News:


  • July 04, 2025, 08:13:37 AM

Login with username, password and session length

Author Topic: Coming soon to a contest near you! (unless you live on the west coast)  (Read 7422 times)

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
It's been under construction since the middle of last August, and now, the Trivial Pursuit is ready to fly!  We got it bench trimmed today and gave it a bench run, and the RO-Jett 76 seemed very happy with the way we're starting out at for a set up (pipe length 19.25" and 14-5 Rev Up at 8500 RPMs). Final weight after adding 5............yes 5 ounces of nose weight is 72 ounces.

It might fly tomorrow, or wednesday!

PS.  We went flying today (didn't fly the TP because the glue in the hinges is still drying) and it seems like I'm flying as good or better than I was at the end of last year!!  26 days until we leave for Muncie!!!!
Matt Colan

Offline FLOYD CARTER

  • 24 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4503
    • owner
Another 20-pointer!  (or should be). Too bad the west coast is out of reach, but you would be more than welcome here.

Floyd Carter
Eugene, OR
91 years, but still going
AMA #796  SAM #188  LSF #020

Offline Steve Fitton

  • 24 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2278
Looks awesome!  Nice job on that bird!
Steve

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
5 OZ ????? 141 Grams....  that seems like an excessive amount to get the CG right.
Esp with such a BIG engine upfront.

Is it an excessively heavy tail? - Does'nt look it.

I might have been tempted to fly it as is first and see how it balanced in flight, see how it tracked in flight and adjust weight from there.




If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
5 OZ ????? 141 Grams....  that seems like an excessive amount to get the CG right.
Esp with such a BIG engine upfront.

Is it an excessively heavy tail? - Does'nt look it.

I might have been tempted to fly it as is first and see how it balanced in flight, see how it tracked in flight and adjust weight from there.






I know, that's what's so weird.  When I built the stab and elevators, the final weight was 2.6 ounces with silkspan on it, so obviously not heavy at all. We balanced it exactly where Ted told me to balance it and that's how much weight it took to get it to where it should be.  Hopefully some will come out of the nose.

Matt Colan

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
Well I certainly would listen to what Ted says.. his design, his model, Past Nats champion an expert trimmer.


Just for me personally, perhaps I would have judged for myself based on powerplant, with fuel, prop combination ect, in flight as built before I added that amount. Have a look at how it sits, Go through the trimming process, see how the turn radii is and go from there.

Look adding its not going to kill you - conversely, CG too aft, wont cause the model to be unflyable either. Just sounds like an excessive amount.. and 2.5 oz stab isnt heavy...

Would just be a bit sensitive and not sit level for level flight tracking but without flying it you wont know.

Its certainly sound advice - get the CG right, I've never needed to add close to that amount - 1 - 1.5 oz at MAX. Sometimes jsut the difference between carbon spinner vs metal.

Good luck with it - hope to see it in person in muncie.



Edit note :

I saw that you added the noseweight to the tank floor - that could explain the extra weight - I like to add nose weight as far forward as possible. One trick taught to me years ago - was to carve out underneath the engine shaft - between the top block , and the engine shaft - or even under the crankcase. Add weight there it will push it atleast another 3 inchs further forward than under the tank.


If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Well I certainly would listen to what Ted says.. his design, his model, Past Nats champion an expert trimmer.


Just for me personally, perhaps I would have judged for myself based on powerplant, with fuel, prop combination ect, in flight as built before I added that amount. Have a look at how it sits, Go through the trimming process, see how the turn radii is and go from there.

Look adding its not going to kill you - conversely, CG too aft, wont cause the model to be unflyable either. Just sounds like an excessive amount.. and 2.5 oz stab isnt heavy...

Would just be a bit sensitive and not sit level for level flight tracking but without flying it you wont know.

Its certainly sound advice - get the CG right, I've never needed to add close to that amount - 1 - 1.5 oz at MAX. Sometimes jsut the difference between carbon spinner vs metal.

Good luck with it - hope to see it in person in muncie.


