RE: GP Super Stearman
 

have you guys tried putting some toe-in on the wheels to compensate?

i'm on a final decision for this bird and it has to do with the spinner of which i guess i'm just going to have to buy to try.........( 2.75" AT-6 TruTurn)
the stock spinner looks great, but when place on the lathe, it's specs fall apart quickly...........i have 3 of these things and all three have over .005" runout just on the backplate alone. at the front part of the cone where it goes from straight to curve, it is out .007"...and to top it off, the cone is not a snug fit into the backplate which increase this offset even further...........probably won't see it at engine speeds, but nevertheless it's there.
all three show to be heavy on one side by quite a bit. the other thing that bothers me is the knurling on the back of the backplate which sits on the 1.60's driver washer........it doesn't use the whole area of the engines drivewasher by about 60%, and doesn't sit square.

i just received a 2.5" TruTurn to use on my Skybolt and the spinner is perfectly balanced right out of the bag.............no runout at all. backplate is flat.

seeing this quality has me believing that the GP kit spinner is good for nothing more than static display.

i wish that TruTurn made a 2.5" AT-6 spinner as the plane looks good with this size.................those of you i spoke to about the 2.75" AT-6 TT have helped me out and i thank you..........wish there were more pictures of this combo to see, but i will try and buy to see.

one thing more, i'd machine off the kit backplate to get rid of the knurling, but the thickness of this plate is already borderline for thicknes.

RE: GP Super Stearman
 

Summerwind:

Didn't need the toe in ... just more aggressive throttle at the start and she takes off great.

I agree that the supplied spinner isn't the greatest precision, but it does look good and fits my APC 16x8 with no alterations required.
So far I haven't had any problems. I wouldn't want to turn it at 25,000 rpm but it works with the Saito 150 just fine.

Ed

RE: GP Super Stearman
 

Ed,

i was pretty much set on the kit spinner until i started really checking things out, especially since it looks so scale for this bird.
none of the 3 backplates i have will sit square (flat to the drive washer)......all are touching the DW face on one side, but you see light on the opposing side, thus inducing a wobble, which since these cones already have an out of round consistency, induce even more of a wobble...............this of course is on the FT 1.60 twin which has a bigger DW than a 1.20 (not sure about the Saito's). so it may be fine on the smaller driveplated engines.
but like you said, at the below 9K rpm's we are running, it isn't that critical, or is it?.................my bugga-boo with these is that i'm an old Free Flighter who use to run engines in the 23-26,000 rpm range during competition, and any amount of out of round or wobble in a spinner could eventually destroy a prop or the whole plane, so it's hard for me to say, "what the heck here".......................
it's too bad that TruTurn doesn't make a 2.5", but since it would cost $40-50 bucks, it probably wouldn't compete too well with the $14.00 GP spinner eh?

anyways, i'll learn to live with it, and use the GP spinners for static display.
i'm also forwarding this topic to Romco.........you never know

RE: GP Super Stearman
 

Summerwind:

I understand your concern for the backplate not sitting flat on the drive washer. Mine sits flat but my concern is that when I snug up the screw that holds the spinner on it will bow the back plate if you torque it too much. If I end up losing it I will go back to old reliable (pic attached) which actually looks pretty good with the cowl on.

Ed

RE: GP Super Stearman
 

hey that looks pretty good......................i may try a 2.25" spinner from TruTurn as well.

RE: GP Super Stearman
 

I'm mounting a 26cc gasser with electronic ignition on the front of a S Stearman. I would like to hear from somebody that is familiar with this airframe about where to mount a on/off swithch and charge jack for the ignition. I'm using a JR heavy duty switch with a charge jack.

I wanted to mount it in the front cockpit but there is just no way to get wires run to the front of the firewall without a big production of extensions and then I don't know if you could find a way around the fuel tank............I might be able to mount the switch on the side of the fuselage just behind the firewall........or I could put it on the cowl. I just wonder if a cowl mount would be to much vibration, and you'd have to hassle with the wires every time you wanted to take the cowl off. I'm open to ideas......there has to be a better way than what I've thought of.

For those of you that have experience with this airframe.........you know what a hassle it is to work in and around the fuel tank compartment and forward to the firewall. It took almost an act of GOD to get some blind nuts up there for my motor mount.

Hope somebody has a good idea......I need one

RE: GP Super Stearman
 

I mounted my Remote Head Lock and On/Off Switch in the forward cockpit. All wiring for the head lock was run next to the tank along the side of the fuse. I also reinforced the forward cockpit floor so I wouldn't push through it every time I hooked up the glow starter or battery charge jack. If you look back a couple of posts (#902) you can see my headlock wires coming out the side of the firewall.

