Burning edge with Freud Glue Line Blade

[Brent Romero]

I bought a Freud thin kerf glue line blade and I am cutting alder wood with the blade and for some reason I seem to be burning the edge of one or both pieces of my cut. I am sure I am making a simple mistake....any thoughts are appreciated.273854

[Jamie Buxton]

When you're part way though the rip, look at the far end of the board. Is the kerf trying to close up? If so, the burning is caused by the board, not the blade. The board is trying to pinch the kerf closed on the blade. The board has some tension in it, perhaps from drying, or perhaps from the way the tree grew.

[Art Mann]

You probably already know this but it is important to keep the workpiece moving at a consistent and fairly rapid rate. I also agree with Mr. Buxton's thoughts. Yet a third possibility is that the rip fence is not set parallel to the blade, which can also cause a pinching condition. I use a thin kerf 10 inch Freud glue line rip blade and I haven't experienced that problem. In fact, that blade cured a lot of the burning problems I experienced using a multipurpose 40 tooth full kerf blade.

[Steve Baumgartner]

While either tension in the wood or a misaligned fence is the ultimate culprit, "glue line" blades are more prone to burning because they get their smooth cut by having very little side clearance on the teeth (that is, the sides of the teeth are ground almost parallel to the plate). The lack of side clearance causes greater friction that in turn causes a greater tendency to burn.

[Jason Roehl]

Feed rate in ripping: slow enough to feel safe, fast enough to not burn. If the blade is dull, or as Steve pointed out, doesn't have much "set" to the teeth, those two ripping parameters may overlap to the point where you have to "pick your poison", as it were.

[Paul McGaha]

Brent,

I'm not sure what the thickness of your stock is but a glue line rip blade is best used for stock 1" or less.

I run a glue line rip blade in my table saw almost all the time. I'm really happy with them.

I use a Freud ripping blade for stock larger than 1".

With troubleshooting the burning it seems to me the problem would be in either the saw, the wood or the blade. I suggest you see how it cuts on a different piece of wood. Or the same wood with a different blade. Try to get down to a common denominator.

PHM

[Stephen Cherry]

What's the other side look like?

Have you aligned the saw?

[curtis rosche]

what about trying a riving knife or splitter the same width as the blade? keeps the wood from pinching the blade and burning as much,

[glenn bradley]

I think we've hit all the bases:


Use a properly scaled splitter for your blade kerf.
Be sure your blade is clean and sharp.
Glue Line Rip blade is optimized for 1" and thinner stock and so may not be appropriate.
Burning on both sides indicates a varying feed path (or stress release) more than an alignment issue.

Freud's TK Rip blade has a .094" kerf and the Glue Line Rip has a .091" kerf. Both have a .071" plate. While the Glue Line is narrower, its not by much (.0015" per side). On the other hand, if my fence was out of parallel by .0015" from front to rear, I would say it was .0005" too much so this could be part of the issue along with other contributing factors.

[Chris Fournier]

Saw set up is critical but alder is also very prone to burning on the rip so don't feel too badly. Your set up and technique will need to be very good to avoid any burning. It can be done.

[Howard Acheson]

From the picture, it looks like you are ripping a wide board. It also looks like you are cutting a hard wood board. To have any chance of getting a good cut you must be sure your saw properly alined and that you are using a blade designed for ripping wide boards. The tooth count should be 24 or less.

[scott spencer]

If it's the 30T LM75 GLR, they're definitely more prone to burning than a 24T ripper, plus they're not intended to rip materials over 1". The same characteristics that give a highly polished edge can also increase the chance of burning. Raising the blade slightly higher can help, as can keeping the blade clean. Stock that's been jointed flat and straight is less likely to burn too. It's also worth double checking your alignment.