Dado cuts on a RAS?

[tedkitch]

Does anyone do dados on a RAS? Someone at work was telling me that he does his dados on a RAS. Wouldn't there be a problem with the saw pulling your hands towards the blade?

I've been sitting here playing with my RAS and wondering how you would do it with something long. I guess you could turn the blade parallel to the fence and run board through it that way, but it doesn't look very safe to me.

Any thoughts?

[LCHIEN]

i think they meant doing cross-cut dados.
Its very good at that... you can see the dado as its being cut.

I would not do "rip-type" dados with a RAS, although I guess you could, for the reason you mention..

[Uncle Cracker]

Cross dados are easy... You are pulling the saw through the work, and it will try to "walk" toward you, but you can control the feed. Rips are more dangerous, as you are feeding the work, rather than moving the saw, and the blades will throw the workpiece if you give them half a chance. DAMHIKT

[jgrobler]

I agree with Loring, great for doing croscut dados. I don't see how the saw will pull your hand towards the blade. The workpiece is supported by the fence, the blade will push the piece against the fence, your one hand can support the piece (far enough from the blade, and not in line with the blade's travel) while the other hand is pulling the motor. If it's a small workpiece, secure it with clamps to the fence, some tables has little imbedded nuts for holding screw attachments to keep workpieces secure.

I also won't do grooves parallel to the fence.

[cabinetman]

I agree with Loring, great for doing croscut dados. I don't see how the saw will pull your hand towards the blade. The workpiece is supported by the fence, the blade will push the piece against the fence, your one hand can support the piece (far enough from the blade, and not in line with the blade's travel) while the other hand is pulling the motor. If it's a small workpiece, secure it with clamps to the fence, some tables has little imbedded nuts for holding screw attachments to keep workpieces secure.

I also won't do grooves parallel to the fence.

You are exactly right. Crosscut dadoes will have a tendency to "climb" towards you. The best bet is to take shallow cuts and slow down the pull speed, and learn to control the saw.

For ripping, a very dangerous procedure. One hand and arm has to "backside" the cut in order to pass all the way through the cut. You're pushing the stock close to the fence, and have to pull it out when it gets to the end of the cut.

Even doing long dadoes on the TS, you have to change hands or take a step or two to run a long board, while holding the sucker down tight. Very easy to get a slight drift or an uneven bottom to the dado on the TS. I prefer to do dadoes with a router. For crosscut dadoes, I use a jig I made which simplifies the process. See it here.

[cwsmith]

From many years of experience with the RAS, I would have to agree that for crosscut dado's, it's really hard to beat the RAS. But, I would never attempt to do a "rip" dado on the saw.

Regarding the "climb" factor, during crosscuts. There seems to be some challenge regarding how fast one needs to "pull" the saw into the wood. While almost everyone has some idea that you simply don't shove a board into the table saw; when it comes to using the RAS, it appears that many folks get the impression of "danger" because the saw will climb if you overfeed. Simple fact is that on crosscuts, your "pull" should be a "controlled cut", just as it would be on a table saw.

So, if you're using a dado set, your feed rate would be less than a single saw blade. The advantage of the RAS, is that with the cut exposed to view, you can see exactly what the blade is doing and control the cut. Also, please note that at no time should your hands and fingers ever be in the blade path... I'm sure you wouldn't place your hands in line with the blade on a table saw, so why should the question be raised when using the RAS?

CWS

[ragswl4]

From many years of experience with the RAS, I would have to agree that for crosscut dado's, it's really hard to beat the RAS. But, I would never attempt to do a "rip" dado on the saw.

Regarding the "climb" factor, during crosscuts. There seems to be some challenge regarding how fast one needs to "pull" the saw into the wood. While almost everyone has some idea that you simply don't shove a board into the table saw; when it comes to using the RAS, it appears that many folks get the impression of "danger" because the saw will climb if you overfeed. Simple fact is that on crosscuts, your "pull" should be a "controlled cut", just as it would be on a table saw.

So, if you're using a dado set, your feed rate would be less than a single saw blade. The advantage of the RAS, is that with the cut exposed to view, you can see exactly what the blade is doing and control the cut. Also, please note that at no time should your hands and fingers ever be in the blade path... I'm sure you wouldn't place your hands in line with the blade on a table saw, so why should the question be raised when using the RAS?

CWS

Excellent explanation and advice. When you think about it, its really common sense. Having acquired a RAS only a few months ago, I have read the book and one other about using a RAS. Both from owwm.org. Very good reads and a must read for anyone thinking of getting a RAS. Its not your typical saw. It was the one saw my father used the most during his lifetime. He loved them, but never ripped anything on the RAS. Thats why we have table saws.

[JimD]

I do cross-cut dados with my Ryobi RAS sometimes. I use the inexpensive Freud Pro stacked set which has a negative hook angle. That helps it not pull itself into the cut. My Ryobi does not have either a long arbor or a lot of power so I limit it to 1/2 inch dado.

Jim

[scorrpio]

I do all crosscutting on a RAS, including dadoes. It is excellent for that. But I never rip on it. For grooves, I use either TS or router.

[Thom2]

I got into a lengthy discussion with my Dad about saw blades for the RAS. When he started talking about rip operations, I was extremely glad for this conversation as I found out that I could very well have saved him some fingers.

