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Goldberg Extra 300

Old 01-15-2017, 01:23 PM
  #1701  
PaulWa11
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Thanks for all the feedback! The idea for the flaps was one by a fellow enthusiast I ended up picking up the project from, regarding the weight the wings are totally custom with a foam interior and the fuselage has been redesigned re-built. I guess this is what happens when you pick up a project started by an engineer ahaha.

I will be running a .75 OS AX and DX8 transmitter - Even-though im picking up where he left off i gotta say the over all build quality is remarkable thus far. I will try and post some pic's up as I move along.

Cheers,
Old 01-15-2017, 02:16 PM
  #1702  
bigal126
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If it wasn't mentioned already, I would suggest making the rudder bigger. About an inch to an inch and a half at the bottom will do.
One of my favorite planes to fly.
Old 01-16-2017, 02:50 PM
  #1703  
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To really make your Extra come alive you might need a bit more power than what the .75 produces, unless of course if you are planning on fitting a pipe.
Old 01-17-2017, 10:20 AM
  #1704  
PaulWa11
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Originally Posted by karolh View Post
To really make your Extra come alive you might need a bit more power than what the .75 produces, unless of course if you are planning on fitting a pipe.
What kind of pipe would you recommend? I currently have the box muffler
Old 01-17-2017, 11:24 AM
  #1705  
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Possibly a suitable sized one from Macs Products Mufflers
Old 01-31-2017, 12:25 PM
  #1706  
Thunderbolt P47
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It has been about 2 pages of posts since I last posted an update. Progress to date is that I have joined the wing halves together with epoxy and a whole lot of patience via the trial and error method of lining everything up with the jigs and making sure that both the leading and trailing edges aligned properly. Built the fuse over the plans utilizing the rubber band technique to hold all of the fuse formers in place and sand all of the bulkheads to achieve a good fit. Sized the fire wall and trial engine mount for the installation of an inverted DLE 20 RA. Finished gluing the fuse and formers. Was able to achieve the highly desired straight and true fuselage prior to eyeballing the installation of the wing and tail feathers. Next steps will be: 1) mount the wing, 2) round control surface edges and vertical fin, 3) glue horizontal stab and fin to fuse, 4) install turtle deck and 5) hinge and install ailerons. Once complete reinforcement of the fuse ahead of the wing saddle will be completed. One thing I have to figure out is how I want to install my switches and fill valve. I am thinking about a hatch forward of canopy before the cowl. Any thoughts on this would be appreciated. Some pictures of the progress to date......



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Old 02-01-2017, 01:41 AM
  #1707  
David Bathe
 
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I built/had one... must be at least 18 years ago. Used an OS 1.20 surpass 2, mounted the tank on the CG. The only mod's I did was to make a replacement firewall with 5mm marine ply instead of the laminated version that came with the kit, bought a FG replacement cowl instead of the ABS & used 4/40 hardware and horns. Was it necessary? I doubt it. My advise... keep everything as LIGHT as possible. Don't start epoxying pieces here and there beefing it up. David Patrick really knew his stuff, this is a great model aircraft. Every gram of weight you save will pay you back double in the flying experience.
Just a note, If you're going the large motor option you're going to need at least 3deg right thrust and not 2deg as specified for the .61on the plan. So be prepared to jiggle your engine around to find the correct spot. Don't worry if it looks a little strange... this plane is designed for flying... not looking at.

Last edited by David Bathe; 02-01-2017 at 01:50 AM.
Old 02-01-2017, 06:05 AM
  #1708  
OldScaleGuy
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Originally Posted by Thunderbolt P47 View Post
It has been about 2 pages of posts since I last posted an update. Progress to date is that I have joined the wing halves together with epoxy and a whole lot of patience via the trial and error method of lining everything up with the jigs and making sure that both the leading and trailing edges aligned properly. Built the fuse over the plans utilizing the rubber band technique to hold all of the fuse formers in place and sand all of the bulkheads to achieve a good fit. Sized the fire wall and trial engine mount for the installation of an inverted DLE 20 RA. Finished gluing the fuse and formers. Was able to achieve the highly desired straight and true fuselage prior to eyeballing the installation of the wing and tail feathers. Next steps will be: 1) mount the wing, 2) round control surface edges and vertical fin, 3) glue horizontal stab and fin to fuse, 4) install turtle deck and 5) hinge and install ailerons. Once complete reinforcement of the fuse ahead of the wing saddle will be completed. One thing I have to figure out is how I want to install my switches and fill valve. I am thinking about a hatch forward of canopy before the cowl. Any thoughts on this would be appreciated. Some pictures of the progress to date......



