Procedure for die polishing

A. For round shaped carbides a first grinding operation with diamond rotating stones (will leave about 16-32 RMS), then different grades of diamond blocks that work with lapping devices. The punch is mounted in a lathe and is rotated while the blocks travel across the surface at high pressure and speed (8 RMS), then a final luster with diamond paste (4-2 RMS). High speed steel can be polished in the same way or with more traditional abrasives (stones, sandpaper, diamond paste, etc.). Squares and complex shapes are very peculiar and cannot be described here so I strongly recommend that you hire a professional.

A. How big and heavy are the dies? If your dies are smaller than 12 x 4 x 4 and/or less than 2 lbs each, they can be run effectively in a mass finishing system using treated dry organic media.

A. Follow up for Guillermo. I have a book coming out soon which covers this subject and have written several articles on this; however, to give you a little more info, this is what I can tell you. Most dies are made of very hard steel alloys. Once they are made and after use, they can be polished using a dry organic pretreated mix that has alum. oxide rouge. Surprisingly the parts clean up (mostly carbon type deposits) relatively easy and normally look like a piece of jewelry after 24 hours in a small vibratory mill. Shorter time cycles are acceptable down to maybe 8 to 12 hrs. Not sure how well other contaminates might work. Down side is long time cycles and if too many pieces or too heavy of parts are batched this might cause part on part contact and damage.

A. Many carbide and tool steel punches are turned to a 6-10 rms finish, then polished with diamond polishing compound to a 0-2 finish. We sell CBN and PCD tools for turning these types of materials, our customers will commonly polish a 2 7/8" diameter punch in 5 to 8 minutes using buffing wheels and diamond polishing compound. Hope this helps.

A. Ghulam,

Proper mold polishing is normally done using finishing stones to polish the mold itself. I prefer Boride brand polishing stones and using Bori-lube 10 as a lubricating fluid. The stones come in different sizes, shapes, and grits. Process is straight forward, but patience is key. If dimensions are not highly critical (plus or minus 1 thousandth of an inch or so) then anyone with alot of patience and good hands and vision can polish the mold. If tight tolerances or extremely fine detail are involved then it is usually done by a highly trained and experienced specialist.

--Rama