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Jan Bianchi
12-15-2007, 12:22 PM
I was reading last night about sawing one inch strips on a table saw. Someone advised raising the blade to its full height, even though I'm only working with a one inch thickness. They said it would ensure a squarer cut (which is what I want). Is that right? If so, why do they normally tell you to raise the blade only 1/4 above the surface.

glenn bradley
12-15-2007, 12:26 PM
A higher blade has a more exaggerated down angle at the leading edge. With the proper blade for the job, I've never seen an improvement in cut with a high blade position. If your blade is square to the table the height should not change that relationship so I don't believe the recommendation was targeting a more accurate cut, maybe a better quality edge. I just clear (or nearly clear) the tooth, as a rule.

Full height could be particularly dangerous with narrow strips. Have you made a jig so your 'keeper' ends up on the 'waste' side of the blade or do your have Grr-Rippers or a shop-made push block is the 'keeper' will ride the fence? Your fingers don't belong close enough to the blade to do 1" strips. Push sticks, push sticks, push sticks.

Jan Bianchi
12-15-2007, 12:38 PM
Yes, I do use a pusher on the fence side, which is why I wasn't overly excited with the idea of a high blade. I don't have one for having the keeper on the waste side. I have to cut several strips. Is one better than the other?

Thanks for the advice on blade height. It seemed odd.

Rick Christopherson
12-15-2007, 1:14 PM
I recommend using a higher blade height than 1/4 inch, and have an article explaining the reasons: See Tablesaw Safety (http://www.waterfront-woods.com/Articles/Tablesaw/tablesaw.htm)

However, I do not recommend raising the blade to full height, and especially not for making narrow rips. The reasons for raising the blade is to reduce drag and decrease the chances for a kickback, but not because it will give you a better cut. Also, as Glenn stated, this will not change whether or not the cut is square.

Cliff Rohrabacher
12-15-2007, 1:49 PM
Blade all the way up~??
Yah it might make for a more square cut if the operator isn't able to get the blade set square in the first place.

It would also reduce a particular form of kick back that results from the stock creeping up the blade, getting snagged and slammed back and down. Hurts the pinkies something fierce when feeding directly by hand.

I Wouldn't do it though. All that whizzing metal would make me nervous.


Just take more care to get the blade square.

Jim Kountz
12-15-2007, 2:33 PM
I raise the blade enough for an entire tooth to clear the top of the workpiece.

Andrew Nemeth
12-15-2007, 6:52 PM
I believe the reason to set the blade high is to produce a smother cut, not a squarer cut. Although I have never actually found that it has made a noticeable difference in my work.

I usually set my blade just high enough for the tooth to clear the top of the board I am cutting. I know it increases the chance for kickback (as stated in the article above) but that is only half the story. It also reduces the amount of damage you can do to your finger or hand if you happen to touch the blade. If it was not for this advise I would have surely lost a thumb. I was pushing a narrower board through the TS when I was distracted with other thoughts and let my thumb pass over the blade. Instead of loosing a thumb, I walked away with a 3/16" x 3/16" grove in the fleshy part of my thumb.

I try to keep my hands in front of the blade as much as possible to prevent them from being drawn back into the blade if there is kickback. I also use fingerboards to keep the board held down and square against the fence if I am at all apprehensive about how close my fingers are to the blade throughout the cut. I am also in the habit of wrapping my fingers over the top of the fence and only pushing with my thumb as this gives my hand some stability and also keeps it help in place if the board does try to kick back.

So, if your interested in cutting a lot of narrow rips from a wider board one of the safer ways to do it is to clamp a short block (jig) near the front edge of the saw, on the "waste" side, that is offset from the blade at whatever distance you want your pieces to be ripped at. The block should not even come close to being perpendicular to the blade as this could trap the piece being cut and cause kickback. For each cut you will need to push your stock up against the block and then push your fence up against that and lock it down. Your keeper piece will actually be coming off the "waste" side of the blade. This method will only work if both edges of the board you are ripping are parallel.

I hope this description is understandable, if you have any questions about the method please ask.

-Andrew

Rob Blaustein
12-15-2007, 9:42 PM
Rick's argument is an interesting one, and although off topic a bit applies to the blade depth setting using a circular saw. In fact it was Rick who suggested this to me in a different forum when I noted that my saw bogged down cutting thick pieces--setting the blade to full depth bogged the saw down less.

David Epperson
12-15-2007, 10:37 PM
Rick's argument is an interesting one, and although off topic a bit applies to the blade depth setting using a circular saw. In fact it was Rick who suggested this to me in a different forum when I noted that my saw bogged down cutting thick pieces--setting the blade to full depth bogged the saw down less.
Makes sense since there would be fewer teeth in the cut at any given time.

Bruce Wrenn
12-15-2007, 10:42 PM
You want between three and five teeth in stock at all times for best cutting.

Jim Becker
12-15-2007, 10:46 PM
Kinda a compromise all around...lower is perceived as safer, but too low and lifting of the workpiece becomes more likely. Too high brings the blade into much closer proximity to the hand than I personally would be comfortable with. I generally cut with the blade gullets clearing the work piece for a couple of teeth, but will vary it depending on the cut and my comfort level. For narrow strips, I tend to keep it lower so I'm not sacrificing too much of my push BLOCK (NOT a push "stick" which I'll never ever use) with each pass over the blade. And a splitter or riving knife is not optional, IMHO.

