DeviousDave

Hi guys,

I have a new camera and wanted to experiment with putting videos in Photobucket, so you guys are the guinea pigs:

http://s29.photobucket.com/albums/c2...osser25002.mp4

Temperature in Detroit this afternoon was 32 degrees, this is just a start and fiddle. The engine had already been started because I wanted to be able to do it again one handed, but I made sure to wait until it was cooled off first before starting to give you a more real world idea of what they are like to start. The way it normally works, I don't finger prime enough and have to prime/flip a few times before it burns off the prime after that it takes half a compression stroke worth of finger prime and it fires after two flips and burns off until it has enough heat to stay running-usually two to three primer burns. When indoors it just takes two primer runs to make it run-one to clear out the goop from the previous run and another to get it going.

This restart in the video is typical for indoors, 1/8th of a finger prime and two flips-always two flips for some reason-just like clockwork. The prop is a 6-3 Graupner, the best I have seen is 10k flat. The APC 4.2-4 will turn 13,800 but the engine is harder to tune so I settle for 13,600-700 and a steadier run. The cool thing about the APC's is that they use a spacer to center of the various shaft sizes that electric motors come in and it happens to match the boss on he Schlosser prop drive so you have a HUGE range of props in the 4-8" range to experiment with. I think the 4.5-4.1 will be the ticket for a clean 1/2A model.

fiery

My Feedback: (2)

Nice

Mr Cox

Looks nice, the numbers are very similar to what I get from a PeeWee (0.33cc) on the same 6x3 prop.

DeviousDave

If I am to be honest, I am not terribly impressed with the rpm capability but the tradeoff with friendly starting and handling is worth it. The rod is pretty beefy-I have hydrolocked it a few times and ...may have used an electric starter once.... without hurting it. I have more time on this engine than any of my other diesels by a considerable margin just because it starts so nice and I just like to run it. Eventually it will end up on an airplane because Benno and I would prefer it that way but I am thoroughly enjoying it as it is. When Rob brought it back for me I didn't even want to run it without Gkamysz there for fear of hurting something but in a moment of weakness I started it the night before he came to visit from Chicago. Turns out I needn't have worried at all. I don't have flooding or hydrolock problems anymore now that I stopped port priming it-my neighbors have got to be sick of hearing it run though, but at least it's quieter when not clamped to the balcony rail-the run for the video was a lot louder than normal.

HWM77

Love it electric finger,on a .025 diesel, Dave you should be working for N.A.S.A,id find you a job,maybe you could light the wick!!! Dumb one.

Mr Cox

I don't have any Schlosser engines myself but I just assumed that they are old-school and should be used with a large prop rather than high rpm. A 6x3 at 10krpm is pulling close to 6oz, which not bad for a .25cc engine and should be more than enough for the appropriate plane designs.

If you compare with a sure start for instance that has about three times the cylinder volume it will only spin the same prop around 13krpm...

fiery

My Feedback: (2)

What's your fuel mix Dave?

gkamysz

My Feedback: (19)

Don't let 3000 RPM fool you. That's over 2.2 times the power compared to 10kRPM!

This little engine is great. It handles like it was much larger. Dave just prefers speedy airplanes. I can't count how many conversations we've had about airplanes that go much faster than they should for their size.

DeviousDave

See Guys, the thing is that I don't have enough experience with diesels to know what I can reasonably expect from one-old school or new. To me, it's just an engine (albeit a very cool one) that needs evaluating to see what it is best at. It's very likely that it makes less power on smaller props (Greg calculated a rip-snorting 14 watts on the 4.2-4) than with the 6-3 but that doesn't mean the smaller props aren't the way forward for the type of airplanes I fly. What I'm working towards right now is something with a similar load as the 6-3 Graupner but squarer in pitch and thinner.. I have to experiment because there is so little information available for these engines. The instructions only mention two prop sizes and the RPM listed are quite different considering that there is only an inch in diameter between them so it stood to reason that there was some overhead RPM capability that needed to be looked at. From what I have noted, 13k is probably the practical limit for the engine from a handling standpoint, that's enough to work with and get a nice, fast sport plane. I made sure to get spare rods before playing with prop sizes or using an electric starter-some may not appreciate the effort, I just have a different way of looking at engines than a collector would and enough experience with small engines to know what not to do. Things I don't know about, I just call GKamysz and he points me in the right direction.

