I think heat treatment to stress relieve is a fairly modern idea to speed up the job. Back when Stephenson was a lad (well maybe when his grandson was a lad anyway) new castings as you probably know we're chucked out in a field to weather, brought in and part machined and stuck back out to grass before final machining and finishing. All of this you are probably well aware of! This was still considered to be the way to do it when I worked for a large marine diesel manufacturer in the late 90's (probably though because there were few facilities big enough to take the castings anyway!) Obviously you want to use your camel back before you are too old to pick it up though, so that approach is probably not going to fly! I doubt though that the domestic oven will do the trick, better bet might be an aquaintance with a pottery kiln or similar. Best bet if you want a professional job is to find someone on the inside somewhere that can slip it in with something else. As you say most big companies view the likes of us as a pain in the backside so quote telephone number prices to discourage us!

Paul.

The last time I got something stress relieved (about 30 years ago) I was able to go to a local heat treatment company (in Loughborough) and get it put through with a batch of something else. If you can find a company, it costs nothing to ask.

Martin

Not sure if BBQ charcoal would get up to the required temp to get the casting up to cherry red heat, unless you add some kind of blower like a hair dryer etc to up the ante a bit. But I have never tried it so there is only one way to find out…

Where I worked, in Leicester, castings were kept outside. But this was in the days of reasonable volumes when buying a 100 or so of a part was no big deal. Move on twenty years and small volume and single castings, heat treatment of castings and fabrications. Lastly over the last years some vibrational stress relieving of fabrications and machining from solid rather than casting.

There's no point scraping the feet THEN stress-relieveing it because the scraped faced will need doing again afterwards.

If you're going to do it – rough-machine it, stress-relieve, machine again then either scrape it or do another round of stress relieving and machining then scraping. Forget fire pits and barbeque tricks for a reference surface like this, take it to a professional and have them heat soak it in an oven so it gets even heat all over then controlled cooling. Anything else is just rolling the dice and hoping.

Personally I would have liked to see a lot more thickness on the sole of the one in the pic above. It's going to be very thin once it's machined past the skin.