# Dado on RAS...?



## Nickp (Dec 4, 2012)

I have a Craftsman 8 1/4, 2 1/2 HP RAS and have had it for quite a while. I am very comfortable with it having used it for cross-cuts, rips, miters, and even tongue and groove (on it's side). I have not always had the tool inventory I have now...

I have read quite a bit on this and other forums regarding the use of RAS for ripping as being unsafe...I get it. I guess that shows I'm paying attention...

I also pay attention to the saw adjustments. I don't use it every day and I find it reassuring to check alignment of travel, blade angle perpendicular, no sway in the arm, etc...

I don't have a good enough table saw (yet) to cut dados and have been using my router and a pair of (zero clearance) guides to keep the cut parallel and for sizing. I typically do two passes with a 1/2 in straight or spiral bit.

My question is the safe use of a dado blade on this saw. The HP seems sufficient, the size would accept even an 8" dado, the guard and housing seem sufficiently large enough to accept a dado and the arbor is long enough.

...but is it safe to do so. I'm counting on your pro/con experiences and advice. And if so, shall I use an 8" dado or smaller...?

Thank you in advance...Nick


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## Cherryville Chuck (Sep 28, 2010)

If you have a dado stack then I would try it, very carefully of course and maybe in stages to start with Nick. I used the RAS a lot for a while when I didn't have a table saw to use and while they leave a bit to be desired in that capacity they will get the job done. I remember when Sears started selling their molding heads they were only recommended for use on the RAS so I don't see why a dado stack wouldn't work.


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## jw2170 (Jan 24, 2008)

Hi Nick, I have seen a number of wood workers use their RAS for cutting dados. I do not see why it would not work.


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## Semipro (Mar 22, 2013)

It is not a problem as long as you are making a dado ( cross cut) keep the wood tight against the fence,
Do not try a groove it well pull the wood out your hands.


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## herrwood (Apr 19, 2014)

No problem with dados on a ras I use the Freud 8" sd208 set and it works well just keep a good grip on the board. Dados are one of the main things I use my ras for as my table saw does not do dados. 
I also use use it as a disc sander and with a 8" wire brush (wear eye protection) it cleans up rusty tools quickly.


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## Nickp (Dec 4, 2012)

Thank you, Charles, James, John and Ed...I thought as much given my own experiences on the RAS. 

John...a bit puzzled by your comment on grooving with the grain. I have thought that paying attention to feeding AGAINST the spin/tooth would be no different than cross-cutting or routing, for example. The saw has a stop that prevents the piece from lifting and I've used appropriately placed featherboards to hold the piece correctly. The saw also has a riving roller wheel on the outfeed that adjusted properly seems to keep the cut end positioned properly. Admittedly, I've used the table saw to do this since purchasing one.

Not arguing your point, maybe just trying to figure out if I've been lucky or it's been my precautions have kept me out of harm's way. I'm a firm believer that confidence in the use of a tool is a factor in keeping one safe and I don't want to lose that. I also don't want to put myself in a position of being "over-confident".

Your continued thoughts on the subject are appreciated...

Thank you all, Nick


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## Nickp (Dec 4, 2012)

herrwood said:


> No problem with dados on a ras I use the Freud 8" sd208 set and it works well just keep a good grip on the board. Dados are one of the main things I use my ras for as my table saw does not do dados.
> I also use use it as a disc sander and with a 8" wire brush (wear eye protection) it cleans up rusty tools quickly.


Ed...thank you for the recommendation on the Freud...


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## carlp. (Nov 3, 2012)

*dados on a ras*

Hi Nick I have 3 ras saws 2 with dados and one for trim cutting running on my production line. never had a problem all are b&d 2 7740 and 1 7770. regards carl


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## john60 (Aug 30, 2014)

I have done a few dados on my De Walt radial arm without issue. 
I use a Forest woodworker I blade for regular cutting This is the blade recommeded by Mr Sawdust. regular blades for radial arm saws are few and far between. The have a different rake angle to reduce kickback. ( the Mr Sawdust book has a lot of good information for the radial arm saw including making a good table).


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## roxanne562001 (Feb 5, 2012)

I use an older dewalt 10" radial arm saw with both stacked dados and wobble set I never had any problems with either. It works great on cross cuts a little bit tricky when doing rip dados but it works either way.
Roxanne


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## Herb Stoops (Aug 28, 2012)

Years ago on the job site all we had was a Radial Arm Saw and a skill saw and we used the saw with a dado blade to cross cut dadoes in 2X6's and 2X4's. As I remember. it was safe enough, you just had to lean into the saw to keep it from overpowering you and grabbing trying to walk across the board. 

