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I've always considered M&T and dowels (done right with the proper jig) a toss-up in terms of strength. I like both depending more on my mood than the project itself.
 

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First time ive seen someone try to use the resistance to twisting of a single dowel as a mark against it. In fairness, it would be a valid criticism, if anybody ever used a single dowel as a joint for anything more than a chair spindle... As is, its a completely useless critique, given that a dowel joint will have 2 dowels at minimum. Breaking a properly done dowel joint will result in the same failure modes as a properly done mortise and tenon joint, i.e the wood around the joint splits and fails. Once that happens, youre talking about bare pounds of force difference, when the joint is capable of handling hundreds either way.

Got numbers to back that up too: Dowel vs. mortise and tenon revisited. For anybody too lazy to read a chart, the average force required to break a dowel joint was 123 pounds, applied a foot away from the joint for plenty of leverage. The mortise and tenon joints failed at an average of 138 pounds.
I don't use them for everything obviously, but chair rails, etc. I'll typically use 2-3..usually the back rails that fail with dowels or M&T especially if you have someone who likes to rock back and forth which is something I never quite understood why my mother got so mad at me for doing until I had to threaten to beat my own kids for doing it.. lol
 
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For quantity uses, I use bags of pre-made dowels with flutes cut in them.
I've yet to find precut fluted dowels that I like. I had a bag of spiral cut I liked, but I can't remember where I got them.. There is an online place that sells them, but you gotta get like a minimum of 1000 or some outrageous order over a few hundred bucks..
 

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Termite
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I've always considered M&T and dowels (done right with the proper jig) a toss-up in terms of strength. I like both depending more on my mood than the project itself.
M&T, dowels, domino's, dowels or pocket screws all have there place but don't confuse strengths or when I should or can use one or the other..
 

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M&T, dowels, domino's, dowels or pocket screws all have there place but don't confuse strengths or when I should or can use one or the other..
That is exactly the type of question that someone without your vast professional experience would want to know ... when to use which type of joinery or which is stronger? What's your opinion on each?

I agree that each type has it's advantages, however.
I have restored some antique chairs from around 1920, that used 2 dowels in all the joints. I took them completely apart, and drilled the old ones out and replaced them with new.
I built a Mission Style quilt rack that has 30 or so mortise and tenon joints.
I used biscuits on a glue up for a buddy's kitchen table top, with good results even though they were not my first choice.
I used dowels to join a microwave stand I made about 40 years ago for my Dad, and its still strong even without a back panel to resist racking.

My theory in the use of dowels in furniture is that they are more of an expedient production line means of fastening than mortise and tenons would be, unless it was a very high volume piece where the tooling would make that means pay off.
I find biscuits easier and faster to use on 3/4" thick stock than dowels. A spline would be stronger only IF the grain is run at right angles to the slot. That would means a whole lot of cross grain thin strips, not as easy to make, but doable.
I used a bench top mortister for some of my quilt rack joints. Then being somewhat frustrated, I switched to a router in a self center jig which was 10X easier and faster, but left rounded corners.
 
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it was't the "strength" of the dowels which made it explode, it was the selection of the tool to cut it. being round, it is tough to hold dowels as the cutter action is moved into the wood. so the more benign the tool the better: hand saw, scroll saw, bandsaw.
 

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it was't the "strength" of the dowels which made it explode, it was the selection of the tool to cut it. being round, it is tough to hold dowels as the cutter action is moved into the wood. so the more benign the tool the better: hand saw, scroll saw, bandsaw.
I totally agree which is why I use a shoe mounding cutter for small pieces instead of trying to use a power saw. It鈥檚 impossible to keep something that small from moving just from vibrations of the saw and movement= binding. Just my thoughts....
 

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#1.... we cut 1/4 scribe on a RAS in the 80's..

#2..... it was zero clearance on the RAS.

#3...... was it a 2" dowel being cut to 1.75 or was it a 36" dowel being cut down..

The problem hasnt been identified unless I missed something.
 

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I don't remember the company(companies) but there are places you can buy pre-made dowels from most any wood you want. I am sure a search will reveals these places.

I make my own much of time because the ones I buy local are cheap wood and often the sizes are not consistent. But if you use a lot of them I would just buy them.

That said, dowels are typically more for alignment then strength. Depends on what you are doing but if it is glue joint the glue is where the strength is, not the dowel.
脌 good glue joint is all you need. Just joint your edges to .001-.006" clearances. In a good joint the glue will be 125% stronger than the wood.
I felt the same as you until I watched a video on the relative strength a dowel, loose tenon or a biscuit has as compared to a good glue joint. The only joint that may increase strength is the spine joint.
 

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Woodworking novice here. "Hardwood" dowel pins have never seemed to have much density and I questioned their strength鈥攏ot specifically their shearing strength, but rather their resistance to general stress. The other day I got proof of the low quality of the 5/16" ones I was using. I was shortening dowel pins with a radial arm saw when one of them got out of alignment to the blade during the cut and it just exploded. It splintered and broke in many places. My reaction has been (1) to think maybe I should take the time to hand cut dowel pins in the future, and (2) to think maybe I should be cutting my own pins from hardwood dowels. It would be rather inconvenient, but is doable. Presumably the pins would need to fit in the hole not too tightly to allow for minor expansion from the moisture in glue, since I won't want to flute them. Wood density/integrity might not matter much for the larger pins, but I expect to use 1/4" pins more often than not. I'd rather buy better quality pins. It's not that I will be gluing up joints that will be under severe stress, but more that I want to be confident the pinned joint is strong in case it comes under temporary stress. Has anyone run into this before, and how did you resolve it?
1. I would say the first thing is I would question why you would try to shorten small dowels on a radial arm saw, seems like an accident waiting to happen. 2. dowels add to the strength of a joint as they add more glue area with a bonus of helping to align the two pieces of material. Good quality dowels are available from numerous sources and in most wood varieties. Good luck and stay safe.
 

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The exploding dowel could be number of teeth on the blade (lesser teeth tend to be more aggressive also feed rate is a factor), If I have to cut alot of dowels on the RAS I use a plywood blade, generally I use a bandsaw for just a few.,
 

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My thoughts exactly redeared...The smaller the stock, the more TPI on the blade, I think I heard it here that you should shoot for three teeth in contact with the stock at all times.
 

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Woodworking novice here. "Hardwood" dowel pins have never seemed to have much density and I questioned their strength鈥攏ot specifically their shearing strength, but rather their resistance to general stress. The other day I got proof of the low quality of the 5/16" ones I was using. I was shortening dowel pins with a radial arm saw when one of them got out of alignment to the blade during the cut and it just exploded. It splintered and broke in many places. My reaction has been (1) to think maybe I should take the time to hand cut dowel pins in the future, and (2) to think maybe I should be cutting my own pins from hardwood dowels. It would be rather inconvenient, but is doable. Presumably the pins would need to fit in the hole not too tightly to allow for minor expansion from the moisture in glue, since I won't want to flute them. Wood density/integrity might not matter much for the larger pins, but I expect to use 1/4" pins more often than not. I'd rather buy better quality pins. It's not that I will be gluing up joints that will be under severe stress, but more that I want to be confident the pinned joint is strong in case it comes under temporary stress. Has anyone run into this before, and how did you resolve it?
I buy dowel rod at the local hardware store (1/4" & 3/8") and cut to the length needed, usually on the band saw with a simple jig to hold it securely, safely and square. I then put the dowel in the chuck of my drill press and break the rough cut edge. I've found that there is some variation in the diameter of the dowel rods. Sometimes I have to use a slightly oversized or undersized drill bit OR sand the dowel as it spins in the drill press down a little.

I'm about do do a project with many dowel joints so all this work would be too cumbersome. Any suggestions??

I've seen some studies where they test the breaking point of various types of joints with hydraulics. Results were always that the 2 best joints are mortise & tenon and dowel joints about the same. Having had some glue-up panel joint failures I decided to added to add dowels as standard procedure.
 
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