LumberJocks

10" Table saw blade tooth configuration

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by laketrout36 posted 09-01-2014 02:34 AM 1385 views 0 times favorited 16 replies Add to Favorites Watch
View laketrout36's profile

laketrout36

197 posts in 1494 days


09-01-2014 02:34 AM

Topic tags/keywords: table saw blade atb ft

Working on a new project and discovered that my current saw blade (ATB) style is leaving some undesireable material after the cut. The left over material resembles a small triangle, the same shape of area that the ATB doesn’t touch. I could use a chisel and clean up the left over material but I’d rather it be cut out in the first place. Could this be a result of an blade that needs to be sharpened?

Is anyone using a flat top tooth configuration or maybe a combination blade that incorporates a one flat tooth among the the Alternate Tooth Bevel teeth that would accomplish the same cut? I know each one has a specified purpose for material and either rip or crosscut.

Thanks for reading and any info.

Larry


16 replies so far

View karter56's profile

karter56

6 posts in 858 days


#1 posted 09-01-2014 12:37 PM

I recently purchased an Irwin Marples 50T combination blade for my table saw. These blades have amazing quality cuts for the price. No blowout and no left over material. I was able to cut, clamp and glue with no cleanup. I would highly recommend this blade to anyone. The Marples line is made in Italy and performs better than the Freud blade it replaced.

-- Yes, dear. Whatever you say, dear.

View knotscott's profile (online now)

knotscott

7224 posts in 2843 days


#2 posted 09-01-2014 12:58 PM

Wood will only be removed where there is material on the teeth. That triangular ridge is a product of an ATB or Hi-ATB grind. Even an ATB/R combination grind won’t have a perfectly flat bottom, but will have a less pronounced than a pure ATB grind. The only grind that will leave a perfectly flat bottom is a flat top grind (FTG). There’s never a free lunch though…an FTG blade will tend to leave more tearout on crosscuts than an ATB, Hi-ATB, or ATB/R grind, which is one of the reasons they’re primarily used as rip blades.

ATB – Alternate Top Bevel (ATB) is a very versatile grind that features a bevel across the top of the tooth that angles from the outside in, alternating between left side and right side. The angle of the top bevel can vary from about 10° to approximately 20°. The steeper the top bevel angle, the less tear out the teeth will cause, but also becomes increasing less efficient at ripping as the bevel increases. The versatility of the ATB grind makes it a very common grind on many types of blades, especially woodworking blades. The top bevel helps reduce tear out on cross grain and plywood cuts, is reasonably durable, and can still be fairly efficient at ripping with the grain. The ATB grind is very well suited in a configuration as a higher tooth count dedicated crosscut blade, and as a versatile medium tooth count general purpose blade. Note that the top beveled teeth produce a slight “V” in the kerf of the cut, so will not leave a truly flat bottom in groove cuts.

Hi-ATB – Teeth with a top bevel of roughly 25° or higher are commonly referred to as High Alternate Top Bevel grinds. Hi-ATB grinds are a variation of the ATB grind, and have the lowest tear out characteristics of any other grind. They’re extremely well suited for ultra clean cuts in plywood, laminates, melamine, veneers, and ultra fine crosscuts in hardwood, so are most commonly found in high tooth count blades intended for those purposes, but are also starting to show up in some general purpose designs. The sharp points of the higher bevels give up some durability and some ripping efficiency compared to some grinds, but can still give good edge life for low volumes (like those of a hobbyist) .

ATB/R – The ATB/R grind is a combination of two different tooth grinds in one blade. It typically features groupings of five teeth that consist of four ATB ground teeth and one flat top “raker” tooth with large gullets between the groupings. Note that the ATB ground teeth protrude slightly above the flat raker tooth, so this configuration does not leave a perfectly flat bottom….it tends to leave slight grooves along the edge of the cut similar to most stacked dado sets (a trait often called “bat ears”). Common configurations are found in a 10” blade with 50 teeth and a moderately steep hook angle of 10° to 15°. The ATB/R combination grind is well suited for both ripping and crosscuts, and general purpose woodworking applications on a table saw or compound miter saw, but use a variation with a milder hook angle suggested for SCMS and RAS.

FTG – Flat top teeth are used on blades intended primarily for ripping wood with the grain. A flat top grind (FTG) is very efficient at removing large chips from the kerf, and is a very durable grind that tends to have very good edge life. A flat top grind is the only grind that will leave a truly flat bottom kerf, which also makes it a good choice for cutting grooves and splines. The FTG is commonly found on ripping blades with a steep positive hook angle and lower tooth count, typically 10 to 30 teeth, but can also be found as part of a combination grind in a variety of hook angles intended for other applications.

