Adding A Reed Cage ?

[Lightning Performance]

Dave I think you missed your true calling as a writer.

Dave gets right to the heart of it. He not *f-wordin around when it comes to saw races. The BS is a thin veil to troll the competitors. They still bite. Plus he's a fine writer.

Diamond Daves got a new racer on da pipe.

 

[Lightning Performance]

Sick intake Chy I like it.
Sick is good!

 

[chy_farm]

Second carb - bored out with a trickle of nitrous, set to pop open at 90% throttle No choke on carbs

Haven't think of that nitro fuel I used to use for my hobby RC small engines some 40 years ago, But It sounds very attractive to me too, it should be one of my choices, Dave.
As far the choke you see here, yep I an not going to use it.

Ignition set to retard until engine hits 4500 rpms and then advance quickly over a half second.

0.5 second interval... did not know what this means to the nitro-fuel system.

Several of the manufacturers of the program able ignitions offer lite weight flywheels as well.
Big saw with plenty of grunt doesn’t need the extra inertia of a flywheel ---------------Dave

That's a good point too Dave, I have been thinking about the possibility if I will be able to fabricate one with a better sirocco fan that creates higher air pressure. It must be a toil to make one from the begging...

 

[chy_farm]

Sick intake Chy I like it.
Sick is good!

SICK intake? tell me what it means Lightning thanks in ahead!

 

[Chainsaw Jim]

That use of the word "sick" is a slang term for acknowledging something very cool or very impressive.

 

[chy_farm]

That use of the word "sick" is a slang term for acknowledging something very cool or very impressive.

Hahaha, thanks Jim, I tried to look for the abbreviation!

 

[chy_farm]

------ I am going to fabricate a totally new one for this contraption, but only a question is if it goes good to her, ------Chy

I found a couple of nice reports on the proper design of sirocco fan and casing;
[Design and Analysis of Volute Casing: A Review]
http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1694326

A little more complicated one here;
[Effect of Volute Shape and Impeller Outlet Angle on Performance of a Centrifugal pump]
https://www.researchgate.net/public...et_Angle_on_Performance_of_a_Centrifugal_pump

Hope at least one of these could help me out!
Chy

 

[chy_farm]

Been off from this fun job for a week, this morning started it again with some aluminium brazing. Brazing a small fuel pipe.
The carb needs a 6.0mm fuel pipe at this tank side, but I do not have one in the size in my hand.


One in the left was the first attempt with a small failure though, lol.


Gave it some filing.


Seems it fits nicely.


Chy

 

[chy_farm]

Get some time this morning to try out TIG on these aluminium parts.

Have been worried if my skill can manage welding 1.5mm thick alu sheet,

Hand made alu pipe is now welded on the tank wall.

Tank cap came from the McCulloch original.
.
.
This new tank needs a base plate to sit on, so applied one under the tank. Marked with a red circle.


The tanks will sit on it like this.


The original tank cap comes like this.

 

[chy_farm]

The new fly wheel shroud is being welded too,

 

[Chainsaw Jim]

Are both carbs sharing the same fuel outlet barb you welded on? They'll likely fight each other for flow.

 

[chy_farm]

Are both carbs sharing the same fuel outlet barb you welded on? They'll likely fight each other for flow.

Good morning Jim, I did not think of that point. I think it will go OK, but perhaps will need some accelerator to the tank, e.g. a positive pressure. Anyways your point is fun to try consideration Jim!
Chy

 

[Chainsaw Jim]

Good morning Jim, I did not think of that point. I think it will go OK, but perhaps will need some accelerator to the tank, e.g. a positive pressure. Anyways your point is fun to try consideration Jim!
Chy

There's a part from pioneer chainsaw fuel tanks that might help if you end up needing another connector.

 

[chy_farm]

There's a part from pioneer chainsaw fuel tanks that might help if you end up needing another connector.View attachment 104090

Thanks Jim, looks nice and seems it will do a nice job, wouldn't mind one for me/her, lol. Thinking of making one more and adding it to the tank in case she wants more fuel, for an insurance sake lol.

 

[chy_farm]

Did some more welding on the tank, welded the top plate for it.
Also added a air-pressure inlet to it, thanks @Chainsaw Jim !

 

[chy_farm]

[Brazing with HTS-2000 aluminium solder]

Lately I sometimes thinks of a necessity to have skill of jointing a small alu parts to other bigger part of a saw, e.g. a small fuel pipe to a alu fuel tank, etc. But smaller parts are mostly consist of thinner walls of alu plate which does not like dull-hand of a novice welder like myself, lol.

So instead I got this material for brazing alu things. They say HTS-2000 solder does not require any flux, so this sounds somewhat nice to me too. Here are some;


The surface of these rods looks kind of rough compared to e.g. some standard TIG filler rods, looks like the electric solder being chilled in a half-cut small pipe after it got melted and poured in there with free hands. So at the first glance you may not believe this can do a nice job, lol.


This is a small alu box for today's specimen, with 0.8mm thin walls. So this can be one of the examples that can not be done with a standard TIG machine. The walls are too thin to be welded with amperage larger than 20A, IMHO though.


Not so bad, the melted solder easily goes into the gaps and got flattened with a stainless brush.
Better use bigger air-propane torch.

Chy

 

[chy_farm]

[Brazing with HTS-2000 aluminium solder _2]

One more trial is on the small pipe of the alu fuel tank I posted the day before here.

In my latest TIG to this, the butt-joint part got affected a little so that the wall seemed it got damaged a little. Glad it got repaired easily.

Chy

Incidentally a before view is;

 

[chy_farm]

Bottom plate welded.

Leak-test passed.

Added feet to the tank and placed on the base plate.


Chy

 

[Deets066]

Very cool build Chy

 

[chy_farm]

Very cool build Chy

Good evening and thanks.
Chy