Newbie question: How to make finger joint cut

[Scott Kuhn]

I have almost no experience with woodworking and am wondering which tool would be best to make the following cut. (I can make it fairly well w/ hand tools, but curious what the best approach would be with power tool).

I have a piece of poplar 1/2" thick, 9" long, 4.5" wide. I want to cut a rectangle out of the corner of the board to make a finger. I'd like to remove 1/2" along the 9" edge and 2.25" along the 4.5" edge. I need to be able to make it close to perfectly square, and to do this repeatably on multiple boards.

Visually, here is what I want to do (not to scale):

Before: xxxxxxxxxxx xxxxxxxxxxx xxxxxxxxxxx xxxxxxxxxxx

After: xxxxxxx xxxxxxx xxxxxxx xxxxxxxxxxx

I'm guessing I could do this on a table saw, for this case, since I can raise the blade 1/2" above the table and use a dado head blade. However, what about the more general case, if the smaller dimension of the rectangle that I want to remove was larger than the max height of a tablesaw blade?

Thanks for any suggestions.

-Scott

[U-CDK_CHARLES\Charles]

That's called a rabbet. Same root as "rebate" . . NOT the animal (which isn't a rodent, despite having similar teeth, but that's another discussion). Some older "Rabbet planes" are labeled "Rebate planes"

If your rabbet is deeper than 3/4", you should think about WHY you need to rabbet that deep. There's probably a better way to accomplish what you want in those cases.

Tools? Almost anything. Mark the width and depth with your marking guage. Cut with the bow saw, fitted with the appropriate blade for the task at hand. I use a mirror so I can stand in a comforatable position and still see what I'm doing.

My first attempt at tenons (imagine four rabbets) used exactly that technique, and it was plenty "square". Practice on scrap. Poplar is just about the easiest hardwood to practice on.

I practiced on red oak before I did my actual pieces. Took about three practice runs before I "got it."

Good luck

Charles

[Scott Kuhn]

Charles, Thanks for the info.

I may not have explained what I'm trying to do clearly enough. In my case, I want to remove the rectangle all the way thru the whole thickness of the board. Is it still a rabbet in this case?

When I'm done, the whole piece will still be 1/2" thick but shaped like shown in the diagram below (looking at the board from the front)

Before:

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

- -

- -

- -

- -

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

After:

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

- -

- -

- -------

- -

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

(In this diagram, the rectangle that I've cut away is the upper right corner.)

I wish it were that easy to get nice square angles with wood. ;)

In case you wonder what I'm doing, I'm trying to build a box. It is the first project in a book by Aime Ontairo Fraser called "Getting Started in Woodworking". The joints for the box are finger joints, as she calls them, which are then strengthened by inserting a dowel pin later in the process. The adjacent board would have the rectangle removed on the bottom half of the board so they will fit together.

--Scott

[bridger]

there's that.

if you are trying to do what I think you are trying to do, it's pretty different from what I'd call a finger joint. here's what I'd call a finger joint:

that what you are after? if it is, there are a number of ways to go about it:

no

ascii art rarely communicates well. if you have a scanner or a digital camera or a drawing program on your computer either capture the images from the book or draw us a diagram and scan it or whatever and post it to alt.binaries.pictures.woodworking.

that sounds more like a half lap joint. it hardly seems like it would add much to the strength of the box. I suspect that I'm still not understanding what it is that you are trying to do.

[patriarch]

scott_d [e-mail] (Scott Kuhn) wrote in news: [e-mail]:

I'm guessing that the limitations of ASCI art, and relative unfamiliarity with terminology, are going to be a problem which continues for a little while.

You have one pretty good book - let me suggest another: Taunton's "Complete Illustrated Guide to Joinery", by Gary Rogowski, published withing the last 18 months or so. Well written, tons of process photos, and almost every conceivable means of safely producing common and not-so- common woodworking joints.

It will cost you about 20% of the price of the router you're likely to be shopping for next, by the way. For that, see

for some of the best information you could want.

Have fun with this. There are friends here.

Patriarch

[Scott Kuhn]

No, that is what i will eventually be after, but right now it's much simpler...

I took a few pics and posted them here:

now that it's clear what joint I'm trying to make, how would you make it accurately and repeatably? I stopped in my local Woodworking store and asked a guy there, and he said he'd do it on a jigsaw or maybe a bandsaw.

Thx to the previous posters for the resources and info. The book by Rogowski mentioned by Patriarch looks great and is now in my Amazon.com shopping cart.

