Crossfire ( Aus ) P/L Combat Boot briefing
Crossfire ( Aus ) P/L Combat Boot briefing
Here is a letter recently sent to an OS military who requested a Combat Boot Briefing . I think it gives you an insight into the depth of experience behind our boot designs .
Crossfire ( Aus ) P/L PeaceKeeper Combat Boots .
The PK +(PeaceKeeper +) is a bit unique in that it was designed from the very beginning to be worn by the only occupational group we know of which actually runs , on any terrain , carrying half again their body weight .
The biomechanics of that task go far beyond the shock and stress ablation abilities of most footwear construction methods and materials .
Which is why we went back to first principals to build the family of Goodyear Welted boots .
Development History .
My previous firm , Wild Country P/L , was in the mountaineering and cross country ski trade in early 1980s .
We were importing boots from Europe . Beautifully made , but they hurt . It was almost accepted in those days that if you needed boots good enough to climb Mt. Aspiring you would be losing a few toenails.
Didn’t seem right to me , so I went to Europe and spent a lot of time in factories in France , Austria , Italy and Germany learning about last design and boot making .
Firstly I found that the low instep , narrow , rotated lasts were the fit problem . They were just the wrong shape for big wide , high instep ANZ feet .
So we invested in a full suite of lasts to our recipe . 27 years later we still use them .
Next I learned about the three main methods of boot construction .
- Welted . Goodyear or Norwegian .
A ribbed midsole board is the heart of the boot . Two main welted sewing lines engage the ribs and ‘ close the upper ‘ .
- Cemented .
Upper is made up over slip or curtain last . Bottom of it is buffed and glued to sole system .
- Injection moulded .
Molten rubber is injected into negative mould tool and cools onto upper .
The best of my visits was to an excellent firm in Germany. In 1984 I worked with them to make hiking and telemark boots of great quality . The Goodyear welt enabled us to include all the lining / Goretex / anti torsion shanks / shock absorbing foam etc needed to cope with the big stresses of skiing . And importantly it gave the midfoot flexibility for a long XC stride( this became vital for Combat Boot performance , more later ) .
The boot was a huge hit in the US and Australian markets . I still see some on the slopes .
However , like most European factories ours was looking at new technologies to reduce the use of highly trained craft workers and to speed up throughput . They went to unitised cement construction , and we learned a painful lesson . A platoon of Australian Defence mountaineers who experienced a batch failure of the sole glue at Annapurna . A very bad day in the field .
It became impossible to get the Goodyear Welted boots we wanted out of Europe so I got back on the road to investigate the US . After some years and a dozen factories of false starts we were delighted to find Dick Martens of Weinbrenner Shoe Co Wisconsin . The firm was a perfect fit with us . It is a century old and now employee owned . So the management has no interest in easing out highly trained workers , as they are the management . Consequently they have kept alive and thriving the Goodyear Welting skills , with capacity to do a half million or so pairs pa .
After the ADF climb of Everest in 1998 we shifted company work from Mountaineering to Military Gear .
In 2000 or so it was time for ADF to get new Combat Boots . Our early PK was in a trial of a dozen boots from worldwide, and did very well . However the tender was written only for injection moulding construction ( the Commonwealth had bought injection tooling already ) so our boot was excluded from consideration . For the next 20 years the issue boot has damaged feet , careers and combat capabilities . It has been defended by the system( see BRIG Nikolic interviews in the papers 2006 ) and hated by many troops ( thousands have told us so ).
Crossfire ( Aus ) P/L was placed in real bind .The system had no simple protocol for dealing with people who were hurt by the issue boot , or those who simply could not be fitted ( too big or two small ) . We became a defacto medical support Co . In the process we had acquired a good research cadre and priceless feedback .
So we made a non commercial decision to support the war effort by staying in production .
Some 1,000 people a year receive foot care help from Crossfire of a quality that the system cannot provide , but finally has formalised . People can now obtain medical approval to access non issue boots
When Afghanistan started the DMO reacted without thought and bought an inappropriate Mountaineering Boot with many problems . Which mean our workload of helping hurt individuals increased , as did our incentives to improve our boot and intensity of feedback .
20 years after the first models we now have a boot of a sound original concept , on a unique last , which has been continuously refined and includes materials developed specially for us .
