Turning cast iron.

[John Hill]

I am turning down a cast iron exercise weight but it makes a terrible mess!  What are the secrets to keeping this under control?

[sbwhart]

Hi John

Cover your machine with news paper help in place with a squert of oil or grease when done carefully wrap the swarf up in the paper, bits will still escape but it won't be as bad.

Don't cut cast iron with coolant it'll just make it worse, and it'll get between your bearing surfaces and knacker them up.

Have fun

Stew

[John Hill]

Stew, turning a big diameter, about 6", even on the lowest speed sent those grits really flying!  I have it in my hair (what is left of it) and between my teeth!  It was even flying over the back of the chip shield and the window sill where I keep my stock of useful magnets looks like something out of this world!

I didnt try the newspapers but I was careful to keep my brush handy and kept it off the ways and cross slide as I went.   I did not use coolant.

The 'iron' was very hard on the outside and I felt really bad doing the interrupted cuts to get the lettering off the cast.   I am sure there is a lot of carbon and silicon compounds in there but once I got the skin off it was very easy going,  neat sound effects too!  Just a pity about the mess.

[No1_sonuk]

I clean up steel swarf with a magnet wrapped in a paper towel.  Open it carefully over a bin and take the magnet away = swarf in the bin + clean magnet.
I have seen somewhere someone putting the magnet in a bag, then turning the bag inside-out to achieve the same result.

Maybe something like that can help with the cast iron?

[arnoldb]

Also, If you need to use a magnetic base close to it, put the base in a sandwich bag before locking it down.  Even with bases with on/off switches, if you turn it "off" the swarf will stick to the bottom of the base.  With the bag, you can take the base out and no swarf on it. How do I know this ?  experience the hard way - cleaning that swarf off the magnetic base is a  serious PITA.

And the outer skin on CI is the worst; a lot of the time there is still casting sand embedded in it.  Try to take that off with a single deep undercut, else your cutting bit will blunt very quickly.  Then immediately clean the swarf from your machine, as this "first-cut" swarf will cause the most damage to your machine.  Machining the cleaned cast iron, while messy, is less harmful to your machine, but do give everything a thorough cleaning when done machining the CI.

I've found that using a really sharply honed HSS cutter after taking off the skin and using aggressive cuts, produces less of a mess, as the swarf coming of makes bigger chips and less dust.  So far the worst culprit for me with working with CI was doing single-point threading on it - that produces a very fine dust...

Cheers, Arnold

[Jonny]

Sounds like it bothers you John. Its the intermittent cutting that causes that same with turning things like square to round.
Could put a card close by to redirect the chippings.
Worst of the lot phosphur bronze and brass, hate the stuff. Gave nearly all the brass etc away but once had to do a job only 1 1/4" dia x 10" long, putting a cut on and traverse down chippings were travelling 5ft to an internal wall bouncing back another 4ft then sticking in your skin.

For the tough uns dress up, gloves, goggles, helmet, fully done up coat etc

I clean up steel swarf when i can be bothered with a broom and spade.

[Majorstrain]

Hi John,
Have you thought about rigging up the shop vacuum cleaner hose to the carriage so that it sucks the dust away as it comes off the cutting tool.
If you don't have a shop vac, just prey the wife doesn't notice the house vac missing be for you get it cleaned and back to where it belongs.
Cheers,
Phil

[No1_sonuk]

Hi John,
Have you thought about rigging up the shop vacuum cleaner hose to the carriage so that it sucks the dust away as it comes off the cutting tool.

On that note, I have a tumble drier condensor hose that I use with an old Dyson vac.  I got it as a spare from a DIY store (it was Homebase for UK readers).  It's about 1 inch dia.  One end fits the vac, and the other end fits most woodworking* power tool extractor outlets, but it's also flexible enough to wave around to clean up swarf.  Next time I cut some brass, I may fix it near my toolpost.  Bloody stuff gets everywhere!

* Woodworking is like metalworking, but it makes dust instead of swarf.