On Apr 5, 7:10 am, Peter Huebner wrote:
In article ,
says...



On Apr 1, 9:22 pm, Markem wrote:
On Tue, 1 Apr 2008 17:15:57 -0700 (PDT), BoyntonStu
wrote:

How do you rip without pushing?

Tablesaw!

Mark

Thanks a lot.

What is the difference between pulling a RAS towards yourself and the
board, and keeping the RAS fixed and sliding the board on a sled away
from yourself into the blade?

Wouldn't this be opposite the instructions and warnings?

To rip with a RAS you swivel the saw around so the blade is parallel to the
fence. It's a good idea to install a featherboard that will push the timber to
be ripped against the fence. You then feed the timber into the blade, so that
the blade throws the chips into your face, rather than the blade pulling the
timber through. It's messy. It's not as accurate as ripping on a tablesaw and
nowhere near as good as ripping on a bandsaw. It also gets dangerous towards
the end of the board that you're pushing through. Pushstick is a must there,
and a receiver at the far end to hold the board is preferable. I certainly
wouldn't recommend doing production runs that way.

Having said that, I once used my RAS to rip weathergrooves into a couple
hundred meters of 3" battens for vertical board and batten cladding.
Preferably, I'll never ever do that again.

***

As for push vs pull - this is what I do: hold the wood firmly agains the fence,
with the saw behind the fence. With a straight arm, shoulder behind the arm,
pull the saw towards me, while firmly holding the wood against the fence. If
the saw wants to climb, I have the physical means to slow it, and if it gets
out of control after all, the thumb is near the power button ( I hope: at least
on my saw it is ). This can happen with very wet and or hard wood if you go too
fast in the first place. There's a learnig curve to that, it hasn't happened to
me in years and years. NB: if the saw does climb, you'll have to re-adjust or
at least check EVERYTHING afterwards.

When I was still learning the tool I tried the push technique. A couple of
times the saw grabbed an offcut and flung it - chucked an 8" length of 2x4 20
yards across a building site once, and smashed a hole into a sheet of ply on
another occasion. Nearly collected the rebound with my head. I don't know why
it happened that way, but it did. Lets just say I do not push the RAS into a
cut any more ... unless I am doing a partial depth cut only to rough out a
tenon or a lap joint, then I go back and forth, back and forth while moving the
timber from side to side into the line of cutting. It's safe for partial depth
cuts.

RAS has been the main tool in my shop for 20odd years, cause I had a crap
bandsaw. Since I've bought the new BS, the RAS is starting to lose a lot of
ground. But it's superb for cross cutting long chunks of lumber

-P.

--
=========================================
firstname dot lastname at gmail fullstop com

Ripping safety and kickback are both dependent upon the rip fence
length.


Using the full length RAS back fence is dangerous.

Why?

Once the blade is though the board that portion of the board is cut.

There is no need for a fence beyond the cut.

Anything longer than that is a part to be pushed against, the first
requirement for kickback.


What is needed is a very short rip fence, just long enough to guide
the board to a complete vertical cut.

After that point, both portions of the cut board are free to go their
own ways without any possibility of kickback.

This is why IMHO ripping on a RAS is inherently dangerous.

Do you now see the rip advantage of my upside down table saw design?