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View TheWoodenOyster's profile

TheWoodenOyster

1275 posts in 1402 days


#3 posted 09-01-2014 01:13 PM

^ This guy is the table saw blade guru. Read his info and it will tell you what you need to know.

-- The Wood Is Your Oyster

View paxorion's profile

paxorion

1102 posts in 1513 days


#4 posted 09-01-2014 01:21 PM

As knotscott said, a ATB-R (most 50T combination blades) will leave small batwings from the ATB before the raker cuts a flat-ish groove. A FTG rip blade would be the answer you are looking for.

-- paxorion

View laketrout36's profile

laketrout36

197 posts in 1494 days


#5 posted 09-01-2014 02:35 PM

Very informative and helpful.

Thank you all

View laketrout36's profile

laketrout36

197 posts in 1494 days


#6 posted 09-01-2014 02:48 PM

I just looked through Irwin tools website and didn’t see and woodworking saw blades with a Flat Top grind. I’d prefer not to spend too much on this. Using a chisel to clean up the left over material might be an option.

View bigblockyeti's profile

bigblockyeti

3668 posts in 1188 days


#7 posted 09-01-2014 03:10 PM

Sometimes getting a specific grind blade can be expensive due to what manufacturers you have to choose from. Irwin is always going to be less expensive than Forrest. That being said you can get a decent 50T combination blade that would perform better for the application you’re working on for not a ton of money. If you do get a FTG ripping blade you can safely cross cut with it, but you will have tearout.

View paxorion's profile

paxorion

1102 posts in 1513 days


#8 posted 09-01-2014 09:29 PM

Tooth geometry does have an impact on cutting ability. Most saw blades have an ATB tooth configuration because it gives the blade the advantage needed to slice through the wood material.

The only FTG blades I’ve found are full kerf rip blades with 24-30teeth. If you’re only looking at thin kerf blades, I have yet to find any TK rip blades that are FTG. Depending on the depth and width of cut you are looking for, a dado stack may be more in line with what you should be using. If we look beyond the table saw, the right router bit may also be an option.

-- paxorion

View paxorion's profile

paxorion

1102 posts in 1513 days


#9 posted 09-01-2014 09:36 PM

So your post got me very curious and I decided to poke around. Freud makes the LU87R010 FTG 24T TK Rip blade. If we look beyond FTG, a TCG (triple chip grind) may leave a flat bottom. The Freud LM75R010 TCG 30T TK Rip blade may also be an option.

-- paxorion

View TheFridge's profile

TheFridge

5765 posts in 953 days


#10 posted 09-01-2014 09:56 PM

Always thought about getting a blade resharpened to flat top.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View paxorion's profile

paxorion

1102 posts in 1513 days


#11 posted 09-01-2014 10:20 PM



Always thought about getting a blade resharpened to flat top.

- TheFridge

Now there is a thought…but probably one that wouldn’t yield a good blade. Would there even be enough carbide on an ATB blade to be reground to FTG?

-- paxorion

View TheFridge's profile

TheFridge

5765 posts in 953 days


#12 posted 09-01-2014 10:32 PM

Don’t know. I just have a crapload of used carbide tipped blades that would prob work If I wanted to try it out. Remember seeing something about some 7 1/4 ftg.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View knotscott's profile (online now)

knotscott

7224 posts in 2843 days


#13 posted 09-01-2014 10:44 PM

The chamfered teeth a TCG blade protrude slightly above the raker teeth, and leave a slight trough.

Other TK FTG blades are the CMT 202.024.10, Infinity 010-124, and DW Precision Trim DW7124PT….all 24T rippers. Ryobi used to offer a 36T TK FTG blade made by Freud, but it hasn’t been made in a while. Bosch used to offer a 60T TK FTG, but am not sure if they still do.

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View laketrout36's profile

laketrout36

197 posts in 1494 days


#14 posted 09-02-2014 01:26 AM

Paxorion. I should just use the router table. Thanks for the reminder.

View buildingmonkey's profile

buildingmonkey

242 posts in 1015 days


#15 posted 09-03-2014 02:55 AM

You should have a rip blade, a crosscut blade , and a plywood blade. All marked for proper use. I ordered those 3 from Carbide Processors, .com, and got Tenryu brand, best blades of my life. Wow.

-- Jim from Kansas

showing 1 through 15 of 16 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com