John Slade Posted October 15, 2003 Share Posted October 15, 2003 I want to weigh my plane in various configurations of fuel and passenger loading. Does anyone know where you can get inexpensive scales that go up to 600lbs or so? Quote I can be reached on the "other" forum http://canardaviationforum.dmt.net Link to comment Share on other sites More sharing options...
chuckthedog Posted October 15, 2003 Share Posted October 15, 2003 John I bought a pair of 1,000 pounds, each last year to weigh my bird. I paid $ 250.00 each for them they are about 18 inches square, and about 1.5 inches high, digital read out either battery or AC. I would either sell or rent them to you. They weigh about 52lbs total. I don't know how much it would cost to ship. Shipped to me on UPS ground. Make me an offer. I live just south of Indianapolis. Quote If the phone don't ring. It's me Link to comment Share on other sites More sharing options...
Jim Sower Posted October 15, 2003 Share Posted October 15, 2003 What I've seen most commonly is a lever device consisting of angle iron welded together (ain't you glad you have that TIG machine) in such a way as to have support at one end, scale at the other and the weight of the airplane more or less precisely in the middle. A digital bathroom scale will then give you up to 600 lbs at 1# granularity with whatever accuracy it has (which I would guess is about +,-1%). I guess that's accurate enough, particularly since errors in the instrument would be consistant across the weight range that's important to us. I have been looking for an accurate balance scale less than 3' tall and come up empty so far. I can give you details of what I've seen if you like. Quote ...Destiny's Plaything... Link to comment Share on other sites More sharing options...
John Slade Posted October 15, 2003 Author Share Posted October 15, 2003 Chuck, It's avionics time, so renting would be better. How about $50, and I pay round trip shipping? It would be $50 you didnt have yesterday. John Quote I can be reached on the "other" forum http://canardaviationforum.dmt.net Link to comment Share on other sites More sharing options...
chuckthedog Posted October 15, 2003 Share Posted October 15, 2003 OK e-mail me adunsmore123@cs.com to exchange info. Quote If the phone don't ring. It's me Link to comment Share on other sites More sharing options...
Jim Sower Posted October 15, 2003 Share Posted October 15, 2003 Chuck, I'd be interested in renting them too. Perhaps after John's done with them. You might have a nice little business starting here. Quote ...Destiny's Plaything... Link to comment Share on other sites More sharing options...
chuckthedog Posted October 15, 2003 Share Posted October 15, 2003 Jim, you are welcome. Quote If the phone don't ring. It's me Link to comment Share on other sites More sharing options...
marbleturtle Posted October 16, 2003 Share Posted October 16, 2003 I run 80 miles up and down I-75 every day. Every day I see a commercial enforcement vehicle with the scales out and some poor truck driver loosing $0.50 a minute while an officer gets his paperwork in order. They're not always paying real close attention... I wonder how accurate those scales are. Quote This ain't rocket surgery! Link to comment Share on other sites More sharing options...
chuckthedog Posted October 16, 2003 Share Posted October 16, 2003 Turtle, The ones I rented john are good to ounces. If you are talking about the ones Deisel Dan is using. He will show you a calabration tag that will stand up in his state trafic court. States love over weight trucks almost as much as transporting fuel in a trailer without a tanker or haz mat endorsment. Quote If the phone don't ring. It's me Link to comment Share on other sites More sharing options...
Norm M Posted October 16, 2003 Share Posted October 16, 2003 I have a set of stock car scales. www.performancebodies.com In fact, they are getting drug out this weekend for max gross weight flying tests. I brought them to Oshkosh last year in case anyone wanted to play liers poker with airplane weights, but it didn't work out to use them. Maybe next year. So far, have weighed 3 Cozys, 1 Long EZ, 1 RV6, one Mustang II, and a 172. Easy to use, but a bit pricey. For max weight testing we load the plane while it is sitting on the scales. You know exactly where the weight is and how much. Regards- Norm Quote Link to comment Share on other sites More sharing options...
John Slade Posted October 30, 2003 Author Share Posted October 30, 2003 Norm, What did you're Cozy weigh in at? I received Chuck's scales and got an initial weight of 1210 lb with everything except the intake and a couple of pipes. No oil or water. Then I made a list of all the "extras" I'd installed including the turbo, intercooler, upholstery, leather seats, air conditioning, electric nose lift, electric speed brake, etc. etc. etc. If I deduct the weight of all this lot I get down to 1049 lbs. Of course I'm not going to take all these things out, but it looks like I built a light airframe before I started adding all the luxuries. Makes me feel better. I'm still 100 lb ahead of Wayne I haven't done the balance part yet. Quote I can be reached on the "other" forum http://canardaviationforum.dmt.net Link to comment Share on other sites More sharing options...
Norm M Posted October 30, 2003 Share Posted October 30, 2003 My Cozy came in at 1197 pounds. Here is a list of what is included: Standard airframe, with long canard, all armrests, seat belts, seats IO360A3B6D with dual electronic ignition, B&C 40A alternator plus SD8 alternator, B&C starter, 13 row oil cooler, Airflow Performance (high pressure) boost pump, oil to the 5 quart line, unusable fuel 8 inch extension, 2 blade Sensinich wood prop 17Ah Odyssey battery, mounted in hell hole on front side of firewall Wilhelmson electric noselift, electric belly board, Strong pitch trim RMI uMonitor, RMI uEncoder, King xPonder, Icom Comm, PSE audio panel, Garmin 295 GPS, dual fuel guage, Alt, ASI, Navaid A/P, RCA elec AH CG came out at 111.9 (If I remember correctly) Things that are not included: Upholstery (it looks like the leather seats are going to weigh 8 pounds each, so add about 32 pounds). Wheelpants, spinner So, here's how I figure it. If I had used an 0360- save 35 pounds No noselift- save 10 pounds Cleveland 6 inch wheels, brakes, tires save 15 pounds Shorter canard- save a couple pounds plastic peel ply, 5% save 60 pounds MSG epoxy, 5% save 60 pounds I used 100% peel ply- could have saved 5% save 60 pounds Finishing- excessive paint & primer certainly save 20 pounds Hydraulic crimped hoses for oil & fuel save 5 pounds So, if I would have followed everyones advice, the plane could have weighed in at less than 940 pounds! Realistically, between the engine, noselift, and big wheels I probably have a 50 pound adder. There is probably another 10 pounds that could have been saved with a purchased set of arm rests and nose wheel cover. Better technique may have been able to save 10 pounds on filler, maybe 5 to 10 pounds on primer and paint? That primer and paint is heavy! So, maybe 1150 if I had used more conventional engine and wheels, and 1125 with improved technique. I'm satisfied with the weight. I still have better than 1000 fpm at 5000 ft climb rate with the plane ballasted to 2200 pounds. Next step is to get a better matching prop and trade that climb performance for speed! -Norm Regards- Norm Quote Link to comment Share on other sites More sharing options...
marbleturtle Posted October 30, 2003 Share Posted October 30, 2003 Hey John, Do you think your weight savings came from your "poor man's vacume bagging" technique? Quote This ain't rocket surgery! Link to comment Share on other sites More sharing options...
John Slade Posted October 30, 2003 Author Share Posted October 30, 2003 Partly, yes. That and the MSG epoxy. Notice Norm estimates that these two items saved him a total of 120lb. That's enough to make the difference between a light plane and a heavy one. Note: I misread Norm's message on this - He said he could have saved these amounts, not that he did. Quote I can be reached on the "other" forum http://canardaviationforum.dmt.net Link to comment Share on other sites More sharing options...
Marc Zeitlin Posted October 30, 2003 Share Posted October 30, 2003 Originally posted by John Slade Partly, yes. That and the MSG epoxy. Notice Norm estimates that these two items saved him a total of 120lb. That's enough to make the difference between a light plane and a heavy one. Norm's estimates (sorry Norm) aren't realistic. The fiberglass/foam/epoxy in total only weigh about 300 - 400 lb for the whole plane. The epoxy weighs maybe 100 lb of that. If you've only got 100 lb. of epoxy in the plane, please explain to me how you're EVER going to save 60 lb. by modifying your peel ply technique. Not gonna happen. Same with using MGS instead of something else. According to Norm's calculations, he'd have used zero epoxy if he had used MGS and modified his peel plying. Huh? Now, if he claims that he'd have saved 5% each on the EPOXY weight, or 10 lb. total, I could maybe believe that, but that's a far cry from 120 lb. Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
John Slade Posted October 30, 2003 Author Share Posted October 30, 2003 Yea, I'd agree with Marc somewhat on this, except that I think the savings might be as high as 20 % or even a bit more. It's significant, but its still not going to be 120lb. I think perhaps Norms numbers were a bit "tongue in cheek". A little dry sarcasm from the mid west, perhaps? How about it, Norm? Quote I can be reached on the "other" forum http://canardaviationforum.dmt.net Link to comment Share on other sites More sharing options...
Norm M Posted October 31, 2003 Share Posted October 31, 2003 <<I think perhaps Norms numbers were a bit "tongue in cheek". A little dry sarcasm from the mid west, perhaps? How about it, Norm?>> You know, this whole bunch is drier than some type of fart. (I can't remember what type.) Of course the 5% numbers are pure BS. It was an example of how these generalizations can be miscontstrued to result in significant weight savings. Marc is exactly right with the 300 to 400 pound number concept. I don't know what a realistic 'light' airplane weight truly is. I know mine is not it, because I have a heavy engine, heavy wheels, elec noselift, etc. Also, I know that the second time around I could do a better job in minimizing the weight in my layups and even more so in the finishing process. Early on I was so hung up on the weight issue (come on! if you read the plans and take them to heart, you have to be!). I turned the excessive brass off the fuel selector valve to try save an ounce. I have helped weigh a Long EZ (with a newly received show winning finnish) that tipped the scales at 1300 pounds. And it was not a fancy leather interior either. We have seen a lot of real world planes weigh in at 1200 to 1250 pounds. I have test flown my plane (which should not be compared to any other planes in the universe, & perhaps should be called something other than a Cozy just because I actually built it myself) with a CG of 96 back to a CG of 102. I have flown up to a gross weight of 2200 pounds (honest weight, sitting on the scales). 460 pounds in the front seat, plus maybe 16 pounds of fine leather seats. With the front mounted battery in place! I can honestly say that the performance is very acceptable at each of these boundaries. Now, I don't want to fly into the corner where it is heavy and forward CG, because that is asking a lot of the front lift, fork, and wheel. And I don't care to work towards the aft CG, because that's where the boogeyman lives. As far as expanding the envelope toward heavier, I believe the plane is capable of much more. I have flown other planes at gross, and they were very uncomfortable. I have seen other experimentals flown at gross, where the pilot emerged from the flight sweating and shaky. My plane is not even close to feeling like that at 2200 pounds. Do I need more than 1000 pounds of actual usable payload? I don't think so. The quest for the 1050 pound airplane may be noble. I chose to finish my airplane and fly it, and it works very well for that. Am I going to go out and win races? No. Is it going to be uber-efficient and set new fuel economy records? No. But it is going to haul me and my family, on my typical mission, with enough capacity for plenty of fuel and a reasonable amount of baggage. Saving another 100 pounds of weight on the airframe may have been nice, but not necessary. Regards- Norm Quote Link to comment Share on other sites More sharing options...
Norm M Posted October 31, 2003 Share Posted October 31, 2003 So how tacky is it to quote your own message? <<Marc is exactly right with the 300 to 400 pound number concept. I don't know what a realistic 'light' airplane weight truly is.>> If you look at the posted numbers, we see 1135, 1155, 1175, 1197, 1212 and 1258. The heavier numbers tend to have justification along the lines of dual batteries, electric noselifts, big tires, heavy engines, etc. I suspect that to get a plane down to 1100 pounds, you have to use a very light engine, and minimum equipment. Below that, you start weighing the plane before primer and paint, no seats, armrests, etc. Look at the Rutan planes in the museum at Oshkosh. Most of the planes that we fly have a better finish on them. So, the improvement in finish comes at a price. Most of us want some of the power accessories. -Norm Quote Link to comment Share on other sites More sharing options...
Wayne Hicks Posted October 31, 2003 Share Posted October 31, 2003 Rutan saved weight on the Voyager by not finishing/painting the bottom surfaces. ...Hicks Quote Wayne Hicks Cozy IV Plans #678 http://www.ez.org/pages/waynehicks Link to comment Share on other sites More sharing options...
Wayne Hicks Posted October 31, 2003 Share Posted October 31, 2003 ...and the dry farts? They're called SBD's. Silent But Deadly. Quote Wayne Hicks Cozy IV Plans #678 http://www.ez.org/pages/waynehicks Link to comment Share on other sites More sharing options...
Cozy1200 Posted October 31, 2003 Share Posted October 31, 2003 <<Rutan saved weight on the Voyager by not finishing/painting the bottom surfaces>> So how did he finish it and protect the fiberglass from UV? Quote Drew Chaplin (aka the Foam Whisperer) --- www.Cozy1200.com - I'm a builder now! --- Brace for impact... Link to comment Share on other sites More sharing options...
dust Posted October 31, 2003 Share Posted October 31, 2003 I believe it was a one mission plane epoxy/fiberglass/kevlar/carbon/boron fibers don't deteriate that fast he he he or we would have to paint As we build enjoy the build mike Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
Cozy1200 Posted October 31, 2003 Share Posted October 31, 2003 I guess that does make since. A few weeks exposed to UV probably did not affect the structure that much. Quote Drew Chaplin (aka the Foam Whisperer) --- www.Cozy1200.com - I'm a builder now! --- Brace for impact... Link to comment Share on other sites More sharing options...
Richard Schubert Posted November 1, 2003 Share Posted November 1, 2003 I think the correct phrase is "Drier than a popcorn fart":o Quote "We choose to do these things not because they are easy, but because they are hard." JFK Link to comment Share on other sites More sharing options...
Jim Sower Posted November 1, 2003 Share Posted November 1, 2003 <<Rutan saved weight on the Voyager by not finishing/painting the bottom surfaces>> <So how did he ... protect the fiberglass from UV?> By not exposing his belly and lower wing surfaces to the sun ... not flying inverted ... amy more than absolutely necessary Quote ...Destiny's Plaything... Link to comment Share on other sites More sharing options...
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