Blackstone Flat-Bottom V Thread

[AfftonDad 88]

If referring to me, your ramblings are just fine....it is all good info. I just started to get a headache while reading it. My opinion of FBV is developed purely from feel. I skate over 7 hours per week. I let my feet do the talking when it comes to reviewing FBV and determining what feels best. You like to go deeper and that is just fine, I was just being sarcastic.

No I was referring to me and my tendency to get long winded. Going through life as an engineer is a curse brother... you have to analyze EVERYTHING!

[NuggyBuggy 0]

But it is implying bite.

Why make a complicated shape for someone to have the same feeling they had before?

Like I've told everyone who has tried FBV - you will have something that will remain constant, and you will gain something you didn't have before.

So, for some people (not many), you match the glide. But now, they have gained bite.

For most people, you match the bite, but they have gained glide.

JR, I think that is a great way for people to think about this. It has already helped me. Thanks.

At the risk of being dense, can you define "bite" ?

I'm asking because I had been skating on 90/75, and liked it. I decided I wanted to try the 95/50, and finally did, with the help of Steve's table. What I seemed to notice was that my skates felt great in turns and stops, but sprinting in a straight line, I felt slow, like I couldn't dig in. It wasn't that my edges weren't slipping, I just felt like I wasn't going anywhere. When I wasn't pushing, the glide felt fine.

I would have thought that the ability to hold an edge in a turn and the ability to grab the ice in a straight line would have been correlated and that this was what someone would typically refer to as "bite".

Does what I experienced make any sense ?

[AfftonDad 88]

JR, I think that is a great way for people to think about this. It has already helped me. Thanks.

At the risk of being dense, can you define "bite" ?

I'm asking because I had been skating on 90/75, and liked it. I decided I wanted to try the 95/50, and finally did, with the help of Steve's table. What I seemed to notice was that my skates felt great in turns and stops, but sprinting in a straight line, I felt slow, like I couldn't dig in. It wasn't that my edges weren't slipping, I just felt like I wasn't going anywhere. When I wasn't pushing, the glide felt fine.

I would have thought that the ability to hold an edge in a turn and the ability to grab the ice in a straight line would have been correlated and that this was what someone would typically refer to as "bite".

Does what I experienced make any sense ?

In my opinion what most people would call bite comes predominantly from two things in FBV. 1) Edge angle and 2)Edge depth. How deep the blade is in the ice relates mostly to how well you can push. The edge angle relates greatly to how hard you can turn and how hard it is to go from pushing to scraping ice (hockey stopping, doing mohawk transitions, etc). You went from a depth of 0.75 to 0.50 and an edge angle of 85.7 to 87.1 (the way that blackstone is calculating edge angles in the "technical specs" doc means that bigger edge angle numbers are actually less bite, with 90 degrees being "no bite at all". So you decreased your "bite" in both of the changes you made, which is what you were trying to do (if you were trying to go faster). FBV doesn't eliminate the reality of the tradeoff between bite and glide. They just lessoned how much of one you have to give up to get more of the other. But that was one of the correct two to try if you were tryig to go faster while minimizing the change to bite.

Speed is determined by Flat bottom width and Edge Depth

"Grip" is determined by Edge Angle and Edge Depth.

The interdependency comes from the fact that blade width is fixed and that you therefore can not change any single one of those (edge depth, edge angle, or flat bottom width) without changing one of the other two.

Edited July 23, 2010 by AfftonDad

[AfftonDad 88]

This is the chart I'm putting on the wall by my sharpener...

Edited July 23, 2010 by AfftonDad

[NuggyBuggy 0]

So you decreased your "bite" in both of the changes you made, which is what you were trying to do (if you were trying to go faster). FBV doesn't eliminate the reality of the tradeoff between bite and glide. They just lessoned how much of one you have to give up to get more of the other.

If you were trying to go faster and trying to maintain the "bite" that you had, you would have wanted to go to 100/50, because the edge angle is that of 1/2 inch (as was 90/75) as indicated by the new chart. HOWEVER, even in that case you would still be lessening your "bite" some because you would have less edge IN the ice. What were you trying to "gain"? Remember, even in FBV you are still going to give up something anytime you try to gain something else, the tradeoff just isn't as severe as with ROH.

