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Author Topic: perky  (Read 2478 times)

Offline bob whitney

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perky
« on: August 04, 2021, 09:33:05 AM »
i hear that there are some changes coming to Perky  any truth to it.getting ready to build a new one  need to know before i start  Rad
rad racer

Online Dennis Toth

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Re: perky
« Reply #1 on: August 05, 2021, 02:09:10 PM »
Bob,
What are the rumored changes?

Best,   DennisT

Offline bob whitney

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Re: perky
« Reply #2 on: August 06, 2021, 12:36:55 AM »
what i heard was 2nd hand i think trying to keep them closer to original
yea inverted was talked about  ,
rad racer

Online Dennis Toth

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Re: perky
« Reply #3 on: August 06, 2021, 07:11:05 AM »
I assume that by eliminating the inverted engine it would remove being able to mount the tank above the needle valve level and require true suction fuel feed rather then gravity assist there by requiring smaller venturi size. This makes sense to eliminate legal cheating. Other option would be to require that the tank be located so that no more than 1/2 it's height is above the needle valve or fuel injector enters the venturi and that the pickup line is on or below the needle valve or injector location as it enters the engine. In other words like a stunt tank setup. Also no variable carbonators and oversize ram air vent lines.

Doing the NVA approach might save some from needing to build new ships, just mod the tank location.

As with everything in speed we all look to fine a legal way around the letter of the rule (if it doesn't say we can't, then we can) and sometimes it is not in line with the intent.

Best,   DennisT

Offline C.T. Schaefer

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Re: perky
« Reply #4 on: August 06, 2021, 07:36:13 AM »
I totally do not understand the reasoning here and who is They?  It is a postal contest anyway.

Online Dennis Toth

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Re: perky
« Reply #5 on: August 06, 2021, 08:31:54 AM »
CT,
You have one of the fastest ships with the inverted engine congrats on the NAEs win. I do think the fuss is about having gravity feed into the inverted engine allowing a larger venturi and not true suction and that not being in the sprit of the events intent. I know part of the fun is to fine ways to get an advantage and that everyone can built an inverted engine with a high tank. But the original ship had none of that and not expected to be over 100 mph. If the loop holes are eliminated it will slow the ships a bit and allow some of the older fliers to keep participating with a simple setup.

Best,   DennisT

Offline bob whitney

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Re: perky
« Reply #6 on: August 06, 2021, 08:52:06 AM »
this could all be a rumor
rad racer

Online Dave Rigotti

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Re: perky
« Reply #7 on: August 06, 2021, 11:36:10 AM »
I don't know why inverted engines were permitted in the first place.  The plans show an upright engine......

BTW.... Is it permitted to make the wing thicker than shown on the plans?
Dave Rigotti
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Online Dennis Toth

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Re: perky
« Reply #8 on: August 06, 2021, 01:15:33 PM »
Another thing can you make the wing thinner than show? Seems all that is required is the general outline and dimensions.

Best,   DennisT

Online Dennis Toth

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Re: perky
« Reply #9 on: August 06, 2021, 08:17:15 PM »
These speed ships are basically a rock on the string, so only a small amount of lift is needed. This ship is bigger then most D speed ships which are considerably heavier. The question was only to get clarification on what is allowed by the rules. As I said seems we only need to build to the plan view of the ship and side view of the fuse. Is this correct?

Best,   DennisT

Offline C.T. Schaefer

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Re: perky
« Reply #10 on: August 07, 2021, 06:19:15 AM »
but I am one of the older guys :o

Online Dennis Toth

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Re: perky
« Reply #11 on: August 07, 2021, 06:39:18 AM »
I'm also one of the old guys and am looking to build a ship this year. Maybe since Paul Smith is running this event he could jump in here and clarify any changes being looked at. We are all just flapping our mouths with nothing to really back it up. Fun discussion but it is holding up building for some.

Best,   DennisT

Offline Al Ferraro

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Re: perky
« Reply #12 on: December 22, 2021, 09:03:09 PM »
I assume that by eliminating the inverted engine it would remove being able to mount the tank above the needle valve level and require true suction fuel feed rather then gravity assist there by requiring smaller venturi size.
Best,   DennisT
  Bob won Perky at Brodak 2018 using a up-rite mounted engine with a speed over 116mph.
Al

Offline BillLee

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Re: perky
« Reply #13 on: December 23, 2021, 05:59:08 AM »
,,,,, eliminate legal cheating.......
Now THAT is an oxymoron if I ever saw one!  :)

This whole question of "gravity feed" being cheating in a suction-only event begs the question: what is suction feed? I always thought that what it was NOT was pressurized fuel system ala crankcase or muffler or bladder pressure applied to the system, otherwise "suction". But then, I am just another of those "old guys", so what do I know. :P

Comments, please?!
Bill Lee
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Online Paul Smith

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Re: perky
« Reply #14 on: December 23, 2021, 10:55:40 AM »
I don't know why inverted engines were permitted in the first place.  The plans show an upright engine......

BTW.... Is it permitted to make the wing thicker than shown on the plans?

I agree you 100%. 
But I didn't write the rules, I just volunteered to continue to be the scorekeeper.
If I were to be a rules-writer I would have stuck to upright like plans show.
Paul Smith

Online Paul Smith

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Re: perky
« Reply #15 on: December 23, 2021, 10:59:03 AM »
I'm also one of the old guys and am looking to build a ship this year. Maybe since Paul Smith is running this event he could jump in here and clarify any changes being looked at. We are all just flapping our mouths with nothing to really back it up. Fun discussion but it is holding up building for some.

Best,   DennisT

I don't plan to change anything.  I undertook score-keeping with rules that were there before me. 
I think an average speed award is a bit silly.  But I kept it in and also donated a top speed prize.
Paul Smith

Offline C.T. Schaefer

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Re: perky
« Reply #16 on: December 24, 2021, 05:30:54 AM »
I think that someone is stirring  an empty pot.

Online Paul Smith

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Re: perky
« Reply #17 on: December 24, 2021, 08:32:32 AM »
I think that someone is stirring  an empty pot.

The three top winter (and Covid) sports are:

Stirring the pot
Stoking the coals, and
Adding fuel to the fire
Paul Smith

Offline Fred Cronenwett

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Re: perky
« Reply #18 on: December 24, 2021, 09:01:09 AM »
Lafayette Esquadrille awards the Average speed in Fox 35 and Perky at our contests in St Louis. For those who don't have the fastest models it's a chance to participate and maybe win the average speed award.

Feb 27 - Perky and Fox 35 will be flown
May 14-15 - Perky and Fox 35 along other speed events will be flown

Fred
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Online Bob Heywood

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Re: perky
« Reply #19 on: December 24, 2021, 09:16:12 AM »
1) Currently, Perky is the most popular active class in C/L Speed.

2) The Rule set is 16 paragraphs printed on a single page. It's the same rule set for everybody. There is enough latitude in those 16 paragraphs to make the class interesting and allow for creative development. So, the Rule set as is must be working pretty well. All that is needed are enough details to define the class and no more. READ THE RULES!

3) The very last thing that should ever happen is to change the Rule set in such a way that would harm existing participation!

4) This whole thread is based on a single, off the cuff negative comment made by an individual, who does not fly Perky, at this year's NATS. It's a case of rumor and inuendo run amok.

5) Fly low...Fly fast...
"Clockwise Forever..."

Offline Dan McEntee

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Re: perky
« Reply #20 on: December 24, 2021, 09:57:33 AM »
I think an average speed award is a bit silly.  But I kept it in and also donated a top speed prize.

     As I remember it, wasn't hitting the closest to the average speed the main objective of the contest anyway ar it's inception, and this because it was a postal event? Our club adopted the even like a lot of clubs and have kept the rules intact including the average speed but added podium places, and maybe even the slowest award. I agree with Mr. Heywood's comments. I have seen events all across the wide spectrum of model aviation die off and blow away because they couldn't leave the rules alone, and a lot of these were "entry level" contests intended to attract new blood, like the Perky even was. If you have 6 or 8 newbies who spent the winter building a model and then the spring working out the kinks and learning the drill of flying speed, and then you tell them that , even if it's two years down the line, that their model isn't allowed any longer, guess who you won't see in the entry list again??
  MERRY CHRISTMAS,
   Dan McEntee

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Online Paul Smith

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Re: perky
« Reply #21 on: December 25, 2021, 12:16:13 PM »
The downside of "average only" is that there's no incentive to even try to go fast, which is the object of speed.

So when I run an event, I give "bonus" prizes for actual speed and also the average award as per the rules.

At The AMA Nats, where I'm just a customer entry, the setup is the same.

So, if you want to just go for average, you have that option.
Paul Smith

Offline Les Akre

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Re: perky
« Reply #22 on: December 25, 2021, 02:25:18 PM »
Where can one find a copy of the Perky rules? Are diesels OK to use as well?

Les

Offline Bill Hughes

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Re: perky
« Reply #23 on: December 25, 2021, 02:29:54 PM »
They are on the NASS Web Site.   clspeed.com
Yes, Diesels are ok to use. 

Bill Hughes

Offline Dan McEntee

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Re: perky
« Reply #24 on: December 25, 2021, 04:59:55 PM »
The downside of "average only" is that there's no incentive to even try to go fast, which is the object of speed.

So when I run an event, I give "bonus" prizes for actual speed and also the average award as per the rules.

At The AMA Nats, where I'm just a customer entry, the setup is the same.

So, if you want to just go for average, you have that option.


   Basically yes, but as the top speeds increase so does the average. The average floats with speeds and entry numbers, and that takes some tuning experience and savvy., and if you fall behind the curve, then you need to pick up your speeds accordingly.  It's still something to aim for.

    MERRY CHRISTMAS!
   Dan McEntee
AMA 28784
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AMA 480405 (American Motorcyclist Association)

Online Paul Smith

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Re: perky
« Reply #25 on: December 25, 2021, 06:36:28 PM »
It all depends if you're in a one-day contest or a year-long postal event.

In a one-day thing you might actually be able to aim for the average.

In a postal you go as fast as you can and hope to be above average.

In practice, the average in the postal has improved more because slow entries quit than because he fast went faster.
Paul Smith

Offline Les Akre

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Re: perky
« Reply #26 on: December 26, 2021, 02:17:23 AM »
Thanks Bill, I'll check it out.

Les

Online Dennis Toth

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Re: perky
« Reply #27 on: December 26, 2021, 05:33:42 PM »
Les,
Attached is a rough copy of plans for the Perky.

Best,    DennisT

Offline Les Akre

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Re: perky
« Reply #28 on: December 27, 2021, 04:01:14 AM »
Thanks Dennis

Les

Online B Johanson

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Re: perky
« Reply #29 on: December 27, 2021, 10:44:08 AM »
I have a few questions on Perky’s that I hope someone can answer.
How big of a tank do I need for a Perky with a Nelson 15 and where does the tank mount.  I assume below the wing and as far inboard as possible.
What is the line spacing and pushrod offset distance on the bell crank?

Thanks,
Bill

Offline bob whitney

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Re: perky
« Reply #30 on: December 27, 2021, 04:11:22 PM »
 

  Bell crank   lead outs 1.730 lead-out to lead-out .push rod hole .250 from center.  control horn .400 from hole to elevator
 one oz tank is almost too much but gives u time to set needle.

my handle is an F2C handle and lines go between my fingers at 1.700
rad racer

Online Paul Smith

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Re: perky
« Reply #31 on: December 29, 2021, 10:02:59 AM »
You want to mount your tank as high up and as far outboard as you can.

Outboard?  That's the opposite of the theory I believe, but I'm willing to listen.
Paul Smith

Online Paul Smith

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Re: perky
« Reply #32 on: December 29, 2021, 10:06:06 AM »
Here's my tanks setup.  I like something close to a full ounce.  I've come up short with a 1/2 ounce. 

I let the tank be part of the surface of the model.  I've been
 trying the keep the fuel INBOARD, but an expert has recently recommended outboard.
« Last Edit: December 30, 2021, 01:11:13 PM by Paul Smith »
Paul Smith

Offline Jim Carter

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Re: perky
« Reply #33 on: December 30, 2021, 11:05:12 AM »
Here's my tanks setup.  I like something close to a full ounce.  I've come up short with a 1/2 ounce. 

I let the tank be part of the surface of the model.  I've bee trying the keep the fuel INBOARD, but an expert has recently recommended outboard.
Man, that's nice!  I'm impressed!

Jim

Online Dennis Toth

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Re: perky
« Reply #34 on: December 30, 2021, 11:11:29 AM »
Gees this takes rock on a string to a new level!!

Seriously, Paul very nice pan. Could you post some details and photos of the construction method/materials you used.

Happy New Year!!    DennisT

Online Paul Smith

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Re: perky
« Reply #35 on: December 30, 2021, 01:00:38 PM »
The "pan" is just the wooden bottom half of the Perky.

I built two successful Perky's this way.  Two bolts hold it together.  A 3 mm allen bolt goes through the bellcrank axle in front and a smaller 4/40 holds the tail.

Thus I can access everything inside the model with only two bolts, just like magnesium pan speed plane.

The top and bottom were laminated from 1/8" square, sanded smooth and silked.

This was my first pass at a Perky.  It lasted me about 15 years, including two minor crashes and the final big one that wiped it out. 
Paul Smith

Offline Les Akre

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Re: perky
« Reply #36 on: December 30, 2021, 09:42:27 PM »
Here's my tanks setup.  I like something close to a full ounce.  I've come up short with a 1/2 ounce. 

I let the tank be part of the surface of the model.  I've been
 trying the keep the fuel INBOARD, but an expert has recently recommended outboard.

Paul

Your pic shows at least half the width of the tank on the outboard side. That is how I set up all my models that run a suction/uniflow engine and tank system. Moving the tank outboard effectively richens up the ground setting, eliminating the lean takeoff stumble. If/when I build a perky, I'll probably build it so the tank can be adjusted inboard/outboard.

Les


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