Judging from the replies here, I think this is 'assumed' to be 'general knowledge', but I'm going to point it out anyway. As evidenced by discussion with my father, it's not as 'general' as I had thought.

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Ripping operations on a RAS are ENTIRELY different than crosscutting. When you move the RAS carriage into the rip mode, you will actually be feeding stock into what is normally the 'back' of the blade. The teeth off the blade are actually coming up and at you when ripping, trying to shove back at you. It is IMPORTANT to have ALL hold downs and safety guards in place if you are going to attempt this.

Feeding into the wrong side of the blade can prove catastrophic as the teeth are actually pulling the wood away from you, human reflex rates aren't all that fast and you very well could have your hands dragged into the blade before you ever thought to let go. At the very least you'll end up with a hole in the garage door/wall/window, whatever is on the other side of the blade.

To further complicate matters, there's 2 different ripping operations on a RAS, you have "in-rip" and "out-rip", each of which require using the opposite side of the table as infeed because you're turning the carriage 180 degrees.

I personally don't rip on my RAS, I just don't like it. If you are going to consider it tho', I highly recommend you have a thorough understanding of the operation before attempting it.

[LinuxRandal]

I got into a lengthy discussion with my Dad about saw blades for the RAS. When he started talking about rip operations, I was extremely glad for this conversation as I found out that I could very well have saved him some fingers.

Judging from the replies here, I think this is 'assumed' to be 'general knowledge', but I'm going to point it out anyway. As evidenced by discussion with my father, it's not as 'general' as I had thought.

-------------------------------------

Ripping operations on a RAS are ENTIRELY different than crosscutting. When you move the RAS carriage into the rip mode, you will actually be feeding stock into what is normally the 'back' of the blade. The teeth off the blade are actually coming up and at you when ripping, trying to shove back at you. It is IMPORTANT to have ALL hold downs and safety guards in place if you are going to attempt this.

Feeding into the wrong side of the blade can prove catastrophic as the teeth are actually pulling the wood away from you, human reflex rates aren't all that fast and you very well could have your hands dragged into the blade before you ever thought to let go. At the very least you'll end up with a hole in the garage door/wall/window, whatever is on the other side of the blade.

To further complicate matters, there's 2 different ripping operations on a RAS, you have "in-rip" and "out-rip", each of which require using the opposite side of the table as infeed because you're turning the carriage 180 degrees.

I personally don't rip on my RAS, I just don't like it. If you are going to consider it tho', I highly recommend you have a thorough understanding of the operation before attempting it.

Quoting the whole thing because it should be read. There is a REASON those antikickback pawls are with the RAS. Don't remove them, just slide them higher out of the way if your not going to use them. Whoever ends up with your saw in the future MAY want them! Like a tablesaw, the pawls are at the backside of the blade when in use.

And learn to use a pusher.

[scorrpio]

The Craftsman RAS I have has the new modified guard - most of its modifications are for the ripping. The guard is shaped in a way that trying to feed stock from wrong side of blade will be blocked by the guard. The guard is also fitted with a riving knife and pawls. There is also a front guard that is lowered to match stock thickness. The board will go under the guard, but the fingers on top of the board will be stopped. Even with all that safety added, I just don't feel right doing rips on a RAS.

TS is far better for the task.

[LinuxRandal]

The Craftsman RAS I have has the new modified guard - most of its modifications are for the ripping. The guard is shaped in a way that trying to feed stock from wrong side of blade will be blocked by the guard. The guard is also fitted with a riving knife and pawls. There is also a front guard that is lowered to match stock thickness. The board will go under the guard, but the fingers on top of the board will be stopped. Even with all that safety added, I just don't feel right doing rips on a RAS.

TS is far better for the task.

Supposed to drop down the back (now front in rip mode) of the gaurds with at least the old DeWalts (what I have). I thought they were all that way. (Just because I have the RAS, doesn't mean I am gonna rip on it, but also doesn't mean I shouldn't learn the proper way).

[LarryG]

Feeding into the wrong side of the blade can prove catastrophic as the teeth are actually pulling the wood away from you, human reflex rates aren't all that fast and you very well could have your hands dragged into the blade before you ever thought to let go.

So is this why radial arm saws have such a bad reputation as ripping machines -- because people are feeding the stock backwards, i.e. with the same relationship to the blade as when crosscutting?

If so, that explains a lot. My dad's shop featured an RAS rather than a TS; it's what I "learned on." Over the long years we ripped thousands of linear feet of stock, never with an incident, and because of that I have never understood all the safety hysteria about this tool. Used properly, it's as safe as any machine in the workshop.

[cwsmith]

Larry,

I agree with you, I have also ripped lots of stock on the RAS, but I've never tried to use a dado blade in the manner.

Your comment about the "same relationship with the blade" I believe is different though. On a crosscut, you pull the blade into the stock and on a rip, you feed the stock into the back of the blade... with the pawls properly adjusted on the normal "front" of the saw.

Without the use of the anti-kickback pawls and of course the splitter, I think anyone is asking for trouble. That's probably the basis for a lot of the "safety questions" that come up... that and the continued advice from some sources that says, "push" cut when making a crosscut (to avoid blade climb). Some of these practices leave me scratching my head!

CWS