Ripping 12 foot PT TwoBy

On 4/15/2011 8:02 AM, Hoosierpopi wrote: ...

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By model number for a hand circular saw; no...

Any of the rip blades other than, perhaps, some off-the-wall $2 throwaway will be fine. Which, specifically, you choose will depend at least a little on whether you're just ripping for construction purposes or whether you're trying to get a finish edge.

For former, go w/ fewer teeth; for the latter, better finish at cost of slower work but for only a couple, who cares? (Altho I'd tend to think you'll get better overall longterm use of the rough-cut blade that would be a better value, but that's a guess not having any idea of what your typical work would be...)

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I'd go for something teflon coated.

-Brian

The guys who framed and did some of the exterior trim on our house used the cheapo Irwin carbide multipurpose. They were about $6 each and they "used them until they wouldn't cut butter" and replaced them. None of the work was PT, but they cut lots of 2 x 4 up to

RonB

Probably more important than the blade will be using a wedge behind the blade to keep the board from pinching and binding the blade. A rip blade will cut easier, but keeping a wedge behind the saw will make the job go much faster with whatever blade you use.

I have also had good luck with a cheap Irwin carbide blade for utility cutting.

Jon

Go look at the blades, look for low tooth count, positive hook angle, thin kerf.

A rip blade will be about 20degrees positive hook and have a dozen or fewer teeth, thin kerf means less power required because you are removing less wood as sawdust. Drop a fat screwdriver into the cut or some other wedge to hold the kerf open as you progress down the board.

...this from an olde track framer in SoCal. Your boards are only 12' in length; I'd use any carbide blade with 24 teeth (the old B&D Piranha comes to mind)...you have a Skil-Saw so just jam through 'em. I wouldn't think to use any kind of wedges or screwdrivers 'cause I'll be through that cut pretty dang fast, and the blade is small and I'm workin' with a lot of power. I'm not a big fan of thin kerf for this kind of work, a good ol' 1/8 kerf *thick* blade takes advantage of the power of the saw and puts it to good use plowing through the cut without a bunch of drifting. Just my .02, but this kind of stuff is full autopilot for a framer.

cg

I try to stick with the 16 or 18-tooth Piranhas for ripping.

Agreed, the stiffer blades work better for freehand rips.

-- If only he'd wash his neck, I'd wring it. -- John Sparrow

...yup...a few less teeth will do better...I got a whole wheel of steel blades that would work great, too, but I keep forgetting I got 'em!

cg

"Charlie Groh" wrote

...this from an olde track framer in SoCal. Your boards are only 12' in length; I'd use any carbide blade with 24 teeth (the old B&D Piranha comes to mind)...

I agree about plowing though the rips. The saw brand makes a difference. A Milwaukee has more gear reduction and therefore more torque than any standard design saw that I am aware of. A Makita spins fast with no torque. Of course, a worm drive saw of about any brand beats all for torque on demand.

-- Jim in NC

Thank you all for the input. Will use the wedge. Went to LOWES today and could not find a single .25" blade labeled "Ripping." I did find one labeled Framing/Ripping so I guess, based upon what I read here, I'll go with one of those.

Flat Top (FT) Flat top teeth are used on blades made for ripping hard and soft woods. Since wood is much less likely to chip and splinter when it is being cut in the direction of the grain, the focus of a rip blade is to quickly and efficiently remove material. The flat top tooth is the most efficient design for cutting and raking material out of the cut.

A blade for ripping lumber on a table saw will generally have a high hook angle, where an aggressive, fast cut is usually what you want. Radial arms saws and sliding compound miter saws, on the other hand, require a blade with a very low or negative hook angle, to inhibit overly fast feed rate, binding, and the blade's tendency to try to "climb" the material.

In general, blades with more teeth yield a smoother cut, and blades with fewer teeth move material faster. A 10' blade designed for ripping lumber, for example, usually has as few as 24 teeth, and is designed quickly move material along the length of the grain. A rip blade isn't designed to yield a mirror-smooth cut, but a good rip blade will move through hardwood with little effort and leave a clean cut with a minimum of scoring.

Rip blades have a fewer number of teeth than crosscut or combination blades, typically twenty to twenty-four on a ten inch blade. The low tooth count combined with large gullets and an 18 to 20 degree hook angle makes Amana rip blades fast and aggressive.

Does anyone even bother to cite their source for cut-n-paste, anymore?

Some still do, though it has become noticeably less common.

My first preference would be to rip with a bandsaw, actually; less kerf, less sawdust. But, feeding something that long to a stationary tool is a two-man job.

I've not seen rip blades in throwaway carbide for 7" skilsaws, but if there are any, that'd be a good choice. Remember to collect and dispose of the sawdust, it has toxic stuff in it. Give the poor saw a few minutes to cool between planks.

FWIW, I went to the B&D site and found that instead of just having the Piranha blade, all their blades are "Piranha" from the cheapest all steel to the most deluxe carbide, and they don't seem to be making the one that they used to sell as the "Piranha" anymore.

Maybe the Chinese factory burned down and they lost the tooling or something.