Even better the Goodyear welt construction has made it easy to offer a family of boots , all built on the same last , with alternate materials for different tasks . Eg Navy boots , Flight boots , Cold weather , Jungle , Firefighter , Police etc .
The US Army has bought over 900,000 pairs of PK+ Steel Toe .
We wanted a boot to allow efficient ( and safe ) running , jumping , twisting , going to ground etc .
This required a last which promoted midfoot articulation for a ‘ strike and roll ” running gait . The boots underside is ‘ rockered ‘ like the foot wearing it . Not flat bottomed to ease popping out of injection tooling .
Note most work boots use a steel shank . Sole flex zone is just in front of the shank , well back from the midfoot . Promotes Plantar fasciitis , stresses the metatarsals and flattens arches .
PK+ has a doubled up synthetic athletic type shank which flexes progressively and in the right places . It allows big toe flexion for ‘ spring off ‘ . Each stride is longer but less energy demanding as the toe acts as a spring lever . In offhand stance the improvement in marksmanship is surprising . Better muzzle control when firing from the hip . Tendons and muscles from big toe to lower back can work as designed .
Ankle fore and aft flexibility is designed in by orientation of the fabric panels . Sideways and torsional stability is not compromised by this .
Shock Absorption .
In other construction techniques there is very little , or none , antishock material between foot sole and the road . In cemented types this is because of the difficulty of glue stabilising totally different materials to each other ( our Annapurna experience ) . In injected types it is because high quality foams would be melted by the process and thee is no room to fit them in .
Welting permits us to use the highest quality of preloaded foams which last the boots life without bottoming out .
Also , the space inside the welt rib is filled with cork compound which breaks in to the shape of the foot sole , dispersing load and eliminating ‘ hot spots ‘ .
Watch a soldier walking away from you . Nine times out of ten the boot heel will be breaking down sideways ( usually outwards ) , throwing out ankle / leg / spinal alignement . It is often an accelerating problem . As sole wears on one side the heel box breaks even more and injury becomes yet more likely .
PK+ Heel box is a water resistant styrene which is structurally sewn into the welt . No side collapse , no breakdown .
Once again , the simpler construction styles preclude use of the best quality linings .
Wet skin is more likely to blister . Skin comfort is determined by relative humidity at the surface . For foot comfort and health it is important to move water away from the skin as fast as possible . ” Walk Yourself Dry ” .
Flat non woven liners , low quality leather and coated nylon panels all slow breathing . PK+ uses a 3D free2air mesh to surround the foot surface with a moving layer of air to waft away humidity . Mesh is some 2.8mm thick which also gives over 5mm of size tolerance during break in .
We are ambivalent about waterproofing layers , using them in Alpine and Arctic boots . Sympatex , Goretex and eVENT are all good . In military use they can’t protect from water pouring off wet tussock and down the ankle , and actually slow down the drying process .
Liner socks made of stretch Lycra / Goretex are a very valid alternative . Sealed against the leg to resist water pouring from above , light , non blistering and super drying .
Decades of trials have taught us where the good materials come from . We are not constrained by the Berry Amendment .
Outsoles come mostly from Vibram . PK+ uses Sierra sole , Flight Boot -Matayur non FOD , Police boot -Polypillow etc .
Side Panels . We specify non coated Cordura for better breathability . We are experimenting with Nextec encapsulation .
Lacing . Tight woven laces to resist nasty corkscrew grass seed . Free running through quality hooks .
Pungi Plates . Anti-nail plates of ceramic / Kevlar . No extra weight , protection right out to the welt line .
Toe boxes . PK+ is crush resistant vacuum moulded nylon . Safety toes steel or composite .
Haven’t met a soldier we can’t fit yet .
Sizes 3 – 16 . Half sizes up to 12 .
Two widths standard ( 85% Australians go W ) .
Custom fits to order .
I suggest you might get value from trialling PK+ for Army wide use . With a pair of Stretch GoreTex for each soldier .
FireFighters – we suggest the PK Fire ( NFPA or Euro) .
Airforce – the PK Flight .
We do an exception to our Welt only rule . That is a very lightweight Barracks / Day wear boot with cemented sole . Really an 8″ khaki running shoe .
Many thanks for your interest . Much enjoyed the visit ,
Crossfire ( Aus ) P/L
138 Wallace St