--Scott

[patriarch]

scott_d [e-mail] (Scott Kuhn) wrote in news: [e-mail]:

If the pictures are the ones that showed up earlier this evening on abpw, then mostly the tools you need to cut this simple joint are readily available. A good little saw, on which you can spend anywhere from $10 up to more than $100, a square for marking the cut lines, and either a sharp pencil, or a razor-type knife.

Since you're starting out, pick up the hobby saw marketed under the name ZONA. It has replaceable blades, cuts with a very thin kerf, and is the maybe $10 model mentioned in the previous paragraph. And, lest you think that it has no class at all, it is the handcut dovetail saw of choice of one of the graduates of the College of the Redwoods woodworking types that regularly hangs out with our woodworking club. Or a Japanese style pull saw, or similar.

Maybe a chisel to clean up the cuts. And a block plane to trim the joints to close fit after glueup. Or use sandpaper wrapped around a block of wood.

Now, the question of repeatability comes up. How much repeatability are you after? Do you want to cut 4 of these joints? Or 400? Or 4000? If the answer is 4, then use the hand tools, and practice, and work with care. If you want to do 400, then a jig or fixture on the table saw or router table will help you cut them repeatably, quickly, and fairly safely. If you need 4000, then find Morris Dovey, and have him program his massive CNC robotic cutters, and sub out the job. ;-)

You see, woodworking is a bit like economics. There are a few questions, many more answers, and no one can really prove any of them wrong. But things DO tend to get more complicated than we ever intended, when once we started.

Enjoy the learning experiences. That's where the value comes, in my limited experiences. That, and making people smile.

Patriarch

[Andy Jeffries]

I'm not far from a newbie (only about 6 months woodworking experience) but as far as I know, that joint is called a half-lap joint.

I've gotta cut about 40 of them soon (in 2x2 for making a frame) so I'll be trying to find a repeatable method too. In fact, I'm probably just going to cut them all by hand as:

a)I'm a bit shaky with a router (it is a very cheap router)

b)it's only for a frame underneath an MDF constructions.

Cheers,

Andy

[bridger]

Scott-

what tools do you have?

[J. Clarke]

As to how I'd make that specific cut "accurately and repeatably", IMO it's practically made to order for a radial arm saw. Two passes, one with the blade vertical to cut from the edge, one horizontal from the end, stack your pieces and you can do a dozen or so on one pass depending on thickness.

But if you don't have a radial arm saw then you'd have to go out and get one to use that approach, so it's probalby not cost effective for you.

The problem with questions like this is that there is no "right" answer. The "best" way to do it depends on too many factors. If all you've got it a Swiss Army Knife and you're a broke student with plenty of time then you can do it, very carefully, with a Swiss Army Knife, sharpening it on a coffee mug in the cafeteria as needed. On the other hand, if you're the CEO of Delta you hand the piece to an engineer and tell him to whip you up a machine that takes whatever he has in at one end and produces finished parts at the other (OK, I'm exaggerating--he'd probably just pull a radial arm saw off the line if he didn't already have one).

Part of the "art" of woodworking is figuring out how to do what you need to do with what you have and failing that what's the best thing to do about it--the "best thing to do about it" is not necessarily get a tool optimized for that one job--there may be one that does it "good enough" and does a lot of other stuff that you've been working too hard at with what you have.

You asked how to handle a cut of that nature that is too deep for the blade depth on your table saw. Many ways. You could use any of several varieties of hand saw, a band saw, a jigsaw, a scrollsaw, etc. If the stock thickness is less than twice the cut depth of the longest bit your router will handle then you could route it and clean up the corner with a chisel. If you're desperate enough you could drill multiple holes along the cut line then smooth it with a chisel.

[U-CDK_CHARLES\Charles]

Hmmmm . . .

I don't see a lot of glue surface there.

"Glue surface" is long-grain. The only "long grain to long grain" contact in that joint is where the two horizontals meet.

That's a weak joint.

There's a reason why we're still cutting dovetails, finger joints, and mortises and tenons--LOTS of glue surface.

If you have hand tools, you want dovetails for that application.

If you've a table saw, use a dado to cut finger joints.

If you've a router, either finger joints OR dovetails.

If the joinery won't show, I've made similar joints with internal glue blocks screwed into both sides of the joint--fast and easy, though none too attractive.

