Hi ,

I will be starting on a hit and miss engine later this year , i picked up the castings from that auction site we all know but the materials for the cylinder liner and piston were not included .

The drawings only state cast iron for both so i need to purchase some cast iron bar to make these but …

I can get 4E grade in the right diameter for the liner and have some 2P grade here that will do the piston and rings .

So what i want to know is :

Will the 4E grade be ok for the Cylinder?

Will the 2P grade be ok as piston/rings running in the 4 E grade cylinder ?

I am led to believe that 4E is slightly softer and a little less wear resistent tha 2P and its structure is a little different ( pearlite v semi pearlite etc )

Up until now my engines have been Aluminium piston in what ever chunk of cast iron i could scrounge for a cylinder and i used thae same suff for rings .

Ian..

Thenks Jason and Ian .

The 2P and 4E seems to be something the manufacturers have conjured up as i can't find anything about what it means and there is the 3D for ductile .

They are both covered under AS & BS as the same classification but they do differ in composition , the 2P has some different elements that make it more wear resistant, they both seem to sit mid scale for pressure rating @ 250 mpa.

I suppose for a low speed model engine that will not do a lot of work the softer 4E will do .

Funny thing about meehanite , from what i can gather it is more about the manufacturing process than actual composition as Wikipedia have as a patented manufacturing process for fine grain grey cast iron .

The engine is a 62 cc Rosebery

Ian.