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Phil Thien
11-08-2008, 9:18 PM
After writing about my "sliding doweling jig" (based on a jig I saw in Fine Woodworking), I heard from a number of people that complained that: (1) They had difficulty drilling perfectly straight holes that are 1-1/2" deep and (2) They've had trouble locating the spacers I use as bushings.

I've also thought long and hard about doweling jigs and how I could improve my design. To make it more universal, so that it could be used in table stretchers and face frames and cabinet carcases alike.

While I was doing my thinking, I discovered that Rockler now sells an inexpensive doweling jig (only $9.99 as of this writing). Here, