Safe Way of Cutting Grooves for Cabinet Door Panel

[Bob Deroeck]

I'm making shaker style cabinet doors with the stiles full door height and the rails mortised into the sides of the stiles. I can cut the grooves for the door panels with a table saw and dado blade or a straight router bit on a router table. The groove can be cut the full length of the rails since they are mortised into the stiles. The groove on the stiles need to be started a bit in from the end of the stile and stopped a bit before the other end so that it is not seen when the door is open. My question is "what is a safe way to cut the groove in the stiles"?

I'm concerned with kickback on the tablesaw if trying to "drop" the stiles onto the top of the spinning dado blade. Also, I can't use my table saw splitter on this type of cut.

I have 1/4" upcut and downcut solid carbide router bits. It seems to me that dropping the stile onto a spinning router bit could be problematic, but maybe I"m just being overly conservative. Obviously, I haven't done this type of thing before.

I'm thinking about drilling shallow 5/16" diameter holes in the stiles at the start and stop points for the groove. Then I can place the start hole of the stile over the router bit before turning on the router.

Any suggestions and advice would be appreciated.

Bob DeRoeck

[Darius Ferlas]

Why don't you use a slot cutting bit (http://www.amazon.com/Freud-63-162-4-Inch-Cutter-16-Inch/dp/B0002TUD1U/ref=sr_1_1?s=hi&ie=UTF8&qid=1366664296&sr=1-1&keywords=slot+cutter).
They come in all kinds of sizes.

[Peter Aeschliman]

Yeah, a slot-cutting is the best bet. But I wouldn't worry too much about dropping the workpiece down onto the spinning bit. It's just a plunge cut, which we all do all the time with a handheld router. Just use feather boards, keep your hands back from the bit, plunge slowly, and make multiple passes, raising the bit a little at a time. If you're worried about it kicking back, you can always set up a fence stop on the infeed side behind the end of the workpiece, such that the end of the workpiece is resting against it as you plunge. This would add stability. Keep in mind, it could kick forward as well, since the bit is cutting on all sides. This is the most dangerous scenario, since it could pull your hands forward. So use a guard over your bit if you can, and use a push stick.

Definitely don't do this on your table saw- not only is it less safe, it will require a lot more cleanup since the groove will leave a lot of material behind at the ends due to the large arch of the blade.

All in all, I'd use this as an excuse to get yourself a good slot cutting bit. It's bit you'll use often.

[glenn bradley]

I use stops on the router table fence and start at 1/16" of depth, butt the end of the material against the beginning stop, drop on and move the material to the end stop. Raise bit 1/8" and repeat till final depth.

[Sam Murdoch]

Either with the TS or router table you rightly need to consider the potential for kick back. My table saw technique is as follows:

1) Remove the riving knife.

2) Raise the blade or dado set up to the finished slot height above the table.

3) Mark the TS fence with a clear vertical lines that shows the beginning and ending limit of the cut that the RAISED blade will make. I do this by setting a piece of wood perpendicular to the fence - move it to the blade (machine off, of course) until the blade touches the wood piece. Transfer that spot to the table saw fence at the front and back of the blade. You now know the extent of the cut of the TS blade raised to the top height of the slot you will cut.

4) Mark the intended near end of the slot on the stiles with a clear pencil line or blue tape (just mark it clearly) so that as you pass the stile over the blade you will clearly be able to see when the lines on your stile corresponds to the lines on the fence.

Please Note - It is best if you are centering the slot in your stiles. If they are off center you will need to pay close attention to which face of the stiles rides against the fence. Best to make it very obvious which face is which on all your stock.

NOW - THESE NEXT STEPS ARE VERY IMPORTANT SAFETY STEPS -

5) Lower the blade a precise number of turns to get it below the table. Count 3, 4 or 5 turns and note the clock position (in 1/4 turns) of the face of the TS blade height adjustment wheel.

6) Run a few sample pieces into the running blade to make certain that the cut is the correct width and height and position relative to the face of the stile. When you are confidant that your set up is good -

7) Set up feather boards to hold your stiles against the fence and also against the table. You may need to add an auxiliary fence in order to get enough height to properly secure the top feather board.

8) With the stile properly secured with the feather boards AND THE BLADE BELOW THE TABLE. Move your first marked stile over the blade until the mark on the outfeed of the fence corresponds to the mark on your stile.

9) Start the saw - raise the blade to the correct number of the predetermined count (it is now at the correct height - or very nearly) - feed your stile over the running blade STOP PUSHING THE STILE WHEN THE MARK ON THE END OF THE STILE CORRESPONDS TO THE MARK ON THE FENCE NEAREST TO YOU.

