PDA

View Full Version : Satin finish



Rotate
02-26-2002, 05:16 PM
How do you create that nice satin finis on steel that I see on finished products. After turning or endmilling, I'm always left with machined finished. I've tried using sand paper with limited sucess, especially on flat endmilled surface. Thanks for the advice.

Albert

KACHINKOO
02-26-2002, 05:56 PM
GOOD QUESTION ROTATE. MOST HSM DON'T KNOW HOW TO PUT A FINE POLISH ON MUCH, SO HERE IS A QUICK RUNDOWN OF HOW I DO IT FOR A HIGH POLISH ON STAINLESS.
START WITH A GOOD SOFT BACK GRINDER AND SOME 60 GRIT FOR RAW METAL ,OR 120 GRIT FOR MACHINED SURFACE. WORK YOUR WAY UP TO 220 GRIT REMOVING SCRATCHES FROM PREVIOUS GRITS. (60-80-120-150-220) THEN 220 GRIT SCOTCHBRITE TO GIVE YOU THE 'SATIN' LOOK.IT LEAVES A NICE UNIFORM SURFACE FROM WHICH YOU CAN CONTINUE WITH POLISHING COMPOUND AND A GOOD BUFFING PAD ON A STATIONARY BUFFER TO GET A MIRROR SURFACE. PRACTICE AND EXPERIMENT, A 2200 RPM GRINDER WITH A 5 INCH SOFT FOAM PAD FOR STICKY-BACK DISCS FROM 3M IS WHAT I USE. A ONE FOOT SQUARE CHUNCK OF QUARTER INCH STAINLESS STEEL WILL TAKE ME ABOUT HALF AN HOUR TO SAND AND ABOUT HALF AN HOUR TO POLISH. IT IS NOT HARD WORK BUT THE RIGHT TOOLS AND TECHNIQUE ARE KEY. GOOD LUCK, KACHINKOO P.S.YOU WILL REMOVE SOME OF THE SQUARENESS FROM THE MACHINING!

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

Rotate
02-26-2002, 10:47 PM
Thanks for the info. What do you mean by "soft back grinder"? Do you mean use an angled grinder with flexible backing where the sandpaper is attached to?

Albert

Thrud
02-27-2002, 02:24 AM
Albert
A satin finish is easily attained by glass bead blasting. The green 3M pads your wife buys for the kitchen can be put in a Random Orbital Sander and give you this finish quickly if the surface is smooth to begin with. If you use a regular orbital sander it leaves tiny circles in the finish exactly the size of the sanders orbit diameter. The Random Orbit Sander is the key to a fast gorgeous finish in autobody, woodworking, and metalworking. Try it out on scrap first - experiment a little to find the surface finish you like best! The 3M pads can be bought in may different grits, but I find the kitchen pads give a nice frost for a lot less than the industrial pads.

Normally a tool & die maker will polish in 30 grit steps to reduce the time required between each grit (going to too big a jump in grit causes excess work time with that grit). Unless you desire a gage block finish, don't bother going past 1000 grit. For a cutting edge a final hone at 3000-6000 grit (Chromium Oxide and Japanese "gold" Waterstones) is great for knives but not necessary for lathe tools. Diamond abrasives cut faster past the 1000 grit stage and can be used to put an Optical Quartz Flat finish (+-.ooooo1"/ft)to metal. Most granite plates and Jo blocks are accurate to +-.oooo50"/ft flatness.

Dave

Rotate
02-27-2002, 05:35 PM
Thanks.

Will try.

Albert

snorman
02-27-2002, 07:04 PM
Most likely that satin finish is the result of finishing with a surface grinder or for less critical parts with a belt sander.