Yea, and since it's the first flight, I want to be "safe."  I don't want anything bad to happen, which is also why I put an excess amount of tip weight in the plane also, there's probably going to be half an ounce of tip weight taken out after 4 flights or so, but, like I said, I want to be safe.

Other than that, the vertical cg is just about perfect, just ever so slightly bottom heavy and the motor runs good and it's BY FAR THE BEST LOOKING PLANE I'VE EVER BUILT!

Edit: I just checked the forecast for tomorrow and it looks like it might go in the air for the first time!!!!!!!!!! #^
Matt Colan

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
Good stuff mate. She's a looker alright, good luck with your trimming Hope you do well in your 1st nats.

Seeya on the Lpad.
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

Offline Steve Fitton

  • 24 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2278
It should be reasonably safe if it ends up being nose heavy.  You might go back and recheck your measurements on the CG and make sure the measurements that you gave Ted were correct.  I'm sure Ted gave you a detailed treatise on how to determine MAC and CG, etc (I have his note to me from a few years back) pinned to the shop wall as a reference.  Just remember those calculations depend on accurate measurement going in...

I know time is short before Brodaks and the Nats, but be patient in flight testing(!)
Steve

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
It should be reasonably safe if it ends up being nose heavy.  You might go back and recheck your measurements on the CG and make sure the measurements that you gave Ted were correct.  I'm sure Ted gave you a detailed treatise on how to determine MAC and CG, etc (I have his note to me from a few years back) pinned to the shop wall as a reference.  Just remember those calculations depend on accurate measurement going in...

I know time is short before Brodaks and the Nats, but be patient in flight testing(!)

I checked the plans from the TP that was published in Stunt News, and the cg is much farther aft than what Ted told me to balance the plane at.  I checked the balance point about where it was on those plans, and the plane is now extremely nose heavy.  We're going to reset the balance point to the high point of the wing to start and go from there.

Matt Colan

Offline Steve Fitton

  • 24 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2278
Are the plans from SN different than the plans in the RSM kit?
Steve

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Are the plans from SN different than the plans in the RSM kit?

The SN plans have a slightly longer nose and show where the cg is.

And today, I flew it!

All I can say is......HOLY CRAP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

This plane flies SOOOOOOO GOOD!!!!!!!!!!!!!!!!!  We rebalanced it before we flew and took 4 of the 5 ounces of noseweight out of the plane and left the other one ounce in the nose just to be safe.

I flew a full pattern on it's 2nd flight, and the only trim adjustments I've made have been taking the nose weight out, taking 3/4 of an ounce of tip weight out, and moving the leadouts back about 1/4 of an inch.

I forgot to seal the hinge lines so we'll do that before we fly next time and the rest of that nose weight is coming out, which brings the weight all the way down to 66 ounces!!!!!!!  Also the prop needs a little less pitch (5.1 second lap times on 67.5 foot lines).  I'm waiting in the mail for a couple carbon fiber props from Kent Tysor so I'll try those out next time.

3 full patterns today on 4 flights and by the end, I was outflying how I fly with the Oriental Plus
Matt Colan

Eric Viglione

  • Guest
  • Trade Count: (0)
Atta' Boy!  #^
EricV

Offline Jose Javier Rodriguez

  • Trade Count: (0)
  • Ensign
  • **
  • Posts: 32
  • Control Line forever.
Congratulations, good job.

Offline Will Hinton

  • 25 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2804
    • www.authorwillhinton.com
Matt, having flown two TP based ships since 2001 with over a thousand flights on the oldest one I can tell you that mid 60's for weight is absolutely fine.  My first weighs 63 oz and the current one weighed 61 oz off the board with no further weight added during trim flights.  Your ship is gorgeous and you're gonna love it even more the more you fly it!
Great job!
Will
John 5:24   www.fcmodelers.com

Offline Dennis Adamisin

  • 2019 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4401
Great Job Matt.  Practice conservatively and go-for-broke in competition!
Denny Adamisin
Fort Wayne, IN

As I've grown older, I've learned that pleasing everyone is impossible, but pissing everyone off is a piece of cake!

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
HAHA told you to take out that nose weight.

Good boy :) Sounds good.

5.1 sec is ok lap time.
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
HAHA told you to take out that nose weight.