10) LOWER THE BLADE to the count or stop the saw whichever is easiest all the while make sure that you are in control of the work. In any case you will need to lower the blade before passing the stile all the way through. Pay attention to the number of turns as you lower the blade. Count out loud if that helps.

11) Square the end of the slots with a sharp chisel.

I have never had any issues doing it this way and using a sharp blade or dado set. Drop cuts are doable but very dangerous the element of risk goes through the roof especially if you are running multiple pieces.

You can use the up cut bit on the router table in essentially the same way but how to do this with the bit spinning horizontally into the wood is too risky in my opinion because the wood is not secured by a hold down of any kind. I'll be curious to read other answers to your question. You can always just run all your parts through the saw with no stops then just fill the ends. For paint grade doors this is a very safe and acceptable way to achieve good results. Also possible with stain grade - depending on who is looking :).

Be safe. Keep your wits about you.

[Tom Wassack]

Greetings from NC!
I just built Shaker style doors for my shop cabinets and used a haunched tenon on the rails. This allows you to groove both the styles and rails with the same setup (table saw or router). I then assembled the doors with a draw-bored mortise and tenon joint.

Regards,
Tom Wassack
Asheboro, NC

[Jeff Duncan]

I'm pretty comfortable using machinery but I still tend to go with what I think of as the safest practical way to get things done. So although I've done it, I prefer not doing stopped pieces on the table saw. A router in a table with a slot cutting bit is a safe practical way to do your slots. I would do it on one pass to keep it as accurate as possible....more passes = more opportunity for sloppy fit. I would set the fence to the depth you need, set the height of the bit, and then attach a starting block to the infeed side of your fence. The block makes it much safer and more accurate than free handing. Place your stile against the block and gradually ease it into the cutter, push it the full length of the cut, (which can be marked with a piece of tape or a pencil line), then pull straight out away from the fence. This is the same technique I use to do stopped flutes on the shaper and it works better than anything else I've tried.

good luck,
JeffD

[Dave Richards]

Why wouldn't you make haunched tenons like Tom suggested? That would be the common and traditional way. You won't have to drop the work onto the cutter nor raise the cutter into the work.

[Stephen Cherry]

I vote for the router with spiral upcut bit, and a fence with stops. One advantage of a router bit is that it can cut it's way out of binding the workpiece because it can cut in all directions. The table saw, on the other hand, has poor ability to cut from the side, particularly as the depth of cut is greater than the height of the blades teeth. So, it seems to me, that if the workpiece gets out of alignment, the router bit will cut sideways, resulting in a miscut piece of wood; while the table saw in a similar circumstance, would launch the piece into orbit.

Also, the spiral bits are much more stable while cutting than strait cutters and worth every penny.

[Erik Christensen]

I must be missing something really obvious. I make shaker panel doors with a matched set of cutters - one grooves the rails/styles full length and the other makes the matching tenon coping cut on a sled for the ends of the rails - the end result is your rail tenon = panel thickness. What am I not getting here?

[Dave Zellers]

He doesn't want the tenon to show at the top or bottom of the door.

[Bob Deroeck]

Thanks for all the throughtfull replies.

It looks like the best option is a slot cutter bit. I'll order one tonight.

Tom's suggestion of using haunched tenons is a good option. I wish I had spent more time thinking through the entire joining/cutting process before I started cutting wood. Next time, there will be more time spent during the design and planning stage of the project.

Sam's detailed procedure using a table saw and Glen's approach using a router both look to be safe options. I'll go with the slot cutter to reduce the chances of ending up with sloppy grooves from taking multiple passes for each groove.

Thanks.

Bob DeRoeck

[Lee Schierer]

I'm concerned with kickback on the tablesaw if trying to "drop" the stiles onto the top of the spinning dado blade. Also, I can't use my table saw splitter on this type of cut.


Any suggestions and advice would be appreciated.

Bob DeRoeck

DANGER: Do not ever attempt to lower a piece of stock onto a moving table saw blade it is extremely dangerous. If you want to do a blind cut, determine the correct blade height and then lower the saw blade counting the exact number of turns required to lower it. Then place your stock on the saw with a stop block behind it, start the saw and then raise the blade the same number of turns you lowered it. When you complete your cut, turn off the saw and waith for the blade to stop before attempting to remove the stock. Repeat this process for each cut.

Or use a router with pre drilled start and stop holes.

[Thomas love]

260727260728260729Slotting bit on router table, start cut in mortise stop in mortise at other end very simple I have done it more times then I can remember.

[Darius Ferlas]

He doesn't want the tenon to show at the top or bottom of the door.

For this application, IF the panels are to be plywood or similar dimensionally stable material, I wouldn't even worry about M/T. Longer dowels (3" or more), combined with the panels glued in strategic areas and epoxy used for the dowels, the job would be much faster and sufficiently strong.