Here's a video I found on RCGroups, the prop is a 5.5-2. This video is what has me excited about doing a sport plane for this engine-the flying combination he has is pretty conservative but it's still fast and well powered. I have been flying in this size a lot the last few years with .010 glow and electric, you guys would be amazed at how fast you can go for just a few watts of power. I think it's the best size for former pylon racers like myself who want to really tear around like they are doing something but still are within the scope of a schoolyard flying field. The high water mark will be to compare it to my .010 powered 17" JMGlaskraft Yellow Jacket, which does about 45mph. Even if the Schlosser doesn't have the power the wide range of props I can turn that have high pitch will make up for the power advantage the TD .010 has.

http://www.rcgroups.com/forums/showt...ight=schlosser


Fiery: The fuel is Eric Clutton's Old English. I am fortunate enough to be able to buy direct from him when he comes to the Toledo show-it's about 45 minute's drive for me.

DeviousDave

Life is all about calculated risk-I'd light the touch paper on a N.A.S.A. rocket if it were safe to do.

If you are in control of the amount of fuel going into an engine, an electric starter is fine for small diesels. If you are the type to prime with drops of fuel on an engine this size or leave the needle wide open with the nose pointed down while fumbling with a starter then you'll bend rods. If your settings are already close from the last run and you want to start the engine by hitting the starter button to spin it up, then let go and engage the motor with just the flywheel effect of the start then you'll be fine. Honest Injun.

Now, where'd I put my jar of Nitroglycerine and juggling set...

RocketRob

My Feedback: (1)

try a APC 5.7x3 and tune for 10,2 - 10,600

Warren B

Hi Dave,
I double checked the prop and in fact it is a 5.5x2.5 so just a bit more pitch, but still not much!.

My second 0.25 has been flying a 26" Courtesan on a Master 6x3.
Loops OK from level flight, but I have found the rudder response to be a bit "iffy".
Deciding the problem is actally swirling air in my local flying patch, I'm making another little hot rod for this engine now.

Like the DH02 in my video, this one is also 20" span, but with a flat symmetrical wing and ailerons this time instead of rudder as on the DH02.
It's a bit lighter too.

Will be interesting to compare.
Phots's when I'm done.

DeviousDave

By all means, Warren-show us whatcha got!

Warren B

Well it has flown!
The little Schlosser 0.25 is still running in (5.5x2.5)so I'm being gentle, but it loops, rolls and any other aileron/elevator thing I can think of.
Even does a decent downward bunt despite the fixed pick-up tin tank.
20" span, 5 3/4" cord and a little under 8 ounces.
Covering and markings areAirspan (like Coverlite).

fiery

My Feedback: (2)

That thing is sweet! Video of it flying please!

DeviousDave

Looks great!, what are you using for a fuel proofer in the engine compartment? Is that LiteSpan you are covering with?

ETA: Given the fuel economy I think I am going to try using CA applicator bulbs for a fuel tank. That should give more than enough run time for a small nicad pack's run time.

Warren B

Hi Dave,
I've used Airspan which is like Litespan but without the proofer.
It needs a coat or two of dope to seal and then I used satin polyurethane as proofer.
Airspan + dope ends up a little tighter and more rigid than Litespan, but probably weighs a touch more.
In the engine compartment I smear a layer of 5 min epoxy.

A tinplate tank is really easy (I've got it down to about 1/2 hour to make)my standard design works well now, a rectangular front tapering straightdown in height and width toa 3/16" square point at the back with the pick up in the point.
The bottom face is horizontal.
About 1" wide, 5/8" tall and 1 1/4" back to the point gives plenty of run time.
The vent isin the top at thefront and goes down to the bottom.
To fill, hold tail upward and listen to the tank venting through the engine's intake.

Warren B

New video posted here:
http://www.rcgroups.com/forums/showt...2#post16978203

DeviousDave

I am really impressed with how fast it is for the low RPM and pitch. That looks like a real winner, very well powered even if undercompressed.

peterburford

Warren,
Thanks for posting this.
Peter

Warren B

A pleasure Peter.
By the way, I managed to get a rear induction Mk4 Taipan 2.5from Canada.
I think I remember a comment on a forum somewhere that this was a favourite of yours.
Well it's now a favourite of mine too.
Impeccable manners will always win me over outright power.
Thinking of a Hearns Sportster or maybe Eagle.

Regards
Warren

.... and I should also mention my first engine in 1971 (age 13) was a Taipan2.5 "Ligtning Bolt" glow which started off this grand obsession.
So a vote of thanks to you and yourlate father.

fiery

My Feedback: (2)

Schlosser .25 and friends

ffkiwi

fiery-can you elaborate and give some more detail on the throttle fitted to the MP Jet Classic in the second pic from the left in the second row?

ChrisM
'ffkiwi'

fiery

My Feedback: (2)

Chris

Throttle is available from CS. Very "PAW" like. There are two sizes. They fit the metric 'Mills' type engines.

http://www.csmodelengine.com/?a=product&id=34

Have not run my MP Jet .040 with the throttle yet. I will do so and report once our wet weather abates.

DeviousDave

Does anyone know if David has any more .25's?