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Discussion Starter · #1 ·
Hey everyone,

I am building some nightstands for my wife and I want to try to use dowels. I have a good self centering jig and I have used successfully used them in the past for face frame construction and alignment help but I have never tried them for putting together a cabinet/carcuss.

I will be using 3/4" Baltic Birch Plywood with 3/8" dowels. I am worried about the face to end grain connections being strong/rigid enough.

Any recommendations for dowel spacing/embedment into the face of the 3/4" ply? I have 1-1/2" long dowel pins and I was going to try to embed them at least 3/8".

Any help is much appreciated!
 

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They would work fine drill in a dowel ever 6-8 inches and it would be a solid joint
 

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Hello cpb213,

I feel kind of foolish sharing this...but here goes.

Will the method as described work...Yes.

It being a sound and solid connection...??...that is a perspective of what we call strong enough and compared to what?

In testing of such joints, doweled joints are the least solid compared to actual mortise and tenon. Nevertheless, if your needs are not for the strongest and most solid joint, but one that will work under the service load you intend for it...The plan as described is as good as several other and maybe only slightly weaker than Biscuits.

Hope that helps.
 

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".The plan as described is as good as several other and maybe only slightly weaker than Biscuits."

How could a dowel joint be weaker than a biscuit joint?

George
 

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Hello George C.,

With a penetration depth of only 3/8" there are biscuiting types/form and methods that would be considerably stronger than this size and depth dowel. When enough biscuit of the better quality and used in concert form will yield a much stronger joint as it is moving closer to a true Mortise and Tenon or Spline/Toggle joint.

I would agree (even in testing) the lesser forms of "biscuit work" are about the same as many Doweled systems. This is not my point of reference here however.

I moved away from Dowel Joinery decades ago because of just how weak they are compared to faster and stronger methods. The only time now Dowels are employed is in period traditional work of certain types, yet these are much larger and go in much deeper...

Free Toggles (what some call Domino now) are by fare superior to this method.

Yet to the OPs question...if he finds his method strong enough for his needs...then he should be satisfied with that.

I see no egregious fault in his description of work (per se) other than it isn't nearly as strong as it could be with more traditional joinery methods.

Hope that helps clear things up...
 

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Hello cpb213,

I feel kind of foolish sharing this...but here goes.

Will the method as described work...Yes.

It being a sound and solid connection...??...that is a perspective of what we call strong enough and compared to what?

In testing of such joints, doweled joints are the least solid compared to actual mortise and tenon. Nevertheless, if your needs are not for the strongest and most solid joint, but one that will work under the service load you intend for it...The plan as described is as good as several other and maybe only slightly weaker than Biscuits.

Hope that helps.
Uh, I think the numbers would disagree with you on this one:
https://woodgears.ca/joint_strength/dowel.html

You'll notice in the testing that while the m&t joint is stronger, the difference is about 15 pounds of force between the two. The idea that a biscuit joint would offer more strength than a dowel joint is a bit of a stretch, the difference in glue surface, strength of the parts to be joined and even grain direction all give the dowel the edge.

I also find it odd that you'd consider dominos to be a superior method, strength wise, given that all a domino is is an ovate dowel that costs more
 

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Really with plywood there is no end grain. There will always be some of the wood running parallel with the joint. Doweling is an acceptable method of construction as well as many others. Personally I would prefer to miter the joint and run a spline in it.
 