Good boy :) Sounds good.

5.1 sec is ok lap time.

Yea, I knew that didn't sound right with all that nose weight.

The plane looked gorgeous in the air and had a good amount of pull on it, but not as much as grandpa's ole P-40.

I also started keeping a flight log with this plane so I can keep track of all trim adjustments I make on it so I won't forget anything.

I can't wait to fly it again!

PS.  one complaint I have is with the motor.  When it quits, after about one minute the motor loads up so much you almost can't turn it over.  Is that normal of RO-Jetts? and what could I do to remedy that situation?
Matt Colan

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Here's a flight report of all that happened during today's 4 flights:

Flight 1:

Prior to flight one, we rebalanced the plane because it just didn't seem right to need 5 ounces of nose weight in the plane.  We took 4 ounces out and left the other ounce in just to be safe for the first flights.

 

This flight was more me just seeing what the plane was like, I did loops squares and triangles.  I could've done a full pattern but chose not to because I was still nervous (I think we all are on that first flight).  Lap times were 5.1.  I flew very soft corners and it yawed so we moved the leadouts when I landed about 1/4 inch back.

 

Flight 2:

I got a total timed run and it was 6 minutes and 33 seconds.  This flight was a full pattern except for the reverse wingover and I was really impressed with how well this plane flew already.  This time I hit the corners a little harder and noticed it was hinging.  When I landed, we took out 1/2 an ounce of tip weight.

 

Flight 3:

Full pattern!!!  With the reverse wingover this time.  I hit the corners even harder and started working on getting my shapes and bottoms down and it came very easily.  It still hinged just a little bit, so I took another 1/4 ounce of tip weight out.

 

Flight 4:

Another full pattern, and I brought everything down to 45 degrees and flew the plane as best I could after only 4 flights.  Now I noticed it wasn't easy to get it through a hard corner, so when we go flying again.  That last ounce of nose weight I left in is coming out, and, since I forgot to when we bench trimmed it, seal the hinge lines.  After that, I might open up the handle another 1/4 inch to make the line spacing 4 1/4 inches, but I first want to see what those trim adjustments will do.
Matt Colan

Offline Doug Moon

  • 25 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2311
Yea, I knew that didn't sound right with all that nose weight.

The plane looked gorgeous in the air and had a good amount of pull on it, but not as much as grandpa's ole P-40.

I also started keeping a flight log with this plane so I can keep track of all trim adjustments I make on it so I won't forget anything.

I can't wait to fly it again!

PS.  one complaint I have is with the motor.  When it quits, after about one minute the motor loads up so much you almost can't turn it over.  Is that normal of RO-Jetts? and what could I do to remedy that situation?

Matt,

Sounds great, and it looks great too!!

66oz is right in the wheel house for that plane.

About the motor locking up.  The liner is cooling off and the pinch at the top is grabbing the hot expanded piston.  Our GMA Jett 50 did that very same thing.  The fastest way to get rid of that issue is some more bench running.  Only this time cycle it on and off and it get it hot.  Dont hurt it or overheat it but run it up some and make it work and your pinch issue will be gone.  Or a hard lean run in the air will do it too.  Otherwise you will be waiting around after each flight for it to cool completely before you roll it over.  With it pinching like that it can be dangerous if you flip by hand as a carbon prop will cut through most anything you had on.  And it can break your props if you are flipping with a stick.  Or break the plane if you flip it and it locks and lose your grip and damage the model. More bench time will get that out of there asap.

Keep us posted.
Doug Moon
AMA 496454
Dougmoon12@yahoo.com

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Matt,

Sounds great, and it looks great too!!

66oz is right in the wheel house for that plane.

About the motor locking up.  The liner is cooling off and the pinch at the top is grabbing the hot expanded piston.  Our GMA Jett 50 did that very same thing.  The fastest way to get rid of that issue is some more bench running.  Only this time cycle it on and off and it get it hot.  Dont hurt it or overheat it but run it up some and make it work and your pinch issue will be gone.  Or a hard lean run in the air will do it too.  Otherwise you will be waiting around after each flight for it to cool completely before you roll it over.  With it pinching like that it can be dangerous if you flip by hand as a carbon prop will cut through most anything you had on.  And it can break your props if you are flipping with a stick.  Or break the plane if you flip it and it locks and lose your grip and damage the model. More bench time will get that out of there asap.