AfftonDad - I was trying to gain a little more glide. I was more than happy with the bite I was getting. Right now I am satisfied with the performance in turns, stopping, etc, but not happy with the push I am getting. Your analysis suggests that what I want to do is increase my edge depth from 95/50 but keep the edge angle the same. Now I guess I just need to work up the edge angles for the full set of FBVs and figure out where to go next.

[NuggyBuggy 0]

This is the chart I'm putting on the wall by my sharpener...

Nice ! I was just going to work up the angles myself. So - to selfishly get back to my question - if I was at 90/75, liked it but wanted a bit more glide, tried 95/50 and wasn't get enough push but was fine in turns - then I'd want to retain my edge depth at 75 but could try a larger numbered edge angle - maybe 85/75 or 80/75 ?

Crap ! Just checked, it seems like they don't have either FBV in a mini-spinner, but I'm sure they had other spinners on their website a few days ago - I KNOW they had the 95/50, because I ordered one. That's weird.

[jcp2 2]

Speed is determined by Flat bottom width and Edge Depth

"Grip" is determined by Edge Angle and Edge Depth.

I think "Glide" is a better term than speed, and that it is dependent primarily on the width of the flat surface. The bit of edge in the ice seems pretty small to significantly affect the glide. Edge angle and depth is definitely important for grip, but blade angle to the ice and the force applied applied to the blade is really important as well. For FBV, I would think that going to a higher edge angle and depth would cost little in speed; the trade-off would be in the smoothness of the transition from glide to grip and the amount of forgiveness for less than perfect technique. In fact, technique would be even more important, as with a traditional hollow system, a grippier sharpening is also a slower sharpening, whereas in FBV, a grippier sharpening can be a faster sharpening.

[AfftonDad 88]

AfftonDad - I was trying to gain a little more glide. I was more than happy with the bite I was getting. Right now I am satisfied with the performance in turns, stopping, etc, but not happy with the push I am getting. Your analysis suggests that what I want to do is increase my edge depth from 95/50 but keep the edge angle the same. Now I guess I just need to work up the edge angles for the full set of FBVs and figure out where to go next.

The following IS NOT based on any first hand knowledge of those FBVs but rather just what changes are being made to the shape.

Well lets see (and forgive me if I make a mistake, it's a lot to keep straight)...

If you were at 90/75 you could move to one of four (assuming you had all of the choices in the chart and you were only going to move one position at a time).

NOTE: For each item listed I don't mean one of them will happen, I mean ALL of them will happen

If you went to 85/75

-You would increase drag due to the smaller flat bottom width

-You would maintain the same drag due to the same edge depth in the ice

-You would maintain the same pushing ability due to the same edge depth in the ice

-You would decrease pushing ability due to the less sharp edge angle

-You would maintain cornering ability due to the same edge depth in the ice

-You would decrease cornering ability due to the less sharp edge angle

-You would increase your ability to easily scrape ice (stop, mowhawks, etc.) due to less sharp edge angle.

-You would maintain your ability to easily scrape ice (stop, mowhawks, etc.) due to less edge depth in the ice.

If you went to 90/50

-You would maintain the same drag due to the same flat bottom width

-You would decrease drag due to less edge depth in the ice

-You would decrease pushing ability due to less edge in the ice

-You would decrease pushing ability due to a less sharp edge angle

-You would decrease your cornering ability due to less edge depth in the ice

-You would decrease your cornering ability due to a less sharp edge angle

-You would increase your ability to easily scrape ice (stops, mohawks, etc.) due to less sharp edge angle

-You would increase your ability to easily scrape ice (stop, mowhawks, etc.) due to less edge depth in the ice.

If you went to 95/75

-You would decrease drag due to a bigger flat bottom width

-You would maintain the same drag due to the same edge depth in the ice

-You would maintain the same pushing ability due to the same edge depth in the ice

-You would increase pushing ability due to a sharper edge angle

-You would maintain your cornering ability due to the same edge depth in the ice

-You would increase your cornering ability due to a sharper edge angle

-You would decrease your ability to easily scrape ice (stops, mohawks, etc.) due to sharper edge angle

-You would maintain your ability to easily scrape ice (stop, mowhawks, etc.) due to the same edge depth in the ice.

