MJD

My Feedback: (1)

Man look at the sharp corners on that crank - just run an end mill across it to cut the opening. Did they even break the edges?

That recranked engine sounds pretty happy and healthy. I heard a similar sound yesterday - after running the Picco .40 FAI (and filming it for a change), I set up a smaller test stand with a Novarossi .20 on a 5.5x5 prop. All good, needling up when the C-clamp popped loose, and the stand pivoted to the right neatly trimming the prop tips off on the sharp corner of the bench to 4-1/2" diameter, with a corresponding jump in rpm.. oops! All good, peak hp at 33k anyway and it barely got there before pulling the fuel line. Yes I was safely behind it.. getting a bit wiser in my old age.

Pond Skipper

I have been busy working on another rigger project.
After many flights with Vertigo aka SH-07 engine on the larger Skorch
I had a few more of these engines on tap so converted one for the rigger.
Has a custom made flywheel to my specs and beautiful polished stainless
steel tank to my specs to shoe horn in the nose of the rigger. 364.7g
thus far / all ply with carbon booms.

Pic of the non traditional design drawing to actual.

MJD

My Feedback: (1)

It might not fly, but I gotta say that is some sexy looking hardware.

Any chance you might head to SMALL? I'm going to make a decision pretty soon between that and the pulsejet event in Germany, one weekend apart and can't do both. But I am thinkin' pretty small at the moment.

Pond Skipper

Thank you Mike, is your pulse jet up and running now? I have seen the test launch
and the engine start up vid. Are you wanting to take yours to Germany?

SMALL would be the cheaper option out of the two potential trips. I drove out to SMALL
back in the late 80's when stationed at BAFB not so bad of a drive then.
It's in June again I imagine, the drive now would be soo long it would be the main
memory of the trip lol. Would be a treat to see all the 1/2A flying.

MJD

My Feedback: (1)

It should be back up and going in the spring, the body repair is a bit more of a PITA than I hoped. I don't think I would take it over, the overall cost of the journey would be too much. Just a sight seeing and fact finding mission.

AIrfare to Small is in the $300's for me, not too bad.

Pond Skipper

Matt with EX Models hooked me up with a custom threaded die typically impossible to
find other than at Singer Sewing Machine repair shops.

I took a G-Mark .030 carb from one of 3 engines on hand, the less mint one and re-threaded
the sucker. Worked out perfect and was fast to do from nothing to something special.
The GM .03 is very heavy and cant really scream do to its heavy piston and rod. One thing
it can do is run and idle well. 29.7g with muffler, aluminum carb body and back plate.
Will do a bench test with the stock black 4.5x2 for power reference.
28.5g with stock prop no muffler SPI TD cylinder.


https://www.youtube.com/watch?v=ZKHoiI_dz3g Uploaded on Mar 11, 2017 Small Cox Logo

TD .020 with RC Carb Cox 4.5Dx2P Prop
G-Mark .030 RC carb threaded to aluminum carb body
Cox muffler, aluminum back plate, 1 shim
17,472 best read open exhaust / 16.1k with muffler 8k idle.
Fuel tank was too elevated to be an ideal setup.
SPI cylinder needs to be shimmed. Stock muffler is restrictive
but nice and quite. A machined header for muffler options would
be a big treat.


................

Pond Skipper

https://www.youtube.com/watch?v=_esXapjdHcA Done 457g / 16.12oz less fuel:

SH-.07 Rigger 1.14cc
............

MJD

My Feedback: (1)

Curious - running so light a load, does the engine overrun the pipe and self-govern itself rich, or what happens, are you just real careful on the throttle? On that video where you run the rigger, it's howling at some fearsome rpm before it hits the water, if the engine was any bigger I'd expect to see shrapnel.

p.s. what is the buoyancy when these guys aren't moving - water to the gunwhales?

Pond Skipper

The Picco rigger floated with plenty of breather room see pic.
This new rigger I have not done the float test yet but will it's a must do prior to running
to check for leaks in the hull. The sponsons are balsa core / ply skinned there is no where for water to go.
The .07 is 78g / 2.75oz less weight and more power with the same wide stance 1.14cc vs .85cc
I may enter it in a SAWS event "Straight Away Speed trials". If it gets over 60 mph.

MJD

My Feedback: (1)

I just watched a SAW run of a monster electric setup on YT, I believe it was 8S, 594 amps. High 200's kph each way. How to dump a lot of potential energy FAST..

ha found it.. https://www.youtube.com/watch?v=Fr7D9_V4UZs

285kph. 298.7kph on 2nd pass. He'll pass 300 I'm sure.

