New HK 75" 30cc Macchi C-205 Veltro
#56
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Progress is kind of stalled due to holidays and a 109 parallel build, however I received the HK 150mm struts and did a test fit:
Perfect length (provided the wells will be enlarged) for the 100mm wheels
Perfect length (provided the wells will be enlarged) for the 100mm wheels
#57
w1, thanks for the continued infor. I'm going to start on the Veltro next week, probably. I'm ordering some stuff from HK so I may order the 150mm struts. I'll probably be using Spring Air retracts.
#60
#62
Finally got started on the Macchi. Hung the RCGF32cc on it. Cowl had gotten squeezed in shipping, so I had to cut a ring out of thin plywood and epoxy to front of cowl. The gap between the cowl and spinner was a little large so this will reduce the gap. Next were the tail surfaces. I like the dual elevator servos but not with pull-pull cables, so I used metal rods in plastic tubes. Had to install a center support. Came out fine. Then installed pull-pull cable set up for the rudder. Then test fitted the wing, and discovered that the horizontal stabilizers and wing are not parallel. I should have checked before installing tail feathers. I'm going to set up a type of jig and see if with careful use of the heat gun I can move things slightly and get lined up properly. I have WingSpan Electric retracts and Robart struts so the gear should not be too much problem. I have ordered a 5" spinner and a Jtech pitts muffler. I can see its going to take some mods to ensure sufficient engine cooling. Took some pictures but haven't loaded to computer yet. I'll send later. I'm not doing much in the way of mods. I am trying to build as light as possible, but I do plan on painting after the test flight.
#64
Here is the front of cowl showing cracks. The ply rig I cut. The engine mounted. I tried the heat gun procedure and got the horizontal stabs close enough. Also the elevator control rods and rudder pull-pull set up. Next is to start working on the wings. All control surfaces will have real hinges and not the CA hinges. I've had a number of the tear loose. Only one was not caught on the ground.
#65
It will take some careful mods to ensure engine cooling with the inline cowl. The head is out side the cowl but will need more cooling inside. The front of the tropical filter on the cowl is far enough forward that I can make it into a scoop to duct cool air to the carb area to help prevent vapor lock because of heat from a pitts muffler. Also there are some small scoops in the front top of cowl that I will enlarge. May add a small chin scoop right behind the spinner on the bottom and an air dam in front of exhaust cut outs for the pitts to help draw out the hot air. It seems that this plane will be fairly light for a warbird this size so the wing loading should not be too much and should fly good. We will see. I've ordered a 5" aluminum spinner and a Jtech pitts muffler. I already have some WingSpan 90 degree electric retracts and Robart struts. I will need to order a pilot. Calculated scale is 1/5.5. So do I go 1/6 scale or 1/5 scale for the pilot?
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1:5 pilot is easier to find but take some measurements before ordering to make sure it'll fit
Where is the tailwheel supported? I thought it would be necessary to cut out a hatch and build a former for it?
I'll post a few pics with engine cooling mods from other similar planes
Where is the tailwheel supported? I thought it would be necessary to cut out a hatch and build a former for it?
I'll post a few pics with engine cooling mods from other similar planes
#67
w1, I used the tail wheel wire that came with the kit. I drilled a hole and the rudder base and on the bottom. Got it fairly straight. Then enlarged hole an install a nylon tube so the tail wheel wire wouldn't be wearing out the hole in the fiberglass. Hardest part was binding the wire 90 degrees to go into the rudder. I know, I could have cut off the bottom rear of fuselage and built and installed internal linkage for tail surfaces and tail wheel etc, but not into doing that much work on this plane. I got the 5" spinner. An aluminum spinner from MPI. It really is not quite the right profile. After I ordered it I found a carbon 3 blade 5" spinner at Troy Built for $59. I might be better and is $20 less. Oh well, that's the way it goes. Also I found my struts I thought I was going to use won't work. Will only take a 3.5" wheel. They are forked. I want to use a minimum of a 4" wheel. I can enlarge the wheel well for at least a 4" wheel, maybe 4.25" or 4.5". This will require angling the gear forward some but should work out.
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So the tailwheel is supported on the rudder. Make sure to check it regularly, and be very light on the tail.
How about the 5" P-51 Top Flite spinner that was suggested in earlier post (page 2)?
How about the 5" P-51 Top Flite spinner that was suggested in earlier post (page 2)?
#69
1w, I have a wheel collar bearing in the bottom of the nylon tube to take most of the load. The P-51 spinner might work especially for the 205. However, I think I will cut off the chin protrusions and make mine a 202, so the more pointed spinner will be more appropriate.
#71
I've been working on the Macchi for the last two days. Ailerons and flaps installed and linkages done. Landing gear installed sort of. My forked gear will only take 3.75" wheels. I really wanted to use 4". Cut them off as short as possible. The plug for the springs is now at the very top of the strut. They will just fit. I then put on the cg machine to see where I was going to put other equipment to get proper cg. Used 26% if cord, measured on wing just before in flair forward near fuselage. 3.25 to 3.5 inches back. To my surprise, it was tail heavy until every thing was put forward including the batteries, but it will balance without having to add dead weight. Speaking of weight, with all equipment placed and taped on plane, total weight was 13.7 lbs. Not too bad for a warbird this size. Still left to do is installing and connecting ignition system and fuel system. also more work to do on landing gear mounts. Here are some pictures so far.
#73
I've been working on the plane for the last few days. Got the ignition system and fuel systems done and the gear installed. The 5" spinner I have is too large. Going to try a 4.5" spinner. I've added a scoop below the prop and opened up every thing I can for cooling. Still waiting on a JTech Muffler. Ordered two weeks ago. Here are some pictures so far.
#75
w1, here a picture of the cowling.Site is not working right so I'll post more later. I've opened up and put baffle in the "tropical air intake" and made duct to mate to direct air to the carb. I've had vapor lock problems with rear carbs over a pitts muffler in a tight cowl, o this is to help the carb stay cooler. The full scale had to small scoops just under the spinner, so I added one for additional air flow to the cylinder. Also full scale had air intake in front of exhaust pipes so I opened them up to inside of cowl. I also opened up the two small scoops to top and made bigger than scale. I'm going to a smaller spinner , 4.5" ordered today, so I can drill small holes around the circumference of the cowl ring for additional cooling air and won't destroy looks of cowling. I gave up on JTech. Found out the order never processed on their web site. Found a better more compact pitts type muffler at Magnum RC so ordered one. Also an Xoar 3 blade 17-8 prop. I have one on a DLE 30 and works great so should be ok for the RCGF 32. I will cut cooling air exit at bottom rear of cowl and add air dam/cowl flaps to help air out. Not sure about internal baffling yet. Have to wait fro muffler.