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ORIGINAL: Garthwood

Nice borders you have there.

Charles.

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ORIGINAL: Garthwood

Night Prowler......................very nice, you'll love the Burrito. I've had mine for about two -three years, my favorite to start up the season. But I'll love this profile any time. Just got back from the field 25 km wind, power, power, power. Requires throttle management. Landings on windy days is a bit more challenging, no wing rocks if throttle is kept up. See pictures on this thread.

Charles.

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ORIGINAL: karmann34

So, I'm reading through this thread and notice that it started out as the Burrito Rudder Check. Then, it looks like somwhere between post 241 and post 242 about two years are hasta la bye bye. The date goes from 08/2004 to 08/2006????
Oh well, the Burrito looks like a lot of fun.

Edit.
Looks like there were originally more Burrito threads that were all put together..
Thought I was missing something??? Burrito, burrito must get burrito

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ORIGINAL: karmann34

Oh yeah, thanks! Got two of those MOJO 60's from Mr Swanson last month while visiting the fine folks of Leipers Fork, Tenn. Should have had them both in the air by now, but work waits for no one... it seems.
Yep, flying this afternoon and tommorrow and Saturday, since it finally stopped raining around here. Wish we could pump some of it out west or up north.

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ORIGINAL: Railridr

Dick Bl asked about saving weight. I have been doing a lot of research trying to lighten up my airplanes. Here are a few things that I have come up with.

First I have to day that Paul puts together a great kit. With that said, I did replace a lot of the sticks and sheeting in the kit with lighter wood. I did not go overboard. I made sure that the main spars and the leading edge sheeting were good medium balsa, beyond that most of the sticks were replaced with contest balsa. If I were to do it again, I would make the trailing edge of the control surfaces medium balsa or I would use 1/4 x 3/8 contest balsa. I used contest balsa 1/4in sq on the trailing edge of the control surfaces and had to reinforce some areas with strips of carbon fiber. I got a bit ham fisted when I was covering the control surfaces and broke the trailing edge on a few of them. When I fixed them I used a strip of carbon fiber tape to reinforce the broken section. I weighed all the wood before I started and then weighed it all again after I substituted lighter wood. I saved about 4.5 ounces on just replacing wood.

I used Ultracote Lite for covering. Of all of the covering materials, it is just about the lightest thing that can safetly be used. It weighs about 1.15 ounces per square yard. For comparison, Monokote weighs about 2.2 ounces per square yard, and Transparent Monokote weighs about 1.8 ounces per square yard. I did think about using Nelson litefilm, and I e-mailed Mr. Swany about it. He thought it would be not be durable enough based on his past experience with it. I weighed all of the airplane parts before I covered and after I covered them. The weight of all the covering that I used on the airplane was about 2.6 ounces. I saved about 2.5 ounces by using ultracote lite. The weight of all my unassembled, but covered parts was about 20 ounces.

I used plastic sucker bulbs wherever I was using thin CA. I mostly used thin CA on this kit. The parts and joints fit together so well that thin CA is used in most places in this kit. By using the plastic sucker bulbs I was able to control the amount of CA that I was using with great precision. I figure that I was able to save some weight by being able to control how much CA I was using.

I am using a 400 Mah 5 cell Nimh Battery Pack in my Burrito. I know most people would shy away from this, but I have found that on a fully charged pack I can about 45 to 60 minutes of flying time, and usually have about 100 Mah left in the battery when I get home. If I want to fly more than 4 - 15 min flights, I field charge my battery after 3 flights. The key to using a small battery pack is keeping track of your flights and knowing your limits. This battery pack weighs 1.6 ounces. I saved 2 - 2.5 ounces by using this battery back.

I am using an aluminum spinner nut instead of a plastic spinner. A plastic 2 1/4in spinner for the average .40 sized engine weighs about 1.4 ounces. A spinner nut weighs about 0.7 ounces. I saved about 0.7 ounces by using an aluminum spinner nut.

I am using a 6 oz fuel tank. A lot of the folks at my field think I am running a 10 ounce tank. I usually fly for bout 15 mins a flight. They do not believe me when I tell them I have a 6 oz tank. The engine had a throttle and I use it a lot. A 6 oz fuel tank weighs about 1.4 ounces. a 8 oz fuel tank weighs about 1.8 ounces. I saved .4 ounces by using a smaller fuel tank.

I am using 2 1/4in wheels. in the past I have used 2 1/2in - 3in wheels in my .40 sized airplanes but realized how much they really weigh.
My old 2 1/2in Sullivan Skylight wheels weigh .7 ounces each. My old 2 1/2in Dubro treaded lightweight wheels weigh .8 ounces each. I have since discovered Dubro super light wheels. one of these 2 1/2in super light wheel weighs 0.33 ounces. I went one step further and used a 2 1/4in super light wheel. These 2 1/4in wheels weigh .28 ounces. 2 of them weigh .56 ounces. I saved 1 ounce by using smaller lighter wheels.

I am using a Mousse Can Pipe. The stock muffler for the Thunder Tiger .46 weighs 3.7 ounces. The mousse can pipe with the header, silicone coupler, zip ties, and mousse can weigh 3 ounces. I saved .7 ounces by using a Mousse can pipe... Plus I gained about a 1000 rpms when using a 11.5x4 APC. If you believe ThrustHP that is about an extra 1.5 lbs of static thrust.

If you add all that weight up it comes to about 12 ounces.. give or take an ounce.

To go further on this airplane I could have used a Thunder tiger .36. A TT36 with a MCP weighs about 11 ounces. A TT .46 with a MCP weighs about 15 ounces. I could save another 4 ounces by using a TT36.

A TT36 Drinks less fuel. I can now use a smaller fuel tank. A 4 oz fuel tank weighs about 1 ounce. A 6 ounce fuel tank weighs about 1.4 ounces. I could save another .4 ounces by using a smaller fuel tank.

Now that our airplane is so light I can get away with using smaller servos on the ailerons. Some HS-85BBMG would do nicely. HS-85BBMG servos weigh .77 each. The HS-422 servos that I am currently using on the ailerons weigh 1.6 ounces each. I could save 1.6 ounces by using smaller servos.

If we add all that up it comes to around another 6 ounces of weight that could be saved.

Think for a minute that if I had built this burrito without trying to save any weight, it would weigh around 4.5lbs. Building this burrito like I did, I was able to save 12 ounces. bringing me to 3.75 lbs. If I were to have gone further with saving weight I could have gotten this airplane down to 3.375 lbs. At 3.375 lbs This burrito would fly Awesome, and with a smaller engine it would hover really well.