RE: fuel proof spray paints?
I was trying to paint a cowl a few years ago, and tried all the over the counter spray paints. Nothing worked. All started to peel and soften within a few days of flight. Finally I just painted it with the color I wanted. Once that paint had cured, I coated the entire thing with acetone thinned 30 minute epoxy. A little really went a long way. Applied the epoxy with a latex rubber glove and my finger. It gave the cowl a beautiful high gloss finish, the color hasn't faded, and paint hasn't softened or peeled in over three years. Brad
Posted on: 8/13/2012 10:53 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11191732

RE: What are the pitfalls using LIFE batteries??
I don't know if the cheaper chargers have changed, but there was a video last year that showed the difference between the Cell-pro and the other chargers. As long as the battery is healthy, it doesn't make much difference. But the Cell pro line has a charging algorithm that identifies severely out of balance conditions or very low voltage due to complete discharge and will recovery the battery as long as its not physically damaged. Most cheap chargers claim that capability, but tend to be less effective at it. I agree that I would like to have a little quicker access to the charging modes, particularly since I cycle between 1C or 3C LiPo and the A123 modes which essentially means beeping through the entire menu (Cell-Pro 4S). But its a small price to pay for a really effective charger. Brad
Posted on: 6/8/2012 3:22 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11110963

RE: What are the pitfalls using LIFE batteries??
I'm getting my information directly from the A123Systems website. http://info.a123systems.com/a123racing/ is a link to the following quote: Effective January 24th 2011, A123 Systems’ subsidiary, Enerland, no longer manufactures or sells RC products. Products sold under the brand names A123Racing, Enerland and PolyQuest have been discontinued. I have to admit, this information is old. Last year I was trying to find A123 batteries and nobody had them in stock, and A123Systems would only sell them in lots greater than 1000 units. Revolectrix listed them, but they were always out of stock. Same with other sources. Apparently they're making their way back into the market. I bought a 36V portable tool battery pack and cannibilized it to get 10 cells and made 5 2S 2300mah packs for $120. Now its hard to find a 2S 2300mah pack under $40. I am glad to see them showing up online again. Brad
Posted on: 6/6/2012 2:34 PM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11109096

RE: What are the pitfalls using LIFE batteries??
I've been using A123s in my 30% IMAC plane for three years. The pack still has nearly 100 percent capacity. The concerns about the discharge curve in my plane are not significant. My plane draws about 250 mah per flight (twice through the sequence). I did a discharge curve on the battery a couple years ago and found that while the curve is very flat through most of the discharge, as long as the initial voltage was above 6.3 volts (two cell pack), I still had 15 minutes of flight time before the voltage dropped below 6 volts. I normally recharge them every 4-5 flights anyway since they charge so quickly. The Cell Pro series of chargers is absolutely the best. Their software monitors each cell and it doesn't get fooled into a false full charge reading when one cell is done. The nanostructure of the A123s makes them much more durable than the other LiFe batteries, but genuine A123s are getting hard to find. A123 stopped their hobby line last year, and I'm not sure if they're still supplying to the hand tool market or not. They were trying to focus on car manufacturers and solar storage, but I think Chevrolet snubbed them and the company may be in trouble. Their battery is patented, so if it doesn't say A123, its just a LiFe battery. I don't think they've entered into any licensing agreements with other manufacturers. Brad
Posted on: 6/6/2012 3:28 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11108335

RE: A new rogue pilot with questions
95db at 25 feet is EASY for nearly any stock glow .46 with the stock muffler and a good prop. I have a DLE-55 gasser with a KS cannister that meets that. Heck, most .40 class glow motors can beat 90db at 25 feet (based on measurements we made a few years ago). Brad
Posted on: 5/31/2012 3:37 AM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=11100911

RE: Should the AMA consider changing FPV Ops 550.pdf
The only change I would make to the FPV guidelines would be removal of the weight/speed requirement. If the plane is operated IAW all other AMA rules, on a buddy box, within VLOS, the weight and speed restrictions add nothing. Brad
Posted on: 5/30/2012 11:59 AM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=11100141

RE: A New Event January 2013 any interest?
Your best bet would be to contact Tim Attaway, the Southwest Regional Director for IMAC. He can be reached at SWRD@mini-iac.com Brad
Posted on: 4/17/2012 7:10 PM by Author "bkdavy" in the forum "IMAC"
http://www.rcuniverse.com/forum/fb.asp?m=11046521

