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Rank: Newbie
Groups: Member
Joined: 9/18/2010
Posts: 0
Location: Santa Cruz, CA
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I'm introducing this semester's new students to the table saw and wonder what current thinking is among teachers about what blade height should be. I have always taught students to keep the blade about 1/4" above the wood to reduce the amount of blade exposed. Others point out that having the blade higher reduces the chance of kickback by changing the direction the teeth are traveling where they are in contact with the wood.
What do all of you teach?
(Of course I also require guard, splitter/riving knife, push stick/push block, even plexiglass covers on sleds, etc.)
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Rank: Newbie
Groups: Member
Joined: 11/9/2011
Posts: 0
Location: Kansas, the land of Ahhhhs!
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I teach 1/4" also, but an easier way is I tell them to the bottom of the gullet on the teeth which is really like 5/16" on a common combo blade.
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Rank: Newbie
Groups: Member
Joined: 3/7/2008
Posts: 0
Location: North Kingstown/RI
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I agree to the bottom of the gullet as well. I like 1/8" above the work but sometimes that changes with blade dynamics.
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Rank: Newbie
Groups: Member
Joined: 6/1/2006
Posts: 0
Location: Connecticut
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I too teach "one tooth's height" which is essentially the same as the "bottom of the gullet". I believe that this is the generally accepted way to go. Admittedly with a SawStop this becomes a less critical issue, but I believe that the logic is that the less blade you have exposed above the work surface, the less severe will be the resulting bite. Also, I disagree with the idea that a low blade increases the likelihood of kickback. Kickback occurs when the back of the blade (the part where the teeth are rising up out of the table) lifts the board up off of the table, thus bringing the underside of the board into contact with the forward spinning top of the blade.
Keith Landin
Woodshop instructor, Woodstock Academy
"Mens tua sit implementum acerrium in fabrica"
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Rank: Newbie
Groups: Member
Joined: 4/16/2006
Posts: 0
Location: Bend, Oregon
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A rep from Freud saw company told me that the blade will do a better job cutting if it is raised to the gullets. This allow the sawdust to escaped better and allows for better cooling of the blade while cutting. For what it is worth
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Rank: Newbie
Groups: Member
Joined: 1/16/2008
Posts: 0
Location: Georgetown/OH
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the thickness of the carbide.
a low blade runs cool because it pulls air in and allows the gullets to act as an air pump. It also discharges the dust out of the bottom. If you raise the blade to where the surface below the teeth is into the material then you increase the friction and also increase the heat build up. THis can cause kickback. If you have ever run a sawmill you will alos know that this (heat) can cause the blade to deform.
Another way to look at it is that after kickback the most common way to get cut on atablesaw is to run your finger across the blade on top of the material. If you have the blade set at 1/8" this is a pretty bad cut, but if it is at 5/16 or 1/2 then you have a missing finger.
I would seriously question the rep that suggested exposing the gullets. On some baldes they may be close to the depth of the carbide, but on most combo blades the gullet is almost 5/8" deep.
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