Do you mean honing or glaze busting used cylinders for new rings?
Honing using AMMCO, Sunnen, or similar?
proper honing oil is best but its expensive (about $130.00 for 5 gal last time I priced it)
I found the synthetic water based machine coolants don't work at all and cylinders get glazed.
WD40 isn't much good for honing, brake fulid works but is messy (and removes paint, messes up pumps, etc) plus, it's flammable.
A good flow of colant is pretty important, keeps cylinder washed out and also cools it
If your just glaze busting, pretty much any type of oil wil work (ATF, used engine oil, etc)
PJ