RE: yak 54 seagull help 63
[quote]??????????? If the back edge of the wing tube makes it neutral, then how could the front edge make it nose heavy? If yo move the balance point forward the plane balances tail heavy. [/quote] The aerodynamic center of lift is a constant based on the airfoils. It does not move. If you put the center of gravity of the plane coincident with that point, the plane is neutrally balanced. If the center of gravity falls behind that point, the plane is tail heavy and unstable. If the center of gravity is forward of that point, the plane is nose heavy and aerodynamically stable. For the airfoil on the seagull 54 yak (and in fact most aerobatic models) the center if lift is at the thickest point of the wing, which is also where the wing spar is normally located. If the balance point is on the forward edge of the spar, the plane will be slightly nose heavy becase the center of gravity (balance point) is forward of the center of lift. Brad
Posted on: 4/2/2012 5:29 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11024738

RE: yak 54 seagull help 63
If the tank is forward of the CG, then check it empty. A friend of mine had one. The correct CG, which Seagull Models has been told many times but refuses to change in their instructions, should be located between the front and back of the wing tube. I don't remember the specific measurement, but if you're in that range your safe. Back edge will be nearly neutral, front edge will make it nose heavy but stable. Brad
Posted on: 4/1/2012 5:32 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11023417

RE: Have questions on thunder tiger pro 46 need help new with gas motors
light white smoke with entrained oil is normal for glow engines. If you're seeing droplets, your engine is probably tuned very rich. Do a search on tuning here on RC universe or any other search engine. There are hundreds if not thousands of pages on tuning 2 stroke engines, and they all say the same thing. Brad
Posted on: 4/1/2012 5:28 AM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=11023408

RE: new speed brake idea ... what do u guys think ?
Aerodynamically, it can work, although if you use as much of the wing as depicted on the drawing, you'll probably just stall, spin and crash. Most of our models will slow down very well without additional mechanical mechanisms because they're very lightly loaded wings. Learn to use the elevator as a break to pull the nose up and reduce airspeed rather than diving at the runway, and you'll solve the speed problem on landing. Second observation, if you must use spoilers (they spoil the airflow over the top of the wing and reduce lift) you can usually just use a separate servo for each aileron and program your radio for "spoilerons". Third, to reduce speed without killing lift, you're better off using a flap on the bottom of the wing. This will not interrupt the airflow over the top, and prevents killing lift. Again, think about using a "flaperon" function on your radio to use the ailerons. If the plane is really large its possible to split the ailerons and use two servos on each side, so you can have separate flaps and ailerons. Brad
Posted on: 3/23/2012 10:02 AM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=11011960

RE: Decal paper for printer
Anything printed with an inkjet printer should be coated with a clear laquer spray before you apply it to your plane. Otherwise the first time you go to clean it, its going to run. I've tried finding waterproof inkjet inks, and was unsuccessful. If you can get access to a color laserjet, there are waterslide decal papers for laserjets, and you don't need to coat them. Work great. Brad
Posted on: 3/23/2012 3:23 AM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=11011603

RE: How did you spend Sat. 03-17-12?
Spent the morning working on a Club DLG project, then went flying. After breaking a prop, trip to the hobby shop, then back to mow the field for the first time this year. The evening was spent drilling and balancing the new props, and dealing with the neighbor that insists the planes are flying over her house (she's wrong - luckily our property owner likes the club, not her). Brad
Posted on: 3/18/2012 4:38 PM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=11005970

RE: TT 46 Pro maximum 8500RPM
You probably don't need to replace the connecting rod or wrist pin if they look clean, no cracks or dings. Piston liner, piston, and bearings should be all it takes. The wrist pin doesn't rotate very far during operation. And since the engine was running with the existing crank and connecting rod, they're probably fine. You're just trying to correct a low compression situation and possibly bad bearings. I use a torch to heat the case to get the bearings out. Just keep the torch further away from the case, keep the flame low, keep moving it around, and don't try to heat it rapidly. Or us the oven. I've never warped a case. Should you be careful? Sure. Just don't lose a lot of sleep over it. And in the future, you might want to consider the rebuild costs when purchasing a second hand engine with unknown history. Its a risk you take. But they're also fun to work on! :) Brad
Posted on: 3/9/2012 3:27 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10992612

RE: TT 46 Pro maximum 8500RPM
Go to http://www.tiger.com.tw/product/9141.html and download the pdf version of the manual. It has the exploded view of the engine and the carb, part numbers, and everything else you'll need. Given the performance issue, replacing the front and rear bearings, piston, and liner, the engine should run like new. I'm confident you probably don't have a problem with the carb or o-rings since you stated earlier that the engine transitioned well. Normally air leaks around o-rings or clogged high or low speed needles evidence themselves with transition problems. I seem to recall in past searches for parts that TTPro parts were harder to get here in the states, but I'm betting you can find them much easier down under. Good luck and let us know how it turns out. Brad
Posted on: 3/8/2012 3:32 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10991089

