Thread: My stropping technique.

The Glen hint to stropping:
Pay attention to the spine, really just make sure the spine is nice, flat, smooth, and even as it goes up and down the strop, everything else will do what it is supposed to.... that means use enough pressure to accomplish this too...

As to speed, at one time there was a test done about it, those guys found that extremely slow stropping did not do very well... That does not mean you should be speed timing yourself either 60-90 laps per minute hehehe
A nice comfortable "CONTROLLABLE" speed is more important..
And practice the flip, a butter-knife or very dull razor is good here, really I am not joking...

Originally Posted by gingahippy

I have just about stopped shaving with a straight because I can't get it quite sharp enough any more, for a while I could but now, it just pulls a little too much and I am sure it is my stropping.

I have been holding the razor with my thumb pad on teh bottom of the tang and index finger on the spine/back of the razor, so that appears to be my problem.

But if I try with my thumb on the spine of the tang then when i begin to strop away from me the razor is facing the wrong way and the only way I can see to flip it is the wrong way, ie it wants to flip underneath, against the strop. It doesn't seem possible to flip the other way. i can't watch any of the videos either since my connection is to slow and they all jump.

With the spine pointing away from you, the thumb should be on top of the tang, or the top corner closest to your body. The index finger underneath. Then push away, spine leading. Then on the trip back you rotate your thumb down and back, and your index finger rotates in the same direction, again spine leading.

I don't know if that description helps or hinders. I hope the former.

I can't beleive I have come this far to find I have been getting it so wrong.

What a suitable new smiley they have added to teh collection.

But now I have hope of getting over this hurdle, so close but sooooo far from actually being able to shave painlessly and quickly.

Hang in there. You'll get it, just be patient. If you can't strop you're way to a sharp edge, you may need to refresh it with some paste, finishing hone, or send it out.

Originally Posted by keenedge

With the spine pointing away from you, the thumb should be on top of the tang, or the top corner closest to your body. The index finger underneath. Then push away, spine leading. Then on the trip back you rotate your thumb down and back, and your index finger rotates in the same direction, again spine leading.

OK, I misspoke yesterday. "Then on the trip back you rotate your thumb down and back, " it should read, Then on the trip back you rotate your thumb *forward.* The index finger rotates in the same direction as the thumb is rotating, but it's heading back toward you.

Originally Posted by BKratchmer

There needs to be a certain amount of force to bend the steel. Since this cannot come from downward friction, a critical momentum needs to be met to really effectively strop. It's why you buff with rouge on a large, fast wheel- it will cut so slowly otherwise that it would take exponentially longer to get the same effect. No more pressure, just more speed.

There is NO physical support for this. Momentum=mass dot velocity (M=mdotV), or simplified, mass times speed (M=ms). Friction=normal times coefficient of friction (Fr=N(mu)). There is no reason to assume friction depends on speed. The friction on the blade edge is constant (assuming your downward (normal) force is constant)

If you were to supply an initial impulse there might be a critical momentum one would need to complete a stropping stroke, but since we are providing a constant force input, there is no "critical" momentum we need to achieve. This would be the same as accelerating a car to say 30 mph then letting it coast to a stop. In order to say, have that car travel 200m, one would need to have a critical momentum at the end of the acceleration. However, if you are going to supply a constant force (ie not coast) it would be a simple matter to travel 200m, you could have a momentum of 20kgm/s or 50 kgm/s it doesn't matter.

The reason you cut on a large, fast wheel is this. Distance = (pi)*d*w*t, or pi times diameter of the wheel times angular velocity times time. As such:
A 2" wheel, 2000rpm, 1 min= pi*d*w*t= 3*2*2000 = about 12000" a min.
A 4" wheel, 2000rpm, 1 min= pi*d*w*t= 3*4*2000 = about 24000" a min.
A 2" wheel, 4000rpm, 1 min= pi*d*w*t= 3*2*4000 = about 24000" a min.
Thus one can see, the bigger and faster a wheel, the more tangential distance is covered. The frictional force depends only on the normal force and coeffecient of friction, and the distance covered. Stropping faster allows you to cover more distance in a minute, but 60 laps in a minute or 60 laps in 5 mins should have the same effect.

Originally Posted by BKratchmer

See my post earlier in this thread...it's all about achieving a critical amount of force to bend the steel, and you need the force in a lateral plane. The slower you go, the more of the force has to come from a vertical plane.

This is complete BS I'm sorry. Take Physics 101 then come back and talk about it. Friction between solids depends ONLY on Normal (ie. vertical) force. Lateral force has nothing to do with it. Also, force is the derivative of momentum (ie. rate of change) so "establishing" a critical momentum doesn't even make sense. Momentum doesn't generate force. In fact, Newton's first law is "an object at rest stays at rest and an object in motion (has momentum) stays in motion, until acted upon by a force".

Originally Posted by gssixgun

The Glen hint to stropping:
Pay attention to the spine, really just make sure the spine is nice, flat, smooth, and even as it goes up and down the strop, everything else will do what it is supposed to.... that means use enough pressure to accomplish this too...

As to speed, at one time there was a test done about it, those guys found that extremely slow stropping did not do very well... That does not mean you should be speed timing yourself either 60-90 laps per minute hehehe
A nice comfortable "CONTROLLABLE" speed is more important..
And practice the flip, a butter-knife or very dull razor is good here, really I am not joking...

Last post I'm sorry. Glen is right, one does need SOME speed, but I'm pretty sure one could strop at 30 laps per min or 90 laps per min and you'd get pretty much the same result. As to technique, whatever works works, but I was taught to put the strop at a comfortable height so you can hold the handle around your midsection. Stand sort of sideways to it, and strop out and to the right. It's more ergonomic on your arm and shoulder to strop in a plane parallel*ish* with your shoulders, than out in front of you.

After reading the OP first post, my biggest concern, like VeeDub's would be stopping to razor at each pass, or at any pass for that matter. If it hasn't happened yet, rest assured you'll have an uncontrolled jerk of the hand in the wrong direction at some point instantly nicking your strop. Never let your razor come to a complete stop on your strop. I'm not a golfer, but I know they talk about the dreaded "yip" on the putting green where the golfer can have an involuntary tic or jerk. Stop the razor on the strop, have a yip and you've got a nick.

Chris L