RE: Silver Swallow Pulldown
 

Cool - glad to see they arrived OK

Between the two 1.49's , you have enough good parts to carry on and make another, and try a few things out.

RE: Silver Swallow Pulldown
 

Yes after my last try looks like anything will work as long as the piston and cylinder fit is good , balanced or totally unbalanced seems to run OK
I would like to try a Mini Early Bird or a small Dominator combat wing with a severly modified 1.49 on the front that would be fun

My Silver Swallow runs fastest when its burping and set real lean, sort of a ragged missfire

RE: Silver Swallow Pulldown
 

I will find the NV I forgot to enclose .... you will need it. I also think there is a spare Compression adjuster as well.

Will check tonight if the shed is not too hot. We are sweltering up here.

RE: Silver Swallow Pulldown
 

In the 1.49 that Fiery gave me


Im Combat tuning the crank , bigger hole and OS15 glow timing ???

and I made the counterweight look like a Fora Counterweight ,


new lighter prop driver and top secret enlargement of the hole



between the inlet and the counterweight , sorry no pictures as my camera is still lost

Next is piston lightening as its 2mm thick , thats thick<br type="_moz" />

RE: Silver Swallow Pulldown
 

Photo's please :D

RE: Silver Swallow Pulldown
 

They should have one at work somewhere ( camera )

Ive got the plane 1/3 built

I dont mind the Silver Swallow at all,, the crank is pretty hard so is the cylinder, to me it looks like a classic Diesel

The good thing about the 1.49 is that you can have a lot of flights on a small amount of fuel , and when you tune them up a bit they rip

RE: Silver Swallow Pulldown
 

I can only take 0.6 grams out of the piston because you cant get the piston pin out, its a pain that way


The rest of the motor looks like it will run,,,,,, the contra is quite tight but , I will free that up

Slowly building it up

I will use an 8x6 as that heavy piston wont like to rev

Piston and rod and pin are 6.8 Grams

RE: Silver Swallow Pulldown
 

Hi
Its a no go , was hard to start and real loose when its hot , and had corrosion in the bore , I will try to make some parts , will take a few weeks

RE: Silver Swallow Pulldown
 

I made a few parts for it , , a piston made out of mild steel with a 2.5 mm piston pin,,,, down from the stock 3.5 mm piston pin


Next a new rod , pretty thick,,,,

and a mild steel contra piston

Runs OK on the bench on an 8x6 , doesnt start all that well , is a bit leaky , but not too bad , its flyable

I put another tank through on the bench and it starts up from cold not bad,

Compression is still there, pictures when I get a Camera for Christmas

RE: Silver Swallow Pulldown
 

One problem its got ,,,,,,is that the cylinder is not square to the shaft,

the crankcase casting is machined crooked

also the bore is not true to the threads on the outside of the cylinder

I have a spare crankcase thanks to Fiery , I will set it up and take some measurements

RE: Silver Swallow Pulldown
 

Got a Camera
Here is a picture
I will look up the expansion of steel and Cast Iron

My next step before I fly it will be to machine the crankcase a bit truer and lighten the rod up near the piston pin as its too thick , I might check the inlet timing and see if I can make it similar to the Fora Junior timing , Make an exhaust collector ring, grind some weight off the top of the cylinder Machine down the spraybar to get a bit more airflow , Smaller prop as the piston is quite light, it will rev


Its not as lively as my first Silver Swallow 1.75 cc engine , it needs a stroker crank with lots of weights in to match that one

RE: Silver Swallow Pulldown
 

I discovered the secret to flying 1.5cc diesels ,

Build real light

I used 0.7mm ply each side of 1/4 by 1/4 bearers, with a 1/4 balsa profile fuselage

and a foam core wing, covered with brown paper ,with a half span 1/8 th inch thick spar that has 0.7mm ply on each side of it

.008 thou lines about 42 feet lonf with a light plastic handle

And I use a 2.4mm landing gear music wire with a 2inch electric lightweight wheel , i will go to a 2mm piano wire leg as its real light and it will bend a little each landing , but that is OK

And I use 1.5mm pushrod wire with a middle brace to stop flex , it really motors around for a tiny diesel

and real tail heavy so it reacts fast

And I use 2.5mm bolts to hold the engine in with an Aluminium prop washer

Not to mention carving away internal motor parts such as the cylinder, and other parts and lighter contra piston and piston and hollow tommy bar

RE: Silver Swallow Pulldown
 

Nice work there 123Cat!

Let's see the engine installed in an airframe in due course

RE: Silver Swallow Pulldown
 

My latest try was too hard to start , too much leakage past the piston, so out of these parts, I will try again

Its what the Silver Swallow R/ D department looks like

RE: Silver Swallow Pulldown
 

No lack of meat on the piston skirt :)

RE: Silver Swallow Pulldown
 

It must be the thickest piston in the world , I make mine paper thin and the last one went out of round&amp;^^%$

and started rubbing a bit on the skirt but it was just loose,,,,, so hard to start

a gas seal is so hard to get , but I will keep trying ,

Im looking for a place on the Silver Swallow works team<br type="_moz" />

RE: Silver Swallow Pulldown
 

I have it on good authority that their efforts earned them places in a Chinese Government Gulag somewhere beyond the Great Wall in Central Asia.

:D

RE: Silver Swallow Pulldown
 

I started to mod the No2 Silver Swallow today and thought I would start with a 32 mm long conrod first , the stock rod is 21 mm long

Im going to build the rest of the engine around this rod , it should be done on Monday


Picture of the No1 Silver Swallow

Chinese Power

RE: Silver Swallow Pulldown
 

Nice. Is the tube attached to the exhaust collector for priming?

RE: Silver Swallow Pulldown
 

You know when I just quickly read this post I immediately thought you were going to modify a Rivers Silver Streak,
a classic 2.5cc British diesel somewhat inferior to the Oliver Tiger.

I was on the verge of tears!

Rather than rebuilding a Silver Swallow around a 32 mm conrod, why don't you place it on the back of a decent metalworking vyce
and break it into small pieces using a one pound ball pein hammer.

You could then use your impressive technical skills to make a scratch built home made diesel.

I have collected a number of construction articles for such but lack your talent.

I can forward same on request.

Ray :D

RE: Silver Swallow Pulldown
 

No,,

its a lttle exhaust pressure to the uniflow line , I found it gives a good run that way
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RE: Silver Swallow Pulldown
 

Thanks very much , but no

I got the idea looking at high rise buildings, then looking at my Silver Swallow conrod , bigger must be better ???????
<br type="_moz" />

RE: Silver Swallow Pulldown
 

You are going to build a new engine with a rod modified to half as long again?

I am sure that it is possible but tell me how you are going to get the primary compression ratio back to anything near 1.6:1?

You are bound to increase the volume below piston by a relatively huge amount by raising the piston crown's hieght.
And how would you space the liner up by 11mm, that is a massive amount for such a small engine!

RE: Silver Swallow Pulldown
 

Ive got the cyl spacer half made, that is the bit that fits the crankcase , and the rod should come on mon , give me some time it might come together





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RE: Silver Swallow Pulldown
 

So far so good , few more parts in a couple of weeks