Getting started in the hobby! First planes, first impressions

[gandalfnz]

I have an Asp FS.80 on hand that I picked up based on that earlier discussion and it just seems a bit too big / heavy.

The .62V is pretty modern, OS rates it as having the same power as the Surpass .70, 1.1hp at 11k RPM, so I'm optimistic. I'm going to give it a 4-blade 12x6 wooden prop, black with yellow tips. $25 from Ali.

The Ali glow driver arrived, I was able to set it up to work exactly how I'd wanted - on, off, and idle support that turns off above 20% (or any set point) throttle. It only turns the ignition on at "max" signal, and turns off entirely below the default "center", so with a little trim and mixing it wasn't too hard to get it to work as intended, at least in bench tests. It even functions as a continuity check for the glow plug coil with an indicator LED.

I'm tempted to put it on the Avistar to test it, but I'm pretty happy with how that .52 FS is running, so I'll probably leave it for now. Weather has gotten prohibitive for flying recently, I'll be lucky to get any more flying days in before next spring.

I have a VQ D3A1 Aichi plane, which hosts a .91 Magnum, granted I haven't flown it yet because I need to figure out why fuel once past half empty stops coming out, even when I used the fuel pump, it just wont drain the fuel past certain level. Weird. Guy I purchased it from did say it flies amazing.
I have also picked another pair of Magnum 91's for my other projects of similar size.
Have you figured out whether the CG is good with that 62 on? Just clamp it on somehow and see where it balances, make sure you got all the other gear installed though such as servos, fuel tank, battery ....etc. Ideally you want it to be a tad nose heavy without needing to add any lead weight on. I am not a fan of adding additional weights and like to balance it all out without it.
The engine might seem too big, but I would go for that .80, you will have to make cut outs on the cowling for it to fit over the engine, so its likely that at least the rocker cover will be sticking out the bottom, but this is also good for engine cooling.
In terms of physical size, I think there might not be any difference between a .80 and 91, which is why going all out, might not be a bad idea.
It would be very cool to see that warbird do a vertical climb!

Would you mind explaining in greater detail on how you connected and made the onboard the glow driver work?

Thanks

 

[tudordewolf]

Would you mind explaining in greater detail on how you connected and made the onboard the glow driver work?

The glow driver has a servo plug that goes to the receiver, and an optional button which triggers the ignition for a few seconds. I didn't use the button at all. It also has a negative lead with a terminal meant to go under one of the engine mount screws, and a positive lead with a cute little clip-on head that looks like a spark plug boot.

I plugged it in to channel 8, and assigned that to a 3 position switch. Right off the bat, the 3 default positions corresponded to the 3 settings of the driver - 1.4V, 0.8V, and 0V.

Then I mixed throttle in, "+20% low", which means it mixes in the throttle's value slightly when it's in the bottom half of its range. This has the effect of nudging it "down" one setting, and by adjusting sub-trim on the remote, I'm able to choose where on the throttle travel that transition happens. I also set the mixing to be toggled by a switch - the same switch I set to control ch. 8, and I set it so that the mixing is only active when it's in the center position. That way, the throttle doesn't nudge the ignition position down into idle support, but it will nudge it from idle to off.

It also says 7.4V - 12.6V input, but I tested it on 6V without any problems.

 

[gandalfnz]

The glow driver has a servo plug that goes to the receiver, and an optional button which triggers the ignition for a few seconds. I didn't use the button at all. It also has a negative lead with a terminal meant to go under one of the engine mount screws, and a positive lead with a cute little clip-on head that looks like a spark plug boot.

I plugged it in to channel 8, and assigned that to a 3 position switch. Right off the bat, the 3 default positions corresponded to the 3 settings of the driver - 1.4V, 0.8V, and 0V.

Then I mixed throttle in, "+20% low", which means it mixes in the throttle's value slightly when it's in the bottom half of its range. This has the effect of nudging it "down" one setting, and by adjusting sub-trim on the remote, I'm able to choose where on the throttle travel that transition happens. I also set the mixing to be toggled by a switch - the same switch I set to control ch. 8, and I set it so that the mixing is only active when it's in the center position. That way, the throttle doesn't nudge the ignition position down into idle support, but it will nudge it from idle to off.

It also says 7.4V - 12.6V input, but I tested it on 6V without any problems.

I am so confused in regards to the last paragraph. Will go ahead and order a few units then start fiddling with it and ask you questions.

From which seller did you get your on board glow drivers?

 

[tudordewolf]

I am so confused in regards to the last paragraph. Will go ahead and order a few units then start fiddling with it and ask you questions.

