failed at today).

Repeat for the other shoe. Make sure that the shoes have adequate margin between them. These ended up a bit closer than I would have liked, to be honest, but it turned out all right.

Once the shoes are traced, cut out the profile from the rubber sheet using the scissors. I tend to cut outside the lines I traced by a good half-centimeter at least, to add even more margin.

STEP 3: Scuff and brush

Once the soles are cut out, it’s time to get ready for gluing!

Contact adhesive works through a mechanical-chemical process. Each surface is coated in adhesive, then the two surfaces are brought together and stressed. The stress causes crystallization to occur in the adhesive, fusing the two layers and creating a strong, permanent bond. However, the adhesive still requires a good mechanical bond with the substrate. To ensure this, we need to roughen up the surfaces that will be taking the glue.

To create a good surface for the adhesive to bond to, we’ll thoroughly scuff the back of the rubber sheets. This material is shinier than the stuff I usually use, which also means it’s slicker. So you’ll need to diligently scuff the whole surface. I used a combination of my little scuffer and some sandpaper, until the shine was thoroughly removed from the rubber.

Compare the left (scuffed) sole rubber to the right (shiny) above. I’m about satisfied with the scuff level here. (I then repeated the process for the other sole.)

Even though the leather midsoles are already pretty rough, I also scuffed them up a bit. For one thing this helps to break through the old adhesive layer and any rubber I wasn’t able to remove and ensure that the new adhesive soaks into the leather a bit.

When scuffing and applying adhesive to the midsole, I’d recommend holding the shoe in the “pinched back” position that I used for tracing. You want to avoid scratching up (and over-gluing) the uppers, just giving attention to the midsoles:

Once all the surfaces of both the shoe rubber and the midsoles are adequately scuffed, I painted each surface with contact cement. 

Using the brush, cover the rubber sheet with an even coating of cement. The adhesive will have a natural thickness that it “wants” to be painted on, that will be neither gloppy nor streaky. Get a nice, consistent covering across the whole sole with no wet lumps and no bare patches. Once that’s dried for a moment, do another pass around the edges of the rubber blank, concentrating on the heel and the toe. Repeat for the second rubber sheet.

Now repeat the process for the midsoles of the shoes. The leather is likely to be a little thirstier than the rubber. As before, try to find the level of coverage that is natural for the glue, then do another pass around the edges, heel, and toe. Get as close to the edge of the midsole as you can without getting glue onto the upper.

Carefully set everything aside to dry. Don’t let any glued surfaces touch, or they will not come apart without significant frustration and ruined work. Make sure you set your work out in a way where you won’t forget what pairs with what.

Every contact adhesive has a minimum and a maximum drying time. Usually the minimum is something like 5-10 minutes and the maximum may be as little as an hour or as long as a full day. For this cement, a wait of 10 or 15 minutes should do it.  Don’t be impatient, though! It won’t bond right if the adhesive is still wet when you mate the parts. (To kill the time here, I worked on the kid’s shoes that needed fixing.)

STEP 4: Stick, trim, and smash

Now comes the actual gluing. Important note: you only get to do this once. So take care.

For each shoe, we are going to mate the shoe body to its sole. Place the sole (glue side up!) on a flat surface. Pick up the shoe, and (glue side down!) carefully align it in midair above the sole. Hold it so that the midsole is as flat as possible, without wrinkles, puckers, or other weirdness that might lead to a bad bond, an uncomfortable final product, or a bad position for the sole. Try to get the upper out of your way as much as possible. You’re now ready to mate the shoe to the sole.

Carefully place the shoe directly on the sole, working either from the middle out or from one edge to the other. Follow through until the shoe and sole are fully mated. Once the shoe and the sole touch, there’s no going back, so make sure you’ve got a good angle! Keeping the upper out of the way as much as possible, take your hand and press the sole and shoe together all around, focusing on the edges.

Ideally, you now have a shoe with a new sole, with the midsole cleanly and flatly mated to the shoe rubber. There should be a centimeter or so of extra rubber extending past the edges of the shoe. We left all this margin so that if you screw up your initial contact, there’s a better chance that the whole midsole is covered with rubber. Good thing, too, because I came REAL close to a bad placement on one of the shoes:

Now take each shoe and trim the excess rubber from the sole. I try to get within a couple millimeters of the midsole as I’m trimming all the way around, though since I use scissors I’m less particular about the arch area, since the curve makes it hard to follow the profile with the scissors. Other than that spot, you want neither too much rubber (which can lead to snags, trips, delamination, etc.) nor too little (which can cause the midsole or seam to be exposed to excessive wear and prematurely cause the shoe to fail).

Once the shoes are trimmed, it’s hammer time. Take your mallet and, with the shoe on a flat, firm surface, hammer it all over. The hammer striking the shoe and transferring energy to the adhesive layer is what triggers the crystallization of the glue and creates a durable bond. You want to give a lot of firm hammering on the entire surface where the shoe and rubber are mated. Give extra focus to the heel and toe. Don’t worry too much about mushing up the heel counter; it seems to be capable of taking the abuse. 

Do try to keep the lacing eyelets out of the way while you hammer, so they don’t get smooshed and don’t damage the leather.

Congratulations, you just resoled your shoes!

STEP 5: Re-lace and enjoy!

Lace your shoes back up however you like. Your shoes are immediately ready to wear!