Twin marine oscillator

[Team ricky]

Hi Charles,

Yes that’s the port layout I used ….

I’m pretty much decided on no bracket 

Onto a boiler now I guess ! Here’s a pic of the internal grooving tool , this little tool is amazing and can just sneak into an 1/8” hole which is a common size of piston / valve rods on small engines

[Team ricky]

Hers a pic of a second hand not completed Scotch return boiler….

It looks to be wetback but I’ll have a look when it arrives to see if it is or not… most model ones I’ve seen are dry back single pass.

I’ve got a small boiler fully fitted but it’s spirit fired and I’m not too keen on it ! So I’ll take the new fittings I used on that one and build up the Scotch return

It was cheap and obviously comes with the risk the current build is not good but I’ll see , It’s silver soldered so far probably except the smoke box which looks to be soft soldered (no good) Easy fix to de solder that and re-silver solder

[Team ricky]

So the boiler arrived no problem 😉

As I expected from the pictures the front head has been tickled with a bit an obvious leaks along the seam, an attempt to braise was made unsuccessfully

I’ve cleaned off the braise, opened up any gaps and picked , soldered and fixed

Next there is a tiny leak in the combustion chamber rear, about the worst place pollution lol 😂

It is tiny and not structural, it actually stopped when a bit of contamination went over it tested on low compressor air, Because it’s dry back as expected I can use the loctite trick to draw a tiny bit into the void ! Bit of luck needed but I have very thin post application loctite which is perfectly suited to this type off job


I did just have another thought… it’s possible to fill the wet side of the back head with rosin flux and solder at the end of the job (post bushes) and heat it in place with the boiler up right… that will certainly caulk the problem too….

[Team ricky]

This arrangement seems best for the sight glass …

Nice and high and gets a little protection from the smoke box, I’m pretty sure I’ll have to make new holes to suit and blank bush some others I don’t need !

[Team ricky]

Pic

[Team ricky]

Here’s a pic of some progress

I’ve made a Scotch style steam dome and made some bushes ready to solder in place , I decided to go with the sight glass off to one side, pick up on all the existing holes in the side of the shell to feed the gauge, It will be mounted on 11x11 brasss square stock to help it not getting knocked…!

[Team ricky]

Now at the stage where the next silver solder session begins!

I’ll solder up all the bushes and sight glass manifold in one …

Just thinking on the back head leak as to whether opening up the dry back to have a good look and provide servicing access to the tubes …. I’m thinking a hole saw set up in the lathe and fixture the shell to the cross slide ! What could possibly go wrong lol 😂