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This is from a production shop that meets AWI standards for premium work. Most of our work is done with either particle board or MDF cores @ 3/4" thick. Because of our equipment dowel spacing/gluing is very precise. All dowel holes in the face are drilled while the parts are being cut along with all other detailing on a CNC router. Accuracy better than I can measure. Parts then go through the automatic edge bander and then to the bore & insert machine. It auto sets up via a bar code that references the CAD/CAM information on the server. It isn't as accurate as the router but OK for most things with a max error of .002". It drills the edge, blows the dust out, injects glue, drives a dowel to the prescribed stick out, moves to the next hole and does it again. Elapse time, 1.2 seconds per dowel. Dowels are 8mm x 35mm fluted, auto fed from a vibratory hopper. The machine is normally setup so that two parts can be loaded, opposite ends. If small parts are being run the operator can put a center stop in so 4 parts can be in position at once. Trouble is he can't keep up with the machine that way. Next stop is the assembly table where the hardware is put in (drawer guides, hinge plates etc.) a measured amount of glue is injected into each face hole and the case is loosely knocked together and slid into the case clamp. Push green button. Top & side pressure beams move into position so they simultaneously press the case. Operator starts assembling the next case, knocks it together and pushes the finished case through the clamp. The clamp has automatically opened at a preset time, about 2.5 minutes. Clamping times and pressures are adjustable via the PLC control.
Now about a dowel joint being "weak". Once in awhile a design error is made and something isn't right on a finished case. TEST TIME! We get to destroy the case by any means employees can dream up. The dowels have never failed! What happens is that big chunks of the case sides are torn out around each dowel.
We have Lamello biscuit joiners that work fine but are slower. We have the Domino system works much like the Lamello machine and is used for odd connections in solid lumber. We have the Hofmann dovetail key machine that is used for mitered joints, mostly. We also have a Maka oscillating chisel mortising machine for solid lumber connections.
The most used system: Dowels. Why? Fast, meets architectural specifications, and is more than strong enough. There are times when none of these work as well as using Confirmat screws.
About doweling the plywood. Baltic birch is thicknessed in metric units Your "3/4" is probably 18mm. Make your dowels go as deep as you can, why stop @ 3/8"? Use care to not get too much glue in the holes or you will hydraulically pop the face out! Have all your clamping setup before starting to glue. Check square and adjust clamps. You can get good accuracy by making stop blocks to set the doweling jig against so all holes are the same spacing on each part.
 

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Hello Epicfail48,

I don't think it's worth posting a bunch of "dueling tests" of what is stronger. In the long run (and in more academic based studies) a traditional M&T joint is going to always be considerably stronger than the average application of dowel joinery.

Can dowels be arranged in concert patterns to test higher or even beat a M&T joint...of course they can. Nevertheless, that is not a simpler or faster joint to cut by any stretch of imagination, nor within the scope of what is being tested, nor perhaps what the OP asked.

Even well executed Draw Born M&T (no glue) will exceed the strength of most (average) doweled joints of comparable wood species and member sizes. It really isn't a debate, but illustrated in countless academic studies over the decades in most Material Science department of colleges that study wood.

We will have to...agree to disagree... about traditional Toggles (aka free tenon) being anything at all like a dowel. Mechanically the are nothing at all like a dowel by any stretch of physics or wood joint mechanical application. Independent testing (not just by Festool) bares that out before the Domino Jointer even existed as Toggle joinery in several forms have been around for well over 2000 years or more. When these are used in concert with one another they exceed anything a dowel could ever approach in achieved strength. Toggles have held the Decks, Bulkhead, and Sides of Ancient Sailing vessels together that see centuries in pelagic crossing all over the world and in several seafaring cultures. They are also found in some of the largest and oldest wooden structures in the world...In neither of these places will you find dowels employed in such a fashion...Dowels are relegated to very light and transient work at best when examined from a historical perspective...

Dowel Joiner grew out of the IR (Industrial Revolution) to expedite and build mass produced wood items...not to build enduring or well made ones in there overall (average) application of use.
 

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The most used system: Dowels. Why? Fast, meets architectural specifications, and is more than strong enough.
Couldn't (and wouldn't) debate your post at all Larry S....It is a perspective of craft and style of workmanship.

And as I stated to the OP...if it is good enough for his needs...great!. Overall, as he plans to use the dowels it seems his method should meet his needs...

I can reflect that I know of many shops now that have removed all their dowling equipment completely from use in favor of Toggle Joinery systems of various forms. I would also note that not one of these I know ever have (including me) ever work with Particle Boards of any kind and seldom use plywood. For Those shops that do, I imagine that dowels would be more than materially strong enough to meet the structural demands of those given materials and applications.
 

