rgpugh

Just started building a new Goldberg Anniversery Cub kit with the desire to replicate a L-4 Grasshopper. (Something to do with my daughter while she is home from college.) Based on what little info there was on the box, I thought that there were contained plans to make an L-4. Silly me! Any and all suggestions would be appreciated. I plan to go to the Travis Air Museum to do a photo study on the L-4 that is on display there. I have built a few kits now, but this is the first scale plane, and first warbird. I would really like to develop into a scale warbird builder, but am in need of a good and patient mentor. Perferably within an hours drive or so from the Sacramento, CA area. Thanks all for your help.

skyraider71

The L4 is one of my favorites. I've long considered building one from one of the Sig
cub kits. I'm in!

thibor

I too want to convert a J-3 into a L-4. I'll be watching this thread closely.

Phil

rgpugh

The Goldberg documentation says to wrap the plane with OD covering, put a couple of star & bars decals on it, and maybe some invasion stripes and that will make the plane an L-4. I believe that there are more differences than that. In particular, the Grasshopper is known for its greenhouse cabin. I've just ordered a "photo paak" and documentation from Bob's Aircraft Documents. We'll see what I can gleen from that. Still trying to arrange access to Travis. The museum is on base so I need to find some one who has credentials to take me as a guest. My father-in-law has credentials, retired B-52 & C-5 nav officer, but timing is a challenge. I will keep you all informed. Suggestions are appreciated.

Mtthwacrss

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I recently accuired a gloldberg cub and have been looking at a lot of cub pictures to decide on either a J-3 paint sceam or weather to do a L-4. I have seen some pic of what looked like early L-4s with out the green house. I would like to do the green house if possible. Has anyone seen and plans or anything to convert the goldberg kit?Good luck with your cub and I will be watching to see how it goes for you.

rgpugh

I was able to visit the air museum at Travis in December. The gracious people there gave me permission to climb over the rope and take as many photos that I wanted of their L-4B. Just so long as I treat it as if it were my very own frail Grandmother. From there I've been trying to make the Goldberg as scale as possible. I've added a turtle deck behind the rear seat, and am using a Du-Bro semi-scale tail wheel system. The balsa sheeting on top of the wing, over the fuse is being replaced with 0.03 in clear co-polymer plates. I've enlarged the rear side windows as much as possible without sacraficing structure and plan to use the clear plates there too. I hope to use the plates in that area behind the wing and in front of the turtle deck end. If that does not work out, plan B is to use clear Monocoat instead. I think that to be anywhere close to convincing as an L-4, you have got to include the greenhouse cabin. Otherwise it's just another Cub. That was the point that I was trying to make in my last posting. The rudder is now a pull-pull system just as the full scale is and I am working to make the ailerons pull-pull as well. I should have the aileron control systems completed by the end of the month. My biggest disappointment so far is the amount of cowling that I had to cut away to make it fit over the engine. The engine is a .52 Evolution glow with a Slimline muffler. At this 1/6 scale, the J-3/L-4 frontal profile is just really narrow. The only solution might be to use electric power, but then it will not sound anything like an airplane will it? Is my bias showing?

Thanks for your replies, and keep them coming. I'll keep you informed.

thibor

Thanks for the info on the green house!

Can you show us some detailed pics? I'm planning on converting a 1/5 sig J3 cub to the L4.

Thanks,
Phil

GarySS

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For pictures of an L-4 or any type of aircraft do a Google Search out on the general Internet. Also go to airliners.net and go to their search engine and do the same on L-4 and/or Grasshopper, etc. There was also an "O" type designation, but the exact number escapes me at the moment. O-59?

rgpugh

I've put all of the images that I have on my Facebook site and have left them open to everyone. Simply search Facebook.com for Rod G. Pugh. You should be able to find what I put up. There are three files. One contains the photo study of the L-4B, s/n 43-753, that I did at the Travis Air Museum. Another folder contains images of my building project. And the third file contains images of L-4's that I gleened off of the internet.

