Blackstone Flat-Bottom V Thread

[AfftonDad 88]

I mark my top knob with a notch to denote thickness.

With the RR I turn the knob counterclockwise 3/4 turn, then clamp the blade. After that if I am not mistaken it is possibly 12 clicks (as it is 6 clicks to get it to move up a line)

Thanks!

[NuggyBuggy 0]

Level of bite has so many factors. How many people could never skate on a 3/8 hollow, yet same skater loves the 100/75. A guide would be nice, but honestly, trial by each skater is the best way.

When I used to skate 10-h a week, I could see that comparing different hollows could work. Now I get a single skate a week, making comparisons almost impossible to do. I'm never going to remember how my skates felt a week ago, so figuring out how to best combine the two FBV parameters to get the best results for me is something I'm never going to have time to do for myself from scratch.

I appreciate the honesty, but Bob, even your website has a guide ! (And yes, I do see the disclaimer at the end). I understand that are no absolutes here, but guys like me need guidance, especially for the FBVs we might be interested in (in my case, thinking about 95/50, coming from 90/75), but which are not documented in existing charts (like Bob's).

If equipment managers really can't figure out how to read the chart or deduce from the FBV nomenclature, it sounds to me like something needs to be done to make the system more understandable, for the regular guys for whom auditioning hollows/FBV is not going to work.

[SAK 2]

When I used to skate 10-h a week, I could see that comparing different hollows could work. Now I get a single skate a week, making comparisons almost impossible to do. I'm never going to remember how my skates felt a week ago, so figuring out how to best combine the two FBV parameters to get the best results for me is something I'm never going to have time to do for myself from scratch.

I appreciate the honesty, but Bob, even your website has a guide ! (And yes, I do see the disclaimer at the end). I understand that are no absolutes here, but guys like me need guidance, especially for the FBVs we might be interested in (in my case, thinking about 95/50, coming from 90/75), but which are not documented in existing charts (like Bob's).

If equipment managers really can't figure out how to read the chart or deduce from the FBV nomenclature, it sounds to me like something needs to be done to make the system more understandable, for the regular guys for whom auditioning hollows/FBV is not going to work.

Nuggy your right....... what we are working on is a slide type of scale (more bite>>>>>>>.......<<<<<<<<<less bite)(more speed>>>>>>>>>>........<<<<<<<<<<<less speed) however there are a lot of variables where it could be integrated, such as goalie skates, figure skates, other types of blades that don't necessarily fall into the "traditional" skate blade. It would be easy to simply but out something which Bob has (which I am not knocking at all) It is just that we want it to be accurate as Bob would appreciate so that he can relate to his customers. As it relates not Bob is correct in saying it is a real personal preference to the individual and we can merely guide you along. I am talking with professional athletes on a daily basis and they are in a similar situation where they want to maximize the benefit of Flat Bottom V, there take on it is interesting, they can feel the difference in the smallest incremental change and they compare it to trying to find the pattern of a stick. I will try to have something put up on our website ASAP. (maybe even today)

[SAK 2]

FBV comparison chart is up. Go to the website WWW.blackstonesport.com it is oon the home site or the technology tab under FBV-ROH comparison. I have a feeling we are opening up a can of questions but it could make for interesting conversation.

[rachael7 1]

FBV comparison chart is up. Go to the website WWW.blackstonesport.com it is oon the home site or the technology tab under FBV-ROH comparison. I have a feeling we are opening up a can of questions but it could make for interesting conversation.

Wow, you ain't kidding. I'm a mechanical engineer, I own an X01, and I use FBV all the time. But that charge just makes me dizzy! And we don't actually have all those options for FBV profiles either, do we?

[NuggyBuggy 0]

I like it ! If I read this correctly, * in general * one would find that e.g. the 95/50 is faster but provides more grip relative to the 90/75 (as an example).

If that's a more-or-less correct interpretation - I'm going to order a 95/50 spinner ASAP !

I also saved the page for perpetuity ;)

Thanks Steve.

[Polarlight 0]

Steve,

Thanks for putting up the profile key. You're right - it does lead to many questions - including:

• Why does second variable go from 1 to .75 to .05?
  
• X-axis makes sense, yet one would expect a correlation between edge and grip on Y-axis - no?
  
• Key suggests those looking for maximum speed and grip can get both with 105-.05. Why don't you just make that spinner and be done with it! :)
  
• What happened to 100/50 and 90/50?
  

I use 90-.75 and it appears 95-.05 is an alternative that offers more speed and better grip, but I admit I'm bewildered.

I have both Blackstone FBV and Blademaster BFD (both used on a Blademaster portable), and appreciate your many choices! Thanks for leading the way. Best wishes!

Edited July 22, 2010 by Polarlight

[AfftonDad 88]

Steve,

Thanks for putting up the profile key. You're right - it does lead to many questions - including:

• Why does second variable go from 1 to .75 to .05?
  
• X-axis makes sense, yet one would expect a correlation between edge and grip on Y-axis - no?
  
• Key suggests those looking for maximum speed and grip can get both with 105-.05. Why don't you just make that spinner and be done with it! :)
  
• What happened to 100/50 and 90/50?
  

I use 90-.75 and it appears 95-.05 is an alternative that offers more speed and better grip, but I admit I'm bewildered.

I have both Blackstone FBV and Blademaster BFD (both used on a Blademaster portable), and appreciate your many choices! Thanks for leading the way. Best wishes!

I think (AND THIS IS ALL PURE SPECULATION ON MY PART AT THIS POINT!!!!)...

1) I think there is a typo and there is a decimal point shift and 0.05 ought to be 0.5. The reason I say this is assuming that 0.75 is the /75 from before .05 would be 15 times less edge depth than 0.75. This would be an EXTREMELY shallow edge (and I suspect that would be an edge depth below the resolution of the holder's knobs to be able control). Furthermore, if you look at the four page technical (original) pdf document, it has the same notation (0.75 vs 0.050) but if you do the math to correlate to the edge angles in the second table on the last page you need to use 0.5 instead of the notated 0.05

In other words

for 100/75

Theta = atan[(0.110-0.100) / (2 * 0.00075)] = 81 deg

(This would represents 100-0.75 and correlates to the edge angle in the 2nd table)

Theta = atan[(0.110-0.100) / (2 * 0.00050)] = 84 deg

(This would represent 100-0.50 and correlates to the edge angle in the 2nd table)

Theta = atan[(0.110-0.100) / (2 * 0.00005)] = 89 deg

(This represents 100-0.05 and DOES NOT correlate to the edge angle in the 2nd table)

So for whatever reason it appears to me (JUST SPECULATION) that there was a typo in that doc that was somehow carried over to the new chart)

2) I think the chart actually represents a 3 dimensional space and that you can't really interpret the newly provided chart as a two dimensional thing. I don't think 100-0.5 would represent the absolute perfect solution for EVERYONE as you suggest. The reason for this is because of that third axis in three dimensional space. Some people might put a higher premium on grip than speed. Some people might put a higher premium on longer lasting edges. The way I interpret the chart you could get more grip from 105-1 than 105-0.5 (but perhaps less fine edge control). On the other hand I think 80-0.5 would have "more glide" than 105-0.5.

There are probably other things that muddy the water as well. As you attempt to go further out on the "Faster" axis, the edge gets shallower. That probably means that you'll have to resharpen more frequently. When you try to go out further on the "More Grip" axis you make the "fangs" more narrow which probably makes them more susceptable to rolling the edges and damage and more susceptable to bent blades and careless sharpeners screwing you up. If you go further out on the less edge axis you probably start getting pushed around in the crease more.

In engineering when you get too many variables to understand adequately you often hold all variables but one constant while varying only one. If there are ever that many FBVs offered and I ever felt it necessaray to get the ABSOLUTE BEST POSSIBLE FBV for me (which god help me, I hope I never do), I would start smack dab in the middle that chart. If there was anything that wasn't satisfactory I would tweak that axis alone until that aspect became satisfactory. Then I would move on to the next axis. It will be however, an interative process. It is like pulling on something that is attached to three different points with rubber bands... You can't pull in any direction without changing the tension on all three axes.

