Most Interesting swarf?

Being a novice, i'll not have seen a small fraction of what some of you have.

Any particularly interesting swarf you've noted in the course of your hobby/ vocation?

Be it odd materials or a material/ tooling combination.

Thus far i've been intrigued by~ "Vertical shear tool" on pretty much any material~ hair like filaments, brass included.

Sharp 135 deg drill plus brass~ comes off in pencil shaving~,not your usual tiny chips.

And finally this week. I machined phosphor bronze for the first time.

Not very novel for most of you i guess, but i love the tiny 'springs' of swarf & was quite suprised at just how nicely it machined in the lathe.

I think bronze is my new brass.

"Love" was not Word Of The Day when in turning a piece of phosphor-bronze on my Myford ML7, most of the swarf fell safely towards me but one long spiral secretly wormed its way round and into the motor, shorting that, expensively damaging the 3-ph inverter and knocking out all the power in the house.......

Probably the most interesting swarf would be magnesium, when it catches fire.

HDPE plastic. One long string that wont break , wrap around nightmare. For rough cutting I resorted to scoring lines on the part to get a break.

Form tools can produce some interesting swarf like this which is brass cut with a half round form tool

Again brass this time being reamed with a home made reamer

Hard brass only really produces the shower of fine chips using a traditional flat topped tool, go at it with a **GT insert and it comes off in curls

Aluminium makes really long strands that set off running down my shed

But definitely plastic, I ended up with a huge tangle looking like a drag artists wig

Titanium. You get lots of interesting bright colours if it gets hot, and even more bright and interesting colours as well as many swear words when it catches fire! 😬

The ultimate blow to my pride was a friend who thought my favourite hobby was making swarf. Shown a workshop full of equipment, he noticed a large pile of metal shavings on the lathe, but not the finished item in the chuck!

Later, after explaining I could cut threads, he picked up a DIY store bolt and said "what, like this?"

In the past turners competed to see who could produce the longest length of unbroken swarf. Great fun, but after about 1950 Industry realised it was better to chip-break swarf rather than allow ribbons. So particularly with Carbide, production machines produce sprays of chips, often smokin' hot because coolant isn't used. Less horsepower needed to remove hot metal, the chips are easily handled, and the scrap value of clean metal is higher than swarf soaked in cutting fluids.

I hadn't thought of swarf management as a problem until I came across a 'best lathe' debate between two American's on the web. They decided the winner was the machine that made it easiest to remove the ton and a half of swarf it produced each shift.

Flat out, my Chinese WM280 has just enough power and RPM to produce a spray of 'proper' carbide chips, but I never use it that way. The spray is operator unfriendly, which is why machines designed to use carbide efficiently cut inside a closed cabinet. Not sure the thrashing is good for a hobby lathe either! I use my lathe more sedately, happily switching to HSS and letting super-long ribbons of swarf form. They're quite therapeutic...

Dave

The traditional way of controlling that spray of small brass chips off an HSS tool is to tear the side out of a cardboard fag packet, pierce a hole in it with a pen and then force it over the toolbit so it makes a small chip guard right next to the cutting tip. Works well.

Castellated swarf:

And formed swarf from an insert parting off tool:

Andrew

This is my favourite piece of swarf . While boring out a pulley it decided to feed itself through the lathe spindle and down into the swarf bucket which was on the floor next to the lathe.

Rod

Back in the 70s I was boring out the centre bobbins for National Coal Board cable reels - IIRC it was 8" o/d, 6" i/d steel tubing, and I had to bore it to just under 7" i/d. I had a 2" square section boring bar with a 1/2" square shank brazed carbide toolbit, on big Binns & Berry lathe.

I ground a curved chipbreaker attempt on the carbide tip, hoping to produce piles of easily-handled small chips - but the steel proved too ductile for that, and I wound up using my swarf hook to get the tight spiral that actually resulted to pass out the ar$e-end of the spindle.

The longest tube of tight spiral I got was 32 feet long, but it broke as I tried to pick it up so the surviving length was 21 ft. I gave it to a mate who was an experimental engineer for the textile industry (we still had one then), and he was going to use it to armour a cable until he saw how sharp the inside of the spiral was. He ended up pinning it to a board in an Escher design.

He died 9 years ago, but I think his son still has it.

Lee, what I now do with plastic is mill as much of it off as possible before turning it to final size and shape. You can waste so much time repeatedly stopping and clearing the tangle then restarting otherwise. I can switch my A axis on my mill from stepping through to a position to continuous rotation and it comes in handy for this. Vacuuming up small chips is much easier than clearing a tangle of plastic. A recent job I did included this step and the final profiling had a step where a short stop after I was past the edge broke the tangle then the rest of the cut sent the ribbon flying in an arc like water from a hose and fell on the floor in an easy to collect heap. I took videos of this flow off the cutting tip but have not posted them anywhere yet.

For anyone who is wondering, I did not do the whole job on the A axis as, from past experience, the surface gets ripples that look like chatter if you do not get the RPM of the workpiece, the RPM of the cutting tool and the feed rate in the sweet spot. Leaving a machining allowance of 0.5mm - 1mm leaves enough for cleaning up to a smooth finish.

Here is picture of flying ribbon of swarf when cutting Oilon, this was just cleaning up the outside diameter and in the background you can see the tangle from facing the workpiece and boring the centre.

Martin C

Edited By Martin Connelly on 30/01/2023 13:03:49

A 12” inserted tooth facemill with a 100hp spindle drive produced most unfriendly blue chips on a Herbert Ingersoll planomill. Strategically placed steel screens were required to control the spread of chips and shelter the operator. More interesting chips were created by the Stirk planer with a single point tool, hot chips of crushed steel were produced, a single chip would just fit in your hand after it had cooled of course.

Mike

Hardly in the same league as a giant industrial machine, but I found my carpet had grown thorns after I'd used my Drummond manual shaper on mild-steel, producing tiny, crescent-shaped chips with very sharp points.

To make it more fun the carpet was in bare feet territory, on the small landing between stairs, bedroom and bathroom.

...

On long cuts when turning stringy material, I back the tool off at intervals to keep the swarf length down a bit.

H

They're auditioning for the role of the Tin Man in the Wizard of Oz.

Sandy

Bloke on the right looks like he is the elf from safety.

Paul.

Having seen the photo before they still remind me of Bill and Ben the swarf flowerpot men

Now that’s what you call a roughing cut !