Keep us posted.

The engine I have is WELL broken in.  I got it from Rich Walbridge who got it from Windy, and Windy put 5 gallons of fuel through it, and Rich put about 2 if I remember right.  Is that still the reason?
Matt Colan

Offline Randy Ryan

  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1766
Looks OUTSTANDING Matt!!
Randy Ryan <><
AMA 8500
SAM 36 BO all my own M's

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
You didnt have 5 oz of wingtip weight also did you ?  ;D
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

ChrisSarnowski

  • Guest
  • Trade Count: (0)
Hi Matt,

Your new ship looks really great!! I'm glad you like it so much!!

-Chris

Eric Viglione

  • Guest
  • Trade Count: (0)
Matt  - I ran a 76 for a little while, and I know what you mean. BE CAREFUL! Any high performance engine can bite you, especially when they have high compression. (mine measured over 160PSI on my compression gage!)
I would avoid flipping ANY ABC/ABN motor unnecessarily other than to start it (EDIT : And even starting it, I back flip, I never pulled it through a compression stroke) because one, I think it can cause unintended wear because the sleeve isn't expanded like when it's running, and two, it might "fire" up on you. (ouch)

Like Brett observed on his 65, I also noticed on the 76 that they tend to not like to be varnished up...not even a little, and need a tank of straight synthetic run through them now and then. This seems to be more noticable in engines with more taper in the sleeve and that "pinch" at the top doesn't allow for any varnish build up without getting what you noticed as a side effect. I think this my be your problem more than anything else.

When I got mine used, someone had run it so hard I had to disassemble and clean it by hand. The head chamber and top of the piston were pitch black and the sleeve was gold with varnish. I'm sure yours isn't that bad, just try a tank or two of synthetic. It's not a big deal really, and should be part of your regular maintenance program with that engine. Also, I would suggest running a low castor content fuel like Sig Synth or Powermaster's special 18% oil fuel. That engine won't run Sig Champion or Powermaster GMA blend for very long without varnishing up, or at least mine wouldn't.

It's been more than a few years since I ran one, and someone else may have more current info to post, but I'm pretty confident this is what you are seeing.

Great job!
EricV

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Matt  - I ran a 76 for a little while, and I know what you mean. BE CAREFUL! Any high performance engine can bite you, especially when they have high compression. (mine measured over 160PSI on my compression gage!)
I would avoid flipping ANY ABC/ABN motor unnecessarily other than to start it (EDIT : And even starting it, I back flip, I never pulled it through a compression stroke) because one, I think it can cause unintended wear because the sleeve isn't expanded like when it's running, and two, it might "fire" up on you. (ouch)

Like Brett observed on his 65, I also noticed on the 76 that they tend to not like to be varnished up...not even a little, and need a tank of straight synthetic run through them now and then. This seems to be more noticable in engines with more taper in the sleeve and that "pinch" at the top doesn't allow for any varnish build up without getting what you noticed as a side effect. I think this my be your problem more than anything else.

When I got mine used, someone had run it so hard I had to disassemble and clean it by hand. The head chamber and top of the piston were pitch black and the sleeve was gold with varnish. I'm sure yours isn't that bad, just try a tank or two of synthetic. It's not a big deal really, and should be part of your regular maintenance program with that engine. Also, I would suggest running a low castor content fuel like Sig Synth or Powermaster's special 18% oil fuel. That engine won't run Sig Champion or Powermaster GMA blend for very long without varnishing up, or at least mine wouldn't.

It's been more than a few years since I ran one, and someone else may have more current info to post, but I'm pretty confident this is what you are seeing.

Great job!
EricV

The fuel I'm running is Powermaster RO-Jett fuel, 10-18 I think?  This fuel has all synthetic in it from what I've heard.  It was fairly warm yesterday when I flew it and I didn't want to flip it except to start it.  I gave it 3 chokes, and then put the battery on and started it once I got the motor to turn over.

