Red Teflon Coating (RTC)

[Tom Veatch]

... has been mentioned a couple of times in another thread (http://www.sawmillcreek.org/showthread.php?t=94132) as possibly being endangered by various blade cleaning methods and solvents. I post here to avoid hijacking that thread. Can anyone state conclusively that the coating is of any benefit whatsoever beyond being an advertising gimmick?

I know that teflon is a non-stick surface and may have some anti-friction properties. But the RTC blades I own all have carbide teeth that are wider than the blade disk. Since the disk is appreciably thinner than the kerf, the disk doesn't contact the workpiece making any anti-friction properties of the RTC immaterial. Nor have I noticed that the non-stick property of teflon has much, if any, effect on pitch and gum buildup around the teeth when compared to my blades that do not have the RTC. So what's the big deal if the RTC is removed by the cleaning process?

[Tom Henderson2]

Hi Tom-

Good question, and one I've often contemplated.

Seems like I've seen marks on the side of some of my blades, though, that would indicate that the wood is contacting the coating. Dunno if it is just reaction wood, or offcuts that get sucked up along the blade, or what.

Hopefully somebody that knows will chime in and educate both of us.

-TH

[jerry nazard]

Right off, the only obvious benefit I can think of is protecting the blade from rust.

[Jim Becker]

Since the coated portion of the blade shouldn't be in contact with the wood during cutting if the machine is properly set up, the coating largely makes for easier cleaning over time, etc. IMHO, of course.

[David DeCristoforo]

The following is quoted from CMT's web site:

"Teflon® coated blades stay sharper longer - In woodworking tests, the Teflon® coated blade cut 55% more linear feet of wood than painted blades and 50% more than chrome-plated blades.
Teflon® coated blades are rust resistant - In accelerated tests, the Teflon® coated blades effectively sealed out moisture that caused painted and chrome-plated blades to rust. No oils, greases or rust-preventatives needed.
Teflon® coated blades clean up easier - The non-stick nature of Teflon® makes blade clean up easy. Even after extensive use, Teflon® coated blades wiped clean of gum and resin build up.
Teflon® coated blades use less energy - Ammeter readings taken from a 7-1/4" circular saw proved that Teflon® coated blades used 38% less amperage than painted blades and 35% less than chrome-plated blades. By using less amperage, Teflon® coated blades can help save wear and tear on saw motors and reduce energy costs.
Teflon® blades perform smoother, sharper cuts - In tests conducted in wood, Teflon® blades did not gum up or collect resin like normal blades do. The self-lubricating Teflon® finish sheds sappy wood residue before it builds up and leaves the blade clean to make sharper, more accurate cuts."

It would seem that much of the claimed advantage of the coating has to do with cleaning and rust prevention. The claims of lower amperage usage and staying sharp longer? I have a feeling that these claims should be followed by disclaimer similar to that found on most nutritional supplement containers "These statements have not been evaluated by the...etc..."

You are correct in that in an "ideal world" the blade body "should" never be in contact with the material being cut. But this is not often the case. Any slight movements of the wood during the cut or deflection of the blade or runout of the arbor could cause the blade plate to contact the wood. These possibilities are much greater with thin "kerf blades". Also, with many blades designed specifically for use in crosscutting saws, the "overhang" of the teeth is minimal, further increasing the possibility of wood/blade plate contact. So the coating probably does have some positive effect.

Personally, I think the main reason for the coating is so that manufacturers can have their own "signature" color. Freud started the whole thing with the LU85M which was coated with jet black teflon and became known as the "Darth Vader" blade. The others soon jumped on board.

[glenn bradley]

I thank David for covering that so well. I have a few marks on some blades where loose slivers or super-thin pieces have rubbed. Mostly the coated plate stays clean but does seem easier to get back to clean when required. My non-coated plates get T-9'd or waxed after cleaning.

Anyone who has dabbled in mortar, paint or other cumulative material knows to keep their cutters extremely clean. Once that one little piece of crust gets missed, other unwanted material grabs onto it and snowballs at an alarming rate. This keeps me in the mindset of cleaning things up now and again ;-)