Here is a couple of pictures of the completed plane.

Bruce

Hey Dauntae: Where do you fly your Extra. I am down here in Falmouth and fly at the OMAC field. I assume you fly in the New Bedford/Dartmouth area(?)

That's a really nice looking model which I'm sure flies just as good or better than it looks. IMHO the Goldberg Extra is just about the nicest flying plane of it's size there is.

Karol

Yes I fly in Dartmouth mostly at the Bristol county R/C club, It's at a farm behind Salvadors ice cream, A smaller club but not a bad field and a pretty good group of members.

Dauntae

Finally got some flight time. OS 91FX , APC 16X6, 17 oz graupner tank, around 10lbs. Needed to increase elevator throw on low rate to flair for landing. With alum gear forward a bit no problem on grass. Blocked one exhaust outlet on Bison. Engine runs great but won't shut off unless I block intake. Smoothest flying plane I have ever owned.

Good for you, but you can't say we did not tell you so

Karol

I am very glad to see this thread pop back up. I tried a search and did not find it. I started a CG Extra 300 about a month ago. I just started covering the wing last night but have alot of work left on the fuse. I plan on finishing all hardware on the fuse and weighing before disassembling and covering. I am using a OS1.20 2s as I was told that was the ticket for this plan. Probably because it runs at such a low RPM complared to the 90 2s. I guess it runs more like a four stroke but much less weight.
I am glad to read that this thing will nose over as I had a plane before that would do that and that has got to be fixed. I haven't mounted the LG yet so it gives me the opportunity to move a little forward or angle. I had already used a solid block for the gear and bought Dubro fiberglass gear.
I am still undicided about mounting the elevator servo (s) in the tail. I don't like the setup on the plans and I may need the weight in the tail. Any suggestions? I liked the picture of two servos on either side of the Pull/Pull and may use something like that. I will completely assemble the plane before covering and if the weight is needed I will install in the tail although I don't like the looks. Thanks for the suggestion on the larger tank as all I could find was a long tank at 12 oz.
I had wanted to tint the canopy so I may try the clothing die unless someone else has a better Idea. I had considered complete black-out but to fly IMAC you need a pilot and if blacked out you wouldn't be able to see him.
Thanks all,
Mark

The OS 1.20 should prove to be a good powerplant for your model. Several persons have used the Graupner square 16 oz tank in the small tank compartment provided. Make sure that you strengthen the landing gear attachment area of the fuse when fitting a fiberglass or aluminium landing gear unit as the fuse has been known to fracture or break in this area due to stress from hard landings.

For that size engine ensure that you use one servo per aileron, which should really be mandatory on a model of this size. The final placement of servos for the rear control surfaces can be at the descretion of the builder as long as proven practical methods are used.

Karol

Putting the servos midway down the tail worked well, I think my post was on page 3 about it. To get to the servos I put the punched out ply back with tabs in the corners to and it definately helped with the CG with a Saito 150 on the nose.

Dauntae

I posted earlier on this thread but never added any pics of my plane. These are a little fuzzy but you can get the idea.

I use a 91FX with a bisson muffler glass cowl and gear. 2 elevator BB servos plus 2 BB 77 oz aileron servos a pull pull on the rudder Hi torque 635 HT.
The plane weighs in at 9.5 lbs and flies like its on rails. I did go to a larger tank 14 oz I think can't remember now. The 91 FX sips fuel. I have a 120 YS I considered putting in it, But i'm not going to cut the cowl up to do so, when the 91 is plenty for most of what I do. I did make a larger rudder when I built it, But I don't fly it 3-D I have other planes for that, so why mess with perfection.
IMO its one of the best all around planes ever designed.

If you look close you can see the QA inspector eyeballing things over up in the corner of the one pic *S*

I have basically the same setup with the same engine. I did have to block one outlet on the muffler to get the engine to run properly. Is your 91 running OK with both exhaust outlets open? Also,what prop are you using?

My engine runs fine with both open and to be honest I was supprised. 13x6 or 13x8 APC 12,500 RPM if memory serves me correctly. After I get more run time I may go to a larger prop we'll just have to see.

Let's talk exhaust.
I am installing a OS 120 AX sideways and have bought a pitts muffler. The down tubes are very far forward of the cowl cut out.
How have you all delt with that? I see in some pictures that some have cut the tubes short enough to get the cowl on, then put silicone tubes on as extentions.
It would be nice to get the tubes/pipes further back and let them hang out of the cut out. Has anyone seen a offset for the exhaust manifold that would give the corect angle?
Speaking of cut out. It looks like the stock ABS cowl has a raised section to be cut out as a air outlet. It looks like in the pictures I have seen that these are not cut out. Looks like a cooling problem to me.

Mine is hard to see but it has been cut out to allow for cooling 3 to 1 is a good rule to follow.
The exhaust tubes are what they are and to my knowledge the angle is about standard, You may be able to have one special made for your needs, Or build your own. But I found buy trimming off the ends and using the tubes has worked fine for me in about every thing I have used it on. Where a person will get into trouble is if the ends of the tubes have been swedged down to make them smaller or they have inserts installed in them for more tank pressure. If you cut that off you will need some sort of a restrictor in its place or a pump reg ect to fix the tank pressure problem. While pluging off one hole does work I have seen it cause a loss of RPM's in some cases.

How is everybody fueling their plane? I have not been able to come up with a plan that I like.
Mark

I setup mine with a fuel dot on the side of the Cowl. Using a 3 line system - 1 to carb (with clunk), 1 to muffler (vent to top of tank) and the third (with clunk) as the filler to the fuel Dot. Works Great. Only thing is it can be a little messy as you pump in fuel until it comes out the muffler. Have not had any issues with flooding of the engine.

Bruce

Thanks for the response,
I would have thought you would have a flooding problem with the carb line still hooked up. Also thought about allowing it to vent through the muffler but thought that might be messy.
I concidered using the fueling valves but those go bad all the time. I haven't mounted my cowl yet so I am not sure if I can get to the fuel line through the cowl. If I could, then I could pinch off the carb line with hemostats and fill through a fuel dot and third line as you mentioned.
I will be running the OS 120. There has to be a better way.
Mark

My setup is exactly like Skywriter's. Works fine.

I used a dubro fuel filler,kept things simple on this one, yes I know they can and do go bad but there a easy fix, I have a rebuild kit in my fight box if I need it. Thats the only one I have all the rest are 3 line set ups. Must have thought I needed it for some reason, but what *L*
Oh unless you plug the hole in the muffler the fuel will never flood the engine when filling like is described above.

I have finished most of my CG Extra build. I am still waiting on the Fiberglass Specialties Cowl and wheel pants.
I really like this plane. It is my second build and hopefully will last me longer than my last. I tend to crash with less air time than I have time building.
I think that the build went very well with the exception of the landing gear mounting. I new from the start that I wouldn't use the stock wire gear. When everyone on here talked about the plane nosing over on the runway I decided to tilt the geat forward. I think that I went too far. I think they are ugly. Maybe the wheel pants will hide most of it. I am worried that at that angle they will be aero dynamic the wrong way.
I got a couple of runs on the engine yesterday and it ran very good but I did see alot of air in the fuel line. I first thought it was foam but when I tried to empty the tank it wouldn't pull anything but air and foam. I must have a air leak in the pick up tube above the fuel level.
I hope to maiden this saturday so I too pictures first.
Mark

Don't worry about the landing gear, with the wheel pants on you won't notice the gear at all. I'm in the final stages of finishing mine. I have to install control rods and do the painting.

Cheers!

Jollidude

Your gear looks ok to me, if you do go to far forward the plane will like to hop and bounce when landing ,but to me you don't appear to have that problem, I did mine real close to the same way, Looks good and lands fine.
Rule of thumb is the axle is on the leading edge and you appear to be there.
Good Luck with the maiden flight lets us know how it went.

Thanks, I just would have prefered to move the mounting forward rather than slant it forward but then you have cowl clearance problems. I think I am a good bit ahead of the leading edge. I had heard that one before. I may end up angling it back a little at some point.
What is everyone using for a rudder pull-pull servo. This is my first p-p setup. Seems like there will be a lot of tension and wear on this servo. I am using a JR 821, which is digital and BB but I am wondering if two bearings and metal gear would be best. I don't want to overkill but don't want problems.
I have upgraded all of my linkages and horns. I am putting a long arm and ball ends on the rudder servo tonight.
Mark

This control linkage stuff is so neat that I probably got carried away.
I used Dubro Heavy duty control Horns and arms on all surfaces, ball links at the servo ends, dual servos w/ Sullivan Gold-n-rod pushrods for the elevators, Sullivan Push cable for the throttle and Dubro Heavy duty Clevises all around.
This thig is ready to maiden but the wind has been 25 to 30 knots every day this week in Florida. Maybe this weekend I can get out before the wind picks up.
Mark

I just about have the plane the way I like it. I can pick it apart and find things to fix but in general it came out very nice.
If I were to pick, I would repaint the cowl and pants as I did it when it was raining and they turned out less than glossy.
I found that my motor offset was way off, I used washers and did not measure. I just lined it up to the cowl and I found that Goldberg had put the cross hairs wrong on the firewall by 3/16" so lining up the cowl gave me 8 degrees insead of the 2 degrees recommended. I have remounted the engine and it loops much better now.
I have included the most recent pictures and here is a list of parts.

CG Extra 300 kit
OS 1.20 AX
16x8 APC prop
Fiberglass specialties Cowl & Wheel pants
12 OZ dubro fuel tank
fuel dot for third fueling line
1/5 scale pilot (not installed yet)
Gold-n-rod pushrods
Dubro heavy duty control horns & ball links
Dubro fiberglass landing gear
Spektrum AR7000 receiver
JR DS821 Digital servos all around
Dual elevator servos next to pull-pull servo
Li-po battery
Angles LG forward to prevent tip-overs
AUW 10# 1oz.