jack-mac wrote:
They do both, "It depends".

On the off chance you've ever examined the grooves sometimes worn in shoes on the solar heel surface, was the wear from lateral to medial, or medial to lateral? I hope your not basing your theory on the wear on the underside of the shoe at the heels , because I'm afraid you are being mislead by it LMAO I bet you see it more on an aluminium plate then a steel shoe & it looks like the heels of the hoof must be flexing inwards not expanding out wards due to the appearance of the ware, the misleading ware is from the downward force & the shoe springing out words first , the longer you fit the heels of the shoe the more it will ware added by the shoe moving forwards with growth , if you think I'm wrong tack a bar shoe on , see if you get the same ware positioning ,you wont. when the heels hit the ground the short pastern bone starts to sink in to the capsule straight afterwards, the heels expand.

jack-mac in gray, my old stuff in brown, stuff deleted

On the off chance you've ever examined the grooves sometimes worn in shoes on the solar heel surface, was the wear from lateral to medial, or medial to lateral?

I hope your not basing your theory on the wear on the underside of the shoe at the heels , because I'm afraid you are being mislead by it LMAO

My goodness! It appears I have the choice of being "misled" by my lying eyes and Pascal's Law or believing your illogical "lateral expansion" nonsense, which is apparently based on your profound ignorance of both anatomy and the behavior of liquids under pressure in elastic containment.

I can pick a winner.

I bet you see it more on an aluminium plate then a steel shoe & it looks like the heels of the hoof must be flexing inwards not expanding out wards due to the appearance of the ware, the misleading ware is from the downward force & the shoe springing out words first ,

"Shoe springing out?" It doesn't happen! Neither Fe nor Al shoes flex appreciably in the solar plane; i.e., across the web. Carry on Jac, you're getting funnier with each attempt to deny reality.

cuttinshoer wrote:
to back up that; do you have reasoning for that?

Juhani Takanen wrote:
“Because of the natural physiology of the hoof capsule, we have to take into consideration the tolerance margins of expansion, contraction, compression and distortion. It is well documented that as the hoof capsule comes under weight loading it changes its configuration by contraction of the heels, expansion of the quarters and compression at the toe. We further have to consider the element of shearing forces as the horse turns and maneuvers its body mass over the foundation of the foot. " (Duckett)

"Frog pressure is not required for hoof expansion, and in some hoofs, increasing frog pressure without changing the hoof angle caused contraction, instead of expansion. "(Colles)

"According to Dollar, earlier experimenters Lechner, Gierth, and Dominik each measured contraction at the heels occurring naturally under weight bearing. Though a larger number, including Lungwitz, claimed to find expansion of the heels, Dollar, apparently unable to prove or disprove the conflicting reports, settled for the consensus, with some additional weight given to experiments with live hooves -- of which, Lungwitz did the greatest number."(Heymering)

"According to Dollar, Lungwitz' measurements of normal hoof motion were dependent upon "Flexibility of the horn, and a well developed but untrimmed frog." (Heymering)

"According to Reeks, in the absence of frog pressure Lungwitz found, "Contraction of the solar edge of the heels occurs at the moment of greatest over-extension of the fetlock joint -- that is, in a foot with pressure from below absent. On the face of it, this appears impossible. Lungwitz, however, has perfectly demonstrated it ... "is but a simple and natural result of foot dynamics. The movement of the plantar cushion will now be downwards, as well as backwards, and, seeing that it is attached to the inner aspect of each lateral cartilage, we shall expect these latter, by the downward movement of the plantar cushion, to be drawn inwards. This Lungwitz has shown to occur."(Heymering)


Logically, a plastic structure such as the frog, bordered on either side by the empty space of the lateral sulci would function so as to do everything but bear weight, or transmit pressure laterally.(Heymering)

"Consider what would result if the internal mechanisms of the hoof functioned to produce expansion. Because of its slope, the hoof wall by itself would expand during weight bearing -- the more weight and the more often it bore weight the more it would expand. If the internal structure increased that effect then one should expect to see collapsed or exploded hoofs from running or jumping. Clearly, the hoof must function to retain its integrity by counteracting external forces, not amplifying them. The action of the hoof with little or no frog pressure as described by Lungwitz should do just that -- internally producing contracting force simultaneously and in direct proportion to the external forces of expansion, or possibly slightly greater than the external forces of expansion, as that would result in a slightly more upright wall in the quarters, better able to withstand the load."(Heymering)

"Hunting (1941) largely accepted Lungwitz's conclusions but kept some reservations: '"the heels and quarters may be pressed together to some extent but they are prevented from being forced asunder by the fibrous connections of the frog-pad (plantar cushion) . . . expansion . . . may be practically disregarded in considering the best methods of shoeing sound feet." (Heymering)




There is more if needed.