RE: GP Super Stearman
 

roknhs,
I also mounted a gasser in my super stearman. Though mine is a 41cc. I mounted my charge jack and switch on the side of the fuse
just behind the firewall. As you stated, adding extensions or cutting out factory units and replaceing with new, was something I
didn't want to do.
I would suggest you do not mount anything on the fiberglass cowl. You will find it necassary to remove the cowl on a regular basis.
The more stuff you have to disconnect and reconnect means more chances for error. Also the fiber glass cracks, splits, and peels
more easily at cuts and holes. So the fewer of those, the better.
Hope this helps.
Craig

RE: GP Super Stearman
 

Yes, your thoughts help reaffirm what I was thinking............every time I study the options for the swithch and the fuel dot............I keep going to the side of the fuselage behind the firewall too. That gets the job done and keeps it simple.......
Thanks

RE: GP Super Stearman
 

hi, I am overwhelmed with all the info on the Super Stearman I wish I had seen this post earlier. I just finished my Super and enjoyed every minute putting it together. This is by far the largest model I built so far earlier model sizes were in the 60 range. I do have a few comments and questions for anyone who can help out. First the info:-
1- I have installed an OS FX 120 with pump as per GP recommendations. I had originally purchased the model to go with a Fuji Imvac BT 32 that I had received foe X-Mass but GP advised not using this engine as they claimed the airframe would not withstand it.
2- I used JR ST 125 servos and hope they are big and strong enough for the job.
3- Apart from alot of time spent ironing out wrinkles the model quality was A1.
4- The Turtle deck was curved and took alot of coaxing to put it on right.
5- I am using 2 aileron servos instead of 4.
I need help with the following issues.
1- The Manual states you should balance the model at 5.5 inch from the leading egge of the top wing. This way I cant use my GP balancer any ideas how to balance it practically.
2- Putting marks on the bottom of the top wing and placing my thumbls there and lifting the model it seems to be perfectly balanced yet GP claim I will need 18 oz of lead with an OS 120?????? this has totally confused me, I am either not balancing right or what???
3- By linking the top and bottom ailerons I get a different throw between the top aileron and the bottom aileron is this wrong?? ie will it negatively affect the flight of the plane???
4- I will be using a 16X6 prop on the OS which is the recommended mid range prop for this engine , any advise???
Thanks for your help.

RE: GP Super Stearman
 

FoeFoe:

(Balancing) See post# 858, works great.

Ed

RE: GP Super Stearman
 

Lou55
You stated that you did a full user review of this plane, can you give a me link to it?
I finally started building mine and I have been collecting notes from this and other threads. I'm going to use a Saito 150 and plan to use the 4 servo setup. Yes the covering is a drag, I've already burned a small hole in one of the ailerons so I patched it, flipped it upside down and switched it the other side so it's at the bottom. I use to be really finicky when I built a plane but over the years I’ve found it’s not worth it. So I just work slowly and I try to do my best.
aerosman
[sm=shades_smile.gif]

RE: GP Super Stearman
 

aerosman,

here is the link to Lou's review.............................i also burned a hole in one of my ailerons. i finally came to terms with the little boogers and just recovered the upper ailerons. both my kits had excellent covering jobs, but both sets of upper ailerons were just plain rediculous.

Lou's review here gives lots of great info,
http://www.rcuniverse.com/product_gu...93&kit_id=2909

RE: GP Super Stearman
 

FoeFoe
There is an idea with a picture in this thread. I read it yesterday but lost track of it so you’ll have to look for it. Basically it goes like this, on the top of the top wing in the center were the 2 halves join together measure back the given CG distance. Mark it and drill a small whole the diameter of a wire. Put the same size hole in the center of a piece of round or squire stock wood that is about 6 to 8 inches long. Push the wire down through the hole in the wing and on the bottom side push the wire through the stock wood. At the end of the wire attach a wheel collar or something similar to stop the wire from pulling out. On the other end bend the wire to form a hook. Get the idea, now you can hang the plane at the CG with a piece of string or wire to the ceiling or what ever you have available and proceed to balance it. Sorry my version is not as good as the source but I hope it’s clear. And now that I think about it there are a few things that are not practical about this idea so you’ll have to sort it out on your own. [sm=72_72.gif]