The way we got the motor to turn over has holding it nose up and spinning the prop back and forth to try and get, what we thought was oil out of the cylinder.  Eventually we were able to get it to turn over, but it took a couple minutes.
Matt Colan

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
You didnt have 5 oz of wingtip weight also did you ?  ;D

Nope, I started with 2 ounces, and I'm down to 1 1/4 now.  ;D
Matt Colan

Eric Viglione

  • Guest
  • Trade Count: (0)
Ah... OK, good. It might still be varnished a little, just keep running that fuel and see if it improves over time...and you are probably right, oil/fuel will run forward in handling. I used to transport my planes nose down in a rack... not any more since I started running pipes. Keep the nose up even when handling the plane at the field. When you land and the oils are still hot and runny, you can drain the pipe easier, hold the nose up and rock the plane around a little to clear the baffle when carrying the plane back to the flight line.

If your lap times are good upright and inverted, and your manuever speeds are symetrical, your tank shim should be ok, but I've still seen them syphon when sitting on the ground depending on routing of your fuel tubing, and /or landing gear attitude...(I've had to bend the tail wire or go to bigger wheels to enhance the stance once or twice) When flying my PA's on a hot day I don't even choke them between flights, just back flip and fly, as the act of filling the tank seems to move enough fuel forward to be "ready" to start.

Sounds like you have a pretty good handle on it already. Keep up the good work.
EricV

Offline Steve Fitton

  • 24 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2278
RO-Jett blend fuel is 23% all synthetic, I believe, and its good stuff.  I'd still run it but I can't get any, unless Bob Krug brings his truck to the Nats this year...

I've launched Tysor's 76 powered Strega a number of times, and his 76 can get tight in a hurry as well.  Just be super careful pulling that prop through until you are sure the cylinder is clear, especially when you get one of Kent's props on it...

Erics trick of walking it off the circle nose up, especially on the last flight of the day, is a good one.  I've watched a suprising amount of oil drain out of the pipe if you remember to do it when its still hot.  Trouble is I seldom remember(!)
Steve

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
RO-Jett blend fuel is 23% all synthetic, I believe, and its good stuff.  I'd still run it but I can't get any, unless Bob Krug brings his truck to the Nats this year...

I've launched Tysor's 76 powered Strega a number of times, and his 76 can get tight in a hurry as well.  Just be super careful pulling that prop through until you are sure the cylinder is clear, especially when you get one of Kent's props on it...

Erics trick of walking it off the circle nose up, especially on the last flight of the day, is a good one.  I've watched a suprising amount of oil drain out of the pipe if you remember to do it when its still hot.  Trouble is I seldom remember(!)

I am careful, and once i do get one of those props, I'll be even more careful about how I handle the prop.  And thanks for the advice, I'll try that next time I go out to fly it  H^^
Matt Colan

Offline Doug Moon

  • 25 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2311
If you are certain it is well broken in, and it sounds like it is, stay with the all synthetic.  Varnish is your biggest enemy with that motor.  You never know what was run through it before so stick with that.

It also sounds like you might be filling the cylinder as you fill it.  Or there is enough flow through as you fill and the head locks up or tries to with the first roll over.  One way to check it is to pull the plug after a flight and you will see it is probably dry, or pretty dry.  Then go through your regular filling motion and immediately pull the plug and check it.  Look for it to be full and some dripping from the cylinder.  Or start flipping it as normal and if it starts to get hard to pull through like normal try turning the plane over and see if it gets easier to pull it through the compression stroke.  Not flipping but just pulling it through. It will still be hard but it will ease up some in the upright position. 

I had this issue with a setup a few years ago and I found a relatively simple fix for that setup.  First off I would never fill the plane until it was sitting on the tarmac and ready to fly.  Filling early only made the problem worse.  Once I was ready to fill I would make sure the prop was turned so the piston was on the start of the compression stroke.  This closes the intake port on the crank and the cylinder.  Then after filling I would choke twice attach the battery and start flipping.  If it was hot then no choking, just start flipping.

