Looking for Carbide Education

[ragswl4]

I have been looking at router bits and many of the ads talk to the type of carbide used on the bits. I have seen C2, C3, and C4 carbide mentioned. Also one ad indicated the carbide was K10 or K20. Any insight into this subject is appreciated. I think I got it that C4 is better than C3 is better than C2 but don't know why. Thanks.

[LCHIEN]

http://www.bt3central.com/showthread...carbide+grades

from a couple of years ago. Discussion of C grades and other factors.

I think K is another grading system, maybe European...

All other factors being the same, C4 is harder than C3 which is harder than C2
but C4 is more easily chipped by impact than C3 which in turn is more easily chipped than C2 etc.

Harder means that it will get dull slower from use, but
carbide also has grain characteristics, finer grain means it will get wear more slowly. So a finer grained C2 might wear better than a coarse grained C3 even though the C3 is harder. And the C2 holds up to impact better (less likely to chip). But finer grained carbide is probably more expensive.

Most WW tools are C2 or C3, C4 being too brittle and C1 being not hard enough.

So the answer, it's not just all about the grade. You're probably better off going with a reputable manufacturer rather than strictly by grade.

[Knottscott]

I don't know much about the carbide process, but I do know that C4 is harder but more brittle, takes a sharper edge and tends to hold an edge better, but it's not always a "better" choice. In situations where there's lots of impact, C3 can be a better choice...like with rip blades. C2 to C4 all have appropriate applications as wwing cutters.

[cgallery]

Great question. I've seen the same Q on other forums. It would be nice if some of the magazines would run more technical articles on topics like this rather than more "router bit shoot-out" types of articles. Then perhaps we could ask manufacturers whether they used C2? C3? C4? And we could make more direct comparisons.

I'll follow the thread from Loring, too.

My own quest for router-bit bliss has been hampered by my absolutely cheapness. I have a hodge-podge of bits right now. I use mostly straight bits the most, with some simple profiles (roundover) and maybe a slot-cutting bit or two.

Every time I think I'm ready to commit some $$$ to higher-end bits, I add-up what I'll need and I get to $100 to $150 pretty fast!

That always provides an incentive to soak my current bits in a little 409 and clean them up. Then I take my diamond CC hone and touch them all up. And then they start cutting like new and I forget about it.

I guess one thing that has really stalled my on my desire to replace bits is not knowing the longevity of higher-end bits. If I have to sharpen my current bits after fifty feet of composite (MDF or plywood), how often will I have to sharpen those Whiteside bits, for example? Rhetorical question. I know it is hard to answer.

Another issue: I early-on purchased a Forest WWII blade. Was very happy with it. When it finally dulled to the point where I had to send it out for sharpening, I purchased a Freud Diablo blade. I am also very happy with it. Only, the Diablo was 1/3 the price of the Forrest! I'm not saying buying the Forrest was a mistake. But in hindsight, I don't think I would buy it again.

But am I blathering. I've had too much diet cola. I apologize.

So this last week I needed (wanted) a spiral flush-trim bit. I ordered from Holmbren a Whiteside 1/4" upcut spiral with bearing. I ordered the bit on Monday. With the BT310 code, I got it for about 20% less than anyone else was selling it. I got free shipping. I'm in Wisconsin, he is in Florida. I got the bit two days later. Tell me how that isn't a fantastic deal.

The Whiteside bit cuts nicely, and I'm very happy with the result. When my cheap bits finally do start to wear out, and I start to replace them with (perhaps) Whiteside, I'm going to make sure Holmbren gets my businesses. This was my first time dealing with Holmbren, and I was very impressed.

[ragswl4]

I've switched solely to whiteside for bits that I know will bet heavy used, such as door panels, stiles and rails that I need to make a lot of. I have purchase 3 whiteside, all from Holbren. As you said, best deal, best service.

[siliconbauhaus]

I've never used a router yet....eek

I got one of the tritons off of jeff and a set of bargain bits from Holbren.I'm going to learn the ropes with them and then go back to Holbren for some Whiteside ones as and when these wear out.

[Uncle Cracker]

Can't beat the Whitesides, but I've also had excellent luck from Holbren's bits. I also really like the Freud joinery bits I got from Peachtree at a WW show. There is no question that better bits will make up for an average router better than a great router can do for cheap bits. Given the choice, spend on the bits.

[Holbren]

This link will clear some things up and maybe create more confusion.

http://www.tigra-usa.com/cms/product...orking/grades/

The C3, C4 .. ratings were created by the US carbide companies where K10 and K20 are ISO (International Standards Organizations) ratings. You'll notice on the page I referenced, that company specializes in carbide for woodworking and make their own recipe's best suited for different jobs.

[ragswl4]

The C3, C4 .. ratings were created by the US carbide companies where K10 and K20 are ISO (International Standards Organizations) ratings. You'll notice on the page I referenced, that company specializes in carbide for woodworking and make their own recipe's best suited for different jobs.

Great reference, Thanks.

[cgallery]

This link will clear some things up and maybe create more confusion.

http://www.tigra-usa.com/cms/product...orking/grades/

Yeah, that is a useful link. Just a week or two ago I read a comment from an "expert" (on another forum) that said there was no difference in carbide. That is all came from four different plants around the world and it was all the same. I remember thinking at the time, "it can't be that simple, can it?"

Obviously it is not.

I wonder, BTW, what magnification they use on that page to show the grain of the carbide samples. Anybody wanna guess?

[Holbren]

I wonder, BTW, what magnification they use on that page to show the grain of the carbide samples. Anybody wanna guess?

I say 1500X