Jeff, nice work.
I have built two of these and have a third still in kit form. Personally, i would not bother with the hatch, you can get to everything you need through the wing saddle.
Old 02-01-2017, 08:43 AM
  #1709  
PaulWa11
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Originally Posted by David Bathe View Post
I built/had one... must be at least 18 years ago. Used an OS 1.20 surpass 2, mounted the tank on the CG. The only mod's I did was to make a replacement firewall with 5mm marine ply instead of the laminated version that came with the kit, bought a FG replacement cowl instead of the ABS & used 4/40 hardware and horns. Was it necessary? I doubt it. My advise... keep everything as LIGHT as possible. Don't start epoxying pieces here and there beefing it up. David Patrick really knew his stuff, this is a great model aircraft. Every gram of weight you save will pay you back double in the flying experience.
Just a note, If you're going the large motor option you're going to need at least 3deg right thrust and not 2deg as specified for the .61on the plan. So be prepared to jiggle your engine around to find the correct spot. Don't worry if it looks a little strange... this plane is designed for flying... not looking at.
Designed for flying not looking at? Are you kidding? ahaha Its like a piece of art! I'm about 70% done with my kit went a bit crazy with the weight saving - Over all great kit and cant wait to fly it
Old 02-01-2017, 11:44 AM
  #1710  
Thunderbolt P47
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Steve, thanks for the input. I will take a good look at it when I mount / fit the wing tonight. With the exception of servos and linkages wanted to keep switches and plumbing out of sight. I bought one of these back in 1998/99 from a fellow in San Francisco when I was stationed at Fort Irwin. It was a great flyer with a Magnum 120FS up front but eventually I ripped the nose off forward of the wing saddle while in flight due to stress and some fuel damaged wood that went undetected. Plane flew rock solid and back then made me look like a much better pilot with the slow and precise landings. Learned that a big prop swinging slow equates to a braking effect at idle that needed to be managed with throttle. This helped me transition to flying warbirds and using the throttle and rudder on landing. Looking forward to some more building and pics to post tonight.
Old 02-23-2017, 04:50 PM
  #1711  
tim allen
 
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Joining the ranks of CG extras here , will post pics but it is an old kit (ugly) that had a Kraft .60 in it , have stripped it and am planning on a ys 140 sport that I have laying around
Old 02-24-2017, 03:09 AM
  #1712  
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Looking forward to your pictures Tim.
Old 02-24-2017, 03:51 AM
  #1713  
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Here is a pic of what the plane looks like now , and a pic of what I think I want . I am redoing this plane and a GP extra in tandem , the CG has a glass cowling , pants , aluminium LG and I am shortening the canopy as per the 260 , was thinking ys 140 but I hear that this is a great pattern ship so I am wondering about using a nib os 110 alpha I was planning on installing in my CG ultimate . Thoughts anyone ?
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Old 02-24-2017, 05:00 AM
  #1714  
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Either engine would be a good choice and fly it fine.
Old 02-24-2017, 05:08 AM
  #1715  
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Hi Tim and welcome to the CG Extra 300L fraternity. The Extra is a great flying model with a fairly wide range regarding power sources and your O.S 110 should provide more than enough grunt up front. Since yours is an old kit it might be a good idea to give it a thorough check on the areas identified earlier in this thread for possible weakness and implement the suggested strengthening tips. Looking forward to seeing the progress pictures promised, also like your planned new color scheme.
Old 02-24-2017, 04:03 PM
  #1716  
rcmichael
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I would go with the Y.S. Power is always a plus.
Old 02-24-2017, 04:25 PM
  #1717  
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Originally Posted by rcmichael View Post
I would go with the Y.S. Power is always a plus.
In some instances more power is a plus, but in this case with the YS 1.40 spinning an 18" dia. prop ground clearance might be an issue, plus the 1.40 makes some real crazy power.

