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Woodworking novice here. "Hardwood" dowel pins have never seemed to have much density and I questioned their strength—not 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?
 

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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.
 

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I don't use dowels often. My understanding is the same as Kudzu's. Dowels are to ensure alignment when assembling. After assembly, the dowels don't increase the strength of the joint by any appreciable measure.
 

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Termite
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Have dowels in bread board ends. More than alignment going on there...

Me and my son in law are making a gate for his stairs. Do you think Dowling these wont help. Glue will be enough?
20210515_101806.jpg
 

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Thanks for the responses! I can't imagine how I never learned that dowel pins are mainly for alignment—perhaps it never registered because my skill at drilling at a consistent offset from an edge is poor. I can understand that a biscuit (cutter) is relatively easy to use to cut at a consistent offset, though. Certainly the glue + clamping I do creates a joint stronger than wood (although it is more prone to wood delamination at the glue line). Perhaps all I really need is to rethink whether, given a specific situation, I really just need a stronger joint (mortised, rabbeted, dovetailed [although I can't cut dovetails], etc.).
 

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Greg if you get a doweling jig (I use the DowelMax), you can get very accurate alignment of edge and end grain joints with dowels. And I would say the strength of those end grain joints are in the same league as M&T or other loose tenon joints, depending on how much wood you put in there. You can find strength tests on youtube.
 

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Rebelwork, If I were making the gate... I would consider half laps or bridle joints, especially if used for children's safety.

Another consideration would be to use plywood for loose tenons if in your case the framework was already cut to size. Plywood will lend strength and stability in each direction of the grain.
 

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David
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I was shortening dowel pins with a radial arm
That alone seems dangerous. I use my 12" bandsaw or cut by hand if I need to shorten a dowel.
 

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Thanks for the responses! I can't imagine how I never learned that dowel pins are mainly for alignment
Well, you never learned that because it flat out isn't true. A dowel joint is barely behind a mortise and tenon joint in terms of strength, if dowels are only for alignment, so are m&ts

Having a dowel explode after binding with a saw blade is hardly surprising. It's a slender piece of wood impacting something at 60mph, not like it's going to stay intact. Drop a 2x4 on to a running saw blade and it'll be worse for wear too
 

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Strength of dowels? Let's picture two pieces, glued end to end with a dowel centered to locate them. If you twist one, once the glue fails, it will rotate around the dowel because it is round. If you try to bend the two pieces, it will likely break at the glue joint.
Using the same size two pieces, but with a mortise and tenon joint, twisting will likely break the surrounding wood with much greater resistance to the twist. A square peg will not rotate in a square hole, unlike a dowel. Bending the assembly will also offer more resistence because of the shoulder on the tenon. Dowels do not have shoulders, so their strength relies soley their diameter. A 1/2" square section of wood has more area than a 1/2" diameter dowel, so it's stronger.
 
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This is how we were doing it in the early 80's. Been on the hunt for one for a while. . This one os not the same but similar
5761-A.jpeg
 

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I use dowels quite a bit and haven't had problems with strength. I usually buy dowel rod and cut what I need with the scroll saw. For the place for glue I usually cut small notches all around them also with the scroll saw. If anything breaks it's almost always the wood around the dowels themselves so to compensate I'll usually make through dowels and pound them all the way through and trim off the excess.. Lots of work if you're using a lot of dowels.. I've made chairs and tables with dowels quite often..
 

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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.
 

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I use a lot of birch dowels, which I buy in 3 foot lengths, and also a lot of small splines, which I make out of maple. I find it is much safer to cut both into short lengths on a bandsaw as difalkner suggests.
I find splines work better in corner joints. There's more side grain to side grain contact than with dowels.
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And dowels work better in stile and rail joints. They need deeper penetration into the stile since the round shape has less side grain to side grain contact and doesn't glue as well.
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I machine the splines about 0.005" undersized for a slip fit into the routs. I like dowels 0.003" to 0.005" oversized for a drive fit into the holes.
In high production, dowelled joints in doors develop enough strength in few seconds to be taken out of the clamp and, if handled with reasonable care, not shift out of square or loosen up.
 

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I buy my 3/8" x 1.5" fluted dowels by the 1000. (much cheaper that way).
That's all I've used to join my face frames for cabinets for over 35 yrs now.
Never had a problem with strength, they are probably 10 times stronger than needed so anything stronger
is a moot point. It's irrelevant.
I've tried to take a joint apart only seconds after gluing together wrong only to bust the frame instead.
The pre made fluted dowels I use expand after installed with glue and are impossible to remove without damage.
Strength is not a factor. Cabinets and furniture don't need to be able to lift a car.
 

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I am still trying to understand the OP's issues (@GregJ7).

If the question is solely about dowel pins exploding when shortened on a radial arm saw, then my response would be to question whether the radial arm saw is the best tool for that job. I wonder whether this is just a simple clamping or tearout issue? Dowel pins are round, so supporting them to avoid tearout on a radial arm saw may not be easy.

Radial arm saw blades should have a negative hook angle, and I wonder whether that contributes to the tearout/explosion issue. Dumb question: Is the blade sharp?

Does Greg use some kind of jig? Perhaps scrapwood with properly sized dado slots to surround the dowels would help.

For small projects like toys, where a few dowels are needed, I cut them to size from various hardwood dowel rods. I use a mini hand saw and miter box like these (available from Rockler, Woodcraft, Amazon,etc.):
https://www.zonatool.net/cat/razor-saws-miter-boxes/miter-boxes-and-razor-saw-sets/

For quantity uses, I use bags of pre-made dowels with flutes cut in them. I have several really old doweling drill guides that I inherited or picked up over the years, and haven't figured out which one I prefer.
 
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