4 days ago this was posted on https://www.facebook.com/bowieicearena

QuoteThe City of Bowie, Maryland requests proposals from qualified and experienced firms to provide Construction Management Services for all aspects of construction of a new single sheet ice arena located at 7800 Laurel Bowie Road, Bowie, Maryland, 20715.

The new rink design info is at https://www.cityofbowie.org/841/New-Proposed-Bowie-Ice-Arena-2024.

I have no additional pertinent information. But given the recent maintenance issues at the current site, it is important that something newer be built soon.

There does not appear to be a safe, practical way for pedestrians or bicycles to get across route 197 from the south or east of the site - not even for kids at the elementary school, directly across 197 from the proposed site, or for that matter from the senior center just south of it. I would love it if routes were be provided, along with a light with a pushable button for pedestrians or bicycles crossing 197, and/or a pedestrian bridge across 197.

Quote from: Query on October 29, 2024, 02:35:57 PM
E.g., I have no problem telling by eye that my main rockers are closer to 8' than to 7' 9" or 8' 3".

You started off this thread by demonstrating how difficult it is to visually perceive the difference between a 7' vs 8' radius rocker.  But now you claim you can readily visually perceive the difference between an 8' vs 7'9" vs 8'3" rocker.  Huh?

Quote from: tstop4me on October 29, 2024, 06:25:41 AM
I only went by the manufacturers' specifications for the main rocker radius (7' for Coronation Ace and Aurora vs 8' for Paramount).  I have no tools for measuring rocker radius.

I have some rocker curves at http://mgrunes.com/boots/DrawArcs.

If you print them (e.g., using Microsoft Paint), and manage to convince your print driver to print them at a scale that the inch scales on the borders are correctly scaled (most print drivers and software do rescale by default, even if you tell them not to - which I hate), then you can easily place them behind your blades (fold the paper to get it out of the way of your boots and mounting plate and see). E.g., I have no problem telling by eye that my main rockers are closer to 8' than to 7' 9" or 8' 3". I couldn't be certain by eye whether my spin rockers were 9 inches or 10 inches, but think 9".

BTW, shortly after buying my Matrix (I) runners, I called Jackson Ultima and asked them whether the Matrix runners had the same shape as their non-Matrix blades with the same model names (Ultima Matrix Supreme, Dance, Synchro). They couldn't or wouldn't answer the question. When the MK/JW Revolution blades came out I asked HD Sports a similar question, and didn't get an answer for that either. Such basic questions...

At least in my case, Ultima spin rockers are NOT flatter than most MK or JW spin rockers (about 9" for me). But the spin rocker segment is short. So the distance between the back part of the spin rocker, and the touch point (in high school geometry we called it a tangent point), which many skaters like to spend most of their time between, is also short. True whether you measure it horizontally, vertically, or along the curve.

Quote from: Kaitsu on October 28, 2024, 01:41:36 PM
Which blades you had when your noted this difference?
Was the supplier specification and skating feeling the only ways you used verify rocker radiuses or did you use some measurement method to ensure which were the actual radiuses in your blades?

For many years I skated on Wilson Coronation Ace (plain carbon steel).  Then I switched to Eclipse Aurora (440C stainless).  It was supposed to be the same profile as the Coronation Ace, but not quite.  I didn't notice any difference in glide on the main rocker, but the spin rocker was flatter.  I skated on them for less than a year.

I then switched to the Paramount version of the Gold Seal, what they refer to as the 12" spin rocker model (440C stainless).  They claim it has the same spin rocker and main rocker profile as the Gold Seal. The Paramount runner has parallel sides; no concave side honing, no tapered blade thickness as in the Gold Seal.

I only went by the manufacturers' specifications for the main rocker radius (7' for Coronation Ace and Aurora vs 8' for Paramount).  I have no tools for measuring rocker radius.

I switched from JW Coronation Ace to MK Dance when I was almost a beginner, stayed with them for a long while, then to Jackson Ultima Matrix (1 - not the current Matrix models). The Ultima blades included many runners of Ultima Dance, and one pair of runners for Ultima Supreme and Ultima Synchro.

I did not record the Coronation Ace profile. I didn't record the MK Dance profile until until they were fairly old. A good skate tech told me I had modified the MK Dance profile without intending to. I didn't understand sharpening well enough when I started sharpening the MK Dance to record the profile.

I did look at the rocker profiles of the Ultima Matrix 1 runners when they were new. All seemed to my eye to have the same profile (all 3 models!), except for the toepick. I don't know if that is true of modern Ultima blades. But a lot of figure skaters greatly prefer the MK or JW blades, as you must know.

So I can't be very helpful to you there. I'm not sure I could convince a shop owner to let me walk in and trace many blades. Especially if they knew I had considered making my own, and did sharpen my own! Sorry!

Most 3D printers don't shape very consistently, and don't use hard enough materials.

All the figure skaters I know use two blades. 

Another way to think of the rocker segments having the same tangent: Picture two circles, one completely circle inside the other, except at one point, which they share. An arc of the larger circle is the main rocker segment, and the smaller circle is the spin rocker, meeting at the point the circles share.

Maybe a professional grade jig saw would work well - if you use or make a circle cutting jig and clamp while you change radii. And a strip cutting jig for the toepick. Most good jig sa ws let you adjust the cut angle so you could make cross-picks, if desired.

