Freelance 3/4” traction engine

Nice!

Coming along well  nice family pictures 

Hi Chaps,

Like most folk I tend to have too many things on the go!

I’ve come back to finish the boiler and cylinder mounting and setup 😁

A bit of advice just on pressure testing needed !

I have a sealed boiler up to 100 psi on a slightly scuffed set up but it works…I have brought a reasonable quality hydro tester which I haven’t hooked up yet but can make an adapter for it to work, Question is should I take it further and go for say 150psi and run the boiler at 75psi? Would a higher pressure yield any real world benefit?

Cheers R !

Some pictures 😁

The bronze ring fits the od of the boiler and will be trimmed to a minimum for the cylinder mount to solder to, The mount goes between the cylinder and valve chest,I will reduce the width of the cylinder and valve chest as much as possible!

hi just a thought,  are you using bronze for all the boiler flanges to reduce the risk of dezincification if using brass ? looking good ..I built a boiler about 50 years ago and used brass throughout  which means i can never get a boiler certificate for it ?!  This was built along time ago when there was no club or internet or phones available to advise !! the model was the 440 County Carlow.. so it remains unfinished...sadly

Willy

Hi Willy,

The boiler itself is all copper and rivets too, The bushes are bronze so all good 😊
It’s a shame your one had brass in the build as you say not ideal although for personal use it would e ok for quite a while especially if drained after use……. Mamod ect are brass…. But low pressure 20psi I’m not sure on a pressure limit for brass shell boilers !

Cheers R

Here’s a short video of the boiler under steam testing….

All went well with the hydraulic test up to 150 psi, I decided to go with the design spec here , Yes it did distort once as the design said, I measured across the boiler and chest did not change which so far it hasn’t.

Known faults :

I set light to one of the plastic valve discs lol 😂
Slight leak to the steam output turret , probably so small lime scale will fix that
I ran very low on gauge glass and it currently only just bridges the gap


When I tested the boiler up to 150psi I had left my fixture bolt through the turret as to eliminate all the top fittings, This was later drilled out and then I could concentrate on separate testing of the fittings at 3/4 working pressure to fix any leaks which I had a few small ones prior to nipping things down fully

Onto how to fire this ? I used a blow torch to get 60 psi then lit the little meths burner , No blower installed so it struggles a bit , But it did hit 75 psi (no engine yet) So coal is an option as I found a grate

Other option I’m open to is making a meths burner and trying again with a blower and fire hole door fitted !

Cheers R

Here’s the obligatory loose assembly!!

Cheers R

Looking great!

Excellent progress! 

Kim

Cheers chaps !

Here the gear set complete 🙂

A good mile stone out of the way , It took a bit of set up to get each meshing nice and quiet, The crank gear will be finally set when I make the bronze crank bearings

Cheers R

All the gears look great!  Lovely work there 

Kim

What kind of rubber is the tire on the wheels? Any issues with heat from the boiler?

The tyre rubber is nitrile…

It may well not be great but a bit of an experiment! I have got wheel rims but not spokes and I knew I’d get bogged down making a set …. Maybe one day !

The rubber isn’t fully finished and trimmed yet too 😁


Cheers R

Here’s the crank set up on two almost fully split GM bearings…

I just slit sawed almost all the way with the correct thickness blade to allow the blocks to slide onto the frames , Drilled and reamed for the crank , All turns over well

There was a little void in the flywheel casting so I filled it with JB
Next I’ll make the cylinder mount and then eccentrics


Cheers R