If you went to 90/100

-You would maintain the same drag due to the same flat bottom width

-You would increase drag due to more edge depth in the ice

-You would increase pushing ability due to more edge depth in the ice

-You would increase pushing ability due to a sharper edge angle

-You would increase your cornering ability due to more edge depth in the ice

-You would increase your cornering ability due to a sharper edge angle

-You would decrease your ability to easily scrape ice (stops, mohawks, etc.) due to sharper edge angle

-You would decrease your ability to easily scrape ice (stop, mowhawks, etc.) due to more edge depth in the ice.

So like I said before it's not that simple. I would think you definately wouldn't want to bother with 85/75 because it doesn't have any speed increasing attributes. As for the other three, unless one of them jumps out at you as "yeah that sounds like what I need" then I think it is going to be a trial and error proposition.

Now some of those attributes are probably much less significant when compared to the others which would mean that you could ignore them. I don't have a clue which ones would fall into that category. I'm sure that is some of the things they are looking at in Blackstone's university study.

Now when someone someday figures out how to dynamically vary blade width... that will be very sweet... think perfectly, individually optimized hollows...

Edited July 24, 2010 by AfftonDad

[AfftonDad 88]

I think "Glide" is a better term than speed, and that it is dependent primarily on the width of the flat surface. The bit of edge in the ice seems pretty small to significantly affect the glide. Edge angle and depth is definitely important for grip, but blade angle to the ice and the force applied applied to the blade is really important as well. For FBV, I would think that going to a higher edge angle and depth would cost little in speed; the trade-off would be in the smoothness of the transition from glide to grip and the amount of forgiveness for less than perfect technique. In fact, technique would be even more important, as with a traditional hollow system, a grippier sharpening is also a slower sharpening, whereas in FBV, a grippier sharpening can be a faster sharpening.

Yeah... I know what you mean. I inentionally chose speed though. I associate glide with the absence of drag. I was actually using "speed" to differentiate (at least in my own mind) from the absence of drag. If you can glide really well, but can't get anything out of your stride, you would not be fast. A cross ground skate would have GREAT glide, but I doubt the player would be very fast. As I said in my last post, I am pretty certain that some of the factors are much less significant, but I wouldn't want to speculate on which ones without any data to back it up. I'm hoping blackstone will enlighten us with the university data. If Blackstone is really going to have that many FBV's, I was thinking... I could envision a computer program (I'm a software person) that Blackstone could make available to LHS's and us home sharpeners that would allow input of height, weight, position, age, some skating style aspects, skate model, desired attribute's, etc and the software would poop out a suggested FBV. That would be a VERY complicated physics model to pull off though.

Incidentally, does anyone know how a speed skate works? I've always been told they were flat. How can they skate so fast if that is true?

Edited July 24, 2010 by AfftonDad

[mnpucker 33]

Not a ton of technical data here but it is a start. think they are flat as well. It appears the bur is simply turned up.

Edited July 24, 2010 by mnpucker

[AfftonDad 88]

Nice ! I was just going to work up the angles myself. So - to selfishly get back to my question - if I was at 90/75, liked it but wanted a bit more glide, tried 95/50 and wasn't get enough push but was fine in turns - then I'd want to retain my edge depth at 75 but could try a larger numbered edge angle - maybe 85/75 or 80/75 ?

Crap ! Just checked, it seems like they don't have either FBV in a mini-spinner, but I'm sure they had other spinners on their website a few days ago - I KNOW they had the 95/50, because I ordered one. That's weird.

BTW... I never answered the specific question that you asked (I made a spread sheet where I can just enter the FBV values and it will output the INCREASE/DECREASE stuff to make it easy on myself... I can send it to you if you would like)

Going from 90/50 to 80/75

Glide due to flat bottom width	                     DECREASE
Glide due to edge depth	                             DECREASE
Pushing/Cornering ability due to edge depth          INCREASE
Pushing/Cornering ability due to edge angle          SAME
Transition to stop, mohawk, etc. due to edge depth   HARDER
Transition to stop, mohawk, etc. due to edge angle   SAME

Going from 90/50 to 85/75

Glide due to flat bottom width                       DECREASE
Glide due to edge depth                              DECREASE
Pushing/Cornering ability due to edge depth          INCREASE
Pushing/Cornering ability due to edge angle          INCREASE
Transition to stop, mohawk, etc. due to edge depth   HARDER
Transition to stop, mohawk, etc. due to edge angle   HARDER