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Discussion Starter · #11 ·
Thanks everyone! Great discussion on dowels. I haven't been woodworking very long (less than a year) so I am still experimenting with different joinery which is why I would like to use dowels for this project. Even though pocket holes are quick and easy, I hate the idea of filling the holes...

I have always read about tests showing how strong dowels can be but all the tests I've seen involved the dowels being embedded 3/4 to 1" in each connecting piece compared to the 3/8" I was proposing.

I'll go deeper than 3/8". Ill just have to set up a good stop collar so I don't blow through the other face of the piece.
 

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This is from a production shop that meets AWI standards for premium work. Most of our work is done with either particle board or MDF cores @ 3/4" thick. Because of our equipment dowel spacing/gluing is very precise. All dowel holes in the face are drilled while the parts are being cut along with all other detailing on a CNC router. Accuracy better than I can measure. Parts then go through the automatic edge bander and then to the bore & insert machine. It auto sets up via a bar code that references the CAD/CAM information on the server. It isn't as accurate as the router but OK for most things with a max error of .002". It drills the edge, blows the dust out, injects glue, drives a dowel to the prescribed stick out, moves to the next hole and does it again. Elapse time, 1.2 seconds per dowel. Dowels are 8mm x 35mm fluted, auto fed from a vibratory hopper. The machine is normally setup so that two parts can be loaded, opposite ends. If small parts are being run the operator can put a center stop in so 4 parts can be in position at once. Trouble is he can't keep up with the machine that way. Next stop is the assembly table where the hardware is put in (drawer guides, hinge plates etc.) a measured amount of glue is injected into each face hole and the case is loosely knocked together and slid into the case clamp. Push green button. Top & side pressure beams move into position so they simultaneously press the case. Operator starts assembling the next case, knocks it together and pushes the finished case through the clamp. The clamp has automatically opened at a preset time, about 2.5 minutes. Clamping times and pressures are adjustable via the PLC control.
Now about a dowel joint being "weak". Once in awhile a design error is made and something isn't right on a finished case. TEST TIME! We get to destroy the case by any means employees can dream up. The dowels have never failed! What happens is that big chunks of the case sides are torn out around each dowel.
We have Lamello biscuit joiners that work fine but are slower. We have the Domino system works much like the Lamello machine and is used for odd connections in solid lumber. We have the Hofmann dovetail key machine that is used for mitered joints, mostly. We also have a Maka oscillating chisel mortising machine for solid lumber connections.
The most used system: Dowels. Why? Fast, meets architectural specifications, and is more than strong enough. There are times when none of these work as well as using Confirmat screws.
About doweling the plywood. Baltic birch is thicknessed in metric units Your "3/4" is probably 18mm. Make your dowels go as deep as you can, why stop @ 3/8"? Use care to not get too much glue in the holes or you will hydraulically pop the face out! Have all your clamping setup before starting to glue. Check square and adjust clamps. You can get good accuracy by making stop blocks to set the doweling jig against so all holes are the same spacing on each part.
WOW! I am not about to try to read that mass of words. Paragraphs were invented for a reason.

George
 

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Hello Epicfail48,

I don't think it's worth posting a bunch of "dueling tests" of what is stronger. In the long run (and in more academic based studies) a traditional M&T joint is going to always be considerably stronger than the average application of dowel joinery.

Can dowels be arranged in concert patterns to test higher or even beat a M&T joint...of course they can. Nevertheless, that is not a simpler or faster joint to cut by any stretch of imagination, nor within the scope of what is being tested, nor perhaps what the OP asked.

Even well executed Draw Born M&T (no glue) will exceed the strength of most (average) doweled joints of comparable wood species and member sizes. It really isn't a debate, but illustrated in countless academic studies over the decades in most Material Science department of colleges that study wood.