As much as people ask for it though, I don't really think that a chart comparing FBV to ROH is that useful. The reason people ask for that is because they are used to ROH and want to have an FBV that is comparable to what their current ROH feels like. There needs to be a paradigm shift. Isn't the whole point of this that IT IS SUPPOSED TO FEEL DIFFERENT THAN ROH!!! It should feel like you are faster AND have more control. If I wanted it to feel like a 1/2 inch I would have asked for a 1/2 inch!

Sorry for the long post.

[AfftonDad 88]

Paradigm shifts aside, here is that chart sorted by the ROH value that was provided (assuming that my premise on 0.05 vs 0.50 is correct)

105/1.0 ....... 0.13 ... 1/8

107/0.75 ...... 0.13 ... 1/8

105/0.75 ...... 0.19 ... 3/16

100/1.0 ....... 0.25 ... 1/4

105/0.50 ...... 0.25 ... 1/4

100/0.75 ...... 0.38 ... 3/8

95/1.0 ........ 0.44 ... 7/16

90/1.0 ........ 0.53 ... 1/2

95/0.75 ....... 0.53 ... 1/2

100/0.50 ...... 0.53 ... 1/2

85/1.0 ........ 0.69 ... 11/16

90/0.75 ....... 0.75 ... 3/4

80/1.0 ........ 0.81 ... 13/16

95/0.50 ....... 0.88 ... 7/8

75/1.0 ........ 0.94 ... 15/16

85/0.75 ....... 0.94 ... 15/16

80/0.75 ....... 1.13 ... 1 1/8

90/0.50 ....... 1.13 ... 1 1/8

85/0.50 ....... 1.38 ... 1 3/8

80/0.50 ....... 1.63 ... 1 5/8

And a plot of the chart is here...

I'm not saying there is anything revealing here, I just thought some of you might glean something from it.

[AfftonDad 88]

After thinking about it some more (and you guys are gonna kill me for this one)...

I think each FBV may actually sit some place in something GREATER THAN five dimensional space!

1) Pushing Ability

3) Angled Skate Grip

4) Edge Strength

5) Edge Wearability

6) Glide

I would suspect (although I'm not sure) that the one having the least consequence is "Glide". What I mean is that by simply SWITCHING to FBV you jump way far out on the glide axis relative to ROH and that the changes in glide after making that jump are minor and somewhat inconsequential. I would think that "Pushing Ability" is most affected by the depth of the edge. This axis would mostly be about how hard you can push. I think "Angled Skate Grip" would be most affected by the edge angle. This would be mostly about how much do you have to lean a skate before it starts to slip under a given amount of lateral force. Edge Strength would be about how easy it is to roll and edge or nick an edge. This would probably be most related to the edge depth and the edge width. Edge wearability would be about how long you need to go between sharpens (assuming no damage has occured to edge). In other words how long before the edge gets rounded off. I suspect this would be mostly related to the edge height and edge angle. Glide is probably most affected by flat bottom width and edge depth, but as I said earlier, I suspect this is the "factor" that you have the least control over and that at any of the FBVs you have already increased the glide immensely over ROH.

(and I think it actually gets more complicated than above because I think there are actually other variables that would take into account player weight, strength, ankle pronation/supination and ice conditions, etc., and I am DEFINATELY NOT suggesting the someone try to make a visualization of such a complicated multidimensional system)

Now the problem as I see it is, the variables that I have identified are not purely independent variables. There is some interplay between them (at least in terms of the things the we are used to talking about with ROH, namely speed and grip). To bottom line it, I think that there are too many variables and too much interplay to ever make any easy visualation about "what it all means". The bad news of my message is that I'm pretty sure it is going to always be a trial and error propisition. The good news is that there definately should be a combination that will improve your skating (over ROH).

For those of you who have spent time playing with race (car) simulators (like Gran Tourismo), I would liken it to that. There is no scale anywere that says

Less Winning Car <-----------> More Winning Car

There are just many, many car setup parameters and you need to focus on one and then tweak, observe, tweak. And once you get the best performance out of that one parameter for a given conditions, you move to the next and tweak, observe, tweak (keeping in mind that when you are done tweaking this one you may have to go back and repeat the process on ones that you already did). Another analogy would be if you could only play golf with one club, deciding which one you would use. Out of the four clubs that I currently have, I'm sticking with 100/50. My 8 year old son chooses 100/75.