It is so important to have a starting routine.  One for regular cold/warm starts and one for hot starts.  Hot starts are tricky.  If you choke it even once you can "flood" it and it will never start.  I have heard that it isnt actually flooding it is cooling the piston and it shrinks and loses its seal. Once the whole thing cools it starts fine.

My PA is six chokes, 3 flips, attach the battery, twist the spinner backwards and it goes.  Hot starts, fill the tank to the desired level, no chokes, flip backwards by lightly bouncing the prop backwards with a chicken stick/heater hose. 

Keep us posted.
Doug Moon
AMA 496454
Dougmoon12@yahoo.com

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
If you are certain it is well broken in, and it sounds like it is, stay with the all synthetic.  Varnish is your biggest enemy with that motor.  You never know what was run through it before so stick with that.

It also sounds like you might be filling the cylinder as you fill it.  Or there is enough flow through as you fill and the head locks up or tries to with the first roll over.  One way to check it is to pull the plug after a flight and you will see it is probably dry, or pretty dry.  Then go through your regular filling motion and immediately pull the plug and check it.  Look for it to be full and some dripping from the cylinder.  Or start flipping it as normal and if it starts to get hard to pull through like normal try turning the plane over and see if it gets easier to pull it through the compression stroke.  Not flipping but just pulling it through. It will still be hard but it will ease up some in the upright position. 

I had this issue with a setup a few years ago and I found a relatively simple fix for that setup.  First off I would never fill the plane until it was sitting on the tarmac and ready to fly.  Filling early only made the problem worse.  Once I was ready to fill I would make sure the prop was turned so the piston was on the start of the compression stroke.  This closes the intake port on the crank and the cylinder.  Then after filling I would choke twice attach the battery and start flipping.  If it was hot then no choking, just start flipping.

It is so important to have a starting routine.  One for regular cold/warm starts and one for hot starts.  Hot starts are tricky.  If you choke it even once you can "flood" it and it will never start.  I have heard that it isnt actually flooding it is cooling the piston and it shrinks and loses its seal. Once the whole thing cools it starts fine.

My PA is six chokes, 3 flips, attach the battery, twist the spinner backwards and it goes.  Hot starts, fill the tank to the desired level, no chokes, flip backwards by lightly bouncing the prop backwards with a chicken stick/heater hose. 

Keep us posted.

Hi Doug,

What I was doing with the TP for starting two days ago was, choke it 3 times, turn it over a few times, and then put the battery on and start it.  I checked this morning and the plane has been nose down since I stopped flying that day, and it turns over free as can be.  Maybe whatever it was worked it's way out?

I'll let you all know next time I fly it. H^^
Matt Colan

Offline john e. holliday

  • 25 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 22989
Matt, young man,  the plane is absolutely gorgeous and you are way beyond your years.  I know from past posts that Grandpa has been a big influence on you as you are on him.   But, I can tell that you listen very well.  Don't push the plane too hard until you need to.  Now plan on having fun at the NATS.  H^^
John E. "DOC" Holliday
10421 West 56th Terrace
Shawnee, KANSAS  66203
AMA 23530  Have fun as I have and I am still breaking a record.

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
yeah - wait till your at the Nats then push it :)
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
We got ourselves a PERFECT day to fly stunt!  Blue skies, light breeze and very pleasant temperatures!  I'll be flying the TP today after I get back from baseball practice today.
Matt Colan

Offline Bill Little

  • 2017
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 12668
  • Second in COMMAND
Hi Matt,

Best of luck with the Trivial Pursuit!  It really turned out gorgeous.  Hopefully I will make it to Muncie for a couple days and we will get to meet.  Best wishes!

Big Bear
Big Bear <><

Aberdeen, NC

James Hylton Motorsports/NASCAR/ARCA

AMA 95351 (got one of my old numbers back! ;D )

Trying to get by

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Thanks Bill!

Today I got 2 more flights in the plane.  This time, instead of stunt heaven like it was earlier today, the wind kicked up to a pretty stiff breeze.

