Author Topic: Shoestring Goodyear tip weight (Read 2825 times)

Mike Callas · « **on:** November 20, 2011, 11:22:20 PM »

So my first goodyear, a porky buster named Tree hugger, is being retired.

My new Shoestring is now painted. The airframe weighs in 11oz. My target total is 22oz.
I was planning on 3/4oz for tip weight. Is that enough?

Les Akre · « **Reply #1 on:** November 21, 2011, 01:44:25 PM »

Hi Mike

I heard you had to get a ladder to get the Buster down, that must have been fun!

For a SCAR Goodyear 3/4oz. should be more than enough. However, as with all racing models you still have to be leading the model and pulling back a bit on takeoff.

BTW, I sent out the tank today, you should see it in about a week. You'll have to add mount tabs, or strap it to the model, or whatever your favorite method is. If you're mounting your Brodak .25 directly to the engine bearers (ie. no engine mount plate or pads) then the tank shouldn't need a spacer. Half of the tanks width should be outboard of the needle valve. If you add an engine mount plate, or pads later on, then space the tank out equal to the width of the mount or pads.

Cheers, Les

Mike Callas · « **Reply #2 on:** November 21, 2011, 08:12:13 PM »

Quote from: Les Akre on November 21, 2011, 01:44:25 PM

Hi Mike

I heard you had to get a ladder to get the Buster down, that must have been fun!

Les,
That's a grossly exaggerated depiction of what really happened. I merely jumped on my pickup with a 15' pole to snag the Buster.

Thanks for the tank. I hope to fly SSR and Mouse 1 at the next Scar race (Provided the arbor day society does not get an injunction preventing me from flying within 1000' from any tree).

Mike

Dave Hull · « **Reply #3 on:** December 02, 2011, 07:48:54 PM »

Did he tell you that he drives a monster truck?

McSlow

Mike Callas · « **Reply #4 on:** December 02, 2011, 09:22:42 PM »

Quote from: Dave Hull on December 02, 2011, 07:48:54 PM

Did he tell you that he drives a monster truck?

McSlow

Very funny,
BTW,did I mention Dave runs the 40yd in 4 flat?
At least when theres a Cox 15 behind him for motivation!

Mike

Les Akre · « **Reply #5 on:** December 04, 2011, 04:35:41 PM »

Mike

"BTW,did I mention Dave runs the 40yd in 4 flat?
At least when theres a Cox 15 behind him for motivation!"

And his eyes get really big too.

Have you received the tank yet?

Les

Mike Callas · « **Reply #6 on:** December 04, 2011, 06:26:15 PM »

Quote from: Les Akre on December 04, 2011, 04:35:41 PM

Mike

"BTW,did I mention Dave runs the 40yd in 4 flat?
At least when theres a Cox 15 behind him for motivation!"

And his eyes get really big too.

Have you received the tank yet?

Les

Yep. Beautiful tank Les.
I ran the Brodak on the SSR today at the T4T race. Charlie drove and I pitted. I ran it rich and we got 29 laps out of it.
The plane was slow at 26sec 7 lap interval. Probably needs more time.
Only problem is....the tank soo nice I'd like another for the Goodyear!
Man, that Kusick clan is fast with their mouse racers.

Thanks again for the tank Les.

Mike

Les Akre · « **Reply #7 on:** December 04, 2011, 10:51:42 PM »

Hey Mike

The slowness can be cured, just need a bigger venturi Dia. and you'll get more laps when you get mean on the needle. I can build you a tank for the Goodyear if you need. Can you show me a pic of the engine side fuse ahead of the wing?

I saw some of the Mouse 1 results, the Kusic's heat time is good enough to be competitive at the Nat's.

Cheers, Les

Dave Hull · « **Reply #8 on:** December 06, 2011, 02:22:41 PM »

Yeah, Mouse-Mike had me practicing the 40 yd dash Sunday, too. Engine died and whippage was under-spec. Pitted that mouser on the far side. Seems appropriate for Mouse---pitting on "The Far Side"

McSlow

Mike Callas · « **Reply #9 on:** December 08, 2011, 11:03:34 PM »

Quote from: Les Akre on December 04, 2011, 10:51:42 PM

Hey Mike

The slowness can be cured, just need a bigger venturi Dia. and you'll get more laps when you get mean on the needle. I can build you a tank for the Goodyear if you need. Can you show me a pic of the engine side fuse ahead of the wing?

I saw some of the Mouse 1 results, the Kusic's heat time is good enough to be competitive at the Nat's.

