Super sandals

Hacked sandals for running fast & long.

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Human shoes are an utter disaster for lions. After many Hokas & ASICs, the next step was sandals. They have since allowed personal record breaking speeds, but not as much distances.

Human shoes are an utter disaster for lions.  The single greatest idea for making human shoes fit lion paws came from

This is the only way we can run reasonable distances without blisters, pantar fasciitis, & black clawnails.  Over the years, as lion fitness improved, distances & speeds increased, & even this has run into limitations.  Barepaw running is unacceptable, because of the dog manure, human waste, & rocks.  Humans are nasty animals.

Another problem which has arisen is shoes are now being discontinued after only 1 production run.  Like books, programming languages & blockbuster movies, they're sold more for publicity & thrown away.  Finding another shoe which works as well as last year's blockbuster can take years, if ever.  The only long term solution is making shoes from scratch, from easily obtainable materials.

After extreme blistering in a 19 hour race, lions experimented with slow quarter miles in $8 Walmart sandals.  In the 19 hour race, shoes trapped sand & moisture from the beach track.  If they just had more ventilation, the problems might have been avoided. Sandals could actually hit decent speeds, with a bit more upswing.  It became clear the best chance lions have of reaching the next level is  modified sandals.  Sandals won't allow the maximum speeds, but they should allow the maximum distances.

Humans have since created

extremely expensive versions of $8 Walmart sandals, with more straps.  $40 for the Xeroshoes Genesis would be reasonable if it wasn't for another problem.  The last pair of shoes wore down in only 3 months.  Most of a lion's life is spent running on inner foam rather than rubber.  

The Goog may actually embargo all but adsense paying commercial links, since it reveals no hacks.  Of course, lions don't sew & don't want to be like the male humans who do sew.

A nugget of info escaped the Alphabet corporation's embargo.

Sandals & how to tie them.  All these guys have pretty beat up feet & watching their videos conjure up foot odors.  Something is a bit off when it's only being done by men.  The dominant search result is, but he's bald.  

1st lion run in sandals


Current bill of materials:

1mm Vibram soling sheet for the bottom, adhered with E6000:

For the top, 2x6mm white EVA layers tacked by E6000

or 10mm EVA combined with a 6mm EVA to get 16mm

Maybe a top layer of fake leather to improve traction in rain.

#18 yellow nylon mason line for the heel strap & toe strap.

White string is a different material that degrades over time, so yellow has been the only useful string.

E-6000 adhesive. 

Hot glue.

Cord fasteners with 8.25mm or bigger holes.

A polypropylene alcohol bottle turns into plastic reinforcement pieces.



The toe strap uses a bundle of 8 x #18   string, 19" long.

The heel strap uses a bundle of 10 x #18  string,...

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  • Luna update

    lion mclionhead11/10/2023 at 01:10 0 comments

    The Luna sandals which arrived in 2020

    went on to work quite well for walking but not running.  They have the grip required to climb hills.  The hot snotted fabric strap never had any problems as long as the hot snot was manetained & the laces were loosened before putting them on.  There were dreams of printing a more robust attachment or looping fabric through the existing holes.  There was a dream of sewing fabric on fabric instead of gluing. 

    The suede coverings needed washing after every outing.  They eventually shrank & didn't stick on so they were left off.  The bare rubber was acceptable for walking.

    The original link was lost to time, but lions believe they were the mono

    What was $80 in 2020 is now $110 so these will be the last lunas in the lion kingdom.  It's not clear what lions will use for walking when they wear out.  It might go back to shoes since walking was never subject to causing blisters.  $110 was once the domane of top tier Hokas.  The $140 Hokas are now $200 but inflation in a lion's mind doesn't equate to something getting less attainable, just the money being less valuable. 

    The replacement might be unpadded rubber since the only thing preventing the EVA sandals from being used for walking is compression. 

  • Pleather failure

    lion mclionhead06/25/2023 at 02:10 0 comments

    Many toenails were turning to the dark side when sitting directly on 16mm EVA soles.  Lubricant had a very negligible impact.  The mane suspects were the foam compressing & riding up the front of the toes & the stickiness of the foam.  The 12mm EVA soles were much easier on the toes.

    The big needs in an upper material were grip in rain & blister reduction. Bare EVA was falling short in these departments.

    The next step towards a better top material was spray adhering scrap fabric.  This was a total mess.  TSA gloves are definitely required.  The fabric didn't all look the same color, but it all adhered.  The lion kingdom's scissors are horrible at cutting fabric.

    Completed pair.  A better method is to glue an oversize piece & cut it later.  The gluing jig could use more improvement, maybe cutting bits of angle aluminum to precisely fit.  The big question was how the fabric would handle wear & water.

    Early testing had debonding around the edges in heat.  As for reducing blisters, fuggedaboudit.  Fabric might even worsen blisters.  It might be more tenacious than EVA & more like socks because it absorbs water like socks.  Paws felt a bit raw after a hot 7 miles on fabric.

    They might have reduced dry skin.  They might still do better in rain, but that's a few months away.  With the blister problem, fabric is still a total waste except for rain. 