We will have to...agree to disagree... about traditional Toggles (aka free tenon) being anything at all like a dowel. Mechanically the are nothing at all like a dowel by any stretch of physics or wood joint mechanical application. Independent testing (not just by Festool) bares that out before the Domino Jointer even existed as Toggle joinery in several forms have been around for well over 2000 years or more. When these are used in concert with one another they exceed anything a dowel could ever approach in achieved strength. Toggles have held the Decks, Bulkhead, and Sides of Ancient Sailing vessels together that see centuries in pelagic crossing all over the world and in several seafaring cultures. They are also found in some of the largest and oldest wooden structures in the world...In neither of these places will you find dowels employed in such a fashion...Dowels are relegated to very light and transient work at best when examined from a historical perspective...

Dowel Joiner grew out of the IR (Industrial Revolution) to expedite and build mass produced wood items...not to build enduring or well made ones in there overall (average) application of use.
So, despite the fact that I posted a strength test with pretty well researched numbers showing that a dowel and m&t joint are very comparable in terms of strength, I'm wrong based on the results of a test you don't feel the need to share? That seems a little insulting mate. I'd also like to point out that nowhere did I say that a dowel joint was stronger, I said the exact opposite in fact, that a m&t join is stronger than a dowel joint. My argument was that a dowel joint isnt anywhere near as weak a joint as you implied.


This is a domino or loose tenon joint

This is a dowel

I'd love to know how the fact that a domino is ovate makes it completely different. Even a traditional rectangular loose tenon is the same concept, a piece of wood shaped to fit a pocket in both pieces. The only difference between the three is total glue area, the domino will have slightly more than the dowel, the traditional style can have more or less depending on the size.

I've got no problem with being wrong, but the condescending attitude is a little irritating. If you disagree with me, don't tell me I'm wrong and I need to get over it, present your facts the same as I did
 

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Hello Epicfail48,

One of the huge challenges in posting on forums (not eye to eye conversation) is the inevitable tone that can inadvertently be given...So, with that, let me humbly apologize if you felt for a second I was being condescending to you. Challenging yes, no doubt and assuredly sharing a different view of things, but If this was over Coffee (or a beverage of your choice) we would just be "hashing" at different points but I believe both would enjoy the debate...Again, sorry if I cam accross poorly, I am always working hard on my writing skills dependant on venue.

Back to the topic of you points raised...and I'll try not to be so long winded (or penned...ha, ha.)

So, despite the fact that I posted a strength test with pretty well researched numbers showing that a dowel and m&t joint are very comparable in terms of strength, I'm wrong based on the results of a test you don't feel the need to share?
You're not wrong at all Sir...not one bit...this isn't a..."right or wrong"...topic. It is a comparable range of views and can only be specified based on equal comparables. Finding studies is relatively easy and no need to bog down the post to illustrate them. Fine Woodworking (and other Taunton Press publications) have them as does many Collegiate Journals...feel free to seek the out and form additional perspectives on the topic if you care to. In most M&T are always structurally stronger.

As stated before in the quote...dowel joints can be made even stronger that M&T joints...yet, when speaking of averages they are not. They are often faster to cut in many application...even in the historic context. Nevertheless, the Toggle will still when out when superior strength is required or wanted...especially if the penetration depth is shallow...like 3/8". Toggles can then act like a spline if used in concert, offering much larger gluing surface...

My argument was that a dowel joint isnt anywhere near as weak a joint as you implied.
Again, apologies...I don't want (nor care to) argue with anyone. If this is your view, I support you to have it. Dowels...on average...is going to be markedly weaker that the same comparable numbers of systems that employ a Toggle system. That average meaning all methods and applications from Walmart Crap furniture construction to historic well laid out and applied Dowels...That's my perspective and interpretation from my observation of work seen and done by my own hands and the understanding of many collegues as well. Of course there are those that construe this topic differently, which is just fine...;)


I'd love to know how the fact that a domino is ovate makes it completely different. Even a traditional rectangular loose tenon is the same concept, a piece of wood shaped to fit a pocket in both pieces.
They are not the same concept at all and only share similarities in application within a negative opening in the receiving member (aka mortise or drilled hole.) The largest and most critical mechanical weakness of a dowel...when compared structurally...to a Toggle, whether it has ovate edges or not...is the quantifiable surface area difference between Toggle and Dowel. Dowels geometrically are nothing but ovate edging over their entire surface other than the two end grain section...and that is the largest difference between them comparably...and the reason the are not structurally as strong as most Toggle system...

