VTX Tail Blades - New Developments

[rcflyerheli]

I think to a certain extent, every blade is some factor of handmade. Photos were posted of the molds. I don't know the specific details of how the prototypes were made, but it just seems natural to me that in as high risk environment as our hobby is, that more than one prototype pair would have been made.

[3Dmuse]

Originally Posted by cudaboy_71

Ok. There must be more conversation going on somewhere other than here. I was just going by his statement of “a washer over the tail shaft”. I took that to mean the spacer that has been eliminated in the redesign.

Sorry if I’m getting the discussion off track.

FYI see this thread and, in particular, this post that gives you links to other discussions. I did both mods (shimming the tail shaft and using different spacers than stock in the tail grips) and never had a problem in more than 270 flights. First batch kit.

[mc20piece]

Originally Posted by rcflyerheli

I think to a certain extent, every blade is some factor of handmade. Photos were posted of the molds. I don't know the specific details of how the prototypes were made, but it just seems natural to me that in as high risk environment as our hobby is, that more than one prototype pair would have been made.

Go ahead and whip a few sets together and get them shipped out to the pilots.

[Johnny31297]

Bill kept me updated on the blades during their creation. It's not something you "whip together" and ship out.

It's labor intensive, you'll end up with lots of waste material, have to scrap things if they don't work out as planned. I remember that getting to the point where Bill finished the one set I flew, the investment made was about $30,000, with the one set of blades alone being worth about $4,000, considering prototypes made before that, material used, energy required and all the hours of labor.

Now imagine you make 10 sets for testing and have to change anything because a flaw is discovered during testing. Would you rather have a damage of $4,000 for one set or $40,000 for 10?

[GimpyGolden]

Wow, learning that I really wouldn't wanna be 'that guy'

[mmgbrouwers]

Any new developments?

[MikadoUSA]

Financially speaking, all VTX Designs projects were put on hold earlier this year due to requirements of cash flow being allocated to other projects the parent company is involved with. The projects will be picked up again but uncertain exactly when.

[smittylube]

Lets hope they recoup enough to and keep up production of the current line of blades that we all enjoy already.

[mc20piece]

Originally Posted by Johnny31297

Bill kept me updated on the blades during their creation. It's not something you "whip together" and ship out.



It's labor intensive, you'll end up with lots of waste material, have to scrap things if they don't work out as planned. I remember that getting to the point where Bill finished the one set I flew, the investment made was about $30,000, with the one set of blades alone being worth about $4,000, considering prototypes made before that, material used, energy required and all the hours of labor.



Now imagine you make 10 sets for testing and have to change anything because a flaw is discovered during testing. Would you rather have a damage of $4,000 for one set or $40,000 for 10?

You completely missed the sarcasm in my post

[VTX Designs]

Bill here.


The tail blades do have promise for sure. The VTX107 prototype performed amazing when operated inside its envelope. It didn't do so well at elevated speeds - which load up the tail system much more and push the blade beyond its aero envelope. This produces a bad interaction between tail blade aerodynamics and VBAR control logic.



There will need to be a tweak to the airfoil, as well as to the blade tip shape to fix the high speed response. I warned about the first prototype set coming apart at head speeds above 2000 rpm. Of course, they were spun up well above that (not by Johnny - he did just fine), which did reveal compressibility issues (as predicted). Unfortunately, I wasn't present when the adverse response was observed, so a good deal of my feedback here is nothing short of guess work.



I hope y'all have taken note of how much space has been given in the "aero engineering" thread talking about issues associated with high mach aerodynamics ... and here we have yet another example of that monster rearing its head. I think I pushed just a little too far with this prototype design. Doing upwards ot M.65 with a blade chord of around 1/2" is simply ridiculous. The VTX107 as designed would suit 90-95% of the flyers out there perfectly, if RPM is kept under control.


So now its back to financial thrust. The tail blade project will require another set of tooling to be modeled, CNC'd, polished, fixtured and jigged. Then all the time to hand lay-up a single blade set. Its my own process - admittedly this is the first time I've ever built anything like this.


The skins are actually done in a miniature autoclave process, to squeeze every .001 gram of weight out, and to ensure perfect geometry with very high interlaminar compression in the mold. The results are stunning, but massively time consuming. In this first prototype set, I had issues with blade weights not exactly matching so in the lighter blade a small steel plug was potted in to balance it out. And of course, the weight got spit out when RPM was pushed too high.


Anyway, that's where we are at this time. Project on hold.

[落琅heli]

It is great to see someone push forward RC helicopter aerodynamics.