    Elmers adhered where it wanted to & proved impossible to release without damaging the foam.  Hot water helped. 

    Suede might still be the ideal upper material, but the original 1/16" suede is now unobtanium. 

    There are heavy suedes for a price.  This piece is a 1/8" brick.


    The next material was fake leather.

    Fake leather was Elmered on.  It required some clamping.  Suspect more permanent adhesion is going to require full clamping.

    The big question was if the fuzzy side would adhere.

    Cutting oversized pieces after adhesion didn't go any better than cutting them before adhesion.  The scissors can't navigate around the laces.

    Some sections didn't adhere.  It was hoped enough would adhere to do some testing.  Fake leather had a new carpet smell lions haven't smelled in 30 years.

    After 8 miles on fake leather, it held on just enough but started to come off.  There was no obvious benefit over EVA.  It might have better grip in rain & might be less blister inducing because it dilutes the foam compression.  It didn't noticeably make the sandals heavier.

    The best solution might be a patch of hard material under the toes which doesn't compress.  Making the entire upper out of hard TPU might work, but would be expensive.

    The original reason for suede was to have a less grippy upper than rubber.  Hard TPU might be too abrasive.  There could be a hard TPU layer on top of EVA to even out the compression.  Fake leather could go on top of the TPU to provide grip in rain.

    Pleather was not removable without taking off foam.  A piece of cardboard went in under the toes with less tenacious school glue.  Cardboard is not much stiffer than foam & it has problems in water.  It actually yielded a noticeable improvement.  Harder materials in that thickness get expensive fast.  The long term solution is PLA impregnated with holes for adhesion.  Carbon fiber would be the most expensive.

    The thought has occurred of replacing the entire front chunk of 6mm EVA with a 6mm PLA section, but it would be expensive.


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  • Death of a toenail

    lion mclionhead04/29/2023 at 00:27 0 comments

    Another toenail goes to the toenail in the sky.  Not sure why the sandals eat toenails.  The general theory is bare EVA is very sticky & too much stickiness in the toe area causes blisters under the toenails.  You can't moisturize toes because moisturizer causes toes to stick.  Simultaneously, dry toes get cracked & swollen which also kills toenails.

    The leading idea nowadays is to lubricate the toe area but not use a moisturizer.  Another idea has been to cover the bare EVA with suede, but suede is heavy.  Suede has provided just enough stick but not too much & it's been immune to rain.

    The journey to a more tenacious sole has been long & slow, manely because every option is expensive. 

    Lions wonder if vibram rubber has ever been remelted & cast into other sole shapes.  The tooling might cost more than the rubber.  The case could be made for casting 1mm rubber soles with just the right amount of lugs.

    It turns out the 1mm vibram soles slide like glass on a freshly waxed mall floor.  They really are bad compared to shorter life rubber.  So ideas began to emerge of having a pair dedicated to less frequent trail use, with higher grip rubber.  Maybe a PLA positive could be used to create a moldmax negative & that could be used to form a grippy sole out of rubber.  There are very expensive rubber epoxies.  Balloon rubber is the grippiest rubber.  Natural rubber seems to be the key.

    There is 1.2mm sole rubber which calls itself anti slip.  15" x 11" is $10 bidie bucks.  What lions really want though are lugs.

    TPE has shown pretty good grip performance compared to TPU, but it's expensive.  The latest idea is printing a lugged 1mm sole out of TPE & hot gluing it to the sole of a retired sandal.  Maybe a pathfinder could be made of TPU to see if the lugs overcome the lack of friction.  It would have to be printed in 2 halves & welded together.

    The preferred lug design is just a regular pattern of square outlines.

    Hot glue rivets would go in the holes.

    In today's price of $60/500g it would be $6.

    A pointier lug might dig in more & reduce the price to $5.

    Then comes testing it.  The only place demonstrating the traction is near the very end of a long mountain climb.

  • New pair

    lion mclionhead03/22/2023 at 07:06 0 comments

    New pair of 16mm's after 9 months. Used the soldering iron to melt holes for the 1st time.  There is a plan  to make another pair just for testing sole materials.  They'll be hot glued.

  • 2022 edition

    lion mclionhead04/25/2022 at 22:31 0 comments

    They're lasting 800 miles.  The mane changes this year were reducing the rear lace to 10 passes of string & gluing the rear lace to the sole.  The most time consuming part is cutting all the materials.  Gluing 2 pairs takes 4 days because of the number of clamps.  

    The lifespan has been limited by large wear areas in the middle of the sole which would require a completely new sole.

  • Mountain test 1

    lion mclionhead03/27/2022 at 00:55 0 comments

    A long awaited test involved going up & down the mountain in 16mm sandals.

      The uphill segment was all done on trails.

    Only the last part of this section entailed using 4 paws.  The rest of this section was gnarly but doable in the uphill direction.

    Sadly, the sandals didn't have enough traction to attempt these 2 sections in the downhill direction.  The downhill direction was much gnarlier.  The laces weren't the problem, but the smooth soles weren't up to it.  There are no lugged 1mm soles.  Perhaps lugs can be glued on, but they're going to be heavy.  The great challenge continues to be steep sand covered clay.

