All you need is a couple of coins, a 12" ruler, a flat surface, two pencils, and to know what to look for. These 4 easy tests can give you a good idea of how well your blades were mounted and the condition of your blades after sharpening.
TEST #1: ARE YOUR BLADES STRAIGHT?
To determine if the blade was mounted straight hold up a straight edge, like a ruler, to the blade length. The blade should contact the straight edge all the way along the side of a parallel blade, such as a Pattern 99. Do this on both sides of the blade since the error is more obvious when the blade curves away from the ruler. When testing tapered blades, such as Phantom or Gold Seal, or parabolic blades the gap between the blade and the straight edge should be the same on both sides.
A good indicator of properly mounted blades are the screws. If the screws are mounted squarely it puts equal pressure on the blade plate holding it secure. If they are on an angle it will pull the blade plate to one side or another and increase the chances of the screw head breaking off. To test this look at the contact area between the screw head and the blade plate. If the screw is on an angle there will be a gap on one side between the screw and the blade plate.
PBHE uses a Machinist Straight Edge to determine if the blade is straight. Similar to your test at home we hold the Straight Edge against both sides of the blade to determine if the blade is straight. The blade is only set to PBHE's standard when the entire blade length is in contact with the Straight Edge on both sides for parallel blades. On tapered blades the gap on both sides of the blade are equal.
PBHE also evaluated if the screws are flat against the blade plate. PBHE uses a spot level, centre drill, and special stainless steel screws to mount blades which have twice the tensile strength compared to most manufacturers supplied carbon screws.
TEST #2: ARE YOUR BLADES TWISTED?
To determine if your blades are twisted you will need two pencils and a good eye. Balance one pencil horizontally on the two edges of the blade around the spinning area and balance another pencil closer to the back of the blade. These two pencils should be parallel. If they are uneven it means that there is a twist in the blade and/or it was improperly sharpened resulting in uneven edges.
Check to see if there are any gaps between the sole of the boot and the blade plate. Ideally there should be solid contact between the sole and the blade plate without twisting the blade. Unfortunately, without sanding the bottom of the boot and using additional material on the sole it is usually impossible to get full contact. If there is a gap between your blade plate and sole of the boot then you will have spring in the blade and there is a high probability that the blade is twisted as well.
To determine if the blade has any twist PBHE must first determine that the edges are of equal height. PBHE does this by using a Machinist Square and a .001 of an inch Feeler Gauge. Holding the Machinist Square against the stanchions of the blade we can see with the Feeler Guage if both edges are touching the Machinist Square. If both edges are touching the Machinist Square in all tested areas then the edges are even and we can go to the next step. If the edges are not even then the blades need to be sharpened correctly.
Once the edges are even PBHE tests for twist in the blade by using Machinist Parallel Bars. Similar to the Pencil Test you conducted at home we balance the bars around the spinning area and the other closer to the back of the blade. If the Parallel Bars are parallel then there is no twist in the blade.
The sole of the boot and the blade plate must have full contact. In over 18 years we have found that it is extremely rare for a blade to fit perfectly on any boot sole (full contact while blade is just resting on the boot sole without any screws). Due to this, we have developed a special epoxy, Precision Blade Leveling Compound, to level off the sole of the boot so that the blade fits flat with complete contact.
TEST #3: HOW'S YOUR BLADE CURVE?
To examine your blade curve you will need a ruler and a flat surface. First, place your blade on a flat surface, like a table, with your base pick touching the surface. Then take a ruler and measure the distance from the table to the heel of your blade. The heel lift distance should be greater than 3/4 of an inch and no more than 1 and 1/8 of an inch, which takes into consideration various blade length. If the distance is outside of the preferred range your blade curve is not optimal. Heel height should be the same for both blades.
The next indicator of your blade curve is to check the distance between the base pick and the blade's touch point. Again, place your blade on a flat surface, like a table, with your base pick touching the surface. Take a piece of paper and run it along the table starting from the back to the front. At some point, closer to the front of the blade, the piece of paper wont be able to go any further; it will be stopped by the blade touching the table. This is your blade's furthest touch point. Measure the distance from the base pick to this touch point. This distance should be less than 6 centimeters. Touch points should be no more than .5 cm wide on a convex curved surface (your blade). If more than .5 cm is touching the flat surface the blade curve has been flattened.
PBHE has created a special gauge called Figure Skating Blade Curvature Gauge which helps skaters to easily evaluate their blades. The blade is places on the gauge where it is easy to read the blade curve measurements.
PBHE tests the entire blade curve from the base pick to heel by using the manufacturers specifications on master patterns. This is literally an exact model of the ideal blade curve set out by manufacturers that PBHE compares your blade's curve to. This is also what PBHE uses to sharpen skates, making sure they are an exact replica every time!
TEST #4: ARE YOU ON A FIGURE SKATING ROOT?
The root of a blade is the channel between the inside and outside edges. A blades root determines how sharp the edges are which affects how much the edges grip the ice. This is also affected by the skater's weight, skill, and the arena's ice temperature. The root of a blade is measured by the radius of a circle that fits inside the two edges. In general, the larger the radius, the less edge resulting in more side slip (desired by hockey skaters) and the smaller the radius the sharper the edge (given the same blade thickness).
The root of a blade can be measured by coins. Find a coin that sits on top of the blade and does not let any light in between the bottom of the coin and the blade. Once you have found the coin that has full contact with the blade you have found the approximate radius of the current sharpening. Below are the details of Canadian Coins:
- Dime: ~5/16" Radius, Advanced Light Figure Skater
- Penny: ~6/16" Radius, Advanced/Intermediate Skater (Weight and Skill Level Dependent)
- Nickel: ~7/16 Radius, Star Skate Figure Skater, Adult Skaters, Coaches
- Toonie: ~9/16 Radius, Average Hockey Grind, Common grind PBHE finds on New Clients from other retailers
PBHE uses Radius Gauges, which are extremely accurate, to measure a blade's root. There is a wide range of Radius Gauges making it possible to find a measurement that does not allow any light to pass between the gauge and the blade (which is a more accurate measurement).
For educational purposes PBHE completes this test to clients using both Radius Gauges as well as a variety of Honing Stones with various roots, which are visually easier to compare.
If any of these tests fail it is recommended that the blade gets properly sharpened and/or remounted. Re-mounting is a complex procedure that takes approximately 5 hours, which includes 2 hours of epoxy drying time.
PBHE solves these issues by our Blade Mounting process and our one of a kind Pattern Grinding Sharpening. Come in for a consultation and we'll solve your problems!