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What join to use to join four 2X4 wood pieces together for a pedestal as in the picture? Here is what is going on in my mind. Need some help.

  • Just glue them together - would not be strong..

  • Cut a rabbet vertically and slide them in - rabbet along the grain may not be strong as well.

  • Drill 5/8" holes in them and use circular hardwood dowels - current solution in mind - need to know if it is a good idea.

I chose 2X4s because of the thought to join them with circular hardwood dowels.
I can switch to 2X6s as well if someone can suggest a stronger joint.

This would be a pedestal for my Pedestal table(my first wood working project)enter image description here.

Aravindh Sathish
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4 Answers4

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Just glue them together - would not be strong..

Would be strong. I doubt very much you'd be able to break it apart with your hands if you do the joints right.

Drill 5/8" holes in them and use circular hardwood dowels - current solution in mind - need to know if it is a good idea.

Yes that would reinforce the joints hugely. Even with a hammer you wouldn't be able to take the joint apart without breaking the wood.

But there are a couple of better ways of doing this.

The main weakness of the pedestal as shown is the exposed end grain. This is both aesthetically less pleasing and potentially a weakness depending on what the pedestal is for (not really a problem for indoors though). So it's better to use a mitre joint of some kind:

Quadrilinear leg sections

The above image is for what's called a quadrilinear leg (intended to show quarter-sawn figure on all four faces) but obviously the same joints can be spaced apart to produce a post such as you're making.

Unfortunately the best of these, the lock-mitre joint at the right, requires a specialist router bit sized to the thickness of stock you're using.

A plain mitre joint, the option at left, doesn't glue as strongly as we'd like as it's end-grain to end-grain, but it's the simplest to produce by far and reinforced in some way it's strong enough for many applications.

Reinforcing it can be simply a matter of hammering in some nails/brads or spacing a few screws. The screw heads would obviously be very visible so if desired they can be hidden by counter-boring and using wooden plugs, which can become a decorative feature (see previous Answer).

You can achieve much the same look and nearly the same strength by drilling through the mitre and glueing in dowels. In either case, screws or through-dowelled, the mitre joint should be glued up and left to fully cure before doing any drilling.

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Graphus
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As long as you have a smooth glue surface, and the boards are jointed so there aren't any gaps, glue should be plenty strong enough, since you're gluing long grain to long grain in the sketch you included.

Dowels or a rabbet would mainly help with alignment while you're performing the glue-up.

Also, just a note - 2x4s are actually 1.5" x 3.5", unless they are labelled as rough cut, or "true 2x4". You may have to rip/joint an additional 1/8" off of each side and end up with a 1.5" x 3.25" board, both for removing the round-over at the corner, and for ensuring you have a perfectly straight board.

Doresoom
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    Thanks for the response, and the note about round-over corners. – Aravindh Sathish Jun 10 '16 at 17:50
  • Just one quick point, in the original sketch the butt joints are end grain to long grain, not long to long. – Graphus Jun 11 '16 at 06:20
  • @Graphus, I always thought edge grain (not end grain) and face grain were both considered long grain. Is that really incorrect? – Doresoom Jun 11 '16 at 12:50
  • Yes they are :-o Sorry, in the moment I got confused about the orientation of the grain in the boards (I think because I was looking at apron-to-leg joints in small cabinet recently) but here the end grain is of course facing up in all of them. So all the glued joints here are long grain to long grain. Boy do I feel dumb. – Graphus Jun 12 '16 at 06:00
  • Ok, I'm much less confused now. I remember thinking, "well @Graphus said so, so I guess that's right." We all make mistakes! – Doresoom Jun 12 '16 at 13:53
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Welcome to the Woodworking Stack-Exchange!

Just glue them together - would not be strong..

It would be plenty strong. As @Pete mentioned in his answer the glue joint is stronger than the wood it's holding together. That is,

  • If you can apply enough clamp pressure
  • Have smooth surfaces before gluing them together. A jointer, planes or just sanding helps in that regard.
  • The type of wood plays a role as well, though if you only use 2x4s from the hardware store like fir, spruce or something alike you should be good.

As you mentioned that this is your first woodworking project, my guess is, you don't have a jointer or other fancy power tools that would ease up the creation. Hand-planes are not too expensive though and you can achieve satisfactory results with them (and a little patience, practice and perseverance) as well. If those aren't an option either, make sure the surfaces that are glued together are as straight and clean as possible by sanding them.

Cut a rabbet vertically and slide them in - rabbet along the grain may not be strong as well.

I think the rabbet would give the joint even more strength, as well as help you align it and avoid slipping when you glue it up. Gluing long-grain is what you actually want to do as it is considered a strong bond when gluing. For more details on different grains and their strength in glue joints please refer to this question.

Drill 5/8" holes in them and use circular hardwood dowels

If you do this in addition to gluing, that would provide a pretty strong joint that wouldn't come apart any time soon, but in my opinion a severe overkill. Also worth mentioning with this approach is that it can either be optically disturbing, or a really beautiful addition to your piece as the dowels will stand out (in color) quite a bit after you've applied a finish.

Good Sources on the Web

All these points above are valid from 2x4s up to 2x10s or even bigger stock I think. I suggest you watch a video by Steve Ramsey about 'What You Need to Know About Glue | WWMM BASICS'. A great article describing all sorts of stuff that can be done with glue and how strong which bonds are, is from Mathias Wandel (woodgears.ca).

Your approach in general

While having strong bonds and sound joints makes a lot of sense, I think you should ask yourself how strong your joint really needs to be. If I understand your project correctly you're planning on putting something on top of your pedestal, which would only put pressure from the top of the piece. If that is the case, strictly speaking some nails to connect the pieces would suffice as there will be no forces exerted from the sides and the joints don't necessarily need to be that strong. This is of course not beautiful and one wouldn't do something like that for a decorative piece :)

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Stoppal
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    Thanks for the response, I really feel welcomed with such educating responses. I learnt that glueing the right way can actually be stronger than I thought. I will use my sander and some sanding sheet to create a clean smooth surface to glue up. I will go through the article you referred to. – Aravindh Sathish Jun 10 '16 at 17:57
  • Even though I'm not going to use circular dowels with new solution (Mitred joint mentioned by Graphus) I originally thought of using them only on the inner surfaces of all of four pieces. That way it wouldn't show up outside. Nevertheless, as you said, I'd definitely not need such strength for I'm not expecting stress from any other angle. It was more of a beginner enthusiasm to pick only the best of choices for the first project :-) – Aravindh Sathish Jun 10 '16 at 18:02
  • you're very welcome :) good luck with the project. – Stoppal Jun 10 '16 at 18:04
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    I have to take exception to your comment about gluing end-grain. End grain joints are generally the weakest of the joints, even when care is taken to size the end grain. Almost always, too much glue gets sucked up by the grain of the wood, leaving the joint starved for glue. – FreeMan Jun 13 '16 at 18:56
  • Thx @FreeMan for pointing that out! If one cuts a rabbet along the grain it wouldn't be the end-grain but the long-grain that will be glued. I will edit my answer accordingly. Clarification and more details on the issue can be found in Graphus' answer here. – Stoppal Jun 13 '16 at 19:56
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Biscuit jointing would be a good candidate. You'll need a biscuit jointer, some biscuits, and glue.

When using glue, if you have the correct glue on the right surface, the glue joint is stronger than the wood holding it.

PeteCon
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