    Steeper sections with exposed rock were doable.  Rock hits in the downhill direction were painful.  The downhills had to be slower than in shoes.

  • 16mm EVA #2

    lion mclionhead05/29/2021 at 19:55 0 comments

    The 16mm soles proved a decent compromise between speed & durability over 6 months. 

    Right paw compression was down to 6mm while the 12mm sandals compressed to maybe 1-2mm so the compression in both cases was 10-11mm.

    Left paw compression of the 16mm was down to 3mm, so the 12mm sandals may be a case of the foam compressing all the way down to a solid, with still more compression to go.

    Original 12mm compression.

     Despite having more cushioning, the soles still wore out fast.  They might have worn out faster because of the cushioning.  They might have gone 500 miles per pair.

    More proper clamping joined the next EVA sheets.  Because wood clamps are so nose bleed expensive & the pressures on foam aren't very high, there's motivation for 3D printing a jig for gluing the pieces.  Gluing sandals is just a very rare operation for such an investment in gear.  

    The 10mm foam was actually cuttable with ordinary scissors.  Making holes in the full 16mm requires an exacto.

    The 1st investment in cord locks in years.  The orange ones look a lot better, but only fit around the toe straps.

    Square plastic bits appeared to wear away the soles faster, so the they were rounded again.  Extra glue was applied to keep them oriented.

    The soles got a more aggressive clamping.  Another 10 clamps are still required to do it right.

    These are quite good.

    The clamping led to the best edges so far.  

    Black soling ran out with the shortages in 2021.  Extra patches will be glued to the worn areas as they wear out.

    The laces swell over time, making the cord locks tighter.  They're too loose when they're new.

    The last set underwent a lot of patching on the soles to worn areas.  They retained a lot more cushioning than 12mm.  They have a few more miles left before being discarded.

    Wear varied greatly, depending on the lacing variations & paw position.  Right paws are getting beaten up more than left paws.

    What's desperately needed are semi permanent adjustments for the rear & outside of the ankle strap.  They don't have to be adjustable in the field like the existing adjustment points.  Lions continue to dream of a 3D printed cord lock to fuse the 2 existing ones into 1.

  • 16mm EVA

    lion mclionhead12/06/2020 at 04:42 0 comments

    A combination of 10mm & 6mm sheets arrived, along with rounder plastic to try to reduce the wear.   The 10mm sheets can only be cut with an xacto.

    The last 12mm pairs compressed into paper.  Still looking for a denser foam.

  • Luna enhancements 3

    lion mclionhead08/06/2020 at 07:26 0 comments

    Back to the 2 triangle farsteners. A new theory emerged that larger ribbon loops might make the farstener areas more flexible. 2 loops can be enlarged, but a 3rd loop is too close to the pavement. It would have to be sewed instead of hot glued. Also, eliminating the cord locks & fixing the toe strap length might improve the toe strap. The lion paws have to heal from the last experiment before trying these on.

    Rubber cement has done a better job than hot glue at farstening the suede to rubber.  Suede continues to work well at avoiding blisters from the rubber.  Lions wash these after every run.

  • More luna enhancements

    lion mclionhead06/08/2020 at 04:15 0 comments

    The suede pieces from 2 years ago were taken off the xero sandals, after being untouched for 2 years. They looked absolutely ancient. It really was a long time ago when the sandal experiment began.  So much of that time was spent commuting, it felt a lot more recent.

    The suede ended any blistering from the rubber, but with increased running distance came another hot spot from the triangle farstener.  

    This was a total failure.  Hot gluing the straps makes them more abrasive.

    Another shift of the toe strap closer to the center.

    The cord locks from strapworks had strange, unused plastic bits which were ground off.  The lion kingdom suspects a smaller, more round shape is easier on the paws.  

    The toe strap made of 9 strands of white mason line was found to be too aggressively slicing lion paws, so it was popped out.  It held up surprisingly well, but to reduce the amount of pressure on the lion paws, it had to be thicker.

    A 2nd hole was drilled with a 5/16 bit.  It was found that the flexibility of the rubber prevented the hole from growing to the size of the bit.

    The traditional 2nd toe strap was put in.  This strap was made from 9 strands of #18 yellow mason line.  It fit through the holes just like the 9 strands of white mason line, despite fears that yellow mason line was thicker.  Maybe the original hole stretched from being worn.  This was 2 more strands than what the EVA sandals used for their toe strap.  The EVA sandals dropped to only 7 strands of yellow mason line, to allow it to fit through unmodified cord farsteners.

    It came out surprisingly well isolated from the pavement.  

    Another lace design taking out 1 of the plastic triangles went in.

    A slight twisting of the ribbon & protruding section ate lion flesh.  The new toe plug worked quite well, though.

    Ribbon laces have been quite a failure compared to string bundles, but there's no way to make a string bundle big enough to support such a heavy sole & fasten it. The sole has to be lighter or it needs a fabric upper. Lions have started leaning towards designing lighter soles that are better at buffering rocks, rather than trying to enhance the lunas.

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