Extra 300 50cc scratchbuilt
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Extra 300 50cc scratchbuilt
I'm currently working in a winter project while I have some free time from my job. It's a Extra 300 50cc constructed from a set of plans for a 36% Extra. The plans were shrunk in order to achieve a 88" wingspan and a 80" of length.
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RE: Extra 300 50cc scratchbuilt
Here are more images of the fuselage assembly. Its already looking like a fuselage. I don't have an idea weight wise of the fuselage but it feels light to me an really strong. I need to weight it to confirm it. But I don't have a weight scale handy.
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RE: Extra 300 50cc scratchbuilt
Hell no!! I wish. But I been only working for the past 5 days. I had all the pictures and decided to post them all together. As right know the fuse is almost done and I'm working into building the custom cowling and the sheeting.
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RE: Extra 300 50cc scratchbuilt
Well fuselage is already glued and now I'm moving forward (literally). I started putting the cowling together in foam to shape it to size and after that to lay down the fiberglass.
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RE: Extra 300 50cc scratchbuilt
I will upload the files during the week because I need to convert to PDF because RCU is not compatible with DWG format (I can send them in the original by email). They are in Portuguese but anybody can translate them using any web translator and drawings have the universal language. One thing here before you find out if you change the scale some parts will get shrunk in the process changing the fit but as I found on mine there were minimal. I'm using 3/32 birch plywood and bass wood instead of balsa I kept the big stick sizes (3/8) close to the original. For the stringers I went up to 1/4 and just draw the parts in the original size and then opened them up to a 1/4.
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RE: Extra 300 50cc scratchbuilt
Rough sanding of the cowl is done. I started by hand using a Great Planes sanding bar but after a couple of minutes I gave the orbital hand sander a try and never looked back at the bar again. Way faster and way better finish using just little pressure. Now I just need to start doing the final sanding and detailing of cowl (intake, bottom) this is the point where patience pays off.
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RE: Extra 300 50cc scratchbuilt
Since the weather is currently cold and I can't lay down the fiberglass because it wont dry properly I started building the stabs. After some trial and error in the airfoil because the original plan used foam cores and I decided to built up the stabs I manage to get the formers done. I glued a piece of wood at the centerline of the 2 ends and then measured from the centerline into the flat surface then I flipped the stab and did the same for the other side that way i was able to determine the thickest point and from there I drew the airfoil using the small end as reference but increasing the measurements to the shape. I dry fitted the parts and then glue them together.. I still have some final sanding to do before sheeting them. Also I haven't decide where I'm gonna place the servo in the stab. But I have space available to install it in the stab instead of the fuselage.
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RE: Extra 300 50cc scratchbuilt
Today I got all the wood for the stabs cut and glued together the first one together. Now I understand the words from my trade school teacher. " The first part of a prototype is always the most difficult because you not know how is gonna end up at the time of the assembly ". Tomorrow i will glue the other side and I will start building the trailing edges.
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RE: Extra 300 50cc scratchbuilt
It's been a while since the last pictures and updates but I'm been doing regular Christmas stuff (shopping, shopping, cleaning, etc.) Here are a couple more of the stabs. This have taken me longer than expected because I been doing a regular wood build up and not the foam core as used in the original design. Also I incorporated the servo inside the stab instead of the fuselage.
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RE: Extra 300 50cc scratchbuilt
I used regular paper to make a tube for the carbon fiber tube to prevent the resin to stick to the tube. After that I rolled out the paper tube I cover it with 2oz fiberglass (2 full spins). Then I wick the fiber with plenty of resin and rolled while pressing in a flat surface on top of a piece of wax paper. To remove the excess resin I then wiped the excess from the wax paper and then fron the tube using a paper tissue. After it dried I applied a light coat of CA on the inside to seal the paper.
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RE: Extra 300 50cc scratchbuilt
Stab sheeting progress. After I glued all the ribs and started the sheeting I decided to lighten up the ribs (kind of dumb) but with a rotozip whip and a steady hand I cut them without damaging anything else nearby.
I can't post all he pictures at once because the sizes get all distorted since the new changes to the RCU servers. But I found that if you post one and then edit the post and add the other they don't get distorted. Kind of tedious but it works for the cause.
I can't post all he pictures at once because the sizes get all distorted since the new changes to the RCU servers. But I found that if you post one and then edit the post and add the other they don't get distorted. Kind of tedious but it works for the cause.