Let's continue the conversation.

rgpugh

GarySS,

As you can see in my reply to Tibor, I've uploaded all of the L-4 images that I can, including images that I gleened from internet searches. You are correct. Before being given the L-4 designation, the USAAF Cub was called the O-59. Do you know if the O-59 had the greenhouse cabin, or was it simply a J-3 painted olive drab with star and bars?

GarySS

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Well, you've got me on that one. I just did a quick airliners.net and google search myself on the "O"-59(note the letter "ohhh" is used; not zero) and they all brought up a greenhouse fuselage. If that is also what you have found in your more extensive searches then maybe it was more than just a paint job.

ARUP

The Goldberg Cub is a fine flyer and you will love it. The gear as designed will gradually bend so make an extra set of struts to be mounted to the rear of the fore struts and solder their ends to the front ones. Fill in the gap with balsa and cover. Just throw away the silly screws and plastic clips of the LG strut fairings! Make bungees covers and supports to fit gear. The stab is larger than scale and can be reduced without affecting performance. Better yet, make the stab in 2 halves. After getting the fin- fuse junction covered you can glue 'plug-in' the stab halves (which have dowels at leading and trailing edges) and then attach support wires like the real one. To anchor support wires drill 1/4 hole at proper location and glue into hole a 1/4 dowlel. It won't compress when bolts/ nuts tightened. You can shorten the ailerons to scale length without hurting performance but you cannot increase their chord to scale dimension without a major wing overhaul. For the greenhouse- when you laminate the ply for fuse just sandwhich some carbon fiber 'hair' in there with epoxy. Very strong and you can make your windows bigger. You can make wings 'plu-in' but will have to build carry thru spar and functional struts. Brass round or sqaure tubing work well and is what I did for my PA-12 coverted from a Sig Cub. This will be great for sport scale. I've built 4 or 5 of these. Good luck, ARUP

Mtthwacrss

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I found these pic's of some early L-4 or O-59's. I think the first ones were straight cubs and the green house came later. I believe Hap Arnold or MacArthur said we just put an ODpaint job on the cub and sent it to war. Some of these were captured by The Germans, but there at least 2 and the NE-1 that appear to be straight Cubs withe diffrent paint.

mebtraveling

Based on "The Fighting Grasshoppers, US Liason Aircraft Operations in Europe 1942-1945" by Ken Wakefield pg. 144, the YO-59 (4 for evaluation) and first 20 (possibly an additional 120, it's not clear) O-59s were unmodified Piper J3C-65s.The O-59A had the "modified cockpit enclosure, radio, generator, etc."

The YO-59s and O-59s became L-4s, O-59As became L-4As, and then the series continued with the L4-Bs which had no radio.

The U.S. Army Aviation Museum at Ft. Rucker AL has an example in their collection. It's not real clear, but click on the photo/linkof the Louisiana Maneuvers on the museums Web Site and you can see it in the display:

www.armyavnmuseum.org/museum/exhibits/exhibits.html

Regards,

Mike

Daddyo57

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I thought I might revive this thread if you guys dont mind... I am mostly finished with my Goldberg Cub Grasshopper. I put a sweet running old (low hour) Saito FA 80T in her with a Fiberglass Speciaties Cowl. I also hate the stock gear so much that I fabricated a set of my own gear that seems to work just fine, wife still needs to make my bungee covers tho. She weighed in at 8 lbs and I covered her in the Monokote Olive Drab with Dove Grey on the bottom. I just didnt want to do another yellow Cub and have never done a military scheme. I have a whole new respect for scale airplane guys now! I have done the maiden flight and it flies great. I do need to do some more detailing on her but I am not going to go too nuts on it. I intend to sell this Cub to finance other projects and I had a great time building it and flying it. BTW, I found the Monokote flat Drab color to be very difficult to dupicate in paint! you can get the color close but to get the same reflection is a job for master painters, it was a blast mixing paint for hours though!

rgpugh

Nice work Daddyo! Your work on the gear is great! It looks as though you also re-did the wing struts. The gear and struts were definately weak areas in the Goldberg kit. I am interested in more info regarding your efforts in thses two areas. Since I really don't have any metal working tools, I might ask you to consider making the gear for me. Are those the Du-Bros Cub wheels? What ever they are they look great too. The Du-Bros Cub wheels are just so out of line with the prices of any other ~3in wheel.