RE: TT 46 Pro maximum 8500RPM
You probably have a lot of varnish built up on the wrist pin that's preventing the connecting rod from moving back far enough. Put the piston and crank at bottom dead center to see if you are getting the connecting rod fully against the back side of the piston. To loosen the varnish, you can use some fuel to soak it and soften it. Also, you should get a little more play with the piston at bottom dead center rather than top dead center. It should slip right off the crank with the liner removed. And definitely remember to mark the back side of the piston and connecting rod if you're planning to reinstall them. Examine the connecting rod closely. I think the forward side has a small chamfer around the forward side of the big end (or was that OS?). Brad
Posted on: 3/7/2012 3:24 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10989701

RE: TT 46 Pro maximum 8500RPM
If the cylinder liner and piston can be replaced a half the cost, go for it. These engines are VERY simple design, easy to work on, and in the course of a few minutes labor, you learn a lot about your engine. TTPro 46 is not a cheap engine, its just inexpensive. Its a very reliable engine, and pretty hardy. I've had them completely underwater, and then had them running and ready to fly within a few minutes. Learning basic engine repair and maintenance in this hobby will save you a LOT of frustration and money in the long run. Brad
Posted on: 3/6/2012 2:28 PM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10989036

RE: TT 46 Pro maximum 8500RPM
My experience with the TTPro 46, and I've had a few - with that prop you should be getting at least 11k rpm. So you either have a mechanical failure (bad bearing), a worn cylinder (causing low compression once the engine warms up), or possibly a partially plugged fuel system. My money is on a worn cylinder/piston. These are ABN engines, so checking compression when the engine is cold is deceptive. The cylinder expands at the top as the engine heats up, leading to reduced compression. The good news is that the piston and cylinder can be replaced in a few minutes if you can find the parts (which are normally pretty easy to find). While you have it apart, carefully examine the bearings. Any sign of rust on the bearing, or indications that the cage is failing, replace them. Again a relatively easy job. If it were me, I'd probably just replace them anyway. After replacing the cylinder, piston, and bearings, you have a new TTPro 46. After rereading your post, you said if you lean the high end, the transition becomes rough andthe engine stalls. I suspect you haven't tuned the low end. After setting the high end to peak then backing off a little, you probably need to adjust the low end. That should fix your transition and deadsticking. After adjusting the low end, readjust the high end again. Then check low end again. Its a cyclic process, and there's tons of information posted about tuning. Brad
Posted on: 3/6/2012 3:31 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10988383

RE: RCU poor performance lately
At least its not the AMA's fault! :) Brad
Posted on: 3/6/2012 3:15 AM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10988375

RE: Mono-Kote Questions
For me the simplest most effective way to avoid bubbles in the finished job is to avoid using the covering iron as much as possible. Only use the covering iron at the edge of a piece of covering to adhere the edges. Don't slide the iron. Put it down on the covering and roll the iron over the edge, particularly at wingtips, leading edges, and any corners. Once the edges are all adhered, use the covering heat gun and shrink the covering to fit. Always blow the heat away from the nearest edges. When its all shrunk smooth, use a soft cloth while its still hot to press down and adhere the middle. Make sure everything is clean before you start. Watch Minnflyers videos on covering. He shows you how to pull and heat the covering over compound curves (seeing this video changed my life :) ) Work with the largest piece of covering you can, work back to front, bottom to top so your edges are less likely to peel. Did I mention watching the videos? Brad
Posted on: 2/29/2012 3:19 AM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10981113

RE: Life Battery Discharge Question
If you can find someone with a CellPro Charger from FMA (Revolectrix) it has an excellent ability to recover lithium chemistry batteries. It will go into a safety charge mode and slowly bring the cells up to where they can be charged. It also has an excellent balance algorithm. Brad
Posted on: 2/20/2012 9:02 AM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10967476

RE: Regulation passed the House
[quote]ORIGINAL: combatpigg KE, my point is as a toy airplane modeler and flyer I don't want to be associated with GPS or video camera controlled flight in any way, shape or form. It's too bad, but I think it's wise to see the potential for abuse and write this mode of model plane control off as going a step too far. The Academy does not have any built in obligation to promote it, either. [/quote] I have to disagree with you CP. Down that road lies ruin. Lets see: I don't want to be associated with : Free Flight Jets Aircraft over 11 lbs Aircraft larger than 70 inch wing span Aircraft under 4 lbs Fill in lots of different activities that individual choose not to participate in. There are many people that safely fly video cameras FPV within existing AMA guidelines, and do it safely everyday. AMA currently does not permit Autonomous flight under its existing safety guidelines, and isn't likely to condone it in the future. On the other hand, there are currently products in development using GPS to establish flight boundaries for planes to prevent them from flying off, which will be a good thing! Better to have the AMA as a whole establish guidelines or rules for how these activities can be safely conducted under the guise of Hobby rather than simply ban them as a whole and wait for people to go do it anyway. Brad
Posted on: 2/20/2012 8:52 AM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10967452

RE: Regulation passed the House
From a regulators perspective, the FAA probably will NOT develop any guidelines or other documents (approval or otherwise) for CBO status because of this statement: (b) STATUTORY CONSTRUCTION.—Nothing in this section shall be construed to limit the authority of the Administrator to pursue enforcement action against persons operating model aircraft who endanger the safety of the national airspace system. What that means is that if an individual does something stupid (fly's FPV around the Statue of Liberty perhaps?) the Administrator has the authority to purse action if the FAA determines that person endangered the safety of the national airspace system. No other rules, procedures, guidance, etc will be required and the FAA is not required to establish such. Any person can claim to be under a CBO, but if the FAA determines a specific act endangered, it won't matter what the individual claimed. And the FAA won't have to ruin it for the rest of us to take that action. Brad
Posted on: 2/16/2012 2:28 PM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10962057

RE: Regulation passed the House
Bill passed and signed by the President. Good job. We can now answer the infamous comma question on AC 91-57 (which takes precendence, FAA guideline or AMA safety code) and the AMA wins. We hobbyists have to continue to act responsibly. If someone doesn't behave responsibly, the FAA has the teeth to act if they choose. What Congress enacts, Congress can repeal. Brad
Posted on: 2/16/2012 10:16 AM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10961704

RE: Regulation passed the House
Now here's the hook. The law says the FAA may not promulgate rules or regulations regarding model aircraft, but there is also the "notwithstanding any other provision of law...". What that means is that the FAA can still propose regulations that will restrict our access to airspace by provisions that would require FAA certification, control, approval, certification etc. of ANY aircraft operated above (pick a level, say 500 ft AGL) or within (pick a distance, say 500 ft) of any occupied structure or populated area. Note this is provided as an example only. I can think of a hundred ways to argue against such a restriction, but the law does not prevent it. Such a regulation would still place a huge burden on us, so we can't rest yet. Brad
Posted on: 2/7/2012 3:29 AM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10947701

RE: Regulation passed the House
Committee report was agreed to in the Senate today by a vote of 75 to 20 (5 not voting). Next step should be Presidents signature. Interesting that the vote in the House on the committee report was pretty split along partison lines (Democrats mostly against), but an overwhelming majority in the Democrat controlled Senate. I suspect this legislation will further delay publication of the NPRM, as the FAA will have to reconcile the proposed rule against the legislation. For those that are interested, the version that was voted on is in the conferenc report, and can be located at http://www.gpo.gov/fdsys/pkg/CRPT-112hrpt381/pdf/CRPT-112hrpt381.pdf Brad
Posted on: 2/6/2012 6:57 PM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10947307

RE: Model airplanes over NYC bad idea.
http://www.cnn.com/video/?/video/offbeat/2012/02/01/pkg-moos-flying-people.cnn#/video/bestoftv/2012/02/02/tsr-brk-israel-could-attack-iran-this-spring.cnn Apparently they did it right - practiced at a safe location, got permission from (well not sure who, but they had a permit), flew in safe locations (used camera tricks to make it look more dramatic, but I suspect they never even got close to major landmarks). My only concern is that someone less responsible may try it without these precautions. Perhaps we should be playing up the positive aspects of what they did right, rather than panicking and worrying about the scope of AC 91-57. Brad
Posted on: 2/3/2012 3:36 AM by Author "bkdavy" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10941477

RE: CG Tuning
It has nothing to do with inverted. Turning with ailerons - bank one direction. To keep the nose from dropping, use opposite rudder. Brad
Posted on: 2/2/2012 2:39 PM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10940738

RE: CG Tuning
Personally, I don't like to mix rudder with anything, and can't see any reason to mix rudder with the ailerons. The aileron position is not constant during a turn in order to hold a particular bank angle. If the aileron angle isn't constant, then you're rudder is going to be changing. The amount of rudder needed to hold the nose will be dependent on so many other factors, that trying to mix it to only one surface is a waste of time. Learn to use the left stick by practicing. Forget mixing while you're learning. The easiest way to remember rudder in the turn is to move the left stick opposite the right stick. If you bank left, use right rudder, and vice-versa. But thats just a generalization. Remember, the small parkzone planes are not built for precision flying, so don't overthink it. Just fly it like you stole it and have fun. Brad
Posted on: 2/2/2012 3:31 AM by Author "bkdavy" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10939815

RE: cut engine on a transmitter
There is no mid-position for the choke lever, so trying to use a single servo to operate ignition and choke probably won't work. Brad
Posted on: 1/31/2012 2:00 PM by Author "bkdavy" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10937245