recommendations for cutting shallow grooves in narrow wood strips

wengang1 · 07-31-2012, 10:29 AM

I'm building a crib for my daughter and I'm stuck on a task that's a little beyond my ability.

I have a bunch of wood strips, 3/4 thick, 1 1/8 wide, and varying lengths from two to five feet.

These wood strips need to have flat shallow grooves (1/16 inch for some) cut in them lengthwise as tracks the width of the various pieces of wood that will be set into them (45/64 for some 27/64 for others).

The design plans I bought for the crib instruct to use a dado blade on the table saw with the fence. Well, my table saw is a cheap one and it only accomodates up to a 3/8" dado. Also in my previous experience using the dado blade, it always tore the wood out in the same spot, virtually every time. Also, I'm not confident I could get it cut to precision making multiple passes.

So on to the router. Well, I have a router but no table. Actually, it's a Dewalt, and I've never seen a table made just for it. Anyway, last night I tried to rig a fence system with some hardwood pieces spaced 1 1/8 inches apart and a fence piece on top to hold the router centered. Then I put in a 3/8 flat bit (or square bit) and set it to 1/16 depth, just for a test. The results were ridiculous. The router didn't stay flush against the fence, the wood strips vibrated and moved a bit, and you can imagine what the result looked like.

Assuming I'm not buying a new table saw, and would prefer not to buy a new router/table, how do I make these cuts?
Also, the directions say the groove widths have to match exactly the width of the plywood that's going into them. That's why the widths aren't clean (like 3/4). I'm wondering if I can cheat it 1/64 and go 23/32 and 7/16. It would be easier to get the dado or a router bit to those exact widths, and this is all going to be glued anyway.

goosebarry · 07-31-2012, 01:22 PM

I never use dado blades except for rough work.
Use your saw to cut along the sides of the dado, then use a sharp chisel to chisel out the middle. If you are careful you could also remove the middle using a router. It is better to cut a little narrow then clean up your line to fit the stock. It is very easy to take a big gouge when trying to clean up the edges with a chisel, so I create mini sanding blocks to percisely fit each piece.

You can get that factory fresh look with 1/16" precision or 1/32" will be more then adequate. The thickness of the plywood probably varies by more than 1/64 of an inch and will vary that much with changes in humidity and temperature. Also, don't fret every joint, only those that are visible. For dados cut narrow and sand to fit your stock.

If you want to see how to do precision joinery watch Rough Cut Woodworking with Tommy Mac on PBS.

Millertyme · 07-31-2012, 04:49 PM

I'm not understanding why multiple passes on a table saw would not work.

woody4249 · 07-31-2012, 06:30 PM

The problem here is not the saw or the dado blade or the router it's the way the wood is moving against the fence and the bed of the table. Unless you have a "Fisher Price" Brand tool that is?

What you need is a couple of feather boards
Take a look at this page
https://www.google.com/search?q=tabl...w=1280&bih=832

My preferred tool would be a router with the correct sized bit

Mike

**oh'mike** · 07-31-2012, 07:18 PM

You can make a dandy router table in little time---

get a scrap of 1/2 inch cabinet ply---2 feet x 3 or 4 feet long---

Use the base plate of the router for a drilling template---roughly center the plate to the ply---mark and drill the mounting holes--and center hole for the bit---Get some longer flat head screws and mount the router--

Use your table saw to rip two pieces of scrap plywood the length of the new table--about 3 1/2 to 4 inches wide----glue those and nail--add a couple of blocks to keep them square--

Cut a notch for the router bit---screw the left end with one wood screw---use a clamp on the right end---there---router table---

Use feather boards for holding the work---and a good safe pusher block.

Daniel Holzman · 07-31-2012, 09:35 PM

I would consider making multiple passes using the table saw and a rip blade. However, due to the narrow width of the pieces you are working, it can be very dangerous ripping these pieces. You need to have a good fence that is parallel to the saw blade, a very sharp blade (I only use carbide blades on my table saw), and a special jig designed for ripping narrow stock. This could be a Rip Strate, or often I use a safety pusher (mine is called the Gripper) that allows the operator to push the wood forward, while at the same time exerting pressure to keep the wood against the fence. The pusher passes over the blade, keeping your hand safe. Be very careful, narrow stock can be very hazardous to work with.

wengang1 · 08-01-2012, 12:56 PM

Goosebarry

That's a lot of good information. In all my past experience. I cannot use chisels. I've bought a couple of sets, but all I do is tear the wood up and get frustrated.

wengang1 · 08-01-2012, 01:00 PM

Millertyme, Woody4249

I think the multiple passes is a good solution, i just don't have a lot of confidence. The primary issue is my "Fisher Price" table saw. It's the one thing in my workshop that I skimped on, and I've had plenty of opportunities to regret it.
I have a feeling the wood is going to move off the fence, vibrate up and down, or snag and kick back and there's just too little room for error.
I guess I could spring for the featherboards. I've seen them at Lowes. I just didn' t know exactly how they were used or if they'd fit in the miter slots of my table (only 3/8" wide).

wengang1 · 08-01-2012, 01:05 PM

Oh'Mike

I saw a couple of videos on Youtube of guys who did that. I guess what I need to do is go to Lowes and get the same size screws (only longer).
And I still don't quite see how to use it, since I've never had a router table.
On the router table, are you running the piece along the open bit with your fingers?
Some of the pieces I have to cut are 5/8 x 5/8 strips. I'd hate to have it jump and bring my fingers across the bit.

wengang1 · 08-01-2012, 01:08 PM

Daniel Holzman

Exactly what I'm worried about.

I don't know what kind of pusher you're using, but the ones I've made from wood scraps have occasionally let the piece bounce once the front starts clearing the blade. Maybe I need a featherboard on the fence.

woody4249 · 08-01-2012, 03:56 PM

You can make a feather-board yourself from a piece of 1x4. Make it long enough so that you can clamp it to the bed of the saw or router table and also to the fence. As you push the workpiece through it should spring the leaves to the feather-board and not allow the workpiece to come back at you holding it to the fence and table.
See attached photo of one I made last week.

**oh'mike** · 08-01-2012, 07:33 PM

Woody had the feather board pictured---one of those above the cutter--another mounted to the table to hold the work to the fence--a pusher that is shaped to hold the piece down-

-I'll see if I can find a picture---I make the pushers and feather boards with a band saw--But you can purchase the premade---

**oh'mike** · 08-01-2012, 07:35 PM

**oh'mike** · 08-01-2012, 07:37 PM

First and third pictures work well--do not use the center pictured one---wood will flip up

wengang1 · 08-03-2012, 09:11 AM

OK!
I made some featherboards (not as neat as yours) and I gave the table saw another try. It did the job okay, but the grooves were not smooth, and would have required a lot of sanding.

So I built the router table. It took some figuring out, but it works great! The finest cuts were all to precision, and the wood was as smooth as if it had been sanded.

I did find that the bit would occasionally grab the smaller pieces and sling them through like a rocket. Still haven't solved that. Also, sometimes when the end of the wood clears the first side of the hole, it springs down a bit, but not too serious. And using the screw and clamp method you described, I can't figure out how to set the fence distance. I've been using scraps and measure-adust cycles to set the depth and fence distance. And lastly, I'm concerned the plywood my start to sag eventually (it's 3/4 about 16 inches by 4 feet). I'm thinking of putting some lumber on edge under the table to prevent that. Sound right?

And I glad you told me about the push stick. I actually made the middle one. I don't have a bandsaw. I used a jigsaw. The first time I used it, it knocked several teeth off the fence featherboard. Live and learn.

Anyway, I feel like I took a big step forward in woodworking this week. I'll think twice before I just buy something at Lowe's now.

Thanks.
Photo is attached.