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Author Topic: Why Graf (and other?) blades don't countersink mounting holes?  (Read 2388 times)

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Offline Query

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Some Graf figure skating blades are very expensive, yet, AFAICT from pictures and a brief phone call to Graf/Canada, none of them have countersunk holes. (A countersunk hole has an inverted cone shape at the top of the hole, that meshes with the cone shape at the top of a suitable countersink-head screw. Countersinks firmly lock a mounting plate to the base [in this case the outsole] in a specific horizontal position.)

Since screws generally have a significantly smaller diameter than the hole, a lack of a countersink means that if the screw comes even a little loose, the blade could shift horizontally, creating problems for the skater.

Are there any other high level blades that make this mistake?

Have I got this wrong? E.g., do the Graf mounting plates actually have threaded holes that the threads of the screw fit into?

Many low level figure skating blades aren't countersunk either - but I think they are meant to be held in place by rivets which are the same diameter as the hole.

P.S.: I'm not sure if my use of the term "screw" is correct. Based on catalog pictures, Graf screws are technically bolts, because they aren't self-tapping.

Offline nicklaszlo

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Re: Why Graf (and other?) blades don't countersink mounting holes?
« Reply #1 on: April 15, 2015, 11:14:55 PM »
Probably it is so you can fine tune the position of the blade after you have made the hole for the screw.

Offline amy1984

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Re: Why Graf (and other?) blades don't countersink mounting holes?
« Reply #2 on: April 16, 2015, 01:30:22 AM »
I wouldn't call it a mistake.  It's done purposefully to allow adjusting of the blade.  When I first got my blades (another brand) on, they only used the slider holes and told me to come back and get them adjusted or come back and get the rest of the screws.  The lady who did them said that lots of people don't come back and are skating around on skates without the permanent screws in and no one has lost a blade yet.  Not that I would suggest you do this, lol.  Just trying to point out what they're used for and that not having them counter sunk isn't the end of the world.

Offline lutefisk

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Re: Why Graf (and other?) blades don't countersink mounting holes?
« Reply #3 on: April 16, 2015, 08:54:59 AM »
I wouldn't call it a mistake.  It's done purposefully to allow adjusting of the blade.  When I first got my blades (another brand) on, they only used the slider holes and told me to come back and get them adjusted or come back and get the rest of the screws.  The lady who did them said that lots of people don't come back and are skating around on skates without the permanent screws in and no one has lost a blade yet.  Not that I would suggest you do this, lol.  Just trying to point out what they're used for and that not having them counter sunk isn't the end of the world.

I wouldn't want to jump, especially not a toe pick assisted jump, on skates without a couple permanent screws per blade.

Offline sarahspins

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Re: Why Graf (and other?) blades don't countersink mounting holes?
« Reply #4 on: April 16, 2015, 10:33:41 PM »
I wouldn't want to jump, especially not a toe pick assisted jump, on skates without a couple permanent screws per blade.

I've done it with just an added screw at the toe before adding more.  My understanding though, is that on a VERY temporary basis, like just a session or two, the risks are really minimal - and especially for a skater doing higher level jumps, you need to be able to fully evaluate your blade position before committing to a permanent mount.

One of our old fitters (she moved away, AFIAK still doing fittings) was 100% comfortable with skaters doing triples on a temp mount to confirm blade position.  It's only continuing to do them that is iffy.

Offline amy1984

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Re: Why Graf (and other?) blades don't countersink mounting holes?
« Reply #5 on: April 17, 2015, 12:30:17 AM »
I've done it with just an added screw at the toe before adding more.  My understanding though, is that on a VERY temporary basis, like just a session or two, the risks are really minimal - and especially for a skater doing higher level jumps, you need to be able to fully evaluate your blade position before committing to a permanent mount.

One of our old fitters (she moved away, AFIAK still doing fittings) was 100% comfortable with skaters doing triples on a temp mount to confirm blade position.  It's only continuing to do them that is iffy.

I've done it on a limited basis but usually with one of the toe screws in.  I think it's important to remember that the kids skating around without the permanent screws in are probably half my size.  I also think that as adults we are probably a bit more cautious.  Like I said, I wouldn't recommend it but apparently lots of people do it.

Offline Query

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Re: Why Graf (and other?) blades don't countersink mounting holes?
« Reply #6 on: April 17, 2015, 03:05:15 PM »
It's not just a question of losing the blade - the position can also shift gradually.

If the screws are very tight (right on the edge of stripping the holes), I think the blades probably won't shift for one or two jumps - but it's hard to imagine doing so long term.

The Graf Edmonton skates I am using now (didn't include blades) has an extremely rigid outsole, which would probably accept a pretty tight screw without stripping. I have tried a few half rotation jumps in the test mount, without loss. In fact, when I put in the test mount (non-Graf self-tapping) screws without pilot holes (shame on me!), the outsole literally bulged outwards there, and I had to sand it to be level again.

Then again, I don't know how wide Graf's screws are. If they are beefy enough, maybe nothing comes lose. But the catalog only suggest a 2 to 2.5 mm pilot hole. (See page 5.)