Tongue n Groove bits

[OFWW]

Please pardon my possible ignorance here.

In researching cabinet jointing methods, thinking along the lines of Joints with no nails or screws, yet still be able to use them if I needed. I ran across Sommerfelds tongue n grove set, which appears to me to just be an adjustable bit set, set for a permanent offset.

It looks like if one were to by two sets of these Rockler adjustable's one could accomplish the same thing for less money, along with long term support. and you have a choice of 3/8 or 1/4" shanks.

Sommerfeld has a third bit included in his set for cleaning up the tongue when necessary so as not to weaken a pocket screw connection. It is a common bit most everyone has.

He mentions how it pretty much inherently keeps the cabinets squared, and it certainly appears to a natural way of doing things and eliminating the craziness of cutting DADO's when the sizes of plywood vary so much. I did notice, however, on his base cabinet explanations that he used a support block for the bottom shelf, at the ends of the cabinet while using the tongue n groove in the FF.

I would appreciate your educated experiential opinions on this. Is the offset Tongue n Groove worth it? Is the T&G as strong as a DADO?

And should a combination of the two be done or just stick with DADO's? (the bottom's of my DADO's always seem to need to be cleaned up so that there is a smooth glue surface)

Freud doesn't appear to have either of these bits, but they do have a T&G set with a centered tongue.

Also a side question regarding router usage. In watching Sommerfelds video's he has a lot of fuzz on his grooves regardless if it is hardwood or plywood. I have had that problem on occasion with wood like poplar, otherwise I have seen very little of that other than the occasional spots on plywood when I make a DADO.

Is fuzz or "hair" to be expected?

[dadiOH]

1. It would be a cold day in hell before I paid 0 for T&G bits
2. Avoid bits with a 3/8" shank unless you already have a 3/8" collet.
3. Why would you want two T&G sets?

1. I don't find all that much variation in plywood thickness; from type to type, yes but no with same speciaes from same source. Regardless, NP if you make dados/grooves narrower than the plywood and cut shoulders on the tongues. The shoulders have the added benefit of positive, visual confirmation of when the tongue is all the way into the dado/groove.

2. I prefer to cut dados/grooves on a table saw with my trusty wobble dado. That means the bottoms are never flat. NP, I always make dados/grooves a smidge deeper than the tongue that is going into them, provides a place for excess glue and also assures that the inserted piece will be at the correct depth (because of the shoulders). If, for some reason I NEED a flat bottom, I use a bottom cleaning router bit (bottom cuts, sides don't; bit sides ride on the sides of the dado/groove) .

1. Whre would you use both a dado and T&G?

2. Fuzz depends partially upon the wood. With any wood, one side of a groove/dado that is cut in one pass with a router bit will always be a climb cut and that side will tend to fuzz. That can be avoided by using a bit that is smaller in diameter than the desired width of the dado/groove and making two passes, one in each direction. That is easily accomplished with two fences set to the desired dado/groove width. It can be accomplished with just one fence if one makes a square router base plate that has its sides at different distances from center. For example, suppose that one side is X" from center; if another side is X+1/8" and you want a 1/2" dado/groove then use a 3/8" bit for the first pass with the "X" side on the fence then turn the router so the x+1/8 side is on the fence for the return pass. No climb cut, No (probably) fuzz.

[OFWW]

I do have one, but the others are 1/4"

Was just thinking of the set up time when switching from tongue to groove. Figured that time saved would also assure that they would match forever once setup for the purposes.

I have seen some differences between old stock and new. When I say old it means it might have been in the shop for a year or so. :)

I had read that if there were gaps, like with a rugged bottom that the joint would be weakened since glue is not to be counted on as a filler. I have always smoother mine with a chisel, like a plane, or a sandpaper rig. I once had an 8ft long dado and wished I have the proper plane for it. Leaning over and stretching to clean it out was not much fun.

Not sure, just was thinking of keeping an open door to it.

DOH! You're right, I just remembered doing just that for the same reasons you described on dado's. T&G would not have that same option. Thanks!

Now as to an offset T&G versus a centered T&G, would you see a reason for it?

[Leon]

Router bits are notorious for not staying keenly sharp for very long. In many instances after 10~20 feet. Basically 2 teeth doing all of the work. Then you deal with the results.

I would advise a good dado set. Really good ones stay sharp for a very long time.

[Swingman]

Took a look the "Cabinet Plans" under the "Woodworking Made Easy" on that website, and was not impressed.

Appears to be a case of the tool (router bit) being the tail that wagged the cabinet making dog.

If a router is the only tool you have maybe, but I make cabinets for a living and were I forced to make cabinets like that I would go broke in a day.

There are much better kitchen cabinet fabrication methodologies than using tongue and groove joinery.

If you're wedded to that style of joining cabinet parts, a biscuit cutter would serve you much better, or perhaps splines in a groove, instead of routing a tonge.

I use routers in much of my work, and one of the givens with routed joinery is an inherent inconsistency in fitting routed parts, amplified by any inconsistency in the dimensions of most purchased project materials.