Going from 90/50 to 95/75

Glide due to flat bottom width                       INCREASE
Glide due to edge depth	                             DECREASE
Pushing/Cornering ability due to edge depth          INCREASE
Pushing/Cornering ability due to edge angle          INCREASE
Transition to stop, mohawk, etc. due to edge depth   HARDER
Transition to stop, mohawk, etc. due to edge angle   HARDER

Going from 90/75 to 80/75

Glide due to flat bottom width	                     DECREASE
Glide due to edge depth                              SAME
Pushing/Cornering ability due to edge depth          SAME
Pushing/Cornering ability due to edge angle          DECREASE
Transition to stop, mohawk, etc. due to edge depth   SAME
Transition to stop, mohawk, etc. due to edge angle   EASIER

Going from 90/75 to 85/75

Glide due to flat bottom width                       DECREASE
Glide due to edge depth                              SAME
Pushing/Cornering ability due to edge depth          SAME
Pushing/Cornering ability due to edge angle          DECREASE
Transition to stop, mohawk, etc. due to edge depth   SAME
Transition to stop, mohawk, etc. due to edge angle   EASIER

Going from 90/75 to 95/75

Glide due to flat bottom width                       INCREASE
Glide due to edge depth                              SAME
Pushing/Cornering ability due to edge depth          SAME
Pushing/Cornering ability due to edge angle          INCREASE
Transition to stop, mohawk, etc. due to edge depth   SAME
Transition to stop, mohawk, etc. due to edge angle   HARDER

Edited July 24, 2010 by AfftonDad

[AfftonDad 88]

Not a ton of technical data here but it is a start. think they are flat as well. It appears the bur is simply turned up.

That's interesting... Thats what FBV moves us closer to... a flat blade with a little burr (sort of) on the edge. That makes sense though. They don't need edge control and therefore don't need any edge angle or V, because they don't have to hockey stop and do transitions. So they just need little runners like the old metal sleds. Seems to me blackstone could enter the speed skate sharpening market as well (not that there is much money in it) by making some special shaped spinners, like this [ , to do the job for them as well.

Edited July 24, 2010 by AfftonDad

[AfftonDad 88]

I've always believed that the edge on my skates are not as sharp (and I mean cut your finger sharp, not depth of hollow sharp) on my X-01 as what they are able to do at the LHS. I just got my first "ruby" wheel and unless I am imagining it, that was the difference. It feels much more "cut your finger" sharp to me. I don't know if that is going to turn out to be a good thing or a bad thing though (I don't want to have to do the old rub the skates on the plastic at the bench door trick again).

Now, what to do with my extra orange wheels?

On another topic, I'm starting to hear a new noise out of my sharpener (sort of an extra vibration that comes and goes). I hope it isn't a bearing going. Anyone else have such a sound? Do any of you do any regular maintenance on your X-01 other than just wiping down and vacuuming off?

[mnpucker 33]

I've always believed that the edge on my skates are not as sharp (and I mean cut your finger sharp, not depth of hollow sharp) on my X-01 as what they are able to do at the LHS. I just got my first "ruby" wheel and unless I am imagining it, that was the difference. It feels much more "cut your finger" sharp to me. I don't know if that is going to turn out to be a good thing or a bad thing though (I don't want to have to do the old rub the skates on the plastic at the bench door trick again).

Now, what to do with my extra orange wheels?

On another topic, I'm starting to hear a new noise out of my sharpener (sort of an extra vibration that comes and goes). I hope it isn't a bearing going. Anyone else have such a sound? Do any of you do any regular maintenance on your X-01 other than just wiping down and vacuuming off?

Does the noise also create any kind of chatter marks on your blade? I have had a noise that sounds more like a moan to me....I just vacuum and keep it clean.

[AfftonDad 88]

Does the noise also create any kind of chatter marks on your blade? I have had a noise that sounds more like a moan to me....I just vacuum and keep it clean.