[Scott Kuhn]

Yeah, that sounds good. In fact, the way I've made a couple of these joints so far is as she recommends in the book, which is using a Japanese Dozuki saw and then a chisel to clean it up. That's the part I find hard - getting the notch nice and square with the chisel. But I think you're right, with practice it'll get better.

I only need 8 of them, so I guess doing it by hand is the best way for now. I was just wondering mostly, is it possible to make this particular cut on a router or TS and you've answered that in the affirmative.

Thanks very much for the input!

--Scott

[patriarch]

"U-CDK_CHARLES\\Charles" wrote in news:9dcJc.43412$ [e-mail]:

I think that this is a smallish decorative box, primarily made for practice, in a beginning course of woodworking. Based on the cited author, my strong suspicion is that dovetails are on the agenda, a couple of chapters later.

BTW, if you were to pin these joints vertically, say with a small dowel, or brass rod, they would probably hold up better, in this limited application.

Patriarch

[Scott Kuhn]

I was looking on amazon.com at the "Complete Illustrated Guide to Joinery" book mentioned in this thread, and using the "search inside this book" feature you can see thumbnail photos of many joints. Based on that, I'd say the joint we're talking about here is called a "halved joint". A half-lap joint is similar, but half the thickness is removed from each board, whereas in the halved joint each board retains it's full thickness. Have a look at those pictures and see if you agree:

I hope you'll let us know how it goes. I'd personally be happy to do them by hand, it's quiet, safe, and satisfying, but I gotta admit, if I can do them _better_ with a router....

Regards, Scott

[Scott Kuhn]

Right now, only hand tools save for a 12" Makita Compound Miter Saw.

Hand Tools: * Dozuki saw * Full set of chisels * Block Plane * Marking knives, try square, etc.

I'm planning to buy power tools as I need them, probably starting with a Tormek sharpening system as I'm tired of using sandpaper to sharpen my chisels. I'm trying to figure out what to buy first, TS or router & router table. Since the TS tends to scare the sawdust out of me, I'm leaning towards the router. Having said that, Woodcraft just started carrying a General International Tablesaw with a left-tilting blade which looks _sweet_.

Cheers, Scott

[bridger]

and it's in... section 7- finger joints.

it's not a joint that I can see much use for beyond practice with the tools type stuff. if I'm looking for quick-and-dirty I'll assemble butt joints with staples and glue. if I want strong I'll choose a joint for the application- but I doubt that that joint would turn out to be the method of choice anywhere. If I want attractive I doubt it will be on the short list either, but that being an aesthetic matter someone else might have a different take.

[bridger]

given that, I'd say use the dozuki and the chisels

since you are doing this for practise, get some extra wood and try it a few different ways. for instance, you can use the miter saw to do the crosscut part. it's not the best possible way to do it, and you will likely have to finish off the cut with a chisel, but you will learn something and gain some skill with your saw in the process.

get the table saw first. use it to build the router table. keep the router table simple and figure on replacing it within a year as you figure out what features you actually need. put the money you save into a better quality router.

don't make the mistake of thinking that the router can't or won't bite you. router injuries are nasty.....

it doesn't seem to be on their website yet.

shop around a bit- and if you want to read a bit more, choosing a tablesaw is a subject that regularly gets beaten to death here:

recommend that you buy an older american made table saw.

[J. Clarke]

For the cut you're doing Dozuki and chisels would be the way to go unless you want to go for the table saw.

Table saw or radial arm saw would be your first purchase IMO. Table saw is the ripmaster, radial arm is the crosscut master. Both have their strengths and weaknesses, either will do most of your straight cuts. Since you already have a compound miter saw I'd go with the table saw.

Rather than the Tormek, consider getting a couple of 8" diamond plates ranging from xtra course to extra fine and a black Arkansas or a polishing waterstone. Even if you get the Tormek later you won't regret having them. I can generally get from "beat up" to "surgically sharp" faster on those than I can using a grinder. Several times in my life I considered a powered sharpener and asked myself why, and the answer invariable was "fast stock removal on a really beat up tool" or "fast stock removal to change the cutting angle", and every time I added a coarser stone to my collection until finally I had one course enough.

[patriarch]

[e-mail] wrote in news: [e-mail]:

Scott,

Bridger has offered good advice, in all respects.

I add only this: Post a digital picture when you get the first box done. Then do one with contrasting woods, just for showing off.

And feel free to come back here for help, whenever.

Patriarch

[philly45]

I would get the TS first....