Tom Stovall, CJF wrote:The only one absent to reality seems to be you tom , you haven't had a lot to do with any brake pressing of cold metals nor deflection & creping back of metals & there molecule structure after pressure is applied or hydraulics for that matter ,lets take the example of you not knowing much about an aluminium race plate & its manufacture first , it has a hardened metal insert in the toe region one to help stop the toe from ware & also to help prevent the shoe from spreading excessively under pressure if you wish to dispute this I suggest you contact the manufactures & tell them its not needed & there wasting there thousands of dollars putting one in every plate. I think the physics of trial & error supports the necessity of the metal insert

Know lets talk about hydraulics, circulation & the hoof capsule , the physics of which seems to of eluded tom , first off you have to have a check valve, to control flow - direction , intake & back flow as in the hoofs case , it is not in a stagnant hydraulic state as one would find in a car hydraulic shock absorber, the hoof capsule needs to be regularly replenished with enriched blood or cell structure will die just like any other cell structure staved of enriched blood,if we except Toms hypothesise, the lest resistance would be back up the artery from which the blood flow came every time pressures was applied to the capsule, resulting in a dangerous back flow, better know in med terms as shunting were co2 levels & other toxins build up from lack of circulation & filtration from the kidneys & lungs causing massive tissue damage & death to tissue,not to mention excess exertion on the heart to supply the lower limbs with blood , now before I go on any further why the heels expand out wards & not inwards , Tom might be able to explain his hydraulic theory's a little better on the model he has presented other then quoting Pascal's Law

cuttinshoer wrote:please post it , its lovely nonsense ,are there any photos of Heymerings shoeing examples ?

While I'm waiting for Tom , ill list a few things to ponder over, a concave sole with the weight of the horses bone structured place upon it at full force , should (A) Flatten slightly or ( concave upwards more ,the collateral sulcus & bars are of an angling to best suite (A) inward contraction of the heels when load is applied Or ( out ward expansion when load is applied , (A) a narrow cleft frog & contracted heels are stronger, better for support & make for a sounder horse then ( a horse with a wide cleft frog & non contracted heels , (A) liquid mass implodes under contained hydraulic pressure , OR ( liquid mass dose not implode under contained hydraulic pressure.

Still waiting Tom ,OH & last I heard when blacksmithing welding & boiler making , steel does expand & contract, to what extent is due to its molecule property's , temperature, tension & stresses placed upon it. pressure is a funny thing when it comes to ware on differing materials, bit like how the heels of a metal shoe will ware yet the horn of the foot wont , the horn being less harder ,might have something to do with frequency

jack-mac in gray

The only one absent to reality seems to be you tom , you haven't had a lot to do with any brake pressing of cold metals nor deflection & creping back of metals & there molecule structure after pressure is applied or hydraulics for that matter ,lets take the example of you not knowing much about an aluminium race plate & its manufacture first , it has a hardened metal insert in the toe region one to help stop the toe from ware & also to help prevent the shoe from spreading excessively under pressure if you wish to dispute this I suggest you contact the manufactures & tell them its not needed & there wasting there thousands of dollars putting one in every plate. I think the physics of trial & error supports the necessity of the metal insert

Do you really believe the primary purpose of the Fe wear plates in Al race plates is not to reduce wear or increase traction, it's to keep the heels in the solar plane of the shoe (across the web) from spreading excessively under load?

Who knew?

In reality, your specious argument does not explain the rather inconvenient fact that one sometimes finds lateral to medial grooves on the solar surface of the heels of Fe shoes, grooves that could only be formed by the heel's movement being lateral to medial.

Try again, Jac.

Tom Stovall, CJF wrote:Oh I forgot your part of the toe dumping crew horses don't use there toe to get lift & propulsion , sorry for me to think you might realise shoe's can & do spread & contract under pressure , but then you have never made a race plate have you Tom, aluminium or spring steel, we made them out of light section spring steel for the reason stated before aluminium .but you would know that if you were the great race plater you claim to be know explain your hydraulics "Implosion" that's not Pascals Law so your contradicting your heel claims with the physics you put forwards.

jack-mac wrote:
You pay close attention don't you. Heymering was doing research on others findings comparetively.

See the harden metal insert, its not a toe grab ,toe grabs are band over here & in NZL still want to tell me shoes don't expand & contract under pressure when the toe digs in to the ground

cuttinshoer wrote:Maybe if he studied more in physics physiology & anatomy he might of not wasted his time on publishing. I do play close attention I just felt it didn't merit much of it .