huh?? I ordered a pack of blades for my Dremel saw max. It uses different types of blades depending on the material that you are cutting. The WOOD/PLASTIC and TILE blades are normal with nothing unusual about them. But and however, the METAL, and MASONRY blades all have expiration dates! The metal ones say "Do not use after 6/2019." And the masonry ones say the same but the date is 4/2020. I can't say that I've ever seen saw blades with dates on them beyond which they can't be used! I guess the message is "don't stock up!" What next? Expiring drill bits?
Don Merz
Well, that's the first I ever heard of an expiration date, and I used to do quite a bit of steel fabrication and metal work back in my earlier days. To be fair however, I have been out of that loop for several years now. Out of curiosity, I've spent the last hour or so trying to search into the matter on the internet.
Unable to find any super-definite facts and figures as of yet. But what I have been able to surmise is, the resin bonding agent used in the manufacture of abrasive metal and stone cutting wheels can start to deteriorate after a few years. And I'm not sure what this quite means either. Does the resin just start getting brittle after awhile? That would be my best guess for right now, anyway.
Something else I found, if the abrasive wheel has fiberglass reinforcing mesh bonded into it, then the expiration date is 3 years after the date of manufacture. If there is NO reinforcing mesh in the wheel, then the expiration date drops down to 2 years.
Also mentioned was that if the wheels are stored somewhere where they can get damp, that doesn't do the shelf life a whole lot of good. I have to wonder if that dampness may include the humidity we can get throughout the year, but no information I found elaborated on that.
Expiration date or not, one should ALWAYS wear protective eye wear, face shield, and clothing when using abrasive wheels. When cutting metal, they throw hot sparks. If they explode, they just throw chunks straight out from the spinning shaft. Always keep your face out of the potential explosion path of wheel fragments, and your body too if at all possible.
Personally, as for myself, and considering my past experiences, I would continue to use abrasive wheels even if they are outdated. But that's just me. Unless others have my kind of experience, I would encourage them to heed all the warnings and expiration dates.
Paul