But that's just my opinion. I could be wrong.

Edited July 22, 2010 by AfftonDad

[NuggyBuggy 0]

As much as people ask for it though, I don't really think that a chart comparing FBV to ROH is that useful. The reason people ask for that is because they are used to ROH and want to have an FBV that is comparable to what their current ROH feels like. There needs to be a paradigm shift. Isn't the whole point of this that IT IS SUPPOSED TO FEEL DIFFERENT THAN ROH!!! It should feel like you are faster AND have more control. If I wanted it to feel like a 1/2 inch I would have asked for a 1/2 inch!

The reason I wanted a chart is because, frankly, I wanted to get a little more glide than I'm getting out of my 90/75, but it wasn't clear to me where to go next. With ROH, it's clear where to go from, e.g. 5/8, but I just can't wrap my head around how the 2 parameters in an FBV specification combine.

Now, maybe it is impossible to relate ROH directly to FBV, but what I needed was a heuristic to help me understand the relationship(s) between various FBVs. I think it is next to impossible for guys skating once or twice a week to do meaningful comparisons between different FBVs. I even doubt that most pros - with a sharpener, all the ice time in the world available, and huge incentives - would have the energy to do the full set of comparisons : what would most say to an equipment manager who said "try all these FBVs out and get back to me " ?

This chart helps me understand how the different FBVs relate, and that's all I needed. AfftonDad - even if you are correct in identifying a 5-dimensional space, at least 2 of those dimensions (as pertains to edge strength and wearability) are now largely irrelevant to those of us who are doing our own skates.

Aside: My 95/50 spinner came in and I am hoping to put that on my skates before I play tonight ;)

[mnpucker 33]

Ummm HOLY CRAP! I just want my skates sharpened!! I am dizzy now. When you guys are done let me know what you come up with.....you are making me feel really stupid. hahaha

[Jeff 0]

For you folks in SoCal. I was informed that FBV sharpenings are available in Anaheim at USA Skates 411 West Broadway. Glacial Gardens in Lakewood might have it as well, not sure though.

Looking forward to going there when I get a little free time, can't wait to finally try it out.

[coryroth24 15]

Ummm HOLY CRAP! I just want my skates sharpened!! I am dizzy now. When you guys are done let me know what you come up with.....you are making me feel really stupid. hahaha

+1

[Holy the Goalie 0]

As and aside i have always wondered how if yo start with a blade that has eneven edges how the touch/v-maks work? If say the lower edge is high it will contact the wheel first giving you indications that you do not have the wheel and blade centered where as you may well do it's simply the edge offset. Adjusting the blabe up or down here would encourage you to put the centre of the ROH away from the middle of the blade? A flat grind (crossgrind) with the little dot witness marks in the centre of the steel is obviously spot on but you don't want to cross grind each time.

Can anybody shed some light on this question? I'm looking at the EXACT same issue as TLF (same machine, even), and am having troubles initially getting the blade centered. I end up having to "eyeball" my results and guess as to how much I need to adjust my holder to get good, even edges.

Thanks!

[rachael7 1]

I take my best shot with witness marks and then take a couple passes. Quick knockdown of the burr with a coarse stone (100 grit) and check the edges with my edge checker. Adjust to correct if necessary, another couple of passes if I had to change the holder, then a final pass and 220 grit stone. As was pointed out, witness marks can be deceiving sometimes, so I just do them to make sure I'm in the ballpark. But taking a couple passes and measuring will always let you know where you stand.

Edited July 22, 2010 by rachael7

[JR Boucicaut 3795]

Follow the sparks.

If you're only doing your skates, obviously sharpening immediately will get it dead on from the last one, or at least very close to it.

Coming from another skate, especially one that is uneven, just sharpen and the wheel will always hit the uneven edge first because it is a higher point. Unfortunately, when you do witness marks, what happens is you look at it and you're like "Well, it's not centered, because it hit all the way on the bottom (or top)." Then you adjust, and when you are done, you're left with the opposite result.