I sealed the hinge lines before I flew, and then I flew my flight.  The first flight went without a problem.  The 2nd flight, the wind was blowing a little bit more, and grandpa told me I should richen the motor up very slightly, and those two things caused me to get blown out of the hourglass.  Also a piloting error helped the cause out a lot because I overturned the first corner and the wind took it and it floated around inverted for a lap before I got line tension back and brought it back around and flew the rest of the tank out.

Today I also noticed that the nose weight still probably has to come out because it was getting a little difficult to get the last turn of the triangle right.

Things will definitely be sorted out by the time we leave for Muncie!

Oh, and whatever was causing the motor to lock up when it quit, it went completely away as I was able to turn the motor over when it quit and after about 5 minutes sitting on the ground.
Matt Colan

Offline Dick Pacini

  • 25 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1650
Matt, you said previously that it yawed, so you moved the leadouts 1/4" back.  To correct yaw, you move them forward a little at a time.
AMA 62221

Once, twice, three times a lady.  Four times and she does it for a living.  "You want me on that wall.  You need me on that wall."

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
Matt, you said previously that it yawed, so you moved the leadouts 1/4" back.  To correct yaw, you move them forward a little at a time.

Thanks for correcting me Dick!

I thought about it one night and that was someting else I didn't think was right, I'll mention it next time we fly.
Matt Colan

Offline PJ Rowland

  • AUS - 29541 AMA - 809970
  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2056
  • Melbourne - AUSTRALIA
" Today I also noticed that the nose weight still probably has to come out "

;D
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

...
 I Yearn for a world where chickens can cross the road without having their motives questioned.

Offline Howard Rush

  • 25 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 7980
A yaw oscillation?  It might depend on whether they're too far forward or too far back.  Once the CG gets to 7" forward of the crack, I'd move the leadouts to Dave Fitz's recommended position and adjust them from there. 

What is your rudder position? 
The Jive Combat Team
Making combat and stunt great again

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
What is your rudder position? 

I got no rudder offset
Matt Colan

Offline Derek Barry

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 2835
Thanks Bill!

Today I got 2 more flights in the plane.  This time, instead of stunt heaven like it was earlier today, the wind kicked up to a pretty stiff breeze.

I sealed the hinge lines before I flew, and then I flew my flight.  The first flight went without a problem.  The 2nd flight, the wind was blowing a little bit more, and grandpa told me I should richen the motor up very slightly, and those two things caused me to get blown out of the hourglass.  Also a piloting error helped the cause out a lot because I overturned the first corner and the wind took it and it floated around inverted for a lap before I got line tension back and brought it back around and flew the rest of the tank out.

Today I also noticed that the nose weight still probably has to come out because it was getting a little difficult to get the last turn of the triangle right.

Things will definitely be sorted out by the time we leave for Muncie!

Oh, and whatever was causing the motor to lock up when it quit, it went completely away as I was able to turn the motor over when it quit and after about 5 minutes sitting on the ground.

By the sounds of it, you need to add tip-weight. A direct result of adding tip-weight is the need to move the leadouts forward, assuming that everything is pretty close to begin with. If I were you I would just put in a little more tip weight and fly it again. This should give you more overhead tension. IF it develops more yaw then I would say move the leadouts forward a little bit at a time until it goes away. Going with Dave's recommendations should get you in the ballpark and the tip-weight/leadout balancing act can begin. Get rid of that nose-weight and open the handle up for more turn authority.

Derek

Online Matt Colan

  • N-756355
  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3529
By the sounds of it, you need to add tip-weight. A direct result of adding tip-weight is the need to move the leadouts forward, assuming that everything is pretty close to begin with. If I were you I would just put in a little more tip weight and fly it again. This should give you more overhead tension. IF it develops more yaw then I would say move the leadouts forward a little bit at a time until it goes away. Going with Dave's recommendations should get you in the ballpark and the tip-weight/leadout balancing act can begin. Get rid of that nose-weight and open the handle up for more turn authority.

Derek

That's the plan.  Dave gave me his numbers and he has 1/4 ounce more tip weight in his Star Gazer IV than I have in mine.  It was hinging with 1 1/2 ounces of tip weight on the triangle, at least I'm darn sure it was.

Matt Colan

Tags: