Arnold Atkins Posted January 24, 2020 Share Posted January 24, 2020 Hi Bill, Small world... I am in process of doing all the final checking and testing prior to the maiden flight this coming Saturday / Sunday (weather permitting - it is supposed to rain). I am not expecting any real issues and I am shooting for a CG in the 115 - 125mm from LE range. I ordered the longer carbon fiber legs (170mm height) and found out China is doing their 2 week New Years Holiday. So, that will not be here anytime soon (two to three weeks --- ARG!). The Maiden Battery will be a 6S 3400mah 75C unit and I have modified the battery platform to allow the pack to be more rearward if needed. The 1/2 throttle test gave me a 12 minute run time (full cycle). The 3/4 throttle test gave me a 9 minute full cycle run time. Power system: 5065-400KV (.60) outrunner, 80A Opto esc, remote uBEC, 3 blade 14x7 Windsor prop and a 3.25" aluminum spinner sanded, primed and painted to match. For the maiden flight I be using larger wheels/ tires without the wheel pants to gain a little nose height / prop clearance. Stay tuned for the Maiden report... <Arnold> Quote Link to comment Share on other sites More sharing options...
Bill Foster Posted January 24, 2020 Share Posted January 24, 2020 Hi Arnold, I was hoping you would see that I came back to this thread....nice to see some more action here. With regard to the question from Dennis, about how we get the weight of this model to 8.5 lbs ...could be a couple of things; the original weight listed was "fudged", and some of these 6S lipos weigh a pound or more themselves, and lastly, I'm guilty of this, some of us "build heavy"..! I have torn off too many landing gear blocks that it's usually the first thing I look at with a new model, and most require some additional beef to survive my grass field landings. It's so easy to do BEFORE you tear the gear loose..! Bill Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 25, 2020 Share Posted January 25, 2020 Mine is built pretty light so far. Only additions are the cockpit mods and a spinner that weighs less than the heavy plastic OEM spinner. With the "Monster Power .60" and a 6S 3400mah battery, I am still struggling to get the CG back far enough (I am currently at 110mm and want it back to about 120 - 125mm. It is starting to look like the battery will be almost directly ON or BEHIND the CG where the RX is / was supposed to be. I may even have to turn the elevator and rudder servos around so the horns are to the rear to make more room. I am trying hard to not add tail weight in the rear "battery area". On TR-1 (Turbo Raven - 1) I had to add a bunch of lead in the tail to get close to the "145mm" mark. I think I wound up around 120mm. and went with that. I do not like adding dead weight. Todays task will be to modify the "RX" area to facilitate the battery and a hold down system. Looks like RX relocation and reroute the wiring as well. My goal is to get to the 120 - 125mm CG without adding any weight in the tail Interesting project. Seagull kind of missed the whole concept of the Turbo Raven. Wayne's TR was truly a 3D aircraft. Light and SUPER powerful. I do not believe this model was designed with electric flight in mind at all. Otherwise they would have put 3 servos back near the tail with short linkages and moved the battery area to the center of the airframe. IMHO... . I may have to do just that before I am done. Ultimately I will probably replace the heavy wing tube with a carbon version as well. Just extra weight. <Arnold> Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 28, 2020 Share Posted January 28, 2020 OK, After making a battery tray that connects the center servo plate and the rear servo plate, the 6S 3400mah battery is now securely strapped into the area just in front of the rudder and elevator servos. Now, if I need to add any weight to the rear compartment, it will be minimal. The current weight with battery is now 7 lbs and 6 oz. With the heavy aluminum main gear legs being being replaced with much lighter Carbon fiber and the heavy aluminum wing tube also being replaced with carbon fiber, I just might get this bird down to 7 LBS or even slightly less. Moving and adding one servo under the tail would actually have added the weight of one additional servo. SO for the time being, I am going with the battery tray modification. I cannot understand how anyone can get this airframe to balance at the 145 - 135mm cg location without adding a ton of weight in the tail. Mine is built pretty much according to the manual and she came in massively nose heavy. Now, if I can figure out how to post pictures in this thread I will do so... <Arnold> Quote Link to comment Share on other sites More sharing options...
Bill Foster Posted January 28, 2020 Share Posted January 28, 2020 Good point Arnold ..."how DO YOU post pictures on this thread..???????" I thought it would be elementry, but No, I don't see the way to do this, so give us the steps, please..! Bill Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 29, 2020 Share Posted January 29, 2020 Hi Bill, Maybe we have to ask the folks that I had to ask to join the site.... There is a "image button", but it is NOT simplistic. It looks like they do not want any pictures posted. Maybe they are limited on forum storage. I can always just sent you a couple shots via email. After doing a lot more work, I finally got her back on the balancer and found she was STILL nose heavy at the 125mm CG location. I added a 3 oz. fishing weight wrapped in soft foam in the "rear battery hatch" and this brought the CG to exactly 125mm. The 3400MAH 6S battery is now as far back as it can go without moving the servos to the tail area. All up weight is now 7 lbs and 9 oz. Earlier in this forum, someone stated the wing tube is a good plane to start the CG at. The center of the wing tube is almost exactly on the 125mm from LE location. Maybe Seagull meant 125mm rather than 145mm. The 145mm from L.E. (Leading Edge) at the root looks pretty far aft to me. I may go find the CG and Center of Pressure calculator (on line) and plug in the numbers. It calculated the CG based on wing shape and includes the tail feathers. The Center of Pressure (center of lift) does not include the tail feathers and is based only on the main wing. The good news is that I can always change the weight in the tail and I do not see myself trying to get all the way to 145mm. I am tempted to start at 120mm from LE. I ordered the carbon fiber mains and the carbon fiber wing tube... Someday I will get them (slow boat from China mode shipping). Edited By Arnold Atkins on 29/01/2020 19:06:33 Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted January 29, 2020 Share Posted January 29, 2020 Posted by Arnold Atkins on 29/01/2020 19:03:12: Hi Bill, Maybe we have to ask the folks that I had to ask to join the site.... There is a "image button", but it is NOT simplistic. It looks like they do not want any pictures posted. Maybe they are limited on forum storage. I can always just sent you a couple shots via email. Arnold Sign in, and click on Albums on the top line. Create and name a new album You have to put your photos into this Albumn By adding photos, then SAVE Photos are added to your comments/posts from this album There is no real limit to the number correctly downloaded Quote Link to comment Share on other sites More sharing options...
Bill Foster Posted January 30, 2020 Share Posted January 30, 2020 Arnold, When I ordered my "tall CF gear" from China, I waited about 45 days and then submitted a complaint with the Paypal people (since I had used them for payment) Paypal went to bat, lodged my complaint, and "bingo", about a week or ten days later the gear showed up. I could not tell whether I got the original shipment or a second shipment; but I was impressed that PP got results for me. I'd be interested in getting a link from you for the CF wing tube. Also I'll try opening an "Album" here and drop some pics into it, and see what happens. Sounds like once you have pics in the Album you can source them when you need to include one or more in a post. Bill Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 30, 2020 Share Posted January 30, 2020 Testing the waters.... These are obviously not of a Turbo Raven. But they are JPG format... <Arnold> Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 30, 2020 Share Posted January 30, 2020 Yippie, It worked... !! Now to convert a few IOS format Turbo Raven pictures... Stay tuned for updates... <Arnold> Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 30, 2020 Share Posted January 30, 2020 duplicate... Edited By Arnold Atkins on 30/01/2020 19:23:50 Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 30, 2020 Share Posted January 30, 2020 How do you delete posts?? Edited By Arnold Atkins on 30/01/2020 19:24:30 Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 30, 2020 Share Posted January 30, 2020 Anyone? I do not see a delete post function anywhere. <a> Edited By Arnold Atkins on 30/01/2020 19:26:21 Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted January 30, 2020 Share Posted January 30, 2020 Arnold For 30 minutes, you will see EDIT next to the Date of your post You have 30 minutes to change your mind Quote Link to comment Share on other sites More sharing options...
Bill Foster Posted January 30, 2020 Share Posted January 30, 2020 Ok..my turn to test..I created my "Album" ..put some pics in it ..and now for the "test".. Speaking of "l-o-n-g slender legs" ..check out this set..! Bill Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 31, 2020 Share Posted January 31, 2020 Nice... Are these the 170mm tall extra 260 26cc / 30cc legs? Once you put the tailwheel on the angle is less steep. Sorry guys about the multiple posts. I didn't think it registered pushing the "post reply" so I hit it again...still no response so one more time.. I should learn patients... . Been working in yard ALL day so not much happening (except pushing a button too many times)... We got to 72 degrees F today... WONDERFUL. Got to love California. My Turbo Raven is now balanced exactly on the center of the wing tube... and as I measure, it is 125mm from the leading edge. Mine is still under 8 lbs. (barely). I am hoping the light main gear will take off a few ounces. Those stock legs are heavy (but strong). Later today I will take pictures of what I did to move the CG AFT without adding a ton of weight... <A> Edited By Arnold Atkins on 31/01/2020 01:07:04 Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 31, 2020 Share Posted January 31, 2020 OK, I finally have some time to play.... This is a picture of the mod made to support the new battery platform. It is piece of 1/4 x 1/4 hardwood stock epoxied in the corners and drilled for the forward mounting screws. Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 31, 2020 Share Posted January 31, 2020 This is a picture of the mod made to the rear servo plate that screws in via two 4mm screws. Edited By Arnold Atkins on 31/01/2020 21:07:22 Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 31, 2020 Share Posted January 31, 2020 This what it looks like altogether and ready for a battery. Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 31, 2020 Share Posted January 31, 2020 Now with the battery strapped in. I used TWO battery straps. The front Battery tray is completely empty. With this modification, she STILL needs about 3 oz. in the rear hatch to bring her to a CG of 125mm from LE. Quote Link to comment Share on other sites More sharing options...
Arnold Atkins Posted January 31, 2020 Share Posted January 31, 2020 Now a picture of where I am with her... Still awaiting the Carbon fiber parts. But she will be flown (maiden flight before those arrive probably). Quote Link to comment Share on other sites More sharing options...
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