It would be wise to sample taking smaller depth cuts if you are cutting over 1/4" deep before you go to a full depth cut. 
We used to cut rabbits along the edges of long boards too,and it was as safe as a table saw if you set up with feather boards and a push stick. 

I have a Craftsman 10" RAS set up in my shop that I use for all my cross cutting up to 14" wide. It has a 80t Freud blade and cuts perfectly square. Sure a lot easier to cross cut a 12" wide X 4' long board square on the end than anything else I have ever used. And the saw only cost me $35.00 on Craigslist.
I haven't had to cut any dadoes in long stock recently. but it would be an option if I had a lot to do.
Herb


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## Herb Stoops (Aug 28, 2012)

Hi Semipro,
The RAS does a good job of dadoing with the grain (ripping) ,but you have to feed it against the rotation of the blade as you would a table saw. We did miles of rabbiting on the job site over the years before we had a table saw. and a rabbit or dado is a lot easier to handle on a RAS table than a table saw for 8'-20' lengths of material.

Herb


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## Dmeadows (Jun 28, 2011)

I have cut many dados with my RAS. Should not be an issue, since you seem to know how to use a RAS properly. 

If the saw pulls the board out of your hand... sorry, but you don't know how to use a RAS I would strongly recommend that anyone having that issue should NOT use a RAS for anything till they get some proper instruction. Just my opinion, but... it is a Shop Safety sub-forum!


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## DaninVan (Jan 1, 2012)

I agree with all the _pro_ RAS comments, especially the long length issue.
Having said that, I still have the scar on my hand from using a buddy's RAS, with a wobble blade. A feather board to hold the prefinished wood (slick surface) against the fence would have prevented the accident...but that's history, eh?
First and last time I've ever used a wobble dado blade.


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## Nickp (Dec 4, 2012)

Thank you all for your comments about safety...exactly what I needed...

Follow-up question...in purchasing a dado stack, zero or negative rake ?

Thanks again...Nick


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## Dmeadows (Jun 28, 2011)

Nickp said:


> Thank you all for your comments about safety...exactly what I needed...
> 
> Follow-up question...in purchasing a dado stack, zero or negative rake ?
> 
> Thanks again...Nick


Negative would be better for the RAS.


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## Dmeadows (Jun 28, 2011)

DaninVan said:


> First and last time I've ever used a wobble dado blade.


Wobble dado blades are scary to me on several levels, regardless whether used on a RAS or not, Dan. I have one, but only because it was given to me. It hasn't been used much and likely won't be.


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## Herb Stoops (Aug 28, 2012)

Wobblers scare me to death. Back in the 60's I bought one to use on my craftsman contractors saw and just the noise and sight of that star shaped thing terrified me. I was determined to master it, but it was not a carbide cutter and did a rough job of dadoing. It hung on the wall for years and has disappeared into the junk pile . 

Have any of you heard of using a dado on a worm drive skillsaw? 

Years ago when the California framers came to town to cash in on the housing boom here the roof framers (they were all piece workers), brought this 10" worm drive skillsaw that had an extended shaft for a dado blade set. It also had a wide guard over the blade. 
They would bunk up all the rafters on edge, snap a line across the pile and set the saw on the desired angle to match the pitch of the roof and nail a 1X4 guide across and dado the birds mouth into all the rafters with one cut.

Herb


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## Nickp (Dec 4, 2012)

> dado the birds mouth into all the rafters with one cut


.

Now that's efficiency...the birds mouth cuts on my first shed's rafters (when I was a wee tot) looked like different species...


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## Nickp (Dec 4, 2012)

Dmeadows said:


> Negative would be better for the RAS.


Thanks, Duane...


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## timbertailor (Oct 4, 2009)

I think me and Herb have the same saw, blade, and set up.

The RAS is still an integral part of my shop and when I am doing a long production, I do not hesitate to set up the RAS with a dado blade. Never used a wobbler.

Not even sure they make RAS specific dado sets. Let us know what you find please.