My own L-4 is moving ahead, but slowly. Same excuses as everyone else, time, money, family. I do need to post some up to date photos. I'm not very happy with the Goldberg dummy engine or how much of the cowling that I had to cut away for my engine/muffler system. Any suggestions that folks have on making that part of this project more scale would be appreaciated. The greenhouse portion is looking like it will turn out pretty well.

Just returned from OR to pick up my daughter from Oregon State, and made time to go to the Evergreen Museum in McMinnville. If anyone who has a passing interest in aviation/aerospace is pass withing a days drive of there, go. I spent 8 solid hrs there; totally exuasted, and could have spent many more hours there. They even had an L-4H on display.

Daddyo57

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Well rgpugh maybe if I was retired I would fabricate another set for you, but to be honest, it was a royal pain! LOL but I wanted to see if I could do it. I am pleased with the results but you need to be able to weld steel as well as iron to do this job, as it was I had a friend do the 4 small steel welds and I did the rest. The Cub however is for sale here on RCU ! I am getting into 3-D type airplanes and am selling the sweet running Cub. I agree the DuBro wheels are insanely expensive but I just had to pony up for them as the do look cool. I used regular wheels on my old Goldberg Cub with 1 inch automotive freeze plugs for wheel covers and it worked ok. I highly recommend buying a Fiberglass Specialties Cowl for you Cub, the stoock cowl simply is too cheesy for more than 1 season. They sell them with 1, both or no engines on them and they are molded in. I am very interested to see how your geenhouse was accomplished and the finished result!

OLDFLYER2

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There are many L-4 photos on "j-3 cub.com". I actually helped restore a full size 2 years ago. It did not have the green house but the customer wanted one so we bought a set of original plans and manufactured it exactly as original. It was a lot of labor but worth the effort as it turned out to be a show stopper. the more difficult parts to duplicate (besides th greenhouse) was the rear seat . The GIB (guy in the back) ha s to be able to turn around and face rearward to operate radios etc. It took a lot of research to duplicate this. I'll try to locate my pics and publish them soon. Good luck and happy modeling.

rgpugh

Hello L-4 friends. Just dropping a note that my Goldberg L-4 project is still on the workbench. I've gotten bogged down with interior details. I'm not pleased with the looks of the side-ways mounted engine sticking out of the side of the cowl. condsidering inverting the engine, but I don't know is there is a muffler system that will work with the Evolution .52 that I had bought to power it. For safe starts, inverting the engine will probably also require installing an on-board glow driver. Obviously motor mounts are going to have to be re-done as well. Nothing worthwhile is easy is it? That's why we do it. Any thoughts or suggestions regarding the engine/muffler?

ibindn

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Hey RGPugh,
I have a Sig .040 kit that I started some time ago. Reading your post has me thinking I should get back to work on it.. I just need to finish the wing. I will post a few pictures after the 4th...D

M250

I started building a SIG 1/5 scale cub. Another club member had 1/4 scale plans for a L4 grasshopper. We took the plans for the cabin area and shrank them down to fit our scale. I am going to try and build it to these drawings. Everything looks like it will work. Has anyone else tried this route before? Let me know.

szig

Nice project.

Please post pics of your progress.

Good luck.

wheels

No fancy gear on mine but I followed the kit recommendations to recreate sort of scale looks with brass tubing.

I used an aeroglass cowl and modelmaster "dark green: spray paint to match the ultracote olive drab and I'm pleased with the results, it is a much closer match than the pictures would lead you to beleive.

I also chopped the inside 10" off the ailerons, built servo bays in the wings and created flaps. I've never had a flap equipped airplane before so we'll see how this goes.

It's still waiting for the power system (turnigy motor and speed control) and wing struts, but I don't mind showing her off a little. (don't mind the masking tape :P)

Nothrottle

Greetings Cub fans. I am building the Sig J3 1/4 scale clipped wing cub and I am planning converting to the L4 Grasshopper. Tedious search until finding Pugh's post as it clearly shows most of the framework needed for the project. The fuse is at the right stage to begin the L4 framing. Thx Mr. Pugh for your post and others as I dive further into the thread