From which seller did you get your on board glow drivers?

I got this one because it was cheapest for me. That seller's got some interesting engines, too, some gasoline 2- and 4-strokes by NGH.

I'll try to simplify, with some screenshots. This is going to be Radiolink specific, but the functionality should be reproducible on most hobby radios.

I set channel 8 to a 3-position switch, switch G, and plugged the glow driver into Ch.8.

Its behavior is such that at from "100 to 1", it is "off", providing no current. From 0 to -99, it's on idle support, providing 0.8V. Then, only at "-100" or beyond, does it provide the full 1.4V for starting. Since the 3-position switch defaults to -100, 0, and 100, that means the it selects between the 3 modes.

I used sub-trim to control the cutoff point for idle support, so that the more trim I apply, the more the throttle has to "add" in order to turn it off.

Then, I mixed channel 3 (throttle) to channel 8, so that when I throttle up, channel 8 goes from 10 to some negative value, turning the idle support off as it crosses the zero mark. By adjusting the amount of mix and/or the amount of sub-trim on channel 8, I can adjust where on the throttle the transition happens.

Radiolink allows you to set toggles on the mixing, (called "link", in the screenshot) so that you can assign a switch to enable or inhibit the channel mixing. It lets me use the same switch for this toggle as the one that's controlling channel 8, and I set it so that the mixing option is only enabled when Switch G is in the center position:

 

[tudordewolf]

I am so confused in regards to the last paragraph. Will go ahead and order a few units then start fiddling with it and ask you questions.

From which seller did you get your on board glow drivers?

Installed it in the Avistar and did some testing, got some interesting results. Main takeaway is that it's a little too powerful voltage-wise, I'm able to start the engine just with the "idle support"

Tucked it under the fuel tank, re-did the firewall-sealing foam to pass the wires through.

And the ground terminal, I just added another m3 washer over the bit of exposed "post" instead of undoing the engine mounts.

I tested it by powering a cheap HSP glow plug directly from the leads, and it blew out within seconds. I got another one, and it glowed like it does on an ignitor at only the "half" setting, 0.8V. I got a DC power supply and set it to 1.4V, 5A limit, and got the same result with a blown out plug after briefly glowing almost as brightly as a flashlight.

I'm going to try a 0.1 ohm resistor to drop the voltage just a bit, so that both power levels are useful. I'm not sure idle support is "necessary" on a tuned engine, it was nice starting it without messing with a glow ignitor, just a switch on the transmitter. It might be useful for finding an extra-low idle, I didn't experiment with that yet.

Also did the valves, what a difference that made.

Thanks for the recommendation, the engine was running well enough so I would've probably left it alone until it became a problem. They were both out of tolerance, over 0.14mm, could fit both feeler gauges together under both rockers. Got them tightened down just so that the 0.04 gauge could slide around. The engine absolutely purred after that, I'll get a video up. Also, its visible in a few of the pics, I've been running the Brodak air filter on it without issue.

edit, videos:

 

[gandalfnz]

Thanks for explaining all that.

The mixing, I am completely unfamiliar with, so finding it hard to understand that part.
Once I get mine, I will be back with more questions regarding the on board glow.

You said that it glows fine on 0.8v, how did you then manage to blow the second plug?

Nice flying and landing. can't wait to try my SIG 4*40 and ASP 61.
That 2 stroke screams so much, it give the illusion that it flies 3X as fast as a 4 Stroke!

 

[tudordewolf]

You said that it glows fine on 0.8v, how did you then manage to blow the second plug?

The first time I did it with the onboard glow driver, the second time I did it with a bench power supply so that I could monitor the current and verify that 1.4V had really blown out a plug. At 0.8v it was drawing 2.4 amps, at 1.4V it rose to over 4 amps then blew. From that I figure the glow plug has about .33 ohms of resistance, so if I put a .10-.15 ohm resistor in series, it'll drop the voltage reaching the glow plug just a little, and also reduce the current in the process, such that I'll have more like 0.6V / 1.1V instead of 0.8 / 1.4. For plug longevity, I want the lowest voltage that'll still start the engine, so I'll probably try a few and go with the highest value that still works.

