Make Accurate Dowels

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Introduction: Make Accurate Dowels

Store bought dowels can be problematic, they can be expensive, inaccurate as they're often made from not-fully-dried wood, and they can be limited to just a few species - locally I have access to Tasmanian Oak and Pine dowels only.

Making your own lets you use contrasting or complimentary woods, make them from scrap, or custom sizes otherwise unavailable.

Step 1: Tools and Materials

You will need

• Wood - hardwood, softwood, heck even plywood will do if you laminate.
• You'll need something for the jig (~200mm x ~45mm x ~90mm used in my example, you'll need larger for larger dowels)
• Something for the dowels
• Some scrap plywood to clamp across your router table that the jig is screwed into
• Forstner drill bit in the diameter you want the dowel
• "Complimentary" forstner bit to match the dowel (more on that later)

On the machine front, you'll want...

To clarify that a little, if you want a 19mm (~3/4") dowel, you'll need a 19mm forstner bit for the outfeed, and a 28mm for the infeed. More details provided in the next step.

Step 2: Lets Get Mathematical

To make the dowels, we feed square stock through a block, over a router table. That requires a bit of maths to get all the bits and pieces lining up right.

If you want a 19mm (~3/4") dowel, you'll need a 19mm forstner bit for the outfeed. For the infeed, you need a drill bit that'd match or exceed (slightly) the diagonal of the dowel size we want.

This works out at roughly diameter * 1.4, which gets us to 26.6mm.

If you want to be more accurate, use

InfeedDiameter = DesiredDowelDiameter * √2

As such a drill bit doesn't exist, the next closest thats larger is 28mm. Be aware that just because a drill bit says its X size, doesn't mean its true. On a scrap, drill a hole and measure with calipers - it may vary by +/-0.5mm and your calculations should be adjusted for the true diameter. That solves the first problem, but we can't have stock thats sloppy inside the infeed otherwise the size of the hole doesn't matter.

InfeedDiameter / √2

That gives us 28 / √2, which comes to 19.79mm, meaning we have to prepare a slightly-larger-than-expected blank.

Step 3: Drilling & Mounting

Once you've got your block, and have marked out all sides, at the drillpress you can drill holes for..

• infeed (the bigger hole),
• outfeed (the desired diameter),
• "escapement" (of chips) & router bit access - make these larger than the bit you're going to use to avoid too much jamming
• Mounting holes for bolts

You can then screw/bolt/whatever it to a longer piece of plywood which can be clamped at the router table. By using a "standard" (standard to you) placement of the mounting bolts, you can create multiple routing blocks and swap out for different size dowels and reuse the piece of plywood.

Step 4: Prepare Your Dowel Stock

You'll want to cut your dowel stock longer than you need so you've got something to grab onto to twirl around, and you'll want to cut it to the dimensions in the previous step. In my case, 19.79mm square.

The easiest/best way to do this is with a tablesaw using a featherboard to keep the pressure even.

Step 5: Make the Dowel

The square stock gets turned round by rotating it against the cutter - in this case/setup this works to be spinning it anti-clockwise.

The router bit needs to be raised up to the height of the outfeed hole.

The easiest way to drive the dowel is using a cordless drill with a socket attachment, but you can rotate it by hand. Once you get to a certain diameter dowel, you'll have trouble actually finding a socket that large, so you might consider cutting a tenon on one end or even drilling and installing a smaller dowel that you can just grab in the chuck.

Once you've got your height set, turn the router on, and slowly feed the square stock through the infeed hole, into the cutter, while rotating (at up to 500rpm).

Don't force it through, you'll feel it go through (or not if you've made mistakes).

On the other side should be your accurate sized dowel!

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Tips

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No reason this jig wouldn't work with a table saw doing the cutting instead of a router bit. You could also put a round end on square stock as for attaching a leg to a chair seat. Nice instructable!

Questions

On first glance I thought the jig you were using was clamped to your table saw - but then I realized it was on your router table. I really like this.

Nice jig setup, and very impressive results!

If it helps, my router table is built into the wing of my table saw ;)

Great size consistency, finish as smooth as you like, very fast, any size... what more do you want?
In my mind, there is now no better way to do it.
I'm impressed! Great Instructable. Thanks.

near as I can tell, the block mounts on the router table over any router bit you would care to use. Then use a drill with a socket to drive the square dowel stock through the large hole and against the router bit which makes the cut. Ingenious setup although not very well explained.

2 replies

In step 2, I start with the text "To make the dowels, we feed square stock through a block, over a router table. "

So... good guess ;)

I have to apologize. I scanned the instructable and then read the posts. This lead me to comment before I went back and read the entire instructable, which was a huge mistake on my part. Just scanning I missed so much detail. If I had read it first I wouldn't have posted what I did. You did an awesome job and now I'm going to have to build one for myself. Great job!!!

You didn't show how you set up your router.

Great idea, but what type router bit did you use. By the way the title said making dowels with a table Saw, not with a router. Might have been the root I& some confusion. I will definitely try this

4 replies

Also in the list of tools I said the actual bit doesn't matter - size, shape, etc. I mean, don't use a bearing guided bit as that'd not cut so good. I used a straight bit, a round nosed bit might be less aggressive and leave a cleaner cut, or even a downcut bit (which you wouldn't normally use on a router table for safety) may be OK.

OK Thanks.

I didn't put "table saw" in the title, and it isn't showing up as having table saw in the title (I just titled it "Make Accurate Dowels"). If it was there, that'd be the Instructables editors. :/

Well they must have doen so, but it became obvious that was not the case. You came up with a great idea.

This is quite good. I also appreciate the slightly rough and furry surface for bonding with glue. A bit of roughage. Very manly.
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I'd be inclined to make a tapered "feed in hole" to centre the loaded timber (think Morse taper) and incoporate a wider range of sizes of feed stock and I'd be using a 2 face pressure plate that holds the dowel in centre, but in a way that directly resists the throw of the cutter.

I feel like I learned a lot about drilling and measuring holes - is it the table saw blade cutting the dowel? The drill forcing the hole from one size to the other?