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## Nickp (Dec 4, 2012)

*Update...dado on RAS*



timbertailor said:


> I think me and Herb have the same saw, blade, and set up.
> 
> The RAS is still an integral part of my shop and when I am doing a long production, I do not hesitate to set up the RAS with a dado blade. Never used a wobbler.
> 
> Not even sure they make RAS specific dado sets. Let us know what you find please.


So...after giving some reasonable but not extensive research on the topic on various sites...
1. Most are comfortable using dado's on RAS
2. Almost all recommend zero or negative (-5, -15) hook on blade (this to minimize the risk of kickback)
3. Most advertisements that include "anti-kickback" designs do not make it easy to find that it's negative hook that provides it)
4. I did not find mfg's that specifically market a dado for ras's (although Sears mentions the use of "dado accessory" for their 10" model" but couldn't find that they make one)
5. Most find the RAS as being unsafe for anything except cross-cutting even though all RAS's allow twisting the blade to all axis
6. Some that use dados on RAS would never use wobblers (bad experience, vibration, bearing abuse, just plain scared of 'me, engineering abomination, etc)
7. Most users always express caution when using dado on RAS
8. Some users don't even think about safety...they just do it
9. (On most forums) seasoned - *not old * - express their use of dados in an educational manner giving advice with the poster's safety in mind and usually commensurate with poster's experience
10. Some forums have much debate on the topic
11. Did not look enough into many model saws but did find that their arbors are sufficiently long enough to accommodate (at least the 10" models I looked at)

I would add that each needs to examine their own comfort level (as was recommended in an earlier response to my post)

I've stopped looking for more info and have made my decision...SD-208 from Amazon, unless any other suggestions on who to buy from...

Thanks to all so much for all your input and advice...time to make the tall kitchen cabinet for the unused space by the door...

Nick


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## Herb Stoops (Aug 28, 2012)

Nick,
Your conclusions are all founded. May I humbly add some comment? 
The router does a good job of dadoing,both on a router table and freehand as long as you use a guide bushing or bearing on the bit and a straightedge guide for free hand. Be sure also to feed the router against the rotation of the bit when doing hand held dadoing other wise the router has a mind of its own and will want to wander away from the straightedge. 
Dado sets are quite a bit more expensive than router bits and sometimes are a hassle to set up on a table saw. they have bits sized especially for the new plywood thicknesses.
I prefer using a router when dadoing plywood cabinet side,it is less awkward to use a route than feeding wide panels through the saw.
I have both an Infinity dado set and a Freud, they are both good ,really sharp so wear gloves when you install them on the table saw.

Herb


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## Nickp (Dec 4, 2012)

Thanks, Herb...to date I've been using a 1/2 inch straight or spiral bit with parallel guides and handheld router. Couple of passes and done. It works well and have been very happy but wanted to add to my experiences with my RAS...for long grooves I've been using my edge guide and taking two passes for the width. I enjoy using the router and expanding my horizons...

Thanks again...Nick


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## Phil P (Jul 25, 2010)

Hi Nick

I read your conclusions with interest and I'd like to comment on them, if I may


Nickp said:


> 5. Most find the RAS as being unsafe for anything except cross-cutting even though all RAS's allow twisting the blade to all axis


I agree, up to a point, but I'd point out that the difference between a 10in home shop machine like a Craftsman and a 12in or 14in industrial machine such as a Wadkin or Original Saw (the successors to the DW industrial line _in the USA_) is absolutely massive. Industrial saws don't twist at all, but even hobby models can be stiffened-up making them much more rigid and therefore safer/more accurate. The trick is to brace the area below the tavble where the rise/fall mechanism is


Nickp said:


> 6. Some that use dados on RAS would never use wobblers (bad experience, vibration, bearing abuse, just plain scared of 'me, engineering abomination, etc)


Wobble saws have always been regarded as a dangerous piece of kit by wood machinists, but the other negative aspect is that they don't cut a square bottomed groove. With a good quality set (such as the Omas TCT set designed for use on spindle moulders, for example) the balance issue isn't really that bad because there is more weight in the blade "washers" than the blade itself

The safety aspect of dado heads on a RAS is that almost like a plunge router - your hands should be used so that they are out of the way of the blade which is intrinsically safer than when they are used on a table saw _unless_ you are able to install a suspended overhead blade guard or something similar. When cutting multiple housings (dados, grooves) in something such as a bookcase I can attest to the RAS approach being quicker and safer than anything you'll ever do on a table saw

Good luck with your further work in this area

Regards

Phil


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