RAS vs Mitersaw

[Ruhi Arslan]

I came across quite a few references to "dangers" of RAS. I did a quick search and found this (http://www.sawmillcreek.org/showthread.php?120386-Why-is-a-RAS-dangerous) thread. Not quite sure if I understood why the rip cut would be more accident prone. Rotating the blade parallel to the fence seems like "safe" to do so. Also, why RAS is any different than a miter saw in terms of potential dangers - operator related or not. They both have blades rotating in the same direction, they both slide. Miter has one extra axis to worry about (up/down). I don't get it...

[Mike Schuch]

The problem with ripping on a RAS (I have ripped thousands of feet of boards on a RAS as my fathers Delta Turret arm was the only stationary saw we had when growing up) is that the revolution of the blade will lift the work piece if it catches at the cut. A table saw will pull the work piece down to the table. There is also much more saw blade exposed during ripping. We always had a 8 foot table which provided a lot of support for the work piece and helped a lot with safety. Small tables on a RAS for ripping are dangerous if the work is not supported well.

If I could only own one saw it would be a RAS. My Redstar 16" RAS is the center of my shop and where the majority of work is performed. I do really appreciate having my PM 65 and 71 for ripping boards but that is pretty much the only thing they do.

I keep a 10" miter saw on a stand at the house for convenience but use the Redstar RAS exclusively in the shop.

I believe the biggest danger of a RAS is familiarity. If you are trained to use one properly and are comfortable with it's capabilities and know how to set it up properly a RAS is as safe as any other machine that twirls razor sharp steel at high speed. I think that people who learned wood working in a table saw centric shop have the most problems adapting to a RAS.

http://www.hitechengineering.net/DNN/Portals/0/MyShop/PICT8053.gif

[Chip Lindley]

I came across quite a few references to "dangers" of RAS. I did a quick search and found this (http://www.sawmillcreek.org/showthread.php?120386-Why-is-a-RAS-dangerous) thread.




...I believe the biggest danger of a RAS is familiarity. If you are trained to use one properly and are comfortable with it's capabilities and know how to set it up properly a RAS is as safe as any other machine that twirls razor sharp steel at high speed. I think that people who learned wood working in a table saw centric shop have the most problems adapting to a RAS...


Exactly what Mike said! There's an old saying,"Familiarity breeds contempt." But, I say it is just the opposite with woodworking machinery. The more time a user spends on one particular machine, the more apt he is to master it successfully (and safely)

Not mentioned is the main difference between the SCMS and RAS. Sliders cut on the push stroke; radial-arms usually on the pull stroke. There are inherent problems with each, in that stock may lift on the slider if not firmly held down. The blade may self-feed on a RAS if not controlled sufficiently. Experience is the best teacher. After a few dozen dozen repetitive cuts on either machine, you will get the hang of it.

As to ripping on the RAS, it is not my first choice, but will certainly perform that function. Ripping is best done with the blade guard tilted down toward the infeed side to just clear the board. It serves as a hold down. One still has to deal with the deluge of sawdust thrown out by the blade. It can get really nasty!

[Neil Brooks]

They said it perfectly.

Another analogy.

If you're used to riding a motor scooter, but then you find a great deal on a used, 750 pound, Honda Gold Wing ... most of what you already know will help you transition from the toy TO the big bike.

But ... caution will be the key ... as you learn the differences, how the big boy handles, what its limitations are, etc., etc., etc.

Same idea with transitioning from a road motorcycle to a dirt motorcycle.

Other than the pure Neanderthals ... most of us do pretty well, most of the time, ALREADY working with potentially dangerous -- if not lethal -- machinery.

The RAS isn't any different.

Mine's (https://picasaweb.google.com/neil0502/1956_DeWalt_MBF_Radial_Arm_Saw?feat=directlink) been (fixed) up and running for a few weeks, now. I'm taking my time, learning my way around it, building some jigs for it, and ... gradually getting comfortable with ALL of its basic cuts.

And ... oddly enough ... I have no FEAR OF it -- just RESPECT FOR it :)

Annnnnnnd, uh ..... Chip ??? You scored. She's an absolute BEAUTY of a saw !!!

[Chuck Walker]

I use a RAS regularly for cross cutting and occasionally for ripping. It pays to learn the peculiarities of any tool in the shop especially the RAS. One mistake beginners make in ripping is to feed in the same direction that the rim of the saw is turning. The blade can grab it and turn your board into an instant javelin. Feed the opposite way and I always install my Rip-Strate to hold the wood securely and keep nudging it toward the fence. Yes, it is a nuisance to set up but my table saw is usually two layers deep in stuff and the added safety is worth it. The sawdust problem is real and capturing it is difficult in the extreme!

I frequently reach for a hand rip saw if there is not too much wood to rip. Easiest way out and good upper body exercise!

Chuck

[Don Jarvie]

One of the things I have learned with using a RAS is to hold the piece tight against the fence. As discussed you pull the blade during a cross cut and the blade is traveling with you as you pull. If the wood isn't tight against the fence the wodd comes along and the blade binds.

Once you learn the nuiances of the RAS it's a great tool.

[Bruce Wrenn]

Most RAS accidents are caused by a loose nut. The one operating it. Anything that has teeth eats meat. Saw blades have teeth.

[David Winer]

I came across quite a few references to "dangers" of RAS. ...
Adding to the good advice from the above posts:

For three decades before getting a table saw I ripped happily with a RAS, never a problem. Note, however, I meticulously set the guard almost in contact with the board, and adjusted the splitter and antikickback fingers exactly per the saw’s manual.

I never knew about low or negative hook angle blades as currently recommended. Cross cutting with positive hook blades was not a problem since I quickly got the feel of controlling the cut with a pushing back pressure, using locked elbow/forearm/wrist while pulling through mostly using shoulder and torso. Always keep a cross cut board pressed against the fence.

A recent thread here on SMC discussed RAS miter cuts to the left as being problematical. Just remember not ever to do a cross cut operation with a forearm in the blade’s path. In other words, if you can’t pull with right arm and press the board with the left hand, then pull with the left arm and press the board with the right hand.

[Larry Edgerton]

Everyone I know with missing fingers from a RAS was ripping. Seems that ripping is the problem to me. I don't rip with mine, no problems. I look at it and I don't even see a machine that was really made for the job, that would be a tablesaw.

I like my OMGA, but if I could only have one tool, that would not be it.