Pond Skipper

Ah yep seen it thank you 17kW (590A at 29.0V) 22.78HP Burst .

I have chatted with Jörg and Christian Lucas on the International Waters Forum. I remember when Jörg hit 142 mph
for the first time about 2006 right after getting past the gate he flipped it on the second pass was ok as the deed was
done and even back then with a LMT engine. Who would think such speeds could be reach with riggers that size.
But with elect setups power is a given the true challenge is still in IC. He will hit 200 mph next SAWS event entered.

In retrospect my lil effort with the .07 is with just a mere 185 - 200w to hit 60 will be quite the feat, with a all ply build.

Pond Skipper

Well this skinny version held up with the water test, no leaks and the engine bay is high and dry.
Not near as much hull to counter act the weight so lucky this build came in lighter than the Picco effort.
Shown with no fuel in the tank if with fuel the tail would lift out a bit more. This state of flotation will
be more typical after running out of fuel out on the water. The trick will be to have the will power to
stop the run before I run out of fuel. My guess I will have about 12 mins from bench start to docking.
With the Picco rigger I was mentally done sub 10 mins anyways lol.

....

The nose area is sealed off on the tub combined with the sponsons and the radio compartment
the rigger should stay afloat if flipped plus what ever air is in the fuel tank will add assistance.

Pond Skipper

Mike to answer your question the riggers run on top of the water and stay there through out the run generally.
The rpm is crazy no doubt, for an Italian high performance engine it is able to hold together being so small
the mass to strength is higher big plus. Per your question on the tuned pipe the trick is set it a bit rich it will
sing on the pipe all the same when loaded the heat will build and the richer mix will level off the heat making
for a good balance.

Here is the modified TD .020 bench test, the small hole in the muffler
is killing the top end, was there for goo control, I think the best bet
beyond the backflow benifits for low end throttle is just to run it with
no exhaust restrictions when out at the flying field.

Pond Skipper

FYI did another design / build rigger ready to test with a O.S. Alpha .56 their latest offering rated for more rpm than
previous designs and full oil flow through the engine. Goes out through the exhaust via a small chamber
in the valve box. Eliminates the bleeder nipple on the crank case makes them a better choice for boats no
chance of sucking in water into the crank case or filling the tub up with excess oil. Rigger is 3ft long made for
rougher water weight is 3.2Lbs. / should be good for about 55- 65 mph,

Previously tried a Saito .30 but a bit under propped and it fell off the prop after the turn. Here is a taste
of the effort and the only 4 stroke rigger on Youtube, or even tried do to the lower rpm's not typical to do.

gmeyers

Just curious about a couple of engines -- anybody using or testing an .05 from MECOA or the 1/2 a's from Brodak ??

Pond Skipper

Here you go it's further back in my thread I do quite a bit with a Mecoa sold Fuji .05
I have no viable test on Brodak 1/2A's


Best down wind pass hits 36,747 rpm / 148 mph carbon 4x4.5


Bench testing the HQProp Carbon 4x4.5


1/2A-Engine - Tune Pipes for sale


http://www.ebay.com/itm/1-2A-Engines...item4b22e44ac7



New from the factory . 1/2A Tune Pipe for .049 to .061 (.8 cc to 1.0cc) engines like PROFIs, FORAs GZ, CS and CYCLONs .
Made in the Ukraine

7 left I just bought my 5th one.

Currently use two on boat engines and two on planes needed a spare for bench testing!


Once they are gone he takes over a year to buy more. It has been about 1.6yrs since the last batch.

karyadasarutama

can i know , where buy engine with power 650-700w weight 180gr

Pond Skipper

AmpAbuser
Published on Nov 28, 2015

OS FX .25 with MACS Tuned Pipe APC 8x8 16,149 rpm / 122 mph / 3.1 lbs thrust / .994hp or 742w
Quick rev up during break in mode, header cut to 4.25" Tru Turn 1/4-28 spinner nut.
Weight is over 180g with the tuned pipe engine alone is 248g

Pond Skipper

More work with the TD .020 RC here is the result.


Cox TD .020 with RC Carb / 3.75x4 / 23,032 rpm / 87 mph static
.069hp / 51.47w / 87 mph / 4.6oz thrust / 25% nitro / 20% castor
Should do 29k unloaded / 110 mph