IOW, it is my experience that for routed joinery to work well you really need to plan on milling ALL your project material to precise dimensions, width and thickness; and even then you will often have inconsistencies in fit between the first of a run of routed parts, compared the last part.

Anyone who has done routed dovetail in dozens of drawers sides for a project will appreciate that phenomenon.

Not that it can't be done, but it takes a good deal of time and effort in milling, tool setup, and a thorough knowledge gained from lots of experience with routers and their foibles ... simple things, like the router bit not always being perfectly concentric with the other parts.

Not trying to discourage you on that line of reasoning, but might to ask questions about alternate ways to get to the same destination.

[dadiOH]

Sometimes, eg if you are making cabinet doors and want greater/lesser area on the rails/stiles edges to show.

[OFWW]

Bingo! That hit the nail on the head for me. Watching him closely and seeing the little things, like having to bang parts together at times and other things made me wonder. Then checking to see the bits for sale elsewhere and finding none made me wonder. You confirmed it for me. I can see a use for it, but then the standard setup should be fine.

Actually, seeing your advice, using the dado, for your cabinets was always in the back of my mind, telling me you were doing it for a reason. The bottoms of my dado's always seemed to me to need clean up, and I can get a plane that would do that just fine. But I gathered from Leon, IIRC, that it really isn't that big of a deal. But I'd like to feel comfortable about the clean up before I commit to it. And actually when thinking about it, a plane might just take too much off it I overworked it, and end up throwing off my dimensions and cause things not to fit right.

Odd, all the video's I watched on people cutting dado's and no one spoke much, if anything about cleaning up the bottom of a dado.

I can understand that.

So when making drawers, should I stick to making just a few at a time, or should I use a locking bit, half lap, or? Although I have some of the tools for making a dovetails, I have virtually no experience in that. I have made other simple box joints but I would like the drawers to be strong

No problem, I was looking for exactly this type of advice. I was attracted to the Glue only method he was basically doing, but then it seemed like you said, like he was developing sales for his bits and some other tools to me.

I also saw some people using splines for things like table tops which made a lot of sense to me, using that or dowels or something to keep the boards in tune with each other instead of tearing apart glue joints over the years.

So I guess the questions I have now are, using dado's how clean should the bottom of the dado be, if it is important. Should the dado be cut

1/3 the thickness of the board it is seating into. And if it is wisest to pin the joints after gluing before one removes the clamps.

Regarding FF's I do have the Kreg pocket kit and have learned how to use it, but I am not adverse to joining it another way, like dowels or M&T or biscuits. I don't have the new setup by that expensive tool company, and I would probably be dead before I would even get a decent ROI on any of their tools. IYKWIM. :)

Thanks, and feel free to snip most of this post.

[Swingman]

As long as the depth of the dado/groove is consistent from one end to the other, whether the bottom is pretty or not is irrelevant.

With a good dado stack, and a good table saw to mount it on (no worn or uneven arbor and/or no runout) that is not usually a problem.

What kind of Dado stack do you have? Good place to spend your money When you consider the cost of a good tool with regard to the overall cost of the project ... and the time, effort and waste inherent with an inferior one.

Even with good equipment/tools, probably the biggest problem you'll face with dadoes in cabinet parts is the above mentioned inconsistent depth, usually the result of bowed material when insufficient, downward pressure is exerted as the material passes over the blade.

That is something we alwaysy check after each pass, regardless.

Depends upon your budget. A dovetail drawer will give both strength and appearance.

If appearance is secondary, then a locking rabbet joint, which can be done on the table saw or router, makes a nice looking drawer, with sufficient strength for most any kitchen application.

Again, your overriding concern is a consistent depth of the dado/groove throughout it length.

If you don't have that because of the tool, then you need a better tool.

Search around on some of the New Yankee Workshop videos. Norm had a few shows where he built his FF cabinetry using biscuits. Take a look and see if something like that might fit your budget and tools.

[Swingman]

That'll work and is a good guide. For cabinetry in kitchens and baths I generally do 1/4" deep dado/groove in 3/4 stock.

On occasion, mostly for fixed shelving, especially an intermediate shelf that adds structural rigidity to the casework, I might go to 3/8" deep dado/groove.

With kitchen and bath cabinets, where there will be sheer force applied to wall cabinet components; and with unknown future loads on the base cabinets (including heavy stone countertops); and where you're generally attaching hardwood to a plywood case; or plywood end panels to plywood floors; I'm of BOTH glue and carefully applied nailgun persuasion.

It is rare that I don't both glue and finish nail (16ga/1 1/2") kitchen cabinet components joined with dadoes/grooves ... the face frames to cabinet box; and the end panels to the floors ... therein lies all that blue tape you see to help keep the nail hole filler from bleeding over. Properly done, with the right filler, the nail holes basically disappear after finishing.

Literally hundreds of stained cabinetry and I have never once had anyone mention ever seeing a nail hole in a stained face frame.

Take the time to orient the nail head to the grain direction, and use a filler that will take stain well from experience.

Whether you use both glue, and some other type faster in conjunction with the glue, depends upon the intended use of the piece.

Furniture, where it's hardwood to hardwood, and there is not going to be heavy weight/extraordinary sheer force applied, I almost always just use glue by itself.

Lots of dadoed joinery here in this project, with both plywood and hardwood as primary material, and no nails on the visible casework and "face frame":

(I also included that link above because you mentioned in a previous post about making angled cabinets)

[Leon]

If I may offer something to watch for when cutting grooves/dado's. Especially with longer stock but just as important with any stock inspect your groves/dado's to insure that you cut full depth the entire length of the cut. Often the wood can lift and you will not get a full depth cut. Running the pieces through a time or two again typically insures a consistent depth though the entire cut.

I cut these type joints/groves/dado's all the time and almost always encounter shallow passes. So that is how I know this. ;~)

Also just as important is to use stock that is as flat as possible and the use of feather boards to insure that the stock remains flat against the fence through out the cut is advised.

[Swingman]

Damn! I knew I should have mentioned that five times, instead of just four!

Asshole! LOL

[Leon]

I was just skimming and did not notice if you had preciously mentioned it. I was pretty much restating what you just said but felt a second voice adding emphasis on the procedure might stick better. ;~)

[Swingman]

iceholes, and never question the scorekeeper. :)

[OFWW]

It did and it does add reinforcement. :) Thanks!

[Swingman]

Encourage the cunning scorekeeper at your peril. ;)

[OFWW]

I have two, one 7" that came with the TC and an 8" I bought with my radial arm saw Many, many moons ago. Like, '73 or so. The 8" hasn't been used but once, the 7" I have used 10 or so times, well maybe more. It cut pretty clean on a melamine mdf. plywood, and pine n stuff at the edges, but the bottom was not too hot.

I went out and looked closely, didn't count the teeth but it was a bunch. Sad thing is I just recognized that neither of these was carbide tipped. I have 1/16 th in adjustments on them, and I bought some new spacers because the last project with "3/4" plywood couldn't be matched with the spacers I had.

I checked Rockler on some tests done in 2010, and the pictures they showed looked pretty smooth. Any particular brand you would recommend? or anything to look for in a new set, like 1/32 " adj, more teeth the merrier, etc.? BTW my chippers only have one tooth each end. But wide for overlay.

Oh, my saw is a Craftsman Contract Saw. It was new/older when I bought it and I had to aligned everything on it. It has a great fence, and webbed cast wings so I can drop my tape's and pencils through the grates. It runs true, no slop.

I understand, First time I saw that I wished my Radial Arm saw was not buried in stuff, so I could cut and see the dado's working.

Both are important to me, I have the dovetail kit so I might as well practice and learn. If I bite off more than I can chew I will try the locking rabit.

I have seen where he mounted the FF to the cabinets with a very long groove and biscuits where he felt necessary. I don't remember how he actually joined the ff itself.

Any preferred method as to making the FF first and then the cabinet, or the cabinet 1st or does it even matter?

I appreciate your time spent on this.

While it is raining cats n dogs, and the surf is supposed to be rolling in at 18' or better by Friday, I am at least going to get some wood and do a few practice runs on scraps.

[OFWW]

I like that idea, and freedom to do it.

Then I will follow suit.

Just ran out to the garage, everything I have is 18 GA, so I added that to my list, with blue tape.

Yes, and thanks for the picts and layout.

Great Job! BTW, your doors are perfectly centered, a mark of a true craftsman, per everything I have seen and read. Looked great overall as well. I liked the way you made the face of the cabinet, but I think I will be using a 3/8" inset door, I think they call it.

Last question for now. Is sanded grade 3/4 7 layer project grade plywood good enough for painted cabinets or should I use Baltic plywood for the casings?

[Leon]

Like the Lone Ranger says I am the Lone Ranger,

I am the Score Keeper. LOL

[-MIKE-]

What!? Oh, I heard asshole and it caught my attention. :-D

Anyway, I haven't followed the whole thread but I'll throw my hat in for the table saw as far as T&G joinery is concerned.

I have a few different high quality T&G router bits that I used before a got a good table saw and a stacked dado set. The bit did a fine job but the horse power of my saw and teeth-per-inch of the blades make cutting T&Gs on the saw like a dump truck vs a wheel barrow compared to the router.

[Swingman]

Without seeing the actual stack first it is hard to say definitively, but I would think that most of the time that it would be more than adequate.

Keep in mind that it most often pays to buy ALL the plywood for the project at one time, and from the same stack.

While not absolutely guaranteeing that all panels will be the same thickness, it increases the odds that will be so ... difference in thickness between plywood panels in the same project can play havoc with your final measurements and squareness of individual components.

If you can't do that, and you're using dadoe/grooves for your cabinets, and after you get dado stack setup to your satisfaction, plow that particular setup groove into a short piece of project stock and take it with you, as a check, when you're buying more plywood to insure that your project dado setup and the new plywood will work.