Cheers, Les

Les,
There is 3" from the shutoff to the wing LE

Mike

john e. holliday · « **Reply #10 on:** December 09, 2011, 09:56:03 AM »

Did anybody really answer the question? Ihave been back thru the posts and missed it if they did. I learned a long time ago that wing tip weight is good for racing planes. Especially if you have to use people for pilots that are not that experienced. Makes take off so much easier, especially for the novices. It also helps in windy weather. On my AMA Scale Racers I used at least 3/4 ounce of lead in the outboard wing tip. On slow rat and big Shoestring racers I used a full ounce of lead. Even when I had a dedicated pilot like I did for F2C I still used some wing tip weight. There were times that a pit stop went faster than normal and the weight kept the plane on the end of the line.

Chris McMillin · « **Reply #11 on:** February 14, 2012, 03:06:38 AM »

I think he said 3/4 of and oz.

I didn't know they still run Mouse at the Nats. I thought I read Paul Gebault saying it was over, not enough entrants.
Chris...

BillLee · « **Reply #12 on:** February 14, 2012, 05:02:48 AM »

Probably best to check out the NATs schedule rather than depending on old pharts with phailing memory like Paul.

AMA Official Events

Monday, July 16
301 1⁄2 A Speed (JS)(O)
305 1⁄2 A Profile Proto (JS)(O)
318 F2C TR (O)
331 F2D (JSO)

Tuesday, July 17
307 21 Sport Speed (JS)(O)
310 F2A Speed (JSO)
312 Slow Rat Race (JSO)
321 Profile Carrier (JSO)

Wednesday, July 18
306 21 Proto Speed (JSO)
308 Formula 40 Speed (S)(O)
317 Scale Race (JSO)
319 Carrier I (JSO)
320 Carrier II (JSO)
322 Precision Aerobatics (O)** Qualifying day 1
325 Advanced Aerobatics (JSO)** Qualifying day 1
328 Combat (JSO) w/ F2D equipment & 2010 rules

Thursday, July 19
302 A Speed (JS)(O)
303 B Speed (JS)(O)
311 Rat Race (JSO)
322 Precision Aerobatics (O)** Qualifying day 2
325 Advanced Aerobatics (JSO)** Qualifying day 2

Friday, July 20
304 D Speed (SO)
309 Jet Speed (SO)
313 1⁄2 A Mouse I
322 Precision Aerobatics (O)** Semi-Finals
325 Advanced Aerobatics (JSO)** Finals
330 1/2A Combat (JSO)

Saturday, July 21
328 Combat A (JSO)
322 Precision Aerobatics (J)(S)(O)** Finals
Walker Cup Flyoff

Chris McMillin · « **Reply #13 on:** February 17, 2012, 08:14:46 PM »

Thanks!
Chris...

Mike Greb · « **Reply #14 on:** May 02, 2012, 08:07:28 PM »

I think my tipweight for Goodyears has been 4 pennies

Mike Lauerman · « **Reply #15 on:** July 17, 2012, 12:13:48 PM »

I used 4 pennies on a Goodyear Cosmic Wind, but used a nickel on my Shoestring...

BillLee · « **Reply #16 on:** September 24, 2012, 03:21:04 PM »

Quote from: Motorman on September 24, 2012, 01:17:14 PM

In 1970 we made a magnesium tip weight for FAI team race to reduce the planes overall weight, very high tech thinking.

MM

Somehow I can't see where 1/4ounce tip weight made from magnesium would weigh less than a 1/4 oz tip weight made of lead.

john e. holliday · « **Reply #17 on:** September 25, 2012, 08:45:42 AM »

Geesh -- It is like my Dad asking me, "Which weighs more a ton of dry sand or a ton of wet sand"? When I was building racing planes I always put wing tip weight in to help the pilot out that did not get enough practice. Even F2C planes had tip weight. Maybe that is why I was so slow.

Jim Holland · « **Reply #18 on:** September 25, 2012, 08:49:35 PM »

Speaking as someone who has flown a lot of control line racers, I believe its fare to say tip weight is necessary in the vast majority of cases.
I've always believed in letting people who disagree with that statement fly there own airplanes. It pretty much guarantees a dnf.

One quarter ounce tip weight is a good starting point for most .15 sized racers.

Jim Holland

P.S. I am pleased to say I agree with Mr. Lee's observations. It is a royal pain in the rear to make enough room in the wing for a quarter ounce of magnesium when a quarter ounce of lead arguably does at least as good a job.

bill bischoff · « **Reply #19 on:** September 25, 2012, 09:26:01 PM »

To be truly hi-tech, use uranium for tip weight. A little dab'll do ya'. Good luck getting your model box through the airport.

don Burke · « **Reply #20 on:** September 25, 2012, 11:37:45 PM »

Isn't lead just depleted uranium?