machining carbon

[oldben]

as a newbie to hot air engines (built one) I hope to have a go at a low diferetial one and I wonder if there is any special technique for turning carbon I imagine it might be a bit like cast iron.would be pleased for any help
Ben

 

[Tin Falcon]

Ben: I assume you mean graphite. dust respirator and the vac nozzle near the cutter.
Tin

 

[Mainer]

Be a bit gentle on the clamping so you don't crush it. Otherwise, no big deal to machine it. But, it can make a heck of a mess unless you do as Tin suggests -- vacuum hose near the cutter. (You'll still get dust, but it may not cover everything, just a few things. ;D ) And a respirator would probably be a good idea.

When turning, you can take off the last tenth or two by using a strip of brown paper bag as "sandpaper."

 

[oldben]

Thanks guys I had not thought of a respirator must go down to the shops for a brown paper bag they are a bit scarce round here

 

[Blogwitch]

Brown paper not required, try a sheet from your sketchpad, cut into long strips.

It is just like sharpening a pencil when you rub the point on the paper. Same principle, wearing it down gently.

But I would suggest you back the paper up with something like a parallel, in fact anything that is completely flat, otherwise you will have all sorts of undulations worn into the surface.

Bogs