Doweling question

Re: Doweling question

Pete in Holland MI

Dowelling requires accurate layout, and accurate drilling, for everything to line up well.

Ever since I bought a bisket cutter 15 years ago, I don't think I've used a dowel since. They allow some variation of the location on the joint, and are easily machined with several hand held cutters. Some question the strength of a bisket joint, but I've not had issue with them.

Long grain gluing

Dick Coers

You have a lot more long grain gluing area with a tenon compared to 2 dowels if we are talking about door construction. Also more long grain in case construction than with multiple dowels. But alignment drove me away from dowels when Elu came out with a more affordable biscuit machine than the Lamella. Funny story about me and Elu. I failed to maintain my first machine and let the bevel gear get too dry and it wore out the gears. I replaced it with a new machine instead of buying parts since I was in business. Not long latter, Elu was purchased by Dewalt and they discontinued the Elu design. I bought a back up, and it's sat unused in the original steel box. Think a 35(?) year old NOS biscuit joiner is a real collectors item?

Re: Doweling question

John Foster

I think that options have increased, but doweling will never die out. I am sure our grandchildren will still do some dowel joints. I have 3 manual dowel jigs that I use to varying degrees. Sometimes when you are attaching odd shaped, broken or other pieces that resist clamping and accurate measuring nothing can replace the good old dowel points.

My biscuit joiner collects dust most of the time other than when I am doing face frames.

We tried out a Festool Domino; my wife found it awkward and too heavy.

One of my mid life crisis purchases is a Felder slot mortiser, with the dowel spacing bars, I probably use it just as much for doweling as slot mortising.

Speaking only for myself, I am always keen for the "next best thing", but Grampa's way of doing things never goes away,

Alignment

Jerry Gibbs

I understand the alignment issue. Why is alignment a issue with dowels and not with loose tenons or dominos. I ask because drilling a hole is cheap and easy. Would slightly undersized dowels solve the problem?

Re: Alignment

John Foster

I think that I would stick to matched dowel and hole sizes, I would probably try to do my order of operations such that at least one of trimming, planing, sanding could follow the doweling to correct inaccuracies.

Re: Alignment

Dick Coers

I don’t fit my floating tenons tightly side to side. With all the glue area I’ve never had trouble.

Detailed answer

Bill Tindall, E.Tn.

Summary: It is rare to find a failed mortise and tenon joint. It is common to find a failed dowel joint.

I began woodworking with dowels for all the reasons you have discovered, summarized as easy and cheap. Over time time they all failed. I threw out a table a few years ago with doweled legs that failed. A desk with failed doweled legs is on the way out having been replaced by one built with mortise and tenon. Many chairs with doweled joints have been tossed over the years.

There are no cheap and easy ways to make M&T joints. But if you are going to make lasting furniture you need to find some means of achieving this joint. Probably a hollow chisel mortiser is a place to start. It is easy to make the tenon on a table saw by any number of means.

A good rule of thumb is to never use a dowel joint when the goal is a joint that will last for decades. Think about a dowel hole. Only a small fraction of the gluing surface is long grain which makes a strong-as-wood bond. The rest is some fraction of end grain that provides little strength.

Now consider expansion and contraction over time. In a mortise and tenon the two mating pieces move approximately the same over time. In a dowel joint , because of the end grain involved, they don't.

Finally consider the overall glue area of a dowel vs mortise and tenon. The dowel is small.



However, shown is a Krenov style cabinet made with Krenov engineering. The sides are doweled to the top and bottom with a line of dowels, not mortise and tenon. The reason for dowels over M&T is a result of how these parts are fitted (I could explain of there is interest). Strength is provided by a tight fit back glued in place.

Re: Alignment

John b

Pella builds there doors with dowels and calls it a feature . John b.

Thanks

Re: Doweling question

TomD

The problem with dowels is that when they are glued in most 90 degree orientations they are side grain glued to end grain, which is why the dowels fail, relatively early in service life. However in the Krenov cabinet shown by Bill there is very little loading, and a lot of dowels. There would be failure if you had a drawer dowelled where dovetails might be used, or if the dowels were in a door.

Dominos are better than dowels because they have side grain to side grain contact, so they are pretty well glued.

M & T joints fail with regularity, but over long time periods. If they were glued with hide glue, they would be easily reglued. Dowel joints are harder to repair, as the joint fails, something often breaks. I have used milling machines to excavate the dowel, and reglue.

If you need a great deal of strength and have space biscuits and dowels are a good combination in those situations where biscuits can break out laterally the biscuits have a lot of bonding area, but they sometimes need the directional limitations dowels can provide.

The argument that dowels require greater precision than many other methods does not pass the "so easy when you know how" test, which is were industry and people who have been around a while stand.

Dowels have multi-direstional precision and restraints, that even stronger tools like M&Ts do not have. All the biscuits and tenons and slip tenons, and dominos are loose in one direction other than depth of insertion.

When you need real strength, hardware bonded with epoxy is the tool, and it does not require precision.

Often biscuits are strong if they are paired and if one only uses the largest size. I have made frames for cabinet doors that have lasted a few decades of regular use with no sign of weakness by bonding a single biscuits in the largest size in each joint. Though too large to fit, I trim a birdsmouth into one end of the biscuit to accept the panel, and I use pliers to pull the biscuit out the back of the frame so that where the cut blew out to the outside corner of the frame it looks like a tightly fitted spline.

Re: Detailed answer

TomD

"There are no cheap and easy ways to make M&T joints. But if you are going to make lasting furniture you need to find some means of achieving this joint. Probably a hollow chisel mortiser is a place to start. It is easy to make the tenon on a table saw by any number of means."

Agree, basically. There are a ton of tools that will do the work in a set-up in industry. Clients don't think of furniture the way that would be required to make it worthwhile for most uses.

What does catch up on time in my shop is all the other alternatives do not allow through grooves in the frame. The grooves need to be stopped, which is always a hassle. So at least one gets that set-up and time in execution back.

Re: Detailed answer

TomD

"Now consider expansion and contraction over time. In a mortise and tenon the two mating pieces move approximately the same over time."

Not really they are at 90 degrees so they will shear apart over time.

While not probably the issue here, some M&T joints are held together by pressure against the endgrain, fox wedging, or compression of expansion. Glue/wood shear may not be an issue.

"However, shown is a Krenov style cabinet made with Krenov engineering. The sides are doweled to the top and bottom with a line of dowels, not mortise and tenon. The reason for dowels over M&T is a result of how these parts are fitted (I could explain of there is interest). Strength is provided by a tight fit back glued in place."

Krenov backs were solid wood, and floating, not glued. If glued, or not floating, wood movement would have reared it's head, big time. At least as far as I remember. May be time to reread his books. (There are ways of supporting the sides with the back, but I have virtually never seen them used.) Dowels work well in these carcasses simply because the dowels are so numerous. He also differentially spaced them like his dovetails, so there were more of them towards the edges. However, had he had any worry, he could have added even more.

I LOVE Elu!

Derek Cohen (in Perth, Australia)

Dick, I'd make an offer if we did not have different power supplies (we use 240v).

4 Elu routers. The biscuit joiner is Dewalt (aka Elu).

Regards from Perth

Derek

Doweling alternatives

Derek Cohen (in Perth, Australia)

I’m curious why dowels seem to be out of favor. For loose tenons router based mortises are favored. The Festool Domino is a great machine but out of my price range. Clamping on a quality doweling jig and drilling a hole is easier and quicker than using a router. I’m trying to understand the difference between a dowel and a domino and a loose tenon in practice. Jerry

Jerry, as others have noted, dowels are extra fussy about alignment, and this is their undoing. I do not think that it is about the strength factor.

I cannot recall when I last used a dowelled joint, possibly about 3 decades ago.

I suspect that Krenov used them with his cabinets owing to the nature of the construction (essentially butt joinery). He used machinery for roughing out, but otherwise preferred hand tools. Dowels are more hand tool-orientated than biscuits (which he could otherwise have chosen).

Krenov aside, I think of dowels as largely a beginner's method. They are fully jig-driven, and require lay out rather than hand skills. The biscuit joiner was a very popular machine until the Domino came out. It surprises me that so many sold their biscuit joiners at this point - it is a valuable machine and different from a domino in where the strengths and weaknesses lie.

I see the two machines as complementary and not as one replacing the other. The biscuit is long and shallow, which is better for mitres. The domino is long and slim, which makes for a mortice-and-tenon joint.

Both machines offer a little leeway when fitting, which dowels do not, and make perfect alignment possible even when cut slightly out.

While I have both machines, my preference is a true M&T joint, which I cut either by hand, or with the assistance of a bandsaw (tenon) or router (mortice). Making a M&T allows for greater versatility in design for strength. Also for ease in repairing joints. Biscuits and Dominos both lack variation and are much more difficult to repair or pull apart. Dominos, on the other hand, can lend themselves to some clever, off-angle joints, such as in chairs.

Regards from Perth

Derek

Some disagreement

Bill Tindall, E.Tn.

dowels are extra fussy about alignment

In the beginning when I used them I had a quality doweling jig. I do not recall having alignment problems doweling legs to frames, or stiles to rails in framed doors.

I do not think that it is about the strength factor. In my applicaitons it was all about strength. Every doweled leg that failed did so because the dowel broke. I have a desk with doweled broken leg sitting in the hall awaiting to be burned.

I suspect that Krenov used them with his cabinets owing to the nature of the construction (essentially butt joinery). He used machinery for roughing out, but otherwise preferred hand tools. Dowels are more hand tool-orientated than biscuits (which he could otherwise have chosen).

Krenov used them to fasten sides to bottoms as in the case previously illustrated for a reason not obvious till you build one of these cases. If hand tool oriented you would mortise and tenon the side to the top and bottom, exactly what I did when I built the prototype. Disaster! I visited a local Krenov student and learened how. The door for these cases is built first and the case fit to the door. And the door is knife hinged. By the time the door is meticulously fit and the hinges in place the sides will have been on and off countless times. M&T joints destroyed by this time. So......you make a doweling template and use it to drill the line of dowels that will hold sides to top and bottom. Two of the 7 dowels are dry fit in place. When the hinges are finally fit the sacrificial dowels are discarded and new dowels added to all 7 of the holes . PIC shows drilling. There is no problem aligning the 7 holes with the mating parts.

Biscuit jointer for sale

Bill Tindall, E.Tn.

I have a tip top shape machine for sale along with lots of biscuits. email if interested.

Re: Some disagreement

Derek Cohen (in Perth, Australia)

I wrote: dowels are extra fussy about alignment

You wrote: In the beginning when I used them I had a quality doweling jig. I do not recall having alignment problems doweling legs to frames, or stiles to rails in framed doors.

Bill, that is the point - you need a high quality doweling jig, otherwise it all goes to hell. Both biscuits and dominos have leeway built into them. They are less fussy, and still provide accuracy - that is why they are popular.

I am not advocating these machines. I am a traditional joint guy. I have a Domino as I used it to build a kitchen. It was worth it. I have a biscuit machine. It is useful for making spline for mitred joints. (I would not be in a hurry to sell mine, but you know what is best for you .. )

Regards from Perth

Derek

Re: No disagreement

Bill Tindall, E.Tn.

agree on the jig. I went through several before I found one that poked holes reliably. Have not used it in decades. It self centers on thickness making it good for face frames which is where I most used it.

Re: Some disagreement

TomD

We live in a world were a drill press can regularly be found for 20-40 bucks, at every highway exit across my city when I last looked. That gives one all one needs to Krenov some casework. He used a hand fed horizontal boring machine that was part of his saw, a wooden jig, and a hand drill. Meanwhile the Domino, which is a very clever tool, is 1500 bucks.

I struggle with the idea that there is a step down for, say, a kitchen, where a domino is the right tool, but a biscuit would be too downmarket. I think biscuits are fine for that kind of work, though domino is better and possibly faster. But there is some mistaken idea that biscuits are not strong enough.

Kitchens are a tough situation. The most used casework in the house, usually, but they go in and out of style so regularly that they are not deemed worth all the hand work that would underlie a top quality job. I agree with that approach as a reality we may face. I just don't see the biscuits failing on that program. Their failure mode is on materials like those used in cabinet doors, but where the loads are trying to break the endgrain piece away from the sidegrain piece laterally. Imagine one glued and screwed the stile on the hinge side of the door to the cabinet, but tried to open the door anyway. That is not a cabinet door failure mode.

Slip joints are another option where they can easily be machined to high quality, with handsome exposed joinery. They seem to hold up very well.

Re: Some disagreement

Barry Irby

I have wondered why you can't stop the oscillating motion of the Domino so you could use dowels. Perhaps Dominoes are more profitable as a consumable.

It's been done

Jim Matthews

https://www.timberwolftools.com/mafell-ddf40-duo-dowel-system

The advantage of the Domino is in repeatable setup and access to uniform "plugs".

If you're making a few hundred feet of laminated table tops, it might make sense.

For thinner sidewall material, alignment is less secure (without an auxiliary fence).

For the weekend worrier - it's an expensive option.