Query
06-29-2010, 04:21 AM
Have any of you good spinners experimented with blade offsets to see how it affects your spin balance?
:bow:
Many of you have already have seen my theories of balancing skates by internal boot modifications, but to recap:
If blades are mounted completely wrong, you can't balance while skating on one foot without using more muscle on one side of the body than the other. You can always balance by changing your vertical alignment a little. But you may need a lot of muscles, in the foot or hip, to hold that position. For example, you may feel you need muscles to tilt your foot, because the two sides of the insole at the bottom of your boot don't press equally on the two sides of your foot, which in turn may take a lot of continuous asymmetric muscle use in your legs and hip.
Most boot fitters adjust the sideways blade position ("offset") so that you don't have to use more muscle on one side or the other. This is a minimal standard to which any decent fitter is held, or to which you should hold yourself if you mount your own blades.
The problem is, some people are still left with asymmetric weight support on the two sides of your foot, which still makes their foot sore. [Note this applies separately to each foot - offset is often different on each foot.] This was true for me.
You can also achieve the goal of balance without excessive muscle by changing the shape of the insole with tape, and/or internal boot shape modifications, as I discuss in my web page.
I ended up re-mounting my own blade (on each boot) so that it lies under the line between the center of my heel with a point midway between my big toe and the next toe over. Once the appropriate insole and boot modifications were made, my weight is most comfortably supported in that position, with approximately equal pressure on the bottom of both sides of the foot.
I think my spin balance was also slightly improved this way. But it is hard to be completely certain, because I'm not a very good spinner no matter what I do with the skates.
I believe that any really good boot fitter should do the same thing. Of course, small blade offsets of a couple mm doesn't affect weight support comfort much, so I see nothing wrong with that, but when fitters go beyond that, I think they are taking the easy way out, at the expense of making your feet and various connected body parts sore, and maybe affecting long term foot health.
:bow:
I've thought for a long time that blade mount offsets affect spin balance.
The physics are very complicated. To spin well, you balance the lower body asymmetry needed to skate on one foot, together with the sideways force from skating on an edge, with a strategically chosen upper body asymmetry and an overall orientation with respect to vertical.
Most skaters get it slightly off, in that they glide along a small circle as they spin, rather than staying exactly on one point. If the circle is small enough, everyone says it's OK.
But the size of the circle you can optimally achieve should be affected by the amount by which your blade mount is offset. In addition, it is sometimes desirable to make the upper body look as symmetrical as possible - e.g., the two hands and arms at the same height and at the same distance from the body.
But even if you do internal boot modifications, it isn't necessarily the case that the offset of optimally comfortable weight support will produce optimal spin balance, for a given human body.
So again, have any of you good spinners experimented with blade offsets to see how it affects your spin balance? What were the results?
:bow:
Many of you have already have seen my theories of balancing skates by internal boot modifications, but to recap:
If blades are mounted completely wrong, you can't balance while skating on one foot without using more muscle on one side of the body than the other. You can always balance by changing your vertical alignment a little. But you may need a lot of muscles, in the foot or hip, to hold that position. For example, you may feel you need muscles to tilt your foot, because the two sides of the insole at the bottom of your boot don't press equally on the two sides of your foot, which in turn may take a lot of continuous asymmetric muscle use in your legs and hip.
Most boot fitters adjust the sideways blade position ("offset") so that you don't have to use more muscle on one side or the other. This is a minimal standard to which any decent fitter is held, or to which you should hold yourself if you mount your own blades.
The problem is, some people are still left with asymmetric weight support on the two sides of your foot, which still makes their foot sore. [Note this applies separately to each foot - offset is often different on each foot.] This was true for me.
You can also achieve the goal of balance without excessive muscle by changing the shape of the insole with tape, and/or internal boot shape modifications, as I discuss in my web page.
I ended up re-mounting my own blade (on each boot) so that it lies under the line between the center of my heel with a point midway between my big toe and the next toe over. Once the appropriate insole and boot modifications were made, my weight is most comfortably supported in that position, with approximately equal pressure on the bottom of both sides of the foot.
I think my spin balance was also slightly improved this way. But it is hard to be completely certain, because I'm not a very good spinner no matter what I do with the skates.
I believe that any really good boot fitter should do the same thing. Of course, small blade offsets of a couple mm doesn't affect weight support comfort much, so I see nothing wrong with that, but when fitters go beyond that, I think they are taking the easy way out, at the expense of making your feet and various connected body parts sore, and maybe affecting long term foot health.
:bow:
I've thought for a long time that blade mount offsets affect spin balance.
The physics are very complicated. To spin well, you balance the lower body asymmetry needed to skate on one foot, together with the sideways force from skating on an edge, with a strategically chosen upper body asymmetry and an overall orientation with respect to vertical.
Most skaters get it slightly off, in that they glide along a small circle as they spin, rather than staying exactly on one point. If the circle is small enough, everyone says it's OK.
But the size of the circle you can optimally achieve should be affected by the amount by which your blade mount is offset. In addition, it is sometimes desirable to make the upper body look as symmetrical as possible - e.g., the two hands and arms at the same height and at the same distance from the body.
But even if you do internal boot modifications, it isn't necessarily the case that the offset of optimally comfortable weight support will produce optimal spin balance, for a given human body.
So again, have any of you good spinners experimented with blade offsets to see how it affects your spin balance? What were the results?