Hobbsy

My Feedback: (102)

Mike, when I was learning to fly RC in about 1991 I flew at Fort Belvoir. We had trees at our back and the wind came across the flat then rolled upwards and bock down. It would quite literally push a plane down on the run way. That SpaceWalker and the .56 were meant for each other.

mike109

G'day Dave. Yes, we call it "the washing machine effect". It can be very dramatic. I was landing my Four Star 60 (Saito 100) on one occasion and I was almost over the end of the strip and at about 20 feet when the plane rolled through 90 degrees. That sort of thing really gets the adrenalin pumping.

Once you get above the level of the top of the trees things are much better and really close to the ground it also calms down but the transition zone in the middle is not fun.

The Space Walker has had several engines in it. I tried a Saito 72 at first but it was too heavy so I put a 62 in and that was OK but I have decided to try the 56 as it is not all that much less powerful than the 62 and it is a little lighter. I will be interested to see how it goes.

Cheers

Mike in Oz

SrTelemaster150

Try landing over standing corn that comes right up against the runway.

I once had a nasty little stall just as I came over the edge. The breeze was hitting the corn & causing an updraft. As soon as I came over the edge of the mown field, my Dynaflite PT-19 dropped its nose & dove about 6' but it wasn't so severe that I couldn't save it few feet off the ground.

blw

My Feedback: (3)

It does the same thing to full scale too. It almost cost me getting through flightschool on a big checkride.

Hobbsy

My Feedback: (102)

Barry, I gather you're talking about the new B back plate, Thanks, Dave

blw

My Feedback: (3)

The metal backplate for the 72? Yes, that's the one along with 91 carb screws. I think I'm going to end up with a couple on packages of the improved plastic ones that I won't be needing any more.

SrTelemaster150

Kinda like the drawer full of perfectly functional glow plugs that I no longer have a need for.

Anyone want to trade some burned out glow plugs for good ones. I have a couple of dual plug Saito twins that I have to "plug" the extra hole W/a burned out (or drilled out) glow plug.

spd101

I have 4 Saitos right now: a 91s in a H9 Corsair, a 91s in a H9 P-40, a 91s in a GP Revolver, and a 100 i my new TF Cessna 182. I won't ever own another brand of 4 Stroke

Ernie Misner

I think William Robison once said that being inverted = better cam and valve train oiling properties. Makes sense (gravity) and sure didn't hurt this engine any!

hsukaria

Now you tell me!! I threw away a few plugs lately from breaking in engines, failed ones, etc...

Meanwhile, I have been enjoying my FA82 tremendously on the U-Can-Do 46 with a 14x6 APC prop, 20/20/60 all synthetic fuel. I think the FA82 is the ultimate engine for the U-Can-Do 46. I think I will be saving my pennies to buy another for a warbird build for my son. He just recently turned 17 and he suddenly got some interest in RC planes. He hasn't gotten very distracted by girls yet.

Hobbsy

My Feedback: (102)

I discovered years ago, about 23 in fact, that break in plugs last every bit as long as new ones. I discovered that because I never
considered that a plug would be compromised during the break in process. My 1991 Enya .46 MKII still has its original Enya 3 in it.

hsukaria

Well, maybe I am doing something wrong then, or using wimpy plugs.

I know one of my engines is bad on plugs and blows them (from heating too much). I am about to send that engine to the manufacturer to have a look at it. It is not a Saito, but still a good reputable company that stands behind their work, unlike some of the other engines I recently bought that are throw-aways. I bought that engine used and "fixed" it, but apparently not enough.

Another reason might be is that I have been flooding my engines with ATF for storage, but not flushing them before starting them. They initially splatter ATF all over as I spin them to start them at the beginning of the season. Maybe something in the ATF or the excessive pressure from all that fluid?

Finally, it could be the plugs themselves. Maybe wrong heat range or less robust design. I have recently switched from 15% nitro to 5% nitro on all my 2-stroke engines and have had to re-tune . I also switched from 15% to 20% nitro for my 4-strokes and had to re-tune them also. So, it may be that I had not done a thorough job at re-tuning?

Anyway, it is not a crisis since it is not on-going except for that one engine that is fairly high compression and I will be sending it in for a check-up soon.

As far as failing a plug during break-in, I think it happened on the latest engine I just broke-in a couple of weeks ago. But I was using an old plug that came from that hot high-compression engine. So, it makes sense that I check out that engine for any issues.

blw

My Feedback: (3)

I guess I'm stuck in the old school way of using the same set of used break in plugs to break in a new engine, and then putting in a new plug when it's done. That always works too.

hsukaria

I plan to keep that habit also. But I also have been frying too many glowplugs the past year or so. But this problem is all from my 2-stroke engines. I use the same type of plug on my 4-strokes. But on the 2-strokes, I have been using either a cold plug or a hot 2/4 stroke plug that I use on the 4-strokes. I might try a medium plug since it might be that I am trying to tune some engines on too-cold or too-hot of a plug?

Regardless, I still have to address the issue of the one engine that keeps frying plugs.[&o]

N1EDM

My Feedback: (2)

I had that happen to me a couple of times. I wonder if, because it's a new engine, there are fine particles of metal still inside that migrate to the glow plug and shorten its life? Then, the next plug (with the engine now cleaned out) lasts longer because all the contamination is gone.

Just a thought,

Bob

blw

My Feedback: (3)

Bob,

There's always some amount of metal swishing around. I learned this from metal chip detector plugs in turbines, and seeing what the lab had to say on oil samples we sent in. I just figure that stuff could stick to the glow plug element. Probably doesn't matter often when you have engines like Dave's 1991 Enya though.

What would a small rubber band do to a new engine? I found one lying inside of the backplate.

N1EDM

My Feedback: (2)

I'll stick my nose back in here again... I'll bet that rubber band would also destroy a glow plug if it happened to get a blob of molten rubber on the element...

Just a SWAG on my part.

Bob

Rudolph Hart

I have 2 82's and they are my most used engines,lots of power/performance for little fuel try one in a 46 size decathlon.No plug issues.

I see some comments on turbulence above,we also have that issue when it blows from the ne which it does quite often here.Has anyone applied for the pilots job advertised over in giant scale-general?? you should have a read it's lots of fun.

SrTelemaster150

Not likely to happen in a 4-stroke. No way to get into the combustion chamber from the crankcase. If it was in the chamber from assembly, I doubt that the engine would even start.

jkr_1100

My Feedback: (15)

Old fart nice picture on your account. I suppose you are finally into the "cold" part of winter there. we are in the hot part of summer here on the other side of the world

Rudolph Hart

Lucky you;0 man we're freezin here.You go from one extreme to the other.In summer you can fly in temps up to 45c (115f) and now it's minus 3 celsius(don't know what that is in degrees f)

N1EDM

My Feedback: (2)

I hate to agree with you, Sr., but that's a good point... unless you were getting blow-by past the ring which is a pretty low probability

Bob

jkr_1100

My Feedback: (15)

Its COLD , thats what it is in F. I hope you get a chance to lift off once in a while despite the cold.

SrTelemaster150

+26.6°F

I've personally seen -37°F (-38°C) in my driveway & the record for Massena, NY (on the Canadian border eh?) was -50 F (-during the building of the St Lawrens Seaway back in the '50s.

You don't know what cold is pardner!

SrTelemaster150

Really?