Electric, Nitro, Diesel, Petrol, Balsa, Foam, plastic or Ply - Whats your likes and dislikes ?

[TheFlyingBrit]

Couple of pictures of my Nitro engines, well the bigger ones. I couldn't get to my Cox engines buried alive.
Also added pictures of my cars


The last engine in the row, the Fuji hasn't run in years not even sure if it still will run to be honest.
Didn't bother putting the OS 46 LA as Iv'e already posted a pic of that and its being donated anyway to a friend.

 

[JennyC6]

Can almost guarantee that Fuji will flash right up. Guarantee if it's not been burnt to a crisp with the wrong fuel/lean mix over the years all it needs is fresh fuel and a hot glow plug.

 

[TheFlyingBrit]

Found my Cox engines

 

[Bricks]

My after-run treatment is to run the engine out of fuel, roll it to BDC, and store it in an air conditioned location. The castor oil left in the engine will protect it from rust. Been workin' for me for nearly 20 years now.

As for oil in gas burners...I just use the basic WM stuff at 25:1. I have a literal heap of dead strimmers from running 40:1 50:1 fuel mixes like these engines all call for so I'm just gonna over-oil them. Rather have to deal with fouling a plug every couple years than burning out a jug every couple years. They smoke like they're coal fired but they run cooler and give more power than they do on the 'proper' ratio so I'll roll with it. It's also much easier to mix; just dump the entire little bottle straight into a 1 gallon jerry can and shake well; 40:1 and 50:1 require actually metering out a partial bottle or using a larger can or sommat.

Well maybe using a better grade of 2 stoke oil would help I have got string trimmers and saws over 20 years old and never burned up an engine running my Amsoil Saber. Even though the manufacturer recommends 32-1 I run 50-1 in them not one issue.

One of the guys at the field has been flying his Evolution 10cc ignition gasser at 75-1 ( he is using Stihl Ultra oil ) as a test to see how it holds up. After all summer and many tear downs to look for wear there really has been none. This next summer he may try 100-1 that may be pushing it a bit but they claim you can run it 100-1, we shall see if he does. He runs all his gassers at 50-1 on good oil and never had an oil issue and he is one of those engine nuts constantly tearing down checking his engines modifying to get the most out of them.

 

[skymaster]

would like to try them all . the cons FAA rules

 

[JennyC6]

Well maybe using a better grade of 2 stoke oil would help I have got string trimmers and saws over 20 years old and never burned up an engine running my Amsoil Saber. Even though the manufacturer recommends 32-1 I run 50-1 in them not one issue.

One of the guys at the field has been flying his Evolution 10cc ignition gasser at 75-1 ( he is using Stihl Ultra oil ) as a test to see how it holds up. After all summer and many tear downs to look for wear there really has been none. This next summer he may try 100-1 that may be pushing it a bit but they claim you can run it 100-1, we shall see if he does. He runs all his gassers at 50-1 on good oil and never had an oil issue and he is one of those engine nuts constantly tearing down checking his engines modifying to get the most out of them.

Not really worth the hassle of going out of my way to get those fancy oils when I can just feed a sensibly smokey mix of the stuff I can readily get a hold of to them. Way I see it, if a two stroke don't smoke blue, it's gonna die.

Also, the older strimmers/saws have adjustable carbs. I didn't start having a problem with strimmers burning top ends up until the EPA forced manufacturers to call for wafer thin oil mixtures and non-user-adjustable carbs that inevitably burn them lean. Last one of those cheapies I had would only cut if you held it at 70%; it wouldn't idle, wouldn't transition, was a bugbear to start, ran hotter than a two dollar pistol, and if you pulled full throttle it fell on its face.

Not enough oil, lean fuel mix, cheap power head. It's a recipe for disaster. And I'm sure Walmart is lovin' it, too, because they last juuuuust long enough that the failures aren't covered under warranty. It's probably intentional; they know the engines are going to fail and make you buy a new strimmer every couple years.

the most infuriating thing about it is, if I could adjust the *%)$ing carb, even those junk strimmer engines would run half decent and not burn up in a flash. Fatten the mix up, give 'em 25:1 regardless of what the fuel cap says they want, and they'll stop dying.

 

[TheFlyingBrit]

If I can get my two cox 049s running again they would be ideal for a little twin prop project 2 counter rotating props. I might be tempted to build a small Mosquito just for the hell of it out of foam. I could use all my scrap sections of foamboard and remove the paper, two birds with one stone a bit of upcycling
It will have to be after my sea otter build, but may squeeze it in before my Warthog A10 project.

 

[JennyC6]

If I can get my two cox 049s running again they would be ideal for a little twin prop project 2 counter rotating props. I might be tempted to build a small Mosquito just for the hell of it out of foam. I could use all my scrap sections of foamboard and remove the paper, two birds with one stone a bit of upcycling
It will have to be after my sea otter build, but may squeeze it in before my Warthog A10 project.

You'll get about 40 watts out of them. ~200 grams thrust. Keep your AUW under 500-600g and it should fly just fine.

I'm prolly gonna do a Cox TD049RC powered FT Mini Cruiser build soon.