That 2-stroked Sonic is substantially faster, it's only 1.3M and ~2kg to the Avistar's 1.6M span and 3kg. It's marked as a ".25-32" plane and I stuffed a .46 in; the engine mount barely left room for the throttle rod-

And from underneath, you can see that there's no space left on the other side, and also shows how I milled "flats" into the bottom of the engine mount so I could use m3 hardware instead of screws biting into the plastic. (though I did only drill them to 2.5mm and drive the bolts through anyway, I'm all about overkill)

That said, by virtue of being a bushed engine, the .46 LA doesn't weigh any more than ball-bearing based engines like the OS.25-FX or SH.32, ~330-350g with muffler, but it'll still swing a 10x7 prop at 10k RPM, even with that tailpipe I put on it.

 

[gandalfnz]

The first time I did it with the onboard glow driver, the second time I did it with a bench power supply so that I could monitor the current and verify that 1.4V had really blown out a plug. At 0.8v it was drawing 2.4 amps, at 1.4V it rose to over 4 amps then blew. From that I figure the glow plug has about .33 ohms of resistance, so if I put a .10-.15 ohm resistor in series, it'll drop the voltage reaching the glow plug just a little, and also reduce the current in the process, such that I'll have more like 0.6V / 1.1V instead of 0.8 / 1.4. For plug longevity, I want the lowest voltage that'll still start the engine, so I'll probably try a few and go with the highest value that still works.

That 2-stroked Sonic is substantially faster, it's only 1.3M and ~2kg to the Avistar's 1.6M span and 3kg. It's marked as a ".25-32" plane and I stuffed a .46 in; the engine mount barely left room for the throttle rod-
View attachment 208959
And from underneath, you can see that there's no space left on the other side, and also shows how I milled "flats" into the bottom of the engine mount so I could use m3 hardware instead of screws biting into the plastic. (though I did only drill them to 2.5mm and drive the bolts through anyway, I'm all about overkill)

View attachment 208960

That said, by virtue of being a bushed engine, the .46 LA doesn't weigh any more than ball-bearing based engines like the OS.25-FX or SH.32, ~330-350g with muffler, but it'll still swing a 10x7 prop at 10k RPM, even with that tailpipe I put on it.

Hi

I have decided to do a 45 degree install on my Piper 20 FS20 build.
Just to avoid having to add additional weight and an extra battery for on board glow, plus potential issues with running inverted.

I have added another small one to my FS collection...

 

[CertifiedMike]

I love reading this thread! Reading and hopefully absorbing some experience here is great!

 

[Hobbydude2]

I got this one because it was cheapest for me. That seller's got some interesting engines, too, some gasoline 2- and 4-strokes by NGH.

I'll try to simplify, with some screenshots. This is going to be Radiolink specific, but the functionality should be reproducible on most hobby radios.

I set channel 8 to a 3-position switch, switch G, and plugged the glow driver into Ch.8.

Its behavior is such that at from "100 to 1", it is "off", providing no current. From 0 to -99, it's on idle support, providing 0.8V. Then, only at "-100" or beyond, does it provide the full 1.4V for starting. Since the 3-position switch defaults to -100, 0, and 100, that means the it selects between the 3 modes.

View attachment 208611

I used sub-trim to control the cutoff point for idle support, so that the more trim I apply, the more the throttle has to "add" in order to turn it off.

View attachment 208610
Then, I mixed channel 3 (throttle) to channel 8, so that when I throttle up, channel 8 goes from 10 to some negative value, turning the idle support off as it crosses the zero mark. By adjusting the amount of mix and/or the amount of sub-trim on channel 8, I can adjust where on the throttle the transition happens.

Radiolink allows you to set toggles on the mixing, (called "link", in the screenshot) so that you can assign a switch to enable or inhibit the channel mixing. It lets me use the same switch for this toggle as the one that's controlling channel 8, and I set it so that the mixing option is only enabled when Switch G is in the center position:
View attachment 208609

My dx6 has settings for all kinds of parameters on each plane I have on there. I know for sure that there are some adjustments that could really mess things up. I love the bind and go birds.

 

[tudordewolf]

Gave the Avistar a 3-blade 11x6, because I just like how it looks:

will try to test fly soon, with extra glow driver resistor.

 

[Hobbydude2]

Gave the Avistar a 3-blade 11x6, because I just like how it looks:
View attachment 209891
will try to test fly soon, with extra glow driver resistor.

Woooweee, Sexy birdy. I too like the 3 bladed birds, 2 blades wind up quicker but, the 3 blades look cool and perform just as well.

 

[tudordewolf]

Hi

I have decided to do a 45 degree install on my Piper 20 FS20 build.
Just to avoid having to add additional weight and an extra battery for on board glow, plus potential issues with running inverted.

I have added another small one to my FS collection...

