scrap truck shop metals for rocket heater (newbie)

I have found and think I have access to a heavy duty truck ship. they have a lot of 18 wheeler truck rims, wheel drums and exhaust pipes. Looks real good to integrate into a rocket heater. does this sound like good metal to us to transfer and store heat. I know my terminology may not be correct. I have been interested in rocket heaters and this looks like good material to use?

thanks,

Hi Mitch; Welcome to Permies!
Some of the things in a truck shop might be of good use in a mass. The barrels of course are handy, especially if any have a removable lid.
Heavy steel / cast iron in your mass is good, although odd shapes must be carefully filled with smaller heat retaining items and all gaps filled with cob.
No air spaces allowed in a mass.
The exhaust pipes are most likely to be of to small a diameter.
Good things to search out are used fire bricks and regular plain clay bricks.
A 50# sack of  fire clay as mortar.  Stove pipe of, 6" or 8"  regular and HVAC.  
A source of clay.  Sand , not from the ocean.  

GM, thanks for the reply....good info