The only difference between the three is total glue area, the domino will have slightly more than the dowel, the traditional style can have more or less depending on the size.
Exactly...yet there is not a "slightly more," difference. it is considerable when actually looking at the physical mechanics from an engineering perspective of stiffness and overall strength. This too is quantifiable with some rather heading mathematics that I can barely follow when having discussion with my own PE on projects...Nevertheless, that added surface area, even though it may appear negatable is enough to make an exponential leap in strength.

So in a nutshell...I never said you are "wrong" and wish you peace. I just think perhaps we have different perspectives and probably experiences with these jointing systems...

Regards,

j
 

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Something seems to have been missed about the original post. It was about panel construction. I'm not familiar with a mortise & tenon panel construction. Perhaps you are talking about dado construction?

The original post was about using 3/4" Baltic birch (probably 18mm since BB is metric)
BB is nice, usually, it doesn't suffer from quite as much deviation in thickness as domestic plywood but is prone to just as much instability resulting in twists and turns that are not acceptable in a manufacturing environment.

The particle core and MDF core you can buy @ retail are usually not the industrial grades. Big difference. Even within the industrial grades there are significant variations. My shop only processes about 40 to 60 sheets per day, mostly melamine coated particle core. The core is western board with a fine face. The Melamine paper is a medium wt..

Cheap melamine finished furniture is made with the cheapest possible materials because the people buy on price so that's what they are sold.
 

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Something seems to have been missed about the original post. It was about panel construction. I'm not familiar with a mortise & tenon panel construction. Perhaps you are talking about dado construction?

The original post was about using 3/4" Baltic birch (probably 18mm since BB is metric)
BB is nice, usually, it doesn't suffer from quite as much deviation in thickness as domestic plywood but is prone to just as much instability resulting in twists and turns that are not acceptable in a manufacturing environment.

The particle core and MDF core you can buy @ retail are usually not the industrial grades. Big difference. Even within the industrial grades there are significant variations. My shop only processes about 40 to 60 sheets per day, mostly melamine coated particle core. The core is western board with a fine face. The Melamine paper is a medium wt..

Cheap melamine finished furniture is made with the cheapest possible materials because the people buy on price so that's what they are sold.

Sometimes melamine is desired in interiors of high end pieces. Wood isn't always the winner....

Sorry I'm late for the party. I used dowels a few decades ago and still do. M&T,Double M&T,dowels,Domino's,Biscuits,etc. Can I play?>:)
 

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Sometimes melamine is desired in interiors of high end pieces. Wood isn't always the winner....
Not to side track too far of the OP's query, but can we agree this is a perspective?

Wood is wood, and usually means a s solid naturally occurring substance...

Melamine is no more a piece of wood than is any other chunk of made made plastic or related solid material. I know that very high end, expertly designed and built modern pieces can be made from higher quality Melamines, so I don't suggest this can't be done...but...it is not wood nor really comparable to it. Melamine is not in the category of wooden furniture, no more so than some of the modern metal and other plastics or composite materials...

Just an alternative view perhaps...but wood is always the winner when discussing wood...Melamine is in a category of its own...
 

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I understand your are making appoint about solid wood being "wood." Does that mean the original post about using plywood is or isn't wood?
Solid wood is not always the best material for the job at hand.
 

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Not to side track too far of the OP's query, but can we agree this is a perspective?

Wood is wood, and usually means a s solid naturally occurring substance...

Melamine is no more a piece of wood than is any other chunk of made made plastic or related solid material. I know that very high end, expertly designed and built modern pieces can be made from higher quality Melamines, so I don't suggest this can't be done...but...it is not wood nor really comparable to it. Melamine is not in the category of wooden furniture, no more so than some of the modern metal and other plastics or composite materials...

Just an alternative view perhaps...but wood is always the winner when discussing wood...Melamine is in a category of its own...
A piece of furniture may be many things. Plastic. metal, glass,wood,etc.
 
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