Ok, I said I would post a simple and inexpensive way to measure base bevel angles. I will discuss side bevel angles measurement too. There are several tools out there that do the job well, but are in the $300 dollar range, roughly. If you have a true bar, or straight edge, you can do it for minimal additional $$. What you need:
1. Magnifying glass (depending on how your up close vision is, if over 50 you need something like these)
2. Feeler gauge that has a .010, .020, .030, .040 inch tab, or a mm one for .25, .5, .75, 1.0, 1.5
3. A good backlight
Here is my set up that I spent much less than $100 on it, including the straight edge.
Here are some graphics on what a base bevel is, for those not familiar with the term
Some info on the math (Trig) behind the measurement (copied from SKIMD)
OK, so onto how to do it yourself. Here are my pic's of me measuring a base bevel of around 0.75 deg. Put your true bar on the base, perpendicular to the edges. Put the light behind the true bar facing the true bar and look at the strip of light coming through the gap between the Ptex and the bar. Make sure your base is reasonably flat (the light is even height and if you try to rock the bar side to side does the light change? If you can rock the true bar, your base is not flat and your measurement will be in-accurate a little. Also if your base is convex, there will be a smiley shape to the light. You are edge high then.
Notice the circle and the light coming through between the edge and true bar. That is your base bevel. If no light is coming through, you have a 0.0 degree base bevel.
to measure it, make a mark on your true bar 60mm from the end. put the mark over the outside edge of your ski edge as shown below. Then rotate the true bar until the light between the true bar and edge closes off. That gap at the end of the true bar between your base and the bar is your bevel angle. Per the pictures above: 1mm (.040") gap = 1.0 deg; 0.75mm (0.030") = 0.75 deg; 0.5 mm (.020") = 0.5 deg, etc.....
I have rotated the true bar and closed off the light, time to measure the gap by sliding feel gauges under the tip of the bar. I am a little off with my 60mm mark, I only have 2 hands and should correct this before using the feeler gauge.
This gauge is not the right measurement, since there is still light coming through the gap.(gauge too thin)
this gauge is the right one since the light is shut off. If the gauge is too thick, you will see light on the inside edge.
Now, slide the set up down the ski and take another measurement. You can do as many or little as you want. It is a "specific spot" measurement. Ideally, they should all measure the same gap. When I get a ski back from SKIMD, they do. I have never measured a new ski from the factory with a constant bevel along the entire length of the ski. Some vary just a little (.25 deg) some a lot (2.0 deg). The bevel should be 1.0-0.5 deg and constant, otherwise you will notice the ski acting poorly on hard snow. Soft snow you won't feel it.
And lastly, flip the ski around and measure the other edge. And then do the other ski. Just some advice, I start at the tip, and make about 4 measurements along the length of the ski, then flip it around and do the other edge. I get 8 measurements per ski. That seems like plenty to me. Its up to you how many to make.
that all there is too it. You can check your skis after they come back from a tune and see if the shop actually put the bevel on you requested. I would estimate the accuracy of this measurement to be within 0.25 deg. If you ask for 0.5 and measure 0.75 that can be measurement error, but if you measure 1.0 or greater, its the shop.
For side bevel angles, I use my side edge sharpening tools and just match up angles visually. This will get you within 1.0 deg of what it is. I just set my tool to say 3 deg, hold it up to the side edge, then try 4 deg, and then try 2 deg. You can see what is the closest. Since you don't have a flat base to measure a gap, you can't do the base bevel approach.
1. Magnifying glass (depending on how your up close vision is, if over 50 you need something like these)
2. Feeler gauge that has a .010, .020, .030, .040 inch tab, or a mm one for .25, .5, .75, 1.0, 1.5
3. A good backlight
Here is my set up that I spent much less than $100 on it, including the straight edge.
Here are some graphics on what a base bevel is, for those not familiar with the term
Some info on the math (Trig) behind the measurement (copied from SKIMD)
OK, so onto how to do it yourself. Here are my pic's of me measuring a base bevel of around 0.75 deg. Put your true bar on the base, perpendicular to the edges. Put the light behind the true bar facing the true bar and look at the strip of light coming through the gap between the Ptex and the bar. Make sure your base is reasonably flat (the light is even height and if you try to rock the bar side to side does the light change? If you can rock the true bar, your base is not flat and your measurement will be in-accurate a little. Also if your base is convex, there will be a smiley shape to the light. You are edge high then.
Notice the circle and the light coming through between the edge and true bar. That is your base bevel. If no light is coming through, you have a 0.0 degree base bevel.
to measure it, make a mark on your true bar 60mm from the end. put the mark over the outside edge of your ski edge as shown below. Then rotate the true bar until the light between the true bar and edge closes off. That gap at the end of the true bar between your base and the bar is your bevel angle. Per the pictures above: 1mm (.040") gap = 1.0 deg; 0.75mm (0.030") = 0.75 deg; 0.5 mm (.020") = 0.5 deg, etc.....
I have rotated the true bar and closed off the light, time to measure the gap by sliding feel gauges under the tip of the bar. I am a little off with my 60mm mark, I only have 2 hands and should correct this before using the feeler gauge.
This gauge is not the right measurement, since there is still light coming through the gap.(gauge too thin)
this gauge is the right one since the light is shut off. If the gauge is too thick, you will see light on the inside edge.
Now, slide the set up down the ski and take another measurement. You can do as many or little as you want. It is a "specific spot" measurement. Ideally, they should all measure the same gap. When I get a ski back from SKIMD, they do. I have never measured a new ski from the factory with a constant bevel along the entire length of the ski. Some vary just a little (.25 deg) some a lot (2.0 deg). The bevel should be 1.0-0.5 deg and constant, otherwise you will notice the ski acting poorly on hard snow. Soft snow you won't feel it.
And lastly, flip the ski around and measure the other edge. And then do the other ski. Just some advice, I start at the tip, and make about 4 measurements along the length of the ski, then flip it around and do the other edge. I get 8 measurements per ski. That seems like plenty to me. Its up to you how many to make.
that all there is too it. You can check your skis after they come back from a tune and see if the shop actually put the bevel on you requested. I would estimate the accuracy of this measurement to be within 0.25 deg. If you ask for 0.5 and measure 0.75 that can be measurement error, but if you measure 1.0 or greater, its the shop.
For side bevel angles, I use my side edge sharpening tools and just match up angles visually. This will get you within 1.0 deg of what it is. I just set my tool to say 3 deg, hold it up to the side edge, then try 4 deg, and then try 2 deg. You can see what is the closest. Since you don't have a flat base to measure a gap, you can't do the base bevel approach.
