Balsa blade frequency

[foreright]

Hi all, new here but long time lurker (mainly to look at the gorgeous stuff SDC makes and to gain inspiration xD).

I have a question related to blade making and specifically relating to the frequency of blades with balsa cores. I started making some blades for my own / my son's use a few months ago as he has just started out and I played a long time ago at a decent level (in the smaller ball / speed glue days!) and wanted to start playing again. Seems like a lot has changed since then but the last blade I used "in anger" back then is my trusty TSP Balsa 6.5.

Anyway, I've made up a few blades with different compositions using lightweight balsa (ie. semi-competition stuff) which allowed me to use some more interesting heavier woods for the outer layers. I started with 5/7 ply all-wood construction but feedback from the better players in the club was that they had amazing feel but were a little on the slow side so I've mucked around with CF and Kevlar-CF mix a little bit also with a more "traditional" core material - namely Kiri and those have been better received.

What I've noticed from measuring the "blade frequency" using Audacity is that for the latest Kiri cored, inner CF blades I've made, the figures "make sense" in line with what is reported in the various threads on here - in the 1360 - 1520hz range depending on the outer layers, however for the original 7 or so balsa cored blades I made, the numbers are ridiculous. The ones that people said were "too slow" are coming out in the 1660 - 1800hz range. The one I've loaned out to a fairly highly rated UK player is measuring at around 2000hz and I wouldn't say it's "too fast" (or too stiff for that matter) with nice feel and all wood 7-ply construction. For comparison, my TSP balsa 6.5 measures at around 1920hz and it's listed as OFF speed (by TSP).

Does this make sense? Does this measurement simply not "work" for balsa cored blades - clearly you can measure them against each other and get an idea as to the relative stiffness of them but I guess you can't compare these against more "normally" constructed blades?

 

[SDC]

My advice is: if you don't have the knowledge to answer this question yourself, then forget about frequency. Just build your blades and nevermind the frequency.

I've written about this stuff plenty of times, frequency does not equate speed, but people still don't get it, that's why I stopped posting the frequency along with the specs. To me, as the builder, it has a meaning, to all others it's just a number.

 

[foreright]

Thanks - yes I understand what the number represents in that you're effectively measuring only one "mode" of vibration of a plate, however common knowledge (haha) dictates, and various databases seem to correlate this with the overall "speed" (however you define that...) of the blade in a general sense. Seems to be more related to overall stiffness to me from experimentation. Regardless, my observation / comment is that this relationship, if one exists at all, appears to be completely different when balsa is used as the core material. So my understanding would be that this number would only make sense when comparing blades using a similar construction (ie. core material) - would that be a fair assertion?

Regardless, I am just building and experimenting right now - blades 11 and 12 are in the press right now and just finished up the woodworking on a Tenaly handled Cybershape (no.10 xD) with Hinoki-Ayous-CF-Kiri construction and a much larger handle today.

Personally I find the thickness of balsa cored blades reassuring - I'm actually annoyingly insensitive to the differences between blades also - ie. I can use pretty much anything and find it usable / get used to it really quickly which is likely not a great characteristic for a blade builder xD

 

[SDC]

Not trying to be condescending or anything, but trying to make sense of it without having the base knowledge about modal analysis is not worth it. This is your answer:

I wouldn't bother too much with it, just have fun building blades and experimenting.

 

[Mamba Blades]

The frequency of the racket measures how many times per second the wood vibrates when it is struck. Resonance can influence the feel of the racket, control, and the transfer of energy to the ball, but it is not necessarily directly related to the ball's speed. The frequency has more impact on the sensation and how the shot feels (drier or more controlled) than on the pure speed of the ball.