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?
Most RAS's have a splitter built into the guard. Let that remind you of which direction to feed stock when ripping.
Done correctly the RAS fence keeps the board from moving backwards. If you are using a sled to push the board into the RAS the blade could aggressively grab and bad results could happen. For those that think pushing the blade is correct, the blade is always trying to lift the board. When correctly pulling, the blade is pushing the board down against the table and against the fence.
Is the above in the rip position or crosscut?
I am only using my RAS in the rip position. NO movement of the motor.
The motor is fixed!
Obviously in the crosscut position. Some folks who are used to using a SCMS think the same technique of pushing the blade through the work on a crosscut applies to a RAS. It doesn't. In the rip position on a RAS, the work should be fed against the rotation of the blade, the same as a tablesaw.
You're not getting the full utility out of your RAS. What it excels at when properly adjusted is crosscutting, particularly if you also have a tablesaw for ripping.
The splitter is on the front side of the guard when cross cutting. When ripping the splitter should be down and on the back side of the blade from the feed side. You should feed the wood against the spin direction of the blade. The splitter will then be positioned in the kerf on the back side of the blade. You cannot use the splitter in the cross cut position with a RAS. The cross cut operation is the opposite to ripping. When properly cross cutting there is not kerf for the splitter to be located in as the splitter is in front of the blade when cross cutting.
If the arm travel would be as smooth as my slide table, fine.
It isn't.
The slide table is mounted on my table saw top and BOTH are mounted on my Craftsman 10" radial saw.
I have, in effect, an upside down table saw that tilts on both directions.
Can you imagine it?
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.
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?
David Starr wrote in news:47f77250$0$11347$ snipped-for-privacy@roadrunner.com:
*snip*
At the very least, pull the yellow safety tab out of the switch before you do anything. It's easy protection. (It's still a good idea to unplug the saw, of course...)
Puckdropper
innews:47f77250$0$11347$ snipped-for-privacy@roadrunner.com:
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