Last edited by karolh; 02-24-2017 at 04:28 PM.
Old 02-24-2017, 08:05 PM
  #1718  
tim allen
 
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Originally Posted by karolh View Post
In some instances more power is a plus, but in this case with the YS 1.40 spinning an 18" dia. prop ground clearance might be an issue, plus the 1.40 makes some real crazy power.
Because of what I have read from ys techs on forums stating to use a 1512 on the ys I am not concerned about ground clearance I am more worried about weight effecting low speed handling per motor weight plus reinforcement. What is driving me to use the ys on this airframe is the fact that I feel the os 110 alpha is an absolute perfect fit for my Goldberg ultimate ! Decisions, decisions, decisions ! Lol and hey , many thanks to EVERY one for your thoughts on this rebuild . While I have flown some glow planes , most of my flying has been electric but I love building and restoring old airframe and I am sort of addicted to the sound and smell of glow , lol . Around here it seems like if a plane needs work nobody wants them a good example being this extra . I got this plane with a Kraft .60 , servos , glass cowling , aluminium LG , glass wheel pants and a nib dx i 6 for 150 . The GP extra I bought at auction with an Ohio scale tail wheel assembly , charge port switch and receiver bat indicator light for the EXPENSIVE price of $3 WHOLE dollars ! Did I mention neither plane has ever been wrecked or damaged ?
Old 02-25-2017, 05:31 AM
  #1719  
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Sounds like you got a real sweetheart of a deal $ wise on those two models. Here is a little something to remember; this Extra was designed for .60 - .75 engines so be wary if using a 12" pitch prop on that YS1.40 engine which will make the Extra a real thunderbolt, something it was not designed for.....just my .02cents.
Old 02-25-2017, 08:01 AM
  #1720  
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YS 1.40 16x10! Wonderful combination. Heaps of thrust, nice middle/lows range flight speed and spot on RPM band. Tried many props (inc many exclusive special made APC's) during the 2x2m pattern days. This was the prop.
My CG Extra (decades ago) had an OS 1.20. The engine of choice back them was the OS.1.08. Also flew Giles, similar size to the CG Extra using a Moki 1.35.. again with a 16x10. That was a miracle combo of size and power. The CG extra was a better flying aircraft though. Keep it light and enjoy.
Old 02-25-2017, 04:49 PM
  #1721  
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Originally Posted by karolh View Post
Sounds like you got a real sweetheart of a deal $ wise on those two models. Here is a little something to remember; this Extra was designed for .60 - .75 engines so be wary if using a 12" pitch prop on that YS1.40 engine which will make the Extra a real thunderbolt, something it was not designed for.....just my .02cents.
Karolh, thank you for the advice , but if it is structural strength that we are thinking of I have a pretty radical idea that involves carbon fiber cloth on all leading edges , cowling , nose and accent strip down fuselage, but I want to leave it exposed . I think I need a very fine cloth and go light on epoxy or perhaps minwax poly acrylic ? Also has anyone modified the horizontal stabilizer into an airfoil surface and and how would that affect flight ? Btw I am not trying to achieve 3d flight as I like pattern flying but if it turns into a rocket as a by product I promise not to get mad , lol !
Old 02-25-2017, 05:03 PM
  #1722  
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David Bathe , thank you for the info ! Here is the thing , I love to Build and try new things so this is something of an experiment and sinc the plane was cheap , solid and light I want to see what I can do with it . Servos will be mounted in the tail for optimal balance and short linkages , the canopy is cut back as per the 260 , and I think the color scheme will be original . I want this plane to stand out loud and clear !
Old 02-26-2017, 08:14 AM
  #1723  
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Experimenting for me is half the fun of our hobby as when I mentioned that I was going to replace the ST.90 in my CG Extra with a modified to CDI Zen 23 everyone said it would become a lead sled, but lo and behold it turned out to be a gem of a combo. I recall that my 80" MW Extra 300 ( original version ) had a flat stab which was later changed to a airfoil section but unfortunately I can't say if the change made any difference to how the model performed.

Last edited by karolh; 02-26-2017 at 08:17 AM.
Old 02-26-2017, 10:39 AM
  #1724  
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Karolh , thank you and funny , I have the GP extra 80" Patty Wagstaf . Btw are u really in Jamaica ? It sure is cool how people from all over the world can talk about common interests !
Old 02-26-2017, 10:52 AM
  #1725  
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Well fellas , ys 140 it is , I am American as they come and I just cannot resist the the urge for more power , lol ! Plus the added bonus of my tank being on the CG without the need for a pump . Now I just need to figure out if I want the engine inverted or side mounted , lol

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