What's new
What's new

Running Cast Iron

Ox

Diamond
Joined
Aug 27, 2002
Location
Northwest Ohio
Looks like we have a production job of CI coming in this spring.
Nothing fancy - just drilling through holes.

I have never ran cast in a production environment, and specifically try to shy away from it for the most part unless the qty is either really low or really high. I guess this job meets the upper threshold close enough, so it looks like we are going to run with it at this point.

My Q revolves around handling the chips.

Doo you handle them any differently than steel?
This is coolant - so we wouldn't be spinning them - and I can see that plugging up a spinner screen real quick ...

I guess at this point I am just looking to run them into a hopper and let drain, and then dump in big tub outside.

???


-------------------------

Think Snow Eh!
Ox
 
Ox, do you know the grade and hardness of the CI you'll be working on? At least some recommendations will be based on that info.

Some CI's are very small chipping, even "dusty", some more ductile, some abrasive, etc. And as TomB (surprised he's not commented) can tell you, cheap castings may have hard inclusions which can make your day miserable with damaged tooling.
 
Where I used to work we machined tons of cast iron and ductile. Some mills, drills and rotary transfer machines we machined dry. Good cast and ductile did chips really well, some dry dust, poor cast was the pits hard spots and lots of dust. Then we got machining centers and coolant and the dust went down but ci dust would settle out in the corners and crannies and then “set” up, had to chiselsome of it out. The other thing was it would settle in the coolant tank get sludgy and stink. A coolant filter helps keep the fines from recirculating and causing tool problems. Warren
 
Last edited:
This is coolant - so we wouldn't be spinning them - and I can see that plugging up a spinner screen real quick ...
I avoid using coolant if at all possible with cast iron. It makes a nasty nasty mess.

If you must, then you must but get the stuff out of the machine as fast as possible and clean it all up asap. Seriously, try without coolant first. Usually works great.
 
I don't know that I could git away with dry on drilled holes.
That tool would heat up quick.

Could maybe MQL or whatever?


----------------------

Think Snow Eh!
Ox
 
I don't know that I could git away with dry on drilled holes.
That tool would heat up quick.
Depends on the hole and all but I would try it first. Sometimes slow down a little helps ... if those cast iron chips that have been coolantified sit even overnight, they make a porous mass that's really awful, rusts the hell out of everything, is difficult to remove, sometimes makes the coolant shitty, just nasty.

The dry stuff is easy to deal with but globs of hardened cast iron sponge in corners and t-slots and the coolant tank is terrible. Even oil-base coolant is better (but pretty sure you don't want to change over for one job.)

If chip removal becomes a problem you could put in program stops to get in and brush away the chips. I'd rather do that than deal with the mess water+cast iron makes.
 
Ox
I'm in the run dry, run slower, run carbide camp. If you
are enlarging pre-cast holes 3-4 flute core drills work well.
spaeth
 
It not only makes chips it make a lot of powder.
This makes for the "sludge" that collects and all complain about.
It also makes for a big dust control problem if you try to go dry without a lot of vacuum. Everything around will be black in a short time of production runs.
I'd go very heavy flood wet even though the cutting tool may not need it. Lots of flow.
One can also route a coolant line into the tank to flush the muck to one end.

Oppisite side is go dry but your dust collector may need more horsepower than your spindle and then deal with filters and changes.
I do like dry machining or MQL in steel and do it mostly that way but CI in volumes is just so messy.
Bob
 
Plan on thoroughly cleaning the coolant sump when the job is done, if you end up using coolant. It will be like mud at the bottom. Keep your coolant concentration up as the crap will rust into a solid mass and you will need an weld chipper to remove it. Wash the machine down on a regular basis to get any dust off. Its just bad stuff for a machine, but it is what it is.
 
The CI flanges I used to drill on a big G&L radial were easy machining. When using coolant the chips would start rusting before the end of the shift. T-slots, toe clamps, and studs would also show surface rust if left overnight. I only had batches of 5-10 flanges so I chose to run dry and clean up immediately. I used HSS drill and would touch up the drill when hard spots showed up. Old job with castings made back then. Good luck.
 
CI Mess

We machine a lot of CI, and whooo doggie it is mess.
99% of the time no coolant
























































































































































































































































































































































































































































































































































































































































































































































































































































































We machine a lot of CI and it gets every where.
No coolant, a tad of water and you have metal bricks
we use a combo of HHS an carbide depending on the operation.
It i
 
I dunno, I ran Blanchard grinders quite a few different ones, and one was a high production
model with the "waterfall coolant system". Lot's of coolant, and it all sluiced out of the main sump,
out the back, enough flow to keep it moving to the settling part.

Other ones either you "hoed the sump" each day, or it had the drag out system.

I would treat this job much like grinder swarf.
 
This is a continuous job on a transfer machine.
Not full time, but continuous. (supposedly)
Not a one and done.

I think Doug nodded off at the keyboard?


----------------------

Think Snow Eh!
Ox
 
This is a continuous job on a transfer machine.
Not full time, but continuous. (supposedly)
Not a one and done.

I think Doug nodded off at the keyboard?


----------------------

Think Snow Eh!
Ox

No, I'm here.

I suggest running coolant, and treat it like grinder swarf.

LOTS of coolant, to flush or "wash down" the whole machine enclosure, to eliminate those "taconite deposits".

We got those in the Blanchard as well, I spent a couple of hours with a needle scaler inside one.

I was in a local foundry (now defunct) and they set up a large array of Fadals (IIRC) to machine truck brake drums.

DRY.

Ugh, there must have been 6" of dust on top of each and every flat surface, including control cabinets.

IF, and only IF you were going to dedicate to cast iron only, you would do a dust collector dry.

Saw one on a large machining center, lots-O horsepower, collection unit outside, steel piping
4"-6" dia, had large sweeping curves (36" radius), and elbows still wore thru.
 
Cast iron isn't all that bad. It makes a mess sure and we don' do anything special about C.I. chips vs steel chips.
If it's ductile iron be prepared for some serious stank though.
 
I suggest running coolant, and treat it like grinder swarf.
But grinders are specifically built for that. There's no tables with t-slots, augurs, conveyors, or any of that stuff to collect shit. The coolant goes straight down into a sump that's designed to be easy to clean, then nowadays it gets pumped direct to a huge tank with one of those rolling fiber filter things across the top. Grinders go to extreme lengths to deal with this problem ... and THEN the swarf is treated like hazardous waste, which I don't think Ox wants to deal with ?
 








 
Back
Top