I've always said witness marks are only good if you did the previous sharpening. You know the hollow, you know how tight the clamp was, you know the position in the skate holder.

So, sharpen away, and follow the sparks on the wheel. It will give you a good indication on levelness.

[AfftonDad 88]

The reason I wanted a chart is because, frankly, I wanted to get a little more glide than I'm getting out of my 90/75, but it wasn't clear to me where to go next. With ROH, it's clear where to go from, e.g. 5/8, but I just can't wrap my head around how the 2 parameters in an FBV specification combine.

Now, maybe it is impossible to relate ROH directly to FBV, but what I needed was a heuristic to help me understand the relationship(s) between various FBVs. I think it is next to impossible for guys skating once or twice a week to do meaningful comparisons between different FBVs. I even doubt that most pros - with a sharpener, all the ice time in the world available, and huge incentives - would have the energy to do the full set of comparisons : what would most say to an equipment manager who said "try all these FBVs out and get back to me " ?

This chart helps me understand how the different FBVs relate, and that's all I needed. AfftonDad - even if you are correct in identifying a 5-dimensional space, at least 2 of those dimensions (as pertains to edge strength and wearability) are now largely irrelevant to those of us who are doing our own skates.

Aside: My 95/50 spinner came in and I am hoping to put that on my skates before I play tonight ;)

Don't get me wrong. I think the chart with the FBVs on it and the axes labeled on it is great. I just don't think I could ever get much out of the ROHs on the chart, except for perhaps where to start on the chart. However, I contend that if that chart is correct in it's ROH comparisons (and I most definately believe that Blackstone and the university did their due diligence and it is) that someone could go to the chart, pick an FBV that matches their current ROH, say 1/2 inch, try it and say, yep this feels like 1/2", why would I want to pay $4 more for something that feels the same.

I agree about edge strengh and wearability are largely irrelavent to those of use that have sharpeners (as long as they aren't so weak as to catastropically fail in a single skate). I sharpen every 2 or 3 times (I wouldn't if I was taking to a store). If Blackstone ever makes that whole chart available at LHS, that is when you will start seeing players (and employees) heads explode. I hope they don't do that (and I don't think they will). I'm very happy with what I have right now.

Sorry for rambling about this so much. I am on a buisness trip and have time in the hotel room to kill :)

[JR Boucicaut 3795]

While it may feel like 1/2", the difference is it doesn't perform like 1/2".

[Holy the Goalie 0]

JR and Rachel, thank you so much for your quick replies! I'll keep that in mind tonight as I give another pair of skates a go.

[jimmy 194]

Don't get me wrong. I think the chart with the FBVs on it and the axes labeled on it is great. I just don't think I could ever get much out of the ROHs on the chart, except for perhaps where to start on the chart. However, I contend that if that chart is correct in it's ROH comparisons (and I most definately believe that Blackstone and the university did their due diligence and it is) that someone could go to the chart, pick an FBV that matches their current ROH, say 1/2 inch, try it and say, yep this feels like 1/2", why would I want to pay $4 more for something that feels the same.

I agree about edge strengh and wearability are largely irrelavent to those of use that have sharpeners (as long as they aren't so weak as to catastropically fail in a single skate). I sharpen every 2 or 3 times (I wouldn't if I was taking to a store). If Blackstone ever makes that whole chart available at LHS, that is when you will start seeing players (and employees) heads explode. I hope they don't do that (and I don't think they will). I'm very happy with what I have right now.

Sorry for rambling about this so much. I am on a buisness trip and have time in the hotel room to kill :)

Like JR said, it doesn't perform like it's equivalent hollow, what we are talking about when we say "feel" is really about the bite level. Each player has his/her level of bite that they like. All FBVs have great speed, but different bite levels. I've found many who were comfortably skating on a 1/2 hollow who preferred the say the 100/75 (3/8 bite) over the 100/50 (1/2 bite), yet the same person would hate skating on a 3/8 hollow. Go figure. That's why guides are not going to be real accurate, way too many variables.