View attachment 209546

I recently got a prize four-stroke myself, a Thunder Tiger .54fs - Maybe not as known for their four strokes as OS or Saito, but I like having as many different makes as possible. Not sure what I'll put it in yet.

Took the Avistar out, the Asp .52 took a 3-blade 11x6 very well, tach'd it at 9400rpm, and with the idle support dialed in it holds an idle so low you can see the individual puffs of exhaust hanging in the air. I put 0.2ohms of extra resistance on the ground line, and that brought it down to about 1amp of current flow at the "support" setting, and a little over 2 amps at ignition, and it had no trouble starting even in 37°F weather.

... it did twist the prop until it hit the spinner, guess I didn't tighten it enough. I'm considering an 11x7x3 based on some other forum posts about the .52FS, but the 11x6x3 performed admirably.

 

[tudordewolf]

Flew it and the Sonic some more today, finally clocked the Sonic, it lives up to its name:

And that's with the tailpipe going all the way back past the elevator.

And corrected the spinner:

 

[gandalfnz]

Plane looks very nice.
Love the 9Ah batt on the heat gun. I stopped pre-heating my engines, even though I too acquired a batt powered heat gun.

Family time taking most of my free time right now, so planes are are on the back burner for now.
Was hoping to go flying this weekend but something has come up.

In saying this, I am in the process of purchasing my first Gas plane, will leave it as a surprise till I actually have it in hand.
Also, selling off some of my collection to make room for some favorites.

On the engine side, just recently I acquired this little .07 Thunder Tiger engine, its incredibly small, almost the same size as a Cox 049.
Needs a wash, excellent compression. Don't know if I will ever get to use it, but it cost me peanuts.

 

[tudordewolf]

Plane looks very nice.
Love the 9Ah batt on the heat gun. I stopped pre-heating my engines, even though I too acquired a batt powered heat gun.

Family time taking most of my free time right now, so planes are are on the back burner for now.
Was hoping to go flying this weekend but something has come up.

In saying this, I am in the process of purchasing my first Gas plane, will leave it as a surprise till I actually have it in hand.
Also, selling off some of my collection to make room for some favorites.

On the engine side, just recently I acquired this little .07 Thunder Tiger engine, its incredibly small, almost the same size as a Cox 049.
Needs a wash, excellent compression. Don't know if I will ever get to use it, but it cost me peanuts.

View attachment 211445

View attachment 211446

View attachment 211447

What a coincidence, I have a bid on one of those new-in-box counting down right now. They're pretty interesting. I hear if you can get a turbo head for it, it benefits, being a small-displacement, high-RPM engine, according to this thread. It's the smallest one with a "true" muffler if you go by the arbitrary definition I just made up requiring the exhaust use mounting bolts, a gasket, and a baffled pipe. There's even a muffler extension for it, TT part #9707, which is notable for just how esoteric a need that envisions in order to have been produced. If I win the auction, I will of course buy the extension for the muffler which is also listed and use it out of principal.

That's an Ali battery, Makita never made that style deeper than 2 parallel, Ali has them up to 5 deep holding 25 cells, which I can see the merit of as a jumbo power-bank, which I use mine as to recharge at the field, directly into the battery charger. I believe I posted a pic of that setup.

The added stature places the nozzle right at engine-height so I can just leave the heat gun on low gently warming the whole engine, particularly helpful since it was 37F last time I was out.

I scooped up a super-neat old ARF, a .25-32 Bipe, going to see if the TT F-54s fits, or maybe swap in the Asp .52 since it's nicely broken in and slightly narrower. Apparently it's from 2003, only ~130 were made and then initially sat semi-forgotten before being distributed through a limited number of "Hobby People" stores, according to this forum post from 21 (!!) years ago. It hasn't even arrived yet, I'll make a build thread of it.

The Mustang nears completion, figuring out how to mount the spinner has been a comedy of imperial and metric thread mismatching. The OS 62V had a 1/4-28 crank thread, same as the Asp and most engines that size, but Saito uses an M7 Crank thread. So I bought a Hangar 9 spinner nut adapter, but now that uses a 10-32 nose-bolt instead of M4. So my Avistar has a spinner nut marrying an imperial-thread crank to a metric nose bolt, and the mustang will have the exact opposite, a metric crank thread married to an imperial nose bolt, which I was able to make work by drilling out the Aliexpress 4-blade spinner and countersinking the nose "well" for the larger bolt head.

 

[gandalfnz]

Hey Mate

Sorry, I haven't had the time to lurk the forums lately, life with 3 kids is hectic at the moment. So much so, that I canceled my aero club membership a month ago, due to no flying for a long time.
I am hoping to get back into it again, hopefully sometimes soon.

