hey guys, i'm a new-b to this hobby and just finished building my Spadet LC-40 trainer aircraft.
i just got a brand new TT .46 Pro last night and have a few questions...first, i found that the directions for the break in aren't that great, and am wondering how to break in the engine the right way....with the engine, i have a du-bro 2" spinner, 2 11x7 and 1 10x6 MAS props (this is what a friend told me to buy. the 11x7's are for the break-in and the 10x6 is for added speed later on....this is what he told me..), and a Fox RC Long 1.5V bar glo plug....also i need to know what type of fuel to use...

You should use 10% nitro fuel. How to break in? Read the manual. You can get a good answer there.

The TT46 is an easy to use engine, will run happily on an OS No. 8 with 15% nitro. Props for the trainer would be an 11x6, I would not bother with the 11x7 as there is no need for so much speed on your trainer. The 10x6 is for speed (about 13.5K RPM) and enjoy that on some fast plane. You can run on 5% nitro also for a trainer and does not really matter if you go 100% synthetic (Cool Power), semi synthetic (Omega) or full castor. I use Cool Power 15% heli fuel, works great as I hate castor on my planes.

Breaking in is always an issue (different people will say different things), what a lot of flyers here will normally do is to run her a little rich (about 3.5 turns out) at say about 50% throttle for about 2 tanks, tune her and then just fly. When you fly her let it be on the rich side, maybe say 500-600 RPM off the peak. Take it easy for the next few tanks. This engine might not be fussy but it does not like to be abused, don't run her too lean, once it heats up a little too much it will lose power.

My TT46 starts with a back flip and is totally reliable, great value for money.

You will find that manuals do not make much sense. Just run a couple tank fulls through it while adjusting it and fly it. Anybody around to help you?

Run rich for a few tanks before you start leaning it out.

You have the props backward -- the 10-6 should be used for break-in (to keep the load minimized). The 11-7's are actually too much prop for best performance from a 46 (even a TT Pro) -- they are 60-size props. You certainly should NOT use them for break-in. 11-5 & 11-6 are good choices, & if you want speed, a 10-7 will do nicely.

Most sport engines (including the TT Pro) work very well on 10% nitro -- you won't be able to tell any difference with 15% , it costs more & it will shorten your glo-plug life.

The TT 46 Pro really runs well on OS #3 plugs, & OS #8 plugs. The idle-bar plug is totally unnecessary with that engine -- it idles dead smoothly & picks up instantly. I find that its performance actually falls with an idle-bar plug.

ok. im the only one im my family thats into this hobby and sofar, i have been on my own (im 14 and my dad is re covering the wings on our full-size Piper cub, so not much help from him....my mom, well she doesn't really know much about this kinda stuff so.....) there has been 1 guy from the club who has helped me quite a bit (the friend i talked about earlier)....but i wanted to get a few other peoples opinions....and no, this manual doesn't say much....

Also, how do these things run in the cold? im talking like -5 degrees celcius...
and thanks britbrat, ill do what you said about the props....this is exactly the kinda answers im looking for

Glow engines will run well at -5 degrees C. But getting them started can be difficult. Once running, they run OK. You should buy a 12V battery (like a motorcycle battery or a small 12V lead-acid gel cell battery from the hobby shop) and a starter. This will make your hobby more enjoyable. Glow engines will sometimes start by flipping, but on some days the 12 V starter is the way to go.

I'll second britbrats advice. It was filled with good solid information.

Britbrat hinted at using an OS #8 or A3, but I'll go ahead and insist that you start out with one of those two plugs. They make the TT Pro 46 run far better than it ever will with a Fox plug. (The manual that came with my TT Pro 46 specifically warns against using Fox plugs.)

The Thunder Tiger factory is notorious for their loosely assembled engines, which can sometimes cause problems getting them to run right. But after everything is tightened up, every Thunder Tiger I've ever seen runs like a dream.

Therefore you'll need to spend a few minutes tightening EVERY bolt, nut, and screw on that engine before you ever run it. If you don't, then your engine will develop pressure and vaccuum leaks that will drive you nuts when trying to tune it. Tighten the head, backplate, the fuel nipple on the carb, and the throttle barrel retaining screw on the carb. Then loosen the draw-bolt that holds the carb to the crankcase, push the carb into the crankcase until the O-ring compresses, and tighten the mounting bolt making sure the O-ring stays compressed.


At temps around -5 celcius, the OS #8 or OS #A3 will become even more important for easy starting and reliable operation. But once it's running correctly, the cold weather won't cause any problems at all. In fact, these glow engines actually run better in cold conditions than in hot conditions.

ok thanks alot dave, and all u others...i really appreciate all your help. im going to order an OS #8 plug, and am probably going to go with 5% nitro fuel that has 20% castor/synthetic blend (as the manual strongly recomends). as for the break in, ill run it rich for a coupple of tanks then fly it a little rich as well for a while, as you guys seem to be saying. anymore tips, tricks and suggestions would still be appreciated.

Thanks again,
C. Grant

oh, btw, for the radio setup, is up elevator achieved by pushing/pulling the right stick back or forward? (just wanted to know if its the same as full-size where for up elevator, you pull back on the stick.)

I own several of these engines. All run fantastic. However, as with any engine it will take a little tuning time to get them in the sweet spot. My favorite prop for these is the APC 11x4. Works great for 3d planes and works great for trainers. 10x6 is great for break in but I ran through a set of bearing with this prop. It spins extremely fast, makes a lot of noise, and not as much thrust as a 11 inch prop. 11x4 will get you off the ground fast, act as a brake for landing, and not overspeed the plane which is helpful in training. 11x5 is a second choice and will quiet the plane down a little further. I use thunderbolt 4stroke plugs which are about the equivelant of the os#8. They used to be called 2/4 stroke plugs but now they are renamed. You can get them from hobbypeople.com and the best part is that they are only $2.95 compared to the $6 os equivelant. They work great in all my engines all the way up to my 23cc Super Tiger. I've had them last several seasons with no problems. Always a single backflip to start the engines once tuned properly. USE A LEATHER GLOVE with this method for safety. An APC prop can chop your finger off without a hesitation.