Edited July 22, 2010 by jimmy

[AfftonDad 88]

Like JR said, it doesn't perform like it's equivalent hollow, what we are talking about when we say "feel" is really about the bite level. Each player has his/her level of bite that they like. All FBVs have great speed, but different bite levels. I've found many who were comfortably skating on a 1/2 hollow who preferred the say the 100/75 (3/8 bite) over the 100/50 (1/2 bite), yet the same person would hate skating on a 3/8 hollow. Go figure. That's why guides are not going to be real accurate, way too many variables.

Now if that is what the ROH comparison implies (i.e. BITE ONLY of 1/2 and NOT glide of 1/2) then that is a different thing entirely than I had thought the chart was trying to imply. That becomes a very useful piece of information and would make the selection process VERY easy for me. I would pick the FBV with the MOST glide and least (shallowest edge) that claims to compare to 1/2 inch (this would be 90/1.00 from the chart). I would be able to pick this because I have a sharpener and can sharpen whenever I need to AND will give the utmost care to edge eveness, etc. If it turns out that I can't even get through a single skate without catastrophically damaging that edge, then I would increase it to the next "more edge" that has the most glide and correlates to 1/2 inch (90/0.75).

What I don't understand though is that after a lifetime of playing hockey, I did in fact settle on a 1/2 inch. So 90/0.75 should be the optimum for me (of the original four that were offered). This is not the case though. I have used 90/0.75 and 100/0.50 extensively and I like 100/0.50 better (because 90/0.75 does't feel like it has enough bite for me and 100/0.50 does, and if the ROH comparison IS truly a "bite only" comparison, the chart says they should feel like they have the same bite). As I stated before though, I don't think it is that simple.

When empirically taking the statistics, if you ask skaters in a large randomized double blind study to try an FBV and "tell me which ROH BITE this FEELS like", I would contend you can't actually get a meaningful answer to that question. I don't think they would be able to separate the two interlated ROH components of bite vs glide.

None of this really matters to me because as I said I have found a great FBV for me and I won't be buying different spinners at $65/per simply for purpose of trial and error to see if I can "squeeze a little more speed" out of it. It would be easier and cheaper to eat a few less donuts.

I'm not knocking anyone or anything. I love FBV. After trying it first at the LHS I voted with my wallet and bought the sharpener, 10+ wheels and 9 mini-spinners (I've only used one spinner up... I do lots of friends skates and whenever I order something from Blackstone I want the free shipping so I order extras and I want to have them on hand right away when I do use them up.)

I feel like I might be upsetting some people and confusing rather than enlightening, so I'll shut up now.

Edited July 23, 2010 by AfftonDad

[JR Boucicaut 3795]

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.

[AfftonDad 88]

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.

OK... and now for an apology from me...

I just realized that I ERRONEOUSLY thought that the chart was a product of the university study and came from empirically asking a group of skaters what ROH a particular FBV felt like. I now realize that the ROH values on the chart come simply from the trigonometric edge angle calculation in the "Technical Specs" document. So after this realization, I agree wholeheartedly that the ROH's in that chart relate in a large and meaningful way to "bite only" and that therefore the chart is a VERY useful tool to help pick which FBV to use. I have always believed that the edge angle is a major contributor (probably the largest contributor) to bite.

I think the rest of my ramblings were valid though.

Steve, JR and Jimmy, I'm on the same page now and I apologize.

[mnpucker 33]

OK... and now for an apology from me...

I just realized that I ERRONEOUSLY thought that the chart was a product of the university study and came from empirically asking a group of skaters what ROH a particular FBV felt like. I now realize that the ROH values on the chart come simply from the trigonometric edge angle calculation in the "Technical Specs" document. So after this realization, I agree wholeheartedly that the ROH's in that chart relate in a large and meaningful way to "bite only" and that therefore the chart is a VERY useful tool to help pick which FBV to use. I have always believed that the edge angle is a major contributor (probably the largest contributor) to bite.

I think the rest of my ramblings were valid though.

Steve, JR and Jimmy, I'm on the same page now and I apologize.

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.