Robert Mahon
12-16-2007, 8:49 AM
The only time I have the blade raised to it's full height is when I am cutting a piece away from a larger piece so there's less loss at the intersection of the cuts. I do this in order to preserve the lengths of a board (or plywood) rather than be left with a bunch of shorter pieces (have I written this so it can be understood?).

Rob Blaustein
12-16-2007, 9:32 AM
The only time I have the blade raised to it's full height is when I am cutting a piece away from a larger piece so there's less loss at the intersection of the cuts. I do this in order to preserve the lengths of a board (or plywood) rather than be left with a bunch of shorter pieces (have I written this so it can be understood?).

Not sure I follow--are you saying the kerf is narrower with the blade set higher?

David Epperson
12-16-2007, 10:43 AM
Not sure I follow--are you saying the kerf is narrower with the blade set higher?
not narrower, just that the excess undercut at the end is shorter.

Jake Helmboldt
12-16-2007, 10:55 AM
Higher blade does help reduce splintery tearout on woods prone to that. I was (cross)cutting ipe yesterday and had to raise the blade to avoid such since ipe has a lot of fine splinters.

Nissim Avrahami
12-16-2007, 1:53 PM
In one of books about table saw the author is saying:

"When the blade is high, the cut is at its cleanest and most efficient"

I visited one of the shops (well, looks more like a factory) that they are cutting plywood, melamine and MDF sheets with 3 big sliders and they are running with the blade at full height.

When I asked why, he told me..."we are cutting here non-stop...if the blade is low the feed is slower and the blade may overheat and can deform but, when we are cutting 1/4" or thinner material, we use low blade because the material tend to vibrate up-down after it passes the blade"

I'm setting very high blade but I also use the guard and other devices to keep my hands far away from the blade...

I noticed that when I'm cutting 1¼" white Oak, the feed is easier and faster when the blade is at full height...but, I'm not an expert, just my impression...

niki
77242

Robert Mahon
12-17-2007, 7:16 AM
Fact is; the higher the blade is raised, the less of it is actually in the wood. Benefits of this are (1) less chance of a kickback because the blade pushes more down than back to you, (2) Less heat is generated, (3) cleaner cuts when cutting things like Plywood, MDF and Melamine surfaced materials, (4) shorter kerf/less waste on the underside of a piece when cutting a smaller piece from it.
I'm confident there are probably more benefits but that 3 HP Veg-o-matic spinning at 4,000 RPM scares the beJesus outa me and I like to have it nicely tucked away when I'm near it. In truth, I never have the blade exposed when the saw is not being used.

It's not being paranoid. That thing really is out to get us.;)

Charles McCracken
12-17-2007, 8:22 AM
Jan,

For Freud blades we recommend 1/2 of a carbide tip above the material being cut. If you are using the correct blade for the application this will yield the best results. As Bruce Wrenn noted, 3 to 5 teeth working in the wood is the ideal when ripping (5 to 7 for crosscuts and sheet goods).

Anthony Anderson
12-17-2007, 9:41 AM
I generally cut with the blade gullets clearing the work piece for a couple of teeth, but will vary it depending on the cut and my comfort level.

Jim, I use the exact same method of a gullet or two clearing the top of the workpiece. I was at a Freud tool demo at our local tool store recently, and the Freud truck/demo guy smirked and told me I was wrong to use this method, and went on to tell me that the "correct" method was the "teeth of the saw blade just clearing the workpiece". He gave a free blade to some guy standing next to me who came up with the Freud rep's "correct" answer:confused::rolleyes:. I don't like the Freud rep's "correct" method, as I have had the workpiece want to lift when the blade teeth were barely clearing the workpiece. The Freud rep went on to trash everything that is made in China, stating how the Forrest Woodworker blades are inferior blades, and extolling the virtue and ethics of the Freud plant and their products:rolleyes:. As I was leaving, the Freud rep asked me if I learned anything. "Oh yeah!;)", I said. He offered me a 7.25" construction blade. I told him he could keep his free blade.

I have A LOT of Freud blades and bits, and still love them. Not saying that the Freud guy's method is wrong, but I wouldn't use it, and it does not work for me, nor does it make me feel safe. And I have to feel safe when using my tools. The Freud Truck/rep thinks he knows more than he really does, and not just about tools. He really rubbed me the wrong way.

Okay, sorry for straying a little off the topic. It won't happen again. But anyway, I allow a couple of gullets to clear the top of the workpiece. It has, and continues to, work well for me. There, now back on topic. Bill

Frank Orzehoski
12-30-2007, 4:50 PM
I raise the blade enough for an entire tooth to clear the top of the workpiece.


That is what I do as well. Works well for me.

John Thompson
12-30-2007, 7:11 PM
I have met Charles at IWF and he knows his stuff... but this is one point I have to agree with Rick on. I raise the blade so the gullet at center-line of saw blade is just above the wood. Similar to what Jim B. and Anthony mentioned they do.

Too low... no go! Too high... don't even try!

Sarge..