 

[TheFlyingBrit]

Sounds great keep me updated on the cruiser, interesed what sort of thrust angles you will go for ?

 

[JennyC6]

Sounds great keep me updated on the cruiser, interested what sort of thrust angles you will go for ?

Prolly whatever FT call for in the build. Twins are pretty lax about thrust angles. And the real nice thing about that build is I shouldn't have to worry about CG because the engines are so much closer to CG than they would be on any of the other minis...save perhaps the mini guinea.

 

[TheFlyingBrit]

Thought the contra rotating props would probably cancel out each other, but wasnt sure about down trust ?

 

[JennyC6]

Thought the contra rotating props would probably cancel out each other, but wasnt sure about down trust ?

with counter-rotating props you should be fine with 0-0. I'll have to check but I think my TwinStar is also 0-0 and it has two normal rotation engines on it.

Twins really are pretty IDGAF about thrust angle.

 

[speedbirdted]

I wouldn't want to try a twin with Cox power... mostly because there's no throttle cut, so you can easily end up in a situation with one engine going at full beans and the other dead which is a breeding ground for irrecoverable spins. An exception would be if you can feed both of them from a single external tank instead of their individual integral tanks, so then they'll both die at roughly the same time. Cox Int. sells a backplate with a fuel nipple instead of the tank for the reedy engines; Cox has made a lot of reedy engines but I don't think the dimensions in this area have really changed throughout the production run so they'll likely drop right in without a hitch.

You'll get about 40 watts out of them. ~200 grams thrust. Keep your AUW under 500-600g and it should fly just fine.

Most of the reedies will give you about 50. Black Widows maybe a little more, I've never had one so I'm not entirely sure. TDs can do close to 100 if you prop them to spin into the 20k+ range (which will piss off your neighbors. Don't ask me why I know)

 

[JennyC6]

Thought the contra rotating props would probably cancel out each other, but wasnt sure about down trust ?

Did some more looking. A good safe bet to give you insurance in an engine out situation would be 1-2 degrees 'out' thrust and 1-2 down on a low-wing twin.

I wouldn't want to try a twin with Cox power... mostly because there's no throttle cut, so you can easily end up in a situation with one engine going at full beans and the other dead which is a breeding ground for irrecoverable spins.

My TD049 build will get around that because I'm gonna get a couple of those airbleed carbs from EX Model Engines and slap them right on. They'll be fully RC, including the ability to throttle cut them, to power back in an engine out situation, all that good stuff.

You could also use the exhaust throttles but I don't know what those do to power at full blast compared to no throttle at all.

An exception would be if you can feed both of them from a single external tank instead of their individual integral tanks, so then they'll both die at roughly the same time. Cox Int. sells a backplate with a fuel nipple instead of the tank for the reedy engines; Cox has made a lot of reedy engines but I don't think the dimensions in this area have really changed throughout the production run so they'll likely drop right in without a hitch.

Yeah, I had the twin 049 setup on my Spear running off a single tank. Need to revisit that thign with a 20 2c though.

Most of the reedies will give you about 50. Black Widows maybe a little more, I've never had one so I'm not entirely sure. TDs can do close to 100 if you prop them to spin into the 20k+ range (which will piss off your neighbors. Don't ask me why I know)

My RC Rangers never gave me more than 45, but I also propped 'em kinda slow. 6-4 TF Wood. Might also have been the mild cylinders used with the safety slits.

The higher power of the TD is why I'm planning on using two of them in a Mini Cruiser brapification build; slap some 5-3 APCs on 'em and I'll be cookin' with nitro as it were. 100w each nacelle should be roughly equivalent to an A-pack if memory serves. Will run 1oz roundies in each nacelle to feed them since they're so far apart and the TDs don't have a tanked backplate option.

 

[TheFlyingBrit]

Come up with an idea based on the seperate fuel tank feeding both motors, what if a control valve was fitted between the fuel tank and engines as a throttle, with a 5g servo operating a linkage. Even if it was just as a throttle cut off it would have a benefit.

 

[JennyC6]

I have such a valve in my 'to be 3d printed' stash once my printer's dialed in and consistent. Just pinches off the fuel line.

 

[TheFlyingBrit]

Sounds excellent I was thinking along the lines of taking a throttle/carb assembly of a scrap engine and adapting it so you get a choke effect. but having a twin outlet feeding both engines.

 

[JennyC6]

Sounds excellent I was thinking along the lines of taking a throttle/carb assembly of a scrap engine and adapting it so you get a choke effect. but having a twin outlet feeding both engines.

That would be so heavy and it'd probably just cause a lot of problems getting a decent fuel mix.

 

[TheFlyingBrit]

just the carb wouldnt be heavy but getting the mix right would be a pain.

 

[Bricks]

I do not think the could pull fuel from a tank set up in the middle of the plane feeding both engines unless a pump or maybe muffler pressure was used. Or find 2 of these Norvel engines I have one a T28 trojan hard to get used to the idle around 4,500-5000 rpm but the plane does not move.

NV Big Mig 061 R/C (nvengines.com)