ve3cga

another question as I am getting ready to join the wing halves
is there Dihedral on this wing
I see there is a 91 degree tool for the spar so does that mean theres 2 degree dihedral total on the wing
also confusing to me is
when joining the halves the manual says to use the tip brace tool and the root brace tool
so does the tip and root spacers take this into account
and cutting one spar from the plan and the other using the 91degree guide just help when joining the halves up

final confusion, when I built the wing halves, I believe I missed the part where it said to join the wing sheets together
I still built them on their on their respective layouts. pinned the 3 ribs that had the breakout tabs, built them and sheeted a per directions
so now I've got the plans together and am fairly sure you flip the wing over so the other side without the sheeting is facing up

is the side thats now facing up the top or bottom

this takes me back to my orginal question of dihedral. which the tip and root ply spacers would take into account
I would guess that the spars that were cut 1 degree out from one another would now match

I 'm going to blame todays stupid spell on getting the "seniors" flu shot and the shingles shot yesterday

hope somebody can straighten me out - going to re-read the wing section of the manual again but I'm beginning to think at this point I'm looking at the bottom side

both wing halves came out great but I'm going to wait until I understand the dihedral and which way is up or down before I join them

David Bathe

bignasdy

Did you ever get the thing finished? I built one in like 1990. I snapped the right horizontal in half in a snap roll and made it around to land in a field hitting a trashed box spring destroying the plane. Here's a pic.
d

ve3cga

but the plane is finished and waiting for weather and wind to calm down
The fuse sides and bottom are 1/8" marine plywood and the rest is either light ply or balsa
Canopy is from my old extra230 with a modified frame for this plan
engine is a MDS148 and hi speed trials at the field were very good, actually had it a few inches off the ground before throttling down
This engine is a beast.

for some readon I cant upload pictures or links so...
I posted a picture on my QRZ radio page: ve3cga click on the rc plane icon and it will take you there
then click on the extras picture to get a full screen version

Britflier

Has anyone built/flown the cloned CG Extra from Outerzone ?

Folgore88

I am still building, unfortunately I got stuck, finished the wings and started the fuselage. I have had little time. I hope to continue building next spring.

Miryan

First time poster here.

I am currently building the Goldberg 300 with plans from Outerzone and the short kit from Balsa Work Bench.

Thank You! to you all who have contributed to this thread. I have learned a lot!

Britflier
I am currently nearing the the final stages of construction - building the canopy. Like you I measured the wing incidence at this point and have the exact same wing gaps you show in your previous post as well as the same -.5 degree wing incidence. I am perplexed. The canopy and laser cut canopy former's fit perfect as is. Anything I do to correct the negative wing incidence will negatively effect the canopy fitment as a result.

I was wondering if you found a solution? Or continued with the build as is, if so, how did it fly?

ve3cga

I can tell you that was the best scratch built I've done
Everything was rough cut with a dremel/ hobby saw and knife then sanded to match the outline of the piece
I laser print the part layouts then spray with 3M photo mount so they are mounted on the rough
wood pieces...cut slightly outside the lines then sand so they match
Its not CNC but MNC or "manual"
wing had no incidence, I used the wing braced that were in the plans
and I have a very flat bench
Probably going to have to mount my skis on to maiden it, we just got a bit of snow
I put a MDS148 engine on it and will have to re balance as its too nose heavy. I'll leave it a bit nose heavy for starters
I cover my planes with photocopier laminate, its very thin but was free, commercial copiers toss out part rolls
I paint it later after first flites
The only serious mod was the canopy. Its from my old extra 230. the frame had to be lengthened to fit the extra300 plan
I'll build a fiberglass cowl once it flies good.
That MDS 148 is a monster... the plane shakes like a NHRA fueler at idle then stiffens up after any throttle
I taxiied it several times and it tracks straight and after givin it 1/2 throttle it starts skimming the grass.
It really wants to go
One other mod I did was to move the landing gear forward until the wheel axles were even with the leading edge , I hate nose overs
Looks like the photo is going to work this time, hope so

bignasdy

I can tell yall that my SuperTigre .90 was perfect fit, but still way more power than needed for the GBE
d