The other idea I had, which I plan on doing, I got from a guy who was selling a balancer at the AMA show, don’t have the details with me. Basically I was going to cut 2 large “L” shape pieces out of ½ inch plywood. Then attach them to large plywood base, spaced apart about the width of the fuselage. Rotating the “L’s” 90 degrees and attaching the short leg of the “L” it to the base. At the end of the long leg of the “L” at the top were it will contact the bottom of the top wing I was going to put round nylon buttons. The kind they put at the bottom of furniture legs so they won’t scratch the floor. Am I making any sense? [sm=spinnyeyes.gif] Picture a “U” rotated 90 degrees the bottom leg of the “U’ represents the base. The bottom wing will be some were inside the “U” and the bottom of the top wind will rest on the top leg of the “U” Then you just set the plane on the buttons at the require CG . Again I apologize for wording I’m not a writer.
Good Luck and Great Flying!
aerosman
[sm=shades_smile.gif]

RE: GP Super Stearman
 

Hay summerwind,
Thanks for the info! [sm=wink_smile.gif]
Happy Fluying!
aerosman
[sm=shades_smile.gif]

RE: GP Super Stearman
 

Please ignore this post. [sm=bananahead.gif] I forgot to check the box so I can get e-mail replys to my previous posts.
Thanks
Aerosman
[sm=shades_smile.gif]

RE: GP Super Stearman
 

FoeFoe
I found the orginal post that explains balancing with a wire, less the picture. [sm=49_49.gif] Here it is!
aerosman
[sm=shades_smile.gif]

Here's a simple way to set the CG on this plane (or any bi plane).

I drilled a .046 hole completely thru the top wing on the centerline 5 1/2 inches back from the leading edge. Cut a piece of stock 8" x 1" x 1/4" and drill a .046 hole in the center. Take a piece of .046 wire about 6" long and bend a loop on one end. Insert the wire thru the top of the wing, attach the wood and attach a wheel collar to keep it from pulling out. Set the model on the ground, hook a piece of strong string thru the loop on the wire and lift. Add weight as needed. (Pic Attached)

You could also use this to balance laterally by just rotating the wood on the underside of the wing 90 degrees.
[sm=shades_smile.gif]

RE: GP Super Stearman
 

Opps
Just read one of the posts above the balancing idea is at post #858
Maybe I shouldn't skim through these posts so quickly.
aerosman
[8D]

RE: GP Super Stearman
 

Subject: Balancing the Stearman

Hi, :D
Some people have been asking about how to balance there Stearman. In a previous post I described how I planed to build a balancing tool based on one that I saw at the AMA show. I found the info on the balancer I was referring to and wanted to pass it on.
It’s called the EZ Balancer. The website is www.ezbalancer.com. It’s a nifty idea and works well, but I decide to build my own and save the money.
I hope this info helps.
Happy Flying,
aerosman
[sm=shades_smile.gif]

RE: GP Super Stearman
 

aerosman, How about posting a picture of the balancer you made?

RE: GP Super Stearman
 

Sorry [sm=sad_smile.gif] it's still in the planning stage. I'm still working on the plane. Have you seen the EZ Balancer? The theory is about the same. I have some sketches I guess I can try and clean them up, and post them in a couple of days.

PS: OldScaleGuy you wouldn't happen to be the creator of the EZ Balancer? I am just trying to pass on a good idea [sm=idea.gif] to my fellow RC'ers and have no intention of making any money off this. As I said before if I had the money I would just buy an EZ Balancer.

Happy Flying!
aerosman

[sm=shades_smile.gif]

RE: GP Super Stearman
 

FoeFoe:
Reguarding your aileron issue. The original instructions reguarding the installation of the control horns on the top ailerons, were incorrect. There should have been an addemdum in your kit. The addemdum is also available at GP's website. And last but not least the correction is posted in this tread, alas much earlier. You will have to search for it.
The top and bottom ailerons moveing a different amount is not a disirable situation and could adversely affect flying performance.
I highly suggest you take the time to find the corrections.
Craig

RE: GP Super Stearman
 

Craig:

I can't find the "addendum" on the Great Planes site. Can you be more specific as to where you found it?
Thanks,

Ed

RE: GP Super Stearman
 

Ed,
I went to the great plans site and I could not find the addemdum either. So I got to thinking about it. As I remember the correction was published in RC Report magazine, in addition to being published in this thread. It was in the build review they did.
I am not at home at this time, so I can't look it up for you. However, if you need it, I wrote the corrected mesurements down in my copy of the instruction manual. I can post them here for you if you would like.
Craig

RE: GP Super Stearman
 

I read [sm=49_49.gif] in the review by Al Lewis that he took out the dihedral into the bottom wing to make the plane more to scale. Could someone explain this theory?
Has anyone tried it? I would think would make the plane more acrobatic but less stable. Does anyone have any ideas or thoughts pro [sm=thumbs_up.gif] or con [sm=thumbs_down.gif]?
aerosman
[8D]