Author Topic: Perky Questions (Read 1598 times)

Alan Hahn · « **on:** October 24, 2007, 01:51:17 PM »

I've got the skeleton of my BlackHawk Perky fuse laid out, and I am trying to figure out where people put the darn fuel tank on this thing. I plan to use the Fox15BB engine, and I figure it only has to run for a minute and a half (30 seconds to get out to the handle, and ~ 1 minute of flying if I go 60mph). So it doesn't take much fuel I think, but still there isn't much room. It sounds like people are putting a tank in past the firewall (from comments about putting the bellcrank in the wing to make space for a tank), but even that is pretty tight.
I am guessing I will be bending and soldering my own tank,--- is that the way people are going?
I could wait until the next Tree Town meeting and ask Billy Hughes or maybe Glenn Lee if they comes that meeting, but that's 2 weeks away!
Thanks, Alan

Tom Weedon · « **Reply #1 on:** October 24, 2007, 03:21:49 PM »

I've got another Perky question. Is it legal to use a Schnuerle engine for the Perky Postal Races? I'm thinking of a Fox 15, BB with Schnuerle porting.

Tom Weedon

Paul Smith · « **Reply #2 on:** October 24, 2007, 03:27:47 PM »

As far as I can see, any engine goes, within the displacement and suction venturi requirments.

---------------------------------

Fitting in the fuel tank is part to the challenge. Think how hard it would be with points, a battery, and a condenser.

Thomas Wilk · « **Reply #3 on:** October 24, 2007, 07:21:42 PM »

i have a Bantan .19 ignition for mine. i'll let you know if i can shoehorn it all in.

Tom Wilk

LARRY RICE · « **Reply #4 on:** October 24, 2007, 10:54:32 PM »

A small fuel tank can be fitted in place of the coil as the feed line does not need to line up with the venture since you will not be stunting. Another option is to cut out the bulkhead and fit the tank between the engine and bellcrank. I wanted to move the bulkhead forward to provide more room but was out voted.
Larry

john e. holliday · « **Reply #5 on:** October 25, 2007, 09:06:57 AM »

A lot of people don't realize that tank location does make a difference as far as needle setting when the plane gets air borne. Have fun, DOC Holliday

Alan Hahn · « **Reply #6 on:** October 25, 2007, 11:18:18 AM »

Doc,
Yes I have thought of that. You want the needle spot on for good speed, but not cooking the engine on the ground and vice versa-- or so rich it doesn't want to accelerate. Also since speed is from a dead stop to 16 laps, it adds to the equation.

This may be a really stupid question, but I've never done a speed event,---is the pilot suppose to start the engine, or is he out at the handle and having a pit man starting the engine (would save some seconds in my total time calculation above).

Paul Smith · « **Reply #7 on:** October 25, 2007, 12:50:11 PM »

It only takes 35-to-42 seconds to do the timed run, so an extra 20 or so to get out the handle shouldn't be problem. I've done it both ways. It all depends if you have someone as good as youself or better to start & adjust the engine.

Thus far, my best time has been on flight where the engine sagged a little on the first quarter lap, then ran strong the rest of the way. Obviously, it would be best to be perfect all the time.

Alan Hahn · « **Reply #8 on:** October 25, 2007, 03:13:07 PM »

A note to my stooge/pit man Fred---how do you answer Paul's question!!

Thomas Wilk · « **Reply #9 on:** October 25, 2007, 03:43:54 PM »

I got this email from Frank Carlisle

http://forum.amadistrictvii.org/

We have a control line forum that was opened recently ( about 4 weeks ago) at the AMA district 7 web site.
The link above will take you there.
We have a Perky construction and engine thread going that you may be interested in.
The link above will take you to the main page. Scroll down to the c/l section. The Perky discussion can be found in the building section.
The forum is open to everyone. Please come visit.
If you would like to join in on the conversation - registration is open to all.

I'll check it daily and will try to answer the easy questions.

Tom Wilk
Old magazine Plans on CDs

Bill Gruby · « **Reply #10 on:** October 26, 2007, 08:10:06 PM »

Tom;

I went to the link and found a lot of info on the "Perky". They talked briefly about putting the Bell Crank in the wing. I understand where it goes in the wing and how to install it, but what about the line spacing. If you put it where it is comming out of the fuse., the front line will come out in the wingtip and the rear linewill come out 2 inches farther back. Is this acceptable or should the rear line be moved forward?

The engine of choice for me will be an OS .15 FP.

"Billy G"

Thomas Wilk · « **Reply #11 on:** October 26, 2007, 08:36:02 PM »

on my present Perky - the front lead out is about 1/2" back at the tip. the back lead out is about 1'2" back ot the front. i an using stranded lead outs. if you are using solid wire have them spaced anout 1/4" to 1/2" apart to keep tyhe lines fron snagging.

Tom Wilk

Bill Gruby · « **Reply #12 on:** October 27, 2007, 01:51:15 AM »

Thank you Tom:

I find what you and the others have said about the "Perky" very informative. this is my first attempt at any type of "Speed" oriented model. It seemed like an easy way to break into it. I like the idea that you don't have to be the fastest, but closest to the overall average speed to win. It kind of levels the playing field. LOL

As far as the leadouts go I pretty much thought that was the case, but wasn't sure if maybe because it is a "Speed Ship" there was a different formula to go by. Thank you again for your prompt answer.

Has anyone come up with a tank for the "Perky" yet? I am leaning toward a fabricated one to fit between the angled part of the motor mounts to about 2" long and 1/2 to 3/4 inches thick. This is fun, kinda like the old days when you had to think your way thru a model.

"Billy G"

Paul Smith · « **Reply #13 on:** October 27, 2007, 07:03:42 AM »

I just ran the leadouts outdoors, under the wing.

A plywood plate with several holes serves as a leadout adjuster.

LARRY RICE · « **Reply #14 on:** October 28, 2007, 05:33:08 PM »

Re: Perky Questions
« Reply #9 on: October 25, 2007, 03:43:54 PM » Quote

--------------------------------------------------------------------------------
I got this email from Frank Carlisle

http://forum.amadistrictvii.org/

Do you want to know how to build a Perky? Go to the above site they are building one step by step.

Bill Gruby · « **Reply #15 on:** October 28, 2007, 08:11:45 PM »

I registered today and the craftsmanship of the builder is out of this world. This will be a good build to follow even if you do not plan to build a "Perky"

"Billy G"

Alan Hahn · « **Reply #16 on:** October 29, 2007, 07:02:35 AM »

Because Fred is too modest, I need to reply---yes he is good! I'll stand out by the handle.
I am guessing the tank can be quite small. Also the shape needs to be such that if you need to short tank, the pickup needs to be in the fuel (I am assuming I'll still big it larger than I need to just to be sure and make the required number of laps. Would hate to be a lap short!

Bill Hughes · « **Reply #17 on:** November 01, 2007, 01:49:52 AM »

Alan,
Both my Models use a 28cc uniflow tank, which is plenty of fuel if your model is running well. If it is one that runs only about 60 mph (proto time) you may run short. Remeber, the slower you go the more fuel you will need. My models run between 80-95 mph (proto time) ~around 40 seconds.
Bill Hughes

Alan Hahn · « **Reply #18 on:** November 01, 2007, 10:15:24 AM »

Bill,
Yea I am guessing that having to tow the plane around on the last lap would tend to kill your speed! I guess I'll go for about an ounce---or close to your 28cc.

Author Topic: Perky Questions (Read 1598 times)

Alan Hahn

Alan Hahn

Alan Hahn

Alan Hahn

Alan Hahn