As far as cold running I don't suggest it in your case. Bad for the break in. Head temps won't stay hot at lower throttle settings. This will give you fits trying to tune the low end not to mention with the head cold you will prematurely wear the fit between piston and sleeve on the abc engine.

ok thanks. all this info is great!!

Keep in mind that the TT Pro 46 uses ABN/ABC (aluminum, brass, nickel or chrome) technology. That means it doesn't have a ring, and relies on thermal expansion to achieve the proper clearances between the piston and cylinder. If you run an ABN/ABC engine too rich, it never gets up to operating temperature and can wear out the piston prematurely. An ABN/ABC type engine should be broken in by running on the rich side, but not so rich that it misfires every other stroke. Because of the thermal expansion required for proper break-in, running too rich in -5 C temperatures is even more risky. (I strongly suspect this is what spyder0069 was referring to.)


Yes. Pull for up elevator.

C. Grant -- you're getting good stuff here -- nothing out of step at all.

If you do run an 11-4, you will have to practice throttle management in level flight -- it will turn at over 15,000 RPM, on the level, in flight on a trainer. Pretty fast. It will also most likely give you unlimited vertical capability, or very close to it , & VERY short take-off runs -- usefull stuff.

C. Grant - you briefly mentioned friends and clubs. Please be sure to get with an experienced RC instructor. Your plane will last a lot longer and you will have a lot more fun. This may already be your intention but I wasn't sure.

Good flying!

ok thanks guys. im mounting the engine now but i just realized that before i screw it in, i should run the throttle pushrod and fuel lines....do these run through the firewall?

To reiterate the advice on the rich setting - an ABN/ABC engine needs to be brought up to temperature quickly. The way I broke my TT Pro 46 in was to start it, run the throttle to max and then peak using the high speed needle. With the 10x6 you should see around 14000 RPM. Thats good. back it off about 300-500 rpm by richening the high speed needle a few clicks, let it run for about 30 seconds, then shut it down. Let it cool completely (15-20 minutes), then start it again. You shouldn't need to adjust the high speed needle at this point. Let it run for a tank. Now go fly.

I followed this procedure and my TT Pro 46 has been a VERY sweet running engine. After about 5 tanks, I had to make some minor adjustments to the low speed needle (2 years ago) and haven't had to touch it since. I found the best prop was an 11x5 (optimum for thrust and speed on a trainer type plane). I'm now moving the engine to my new GP CAP 232 .40.

Brad

Are the tank and throttle servo inside the fuselage of the Spadet LC-40 trainer aircraft? I'm not familiar with that plane. If you have plans/instructions they should indicate what to do. If inside, Yes would most likely be the answer. Is there a place online where we can see info on the plane?

OK, found it myself. Just so everyone knows the plane, here it is:
http://www.spadtothebone.com/SPAD/Spadet/

Definitely go thru the firewall. Determine the engine and mount locations and then choose a routing for the fuel line and throttle linkage.


BTW - not trying to chase you away but there is a SPAD forum with some very experienced people there on SPADs. People here are more into balsa but not exclusively. This is, of course, just my opinion.

thanks. im going to go hook up the fuel lines and throttle linkage now. thanks for the info

done!! lol anyways i still have to fasen the tank down but i want to know what i should use....im thinking of using either doubble sidded tape or high strength vel-crow.....

Neither, wrap it in foam padding to keep the vibration down that can cause the fuel to foam and generate air bubbles in the fuel line.

http://www2.towerhobbies.com/cgi-bin...&I=LXL430&P=ML

You need the stuff to wrap your receiver too, to protest it. Don't forget to put a wrap of tape around the crystal if it is exposed to keep it from vibrating loose. The foam will hold it if wrapped properly though.

Wrap the tank with enough layers to fill the space and it will not slide around either.

Edit - last resort if you don't have any foam, use a fluffy old sock. Sounds strange I know but it will work as a last resort. Wrap loosely and secure with a large rubber band.

Boy, am I gonna hear about this one I'll bet. Try to get the foam if you can

If you haven't bought fuel yet make sure that it contains at least 18% oil content. 10% nitro works well, anything with higher won't make much difference on a trainer and is more expensive. A mixture of castrol and synthethetic works best for lots of reasons that I don't want to get into now. Look for what is called "Sport Fuel". The best size props I like for 46 size engines is the 11-5. Gives you lots of pull when you need it and good speed when you want to fun. [8D]

Hi!
The tank should be mounted in lots of soft foam...not the white stuff!.
In a ARF the tank is mostly pushed in and forgotten...

As for glowplugs forget the FOX idle-bar plug. Your engine will work much better if you use an OS 8 or Enya 3 glowplug. These are the two glowplugs that all sport engines will work good on.
Of course there are other plugs too that are good but using one of these will make your engine run good for a long time.
As for props start out with the 10x6. The 11x7 is way to large...do not use it!
The 10x6 Master Airscrew isn't that good though (noisy and bad performance) There are other props that are much better, like APC, Kyosho, Graupner Cam-prop and RAM.
Remember that the 10x6 prop isn't the ideal prop for all airplanes. For a high winged trainer a 11x5, 11x6 or 12x4 APC is the prop size to choose.
For a smaller low winged airplane (around 130cm in span) a 10x6 or a 10x7 APC is the preferred prop.

Regards!
Jan K
Sweden