Help! Miter Saw burning through 2x4s

[Woodnut]

I have an OLD 8" Delta compound mitersaw. in the last 3 months it started not so much cutting my 2x4s as burning thorugh them. I thought it was my blade (which was the origininal) and after removing it, felt confident I was right (some of the teeth were rounded.)
So I just got a Dewalt 40T 8.25" finishing blade and installed it. Got a piece of scrap and expected a hot-knife-thru-buttah experience.

Nope.

Smoke in the overhead, and dark burn marks on the 2x4 scrap.

Any ideas guys?

[cabinetman]

I have an OLD 8" Delta compound mitersaw. in the last 3 months it started not so much cutting my 2x4s as burning thorugh them. I thought it was my blade (which was the origininal) and after removing it, felt confident I was right (some of the teeth were rounded.)
So I just got a Dewalt 40T 8.25" finishing blade and installed it. Got a piece of scrap and expected a hot-knife-thru-buttah experience.

Nope.

Smoke in the overhead, and dark burn marks on the 2x4 scrap.

Any ideas guys?

What model Delta saw do you have? You might try a carbide tipped blade with less teeth.

.

[Daryl]

Is the blade on correctly? Don't blush, it happens.

[LCHIEN]

Is the blade on correctly? Don't blush, it happens.

yeah, my first guess would be that the blade is on backwards.
viewed from the left hand side you should be able to read the label (at least most of the blades I've seen - Pelligrini indicates some are not).
the top of the blade rotates forward, the cutting edge of the teeth should hit the wood first.
Viewed from the left side, the blade rotates clockwise, there's usually also some arrow on the blade showing direction of rotation.

[pelligrini]

viewed from the left hand side you should be able to read the label.

Not all blades are like that, but most are. My Olshun 24T ripper has the printing on the other side. I've put it on my tablesaw backwards a couple times because of the label being on the right side.

[sweensdv]

Look at the blade as it comes to a stop. If there is a wobble in the blade you may have a bent arbor or possibly a bearing problem.

[cwsmith]

A 40-tooth blade should work just fine. (I use a 50-tooth on my Ridgid 10" CMS.)

I have to admit that I am a bit surprised that you would use the original blade so long and to the point where some of the teeth are actually "rounded" as you mention. To that, I am wondering if you have had to really force that old blade to the point where you could have damaged the arbor. I would be surprised as I can't really imagine such force would actually cause such damage though.

How does the kerf look, are there burn marks on both sides, or just on the trailing or leading edges of the blade cut? Also, many people make the cut and then lift the blade while the saw is still running... if you do that, try making the cut and then turning it off, let the blade stop and then lift it and see where the burn marks are (that's the "suggested" way to use a CMS anyway).

Wobble is fairly easy to detect and is often quite noticeable immediately. "Heel" however, is not as easily noticed and that may well be a problem with the burning. I had that problem when I re-setup my RAS after years of storage. That cause some very noticeable burning and a significantly lousey kerf.

I'm not sure how that is adjusted on the CMS as I've yet had to do that and don't have the manual readily at hand, but I suspect it to be an issue here.

Finally, I should mention the speed of your cut or feed of the blade into the wood. I don't know what there is about the CMS but I've seen so many of the contractors that I've watched just grab that handle and almost "drive it" through the stock. Not inferring that you particularly would be doing that (no offense meant), but thought it worth mentioning. Like with any saw, the blade needs a chance to "work" it's cut and too much speed will burn or worse.

Let us hope that your problem can be "adjusted" to perfection; and that you don't have damage.

Good luck,

CWS

[gerti]

Viewed from the left side, the blade rotates counterclockwise

Erm... clockwise, right?

[LCHIEN]

Erm... clockwise, right?

yes, you're right, had a brain fart, was thinking clockwise and typed counter CW. Fixed it.

[Woodnut]

I'll check

Thanks for the advice guys. I'll check the rotation (again) but I'm pretty sure I had it right.

(Been married for 28 yrs, so have learned how to be wrong...)

I'll look at the cut and see if I'm wobbling or cutting straight-at-a-slant.

After this many years, I don't need that much prompting to get a new saw. Just don't like to spend money I don't need to...

[LCHIEN]

not that you need any motivation but an 8" mitersaw must have a very small capacity... barely able to cut a 2.5" thickness wise and barely able to cut a x4 width wise. Probably at 3.5" wide and 45 degrees it'll just make a miter cut?

[cabinetman]

I've never cut with a backward blade, as that could play havoc with the teeth, and I would think you'd get more than just a little burn mark on the edge. More than likely, dull/gummy/too many teeth account for the problem.

Some spcs for an 8.25" saw:
1 HP motor, 110V / 60 Hz
Cross cuts up to 2" H or 4-3/4" W at 90 Deg.
Miter up to 2" H or 3-3/8" W at 45 Deg.
Bevels up to 1-3/8" H or 4-3/4" W

For an 8.5" saw:
1-horsepower motor
Cross cuts up to 2 inches high to 4.75 inches wide at a 90-degree angle
Miter cut up to 2 inches high to 3.75 inches wide at a 45-degree angle
Bevels up to 1.375 inches high or 4.75 inches wide

.