Hot lathe chips

Nice lathe, Neil.

Having the ability to drag this topic further from its original title, at some time around the 50’s, a likeable old chap called Fred joined the toolroom and put in charge of the 24” shaper. There was a story, perhaps invented to impress us apprentices that he had once worked for RR.

Already in his 70’s, he was heavily into chewing tobacco. Some of the lesser respectful, suggested that he had an A/H at both ends. Even worse (?), especially for the labourer who had to sweep up everyone’s swarf, he regularly aimed his excess spittle into the pile of chips building up in the guard surrounding the business end of the shaper.

Spittle-quenched chips of blue?

So that I haven’t killed off Ross’s thread altogether, here’s a rhetorical question …

Is the (lathe/shaper/milling) tool cutting or pushing?

Sam

I doubt that insert will last as long doing ten times as many 0.25mm(!) cuts as recommended in the lathe's manual.

Even a mini lathe will take 2mm cuts all day long and my mini-lathe manual says 0.1mm!.

Neil

Now, that might depend on the feed rate as well as the material and the cutter. Probably not a good idea if running slow on a speed-controlled motor while cutting a large diameter workpiece!

But I do agree that a decent workload on the tool is necessary to maximise the amount of material it will remove in its lifetime, or between sharpenings.

Also have to remember that most in the UK set an actual cut depth, but many, particularly over the pond, have the ‘cut setting indication’ as the reduction in diameter for a lathe (yeah, they have different views for lathes and mills - and I do sometimes wonder what they report when taking circular cuts with a CNC machine). So we have to be a bit specific when making claims.

Not necessarily - popular UK machines like the Warcos and others calibrate the crossslide on diameter. Means you have to dial off twice the value when milling in these lathes. I think the Colchester Student I often use down the railway shed is the same.

I did say ‘most’ and unless someone can quote actual figures to disprove my statement, I will stand by my post. And that many in the UK have lathes which dial in half the cut for the value indicated.

That, I think, indicates that the numbers of each may not be so wildly different, but that the ‘real cut’ indicators are the more prevalent type found in the UK.