Britflier

Miryan, I ignored the -ve incidence on the wing, went ahead and completed the build. I have only flown it about 10-12 times, I’ve been flying my other planes instead. The Extra flew “OK”, but I was not comfortable with the performance. Since the last flight I have made some changes to the c of g. I have moved it to the forward limit as shown on the plans. I also put some more sidethrust on the engine. I also added some soft material spacer to the front of the wing saddle. The canopy still fits but is tight on the wing.
I will keep you posted on how it flys.
The Outerzone plans show 0, 0 incidence. Maybe the kit cutters files did not translate exactly ?
Or maybe the native Goldberg builds 0, -0.5 ?
Can anyone confirm?

Miryan

Thanks for the reply and info Britflier!
ve3cga: Cutting all of that lite ply to plans manually and getting it to fit is a lot of work! My hats off to you sir! Glad to hear your happy with it.

Well, I finally got some time to check and triple check the plans, laser cutting and my work so far, to try and figure out where the issue is.

First off, I went old school and painstakingly transferred the wing center line from the plans to my fuse side to verify it wasn't my gauge. Sure enough, the center of the leading edge of the wing lined up perfectly with my marks. The center of the trailing edge was just over 1/16 high, not quite 3/32. Dang! Same thing my incidence meter was telling me, so at least I know my gauge is accurate,

After much tinkering to see what went wrong, I figured out the error was on my end.

The plans show the wing trailing edge and ailerons at 1/16 thick. I forgot that I had consciously made the decision to taper them to 1/8" thick thinking 1/16 was going to be too thin and fragile. I obviously didn't think that through too well! The thicker trailing edge lifted the back of the wing in the wing saddle Also, it appears I compounded the problem by not getting the trailing edge blocks at the wing root cut square as they are tapered evenly but slightly pointing down, further lifting the back of the wing.

Because the U-Shaped gusset ties into the top of the wing saddle right where it needed to be sanded to correct this. it really complicates things. My fix was to leave everything at 1/8" and sand "saddles" into the wing trailing edge where it contacts the fuse wing saddle, thus dropping the trailing edge down. It worked, I just hope it didn't weaken the trailing edge too much and bite me in the A**.

ve3cga

thanks, its rewarding to almist whittle out the pieces. these goldberg plans are awesome, the ultimate bipe was excellent to scratch build

anyway if this week is going to stay sunny, no rain ,no winds over 15mph I'll be trying the plane out

I just put 7oz on the rear of the fuse to balance it with just a bit of nose heavy

snows gone here at the moment and with the sun the ground isnt squishy
Managed to fly my new scratch built electric 4' ultimate stick and it was almost boring except it was snowing so hard I didnt dare flying above 50'
Had to land after several passes - looked at the transmitter and it was covered with snow. the plane flew perfectly
Luckily no water inside the controls

Once spring comes along I'll try my ys110fz in it, I tried it this winter but it just wasnt reliable, Ran too rough

karolh

Wishing you best of luck with your maiden flight. It's a Goldberg so I'm pretty sure it's gonna fly awesome. By the way, what does your model weigh ?

ve3cga

thanks, I hope it does as well. first couple flites are going to be without canopy just in case...

weight as of 10am is 9lbs 6oz
heavier than I wanted but both the 78" models I had were 10-12lbs if memory is working ok

karolh

Over it's now 27 year life span my CG Extra has with different engines weighed from 8.5 lbs with an ST.61 to 11.25 lbs with a stock G23 gasser and the rather extreme weight swings did not in any way affect the model's excellent flying habits. Eventually I had the small engines and Zenoah Guru Ralph Cunningham convert the G23 to electronic ign. which lost it all of 16 ozs. but more importantly I was able to remove the 10 ozs of ballast weight from the tail of the fuse. it needed to balance. Now with an AUW of 9.lbs.10 ozs and with unlimited verticals and with landings as easy and forgiving as a trainer it's a real hoot to fly.

At 9 lbs.6 ozs I'm quite sure your model will be a dream to fly too. Hopefully you meant flying it without the cowl, as attempting to fly it without the canopy in place might actually do more harm than good.....just my 0.02 cents.

stang151

My latest , C/G Extra 300, DLE20RA . Got this kit a year and a half ago at our club's swap meet , came with a glass cowl and pants but the canopy was trashed. was able to get a new canopy and alum. gear from a friend in the club. Built to the plans for the most part except ,put the ele. servos in the rear, throttle and choke in the nose,fuel tank on the c/g and beefing up the firewall and landing gear area with alum. angle stock. Came out a little heavy ,I think, but I haven't weighed it yet.Did the maidan last Sunday, flys
REALLY well, got 2 flights on it and am very pleased.

stang151

Just went out and weighed the Extra , came out at 10 lbs on the dot with 3/4 tank of gas, so better than I thought. The C/G Extra and the DLE 20 Ra make a great combo.

karolh

That's a very nice looking model you've got there. At an AUW of 10.0 lb I'm not the least surprised that it flew well, after all its a Carl Goldberg Extra.

Miryan

Sheesh, I can't believe it's been over 8 months since my last post but I finally finished and flew my cloned Golberberg Extra 300 from Balsa Work Bench. I am VERY happy with it! Right off the board it fly's much better than my Pilot RC 67" Laser (Gas) ever did. The maiden took 1 click of right Aileron and 3 clicks up elevator.

Just a few notes for anyone interested:

Working out the wing incidence to get it to zero and filling in the gaps in the wing saddle I believe are a must. Also, zero,zero on the engine and stab.
After 12 flights the CG is at 5 1/2" and the plane is unbelievably stable. Just a very slight bit of down "pressure" on the stick during 45 degree inverted up lines.
Vertical climbs are perfectly straight up, indicating the 2 1/2 degree plans recommended right thrust was perfect.
Power off vertical dives show a very very slight pull to the canopy.
Slow Rolls and 4 point rolls track straight and precise.
It will Knife Edge forever and exhibits no roll couple.

All up weight ended up at 7.75 lbs. I tried really hard to keep it as light as possible and this really seems to have paid off.
RCGF Stinger 15 gas engine on a 15x7 Zoar Wood Prop. I tried a 15x8 and it was really close as well, the 7 pulled a little better during climbs.

I would highly recommend this short kit to anyone who has a few kit builds under their belt and is looking for a great sport or aerobatic plane.

Gray Beard

My Feedback: (-1)

The CG Extra is the best flying Extra I have flown. This winter I plan on recovering mine. I have not flown in about a decade but now I live a few miles from a very good club. I have been working on a few planes but ran into a problem UT should have that corrected next month! I still have the plans, templates and instructions on hand for the CG Extra. Once upon a time here on RCU we used to send other builders copies but last year I got screwed by a fellow and decided to no longer do that. The price of the copies has gone nuts!! Karol, I saw he gave a reply, is now looking for another CG Extra kits. If anyone has a kit to sell write to Karol. He posted on this thread not too long ago!

RACE 66

Grey Beard..

Where have you been? I've enjoyed your input on the Extra through the years. Glad you're still above the ground. Good that your still
bleeding on balsa. Take care.
Mike

Gray Beard

My Feedback: (-1)

I stated years ago that I was leaving RCU because it turned into the same questions over and over. I think it was the what size prop question that got me. I moved from Vegas back to Calif. And had no field to fly from that was close. I gave up RC in 2015. We just moved to Arizona and I'm in the process of getting some planes back in the air! I have a really nice club just up the road from us! It took a while to figure out how to bind the RX and TX too. Then it has been a chore just to figure out how I did my programs and set up in my old radio. I should be back into flying in the next month. All my engines were frozen so that has been first. Now I need new batteries and a charger. FYI, I still have my CG Extra but I really want/need to recover it!! I'm still on this side of the grass. RCU looks a bit defunked?