No "extra" chatter marks. I always end up with a little fish scale until I do my final passes. I hear a bit of "moaning" as I go through the middle section of the blade but that is unrelated to the sound I am talking about and I had never heard that until yesterday either. I associated that moaning with being related to the ruby wheel because I also heard it for the first time yesterday but I suppose that could have been there for a while and masked by the vacuum as well. Except for in the very begining, when I know I didn't have either noise, I always ran it with the vacuum and couldn't hear anything. The noise sounds like a little vibration. I think it is either 1) Something has loosened up and is vibrating, 2) A bearing is going, 3) some grit has worked its way into the motor.

[rachael7 1]

Maybe your new wheel isn't quite round yet? Sometimes there is a slight eccentricity that takes a few dressings to fully resolve. You could rotate the wheel by hand (with the machine unplugged, obviously) and see if there is any variation in the markings. If so, a couple more dressings might take care of it.

[mnpucker 33]

Maybe your new wheel isn't quite round yet? Sometimes there is a slight eccentricity that takes a few dressings to fully resolve. You could rotate the wheel by hand (with the machine unplugged, obviously) and see if there is any variation in the markings. If so, a couple more dressings might take care of it.

I agree wtih Rachel that it does take some time to round the wheel. But I too have the moaning sound from time to time and it begins at the same time you mentioned (mid protion of the blade). I have no answers for you however. Sometimes it is there and then it goes away.

[AfftonDad 88]

Maybe your new wheel isn't quite round yet? Sometimes there is a slight eccentricity that takes a few dressings to fully resolve. You could rotate the wheel by hand (with the machine unplugged, obviously) and see if there is any variation in the markings. If so, a couple more dressings might take care of it.

Do you mean for the moaning noise or the other noise? The other (sort of vibrating noise) is definately not the wheel because it happens when the wheel is off (I took it off to make sure). I'm not that worried about the moaning noise. I think it is just due to a difference in the composition of the ruby wheel. I do a pretty substantial dress when I put on a brand new wheel, marking with a marker around the entire wheel so that I can be sure I dressed it completely.

[fastmiele 59]

I saw this free skate sharpening ad for Sportchek, up to 3 pairs of skates - August 4 - 30th.

I don't know about the quality but it is free.

http://img5.imageshack.us/i/dsc03922r.jpg/

Edited August 10, 2010 by fastmiele

[kevrocks 1]

I'm not sure if I found a general consensus, but is there a general consensus for whether FBV will require more frequent sharpenings compared to ROH, assuming the same playing conditions?

[chiefs17 2]

I'm not sure if I found a general consensus, but is there a general consensus for whether FBV will require more frequent sharpenings compared to ROH, assuming the same playing conditions?

kevrocks, technically I suppose the FBV should last as long as an ROH sharpening, but it's been my experience that it does not. I also think it is a more fragile edge, so you are more susceptible to getting nicks and flat spots in the edge. I also think that once the edge is dull, it's a big drop off in sharpness. On an ROH edge you can get by with a less than perfect edge and not notice it as much.

I think this is also dependent on all of the variables associated with skate blade sharpness. Things like which ROH vs which FBV, player weight/style, ice conditions, etc.

[Law Goalie 147]

Possibly a dumb question, but has anyone tried 105/75?-- or is that only physically possible with wider goalie blades?

[rachael7 1]

Possibly a dumb question, but has anyone tried 105/75?-- or is that only physically possible with wider goalie blades?

Definitely a goalie-only sharpen. Might be physically possible on a player blade, but just barely; the edges would be close to non-existent.

[jcp2 2]

kevrocks, technically I suppose the FBV should last as long as an ROH sharpening, but it's been my experience that it does not. I also think it is a more fragile edge, so you are more susceptible to getting nicks and flat spots in the edge. I also think that once the edge is dull, it's a big drop off in sharpness. On an ROH edge you can get by with a less than perfect edge and not notice it as much.

I think this is also dependent on all of the variables associated with skate blade sharpness. Things like which ROH vs which FBV, player weight/style, ice conditions, etc.

My FBV lasts longer (100/50) than my regular sharpening, but I'm more of a coaster(I play D). I've been able to use the extra glide to save my energy when reacting to the play, and sharp cuts and stops are not part of my regular game.

[Law Goalie 147]

Definitely a goalie-only sharpen. Might be physically possible on a player blade, but just barely; the edges would be close to non-existent.

That's what I figured. I know they said 110 was impossible on player blades.

Anyone tried 100/1 other than Tim Thomas and a couple of jimmy's experimental guys?