If you have the money or shop access, a CNC cutter might do it too.

Do you have the skills to harden the edge after it is cut? Or if you start with hardened steel (so you need a laser cutter), to temper the rest of the blade so it doesn't shatter?

Appropriate alloy smooth uniform thickness sheet steel that is soft enough to cut, is expensive, for your first few failures, and is only available in a few thickness, which might not be right. Maybe a CNC cutter could effectively mill the blade near the edge to the right thickness.

If you don't use a stainless steel like 440C, you will probably need to plate the metal with nickel (nickel/chromium if you want it shiny like MK & JW), to slow rust.

Even if you measure just one blade, you have to figure out how blade shape varies with blade length. If the whole blade scale, the radii would scale too. (I don't understand why that isn't done.) Perhaps the fraction along the length of the blade where the blade radii changes stays the same?? And perhaps the relative position of the "touch point", where a straight edge can touch both the back toepick and the curved section of the blade, stays the same??

Since MK/JW blades aren't cut consistently, you might need to measure many blades of each size.

Maybe there are good reasons why only a few companies dominate the high end figure skate blade market. The ideas are easy, but not getting everything right. I apologize for wasting your time with a dumb idea.

They remain closed.

The Facebook page makes it sound like it might be closed for a substantial amount of time. Perhaps the original postings of "a few days" will blow up into a few weeks when all is said and done?? It's already been over a week, and they need to remake the ice after being shipped unspecified hardware. I don't know and haven't been able to get better info. No one I can find is taking phone calls.

The pictures I saw made it look like there was something blue on the ice (??) - maybe one or more pipes carrying refrigerant burst? No data on whether such a pipe would have been from above (those pipes were rusting), or from below. There were some time lapse pictures on one of sites which showed people repainting the floor - but I don't know if that is recent, or from an earlier prep cycle.

The Talbot FSC has posted a note on Bowie's Facebook page inviting Bowie skaters to go to their club sessions at (I think) TFSC rates of $17/hr.

Tucker Road Ice Rink is somewhat closer and cheaper, but beware of traffic jams on the DC Beltway, which sometimes take hours to get through. But sometimes getting to and from Talbot takes hours too, though maybe that is mostly in the summer, for the beach?


Oh well, what can you expect? When the Mayor of Bowie and his followers on the city council decided to cancel the new Bowie Rink, they knew this facility was aging and would have problems. (In the end, cancelling the contracts on that rink, plus cleaning up the site, is costing many times what the mayor claimed - and the new two sheet facility was nominally projected to make more money than it cost to run. I don't know a lot about finances, nor do I have an easy way to review everything involved, but I wish the section around the ice rink, and the area where a replacement could now be built could/would secede and do something about it. There is actually a region of the current park adjacent to the current facility where they could build another sheet, which was proposed at one point - though they would have to cut down a small forest. Another proposed facility a ways north of here, on a golf course, is in the planned Bowie budget. But politics is too complicated for me to understand. And of course there are competing interests for all government activities. Both the old and new proposals look fancier than needed - all that matters to me is the ice. The facility doesn't need to be beautiful.

Continues...
Currently I am printing different templates / radius gauges with 3D printer. They seems to be best method understand how the profile is made, but still its is challenging to verify where one radius ends and another starts. What I know at this stage that it wont make my / our task any easier that even we would have drawings from the manufactures, they seems present the profile which is given to Laser cutting machine. After that at least JW makes few manual grinding phases where they change profiles quite a lot. As its hand made process, each blade is different. Theory and reality are far from each others if profiles are not CNC machined.

I probably publish some video If I manage verify 9.75" P99 profile. Not to drop my motivation, I have focused just to one foot blade. If manage to make template for that one blade, I use same template to another foot blade to show how much they vary from each others...and even from slightly used blades. As said, I am 500% sure that each JW blade is unique, since I measure touch point lengths from all new blades. Therefore we cannot get profile template which would present perfectly example Coronation Ace. Ultima's blades are more dimensionally stable.

I am still working with the profiles. Progress is very slow and from time to time I need to collect some motivation to use this all effort to find out the blade profiles. I have tried quite many methods and none of them has been good. I have 3D scanned brand new blade. Problem in scanning was that mirror shiny surfaces are tricky for optical measuring tools. It causes quite a lot of noise and fake features. Another issue is that STP file is >8gb. My computer and especially graphic card is too weak to process such a huge file.

I have tried to import pencil tracing to CAD software so that I could measure radiuses. I haven't tested profile tracer as I know its even more tricky measuring method than pencil tracing. This because blade does have ROH. I cannot ensure that stylus would travel all the time in same "depth" in the hollow. In both of these methods its nearly impossible to verify where the radiuses ends. When they are not know, also measuring actual radius is difficult.

I have also used also Sid Broadbent rocker radius gauge. Its measuring pins are a bit far from each others to verify radiuses end points. Its has also some measuring uncertainly, especially if hollow is not the middle of the blade. I tried to print other type or rocker gauge which does have ball bearings and it follows the edges, not hollow. It didn't work.

Quote from: tstop4me on October 22, 2024, 06:16:58 PM
When I switched from a 7' to an 8' radius main rocker, the difference was immediately apparent to me.

Which blades you had when your noted this difference?
Was the supplier specification and skating feeling the only ways you used verify rocker radiuses or did you use some measurement method to ensure which were the actual radiuses in your blades?