How's the Mustang build going, must be finished by now?
I have been watching your videos on YouTube though (subscribed), and I can see you are having a lot of fun with small wee Cox engines!

Big reason for this post today, I finally obtained something that I have been looking for, for a very, very long time. Could never source one, or afford to pay the extremely high asking eBay prices.

Please check the car section of the forum for the big reveal!

 

[tudordewolf]

Hey Mate

Sorry, I haven't had the time to lurk the forums lately, life with 3 kids is hectic at the moment. So much so, that I canceled my aero club membership a month ago, due to no flying for a long time.
I am hoping to get back into it again, hopefully sometimes soon.

How's the Mustang build going, must be finished by now?
I have been watching your videos on YouTube though (subscribed), and I can see you are having a lot of fun with small wee Cox engines!

Big reason for this post today, I finally obtained something that I have been looking for, for a very, very long time. Could never source one, or afford to pay the extremely high asking eBay prices.

Please check the car section of the forum for the big reveal!

Welcome back! I saw that post and sent you a note before seeing this one, awesome find on that bike, that's definitely one of my "unicorns," too.

I did indeed fly that Mustang, though only once so far - the relief of landing it intact after a dicey maiden was significant.

One of your last posts was about acquiring a Thunder Tiger GP-7, you inspired me to do a build with one which I'm very happy with the results of. It has me feeling the itch to make a bunch of 1/2A planes with "mini" engines. The mini stick kit, one of the first I built, before even flying my first nitro, sat "naked" for over a year but is nearing completion:

 

[gandalfnz]

Welcome back! I saw that post and sent you a note before seeing this one, awesome find on that bike, that's definitely one of my "unicorns," too.

I did indeed fly that Mustang, though only once so far - the relief of landing it intact after a dicey maiden was significant.

One of your last posts was about acquiring a Thunder Tiger GP-7, you inspired me to do a build with one which I'm very happy with the results of. It has me feeling the itch to make a bunch of 1/2A planes with "mini" engines. The mini stick kit, one of the first I built, before even flying my first nitro, sat "naked" for over a year but is nearing completion:
View attachment 234970

Love the small planes. I struggled to understand what 1/2A plane even means, and why they wouldn't just quote them by the wingspan.
Planes with 1.2m wingspan really do it for me, easy to transport and fly well. You don't see many of those at the club anymore, mostly much bigger variants.

I get a weird felling in my gut when I take off on a maiden flight, but always do it with a mate at the club, either him or me will take off while the other one helps with the trimming.

I never ran the GP 7 engine, after finding out online/forums that ppl called it gutless for its size, it was stashed away in a box.

 

[tudordewolf]

Love the small planes. I struggled to understand what 1/2A plane even means, and why they wouldn't just quote them by the wingspan.
Planes with 1.2m wingspan really do it for me, easy to transport and fly well. You don't see many of those at the club anymore, mostly much bigger variants.

I get a weird felling in my gut when I take off on a maiden flight, but always do it with a mate at the club, either him or me will take off while the other one helps with the trimming.

I never ran the GP 7 engine, after finding out online/forums that ppl called it gutless for its size, it was stashed away in a box.

I agree that it's an esoteric and arbitrary category. I'd cautiously call it a "sub-1 meter" class in your terms, with exceptions in both directions. I guess it's the nitro version of "parkflyers," also an ambiguous definition that'll vary from person to person depending on the size of their local park.

I read all the GP-7 threads I could find and saw the "gutless" comments myself, but I love it. It's a completely different engine than the other "tiny" ones.

It's the only one that isn't drenched in oil after a run, and it's the only one I was comfortable breaking in without earplugs - it can idle down to a purr you have to hear to believe. It sounds like an idling .46 with the volume turned down, you could have a conversation over it without raising your voice.

It starts easily, 2oz is enough fuel for a 10-minute flight & reserve, and the plane lands with just the underside of the wing oily nearest the exhaust. I don't know what else I could ask of it.

I think part of the issue is a lack of plane/kit options that'll be the right size for it. It'll be underpowered in a plane that was expecting a .10-.15, and it's twice as heavy as a .049, so it'll be too heavy for a plane designed for a Cox engine.

If you wanted all-out power for a speed record plane with the ability to fly straight up like a rocket, it might not be the best choice. I got an AP .061, and THAT is the tiny engine you want if noise and oil are no issue. It is loud and powerful for only 55g. I'm planning on putting it in a sub-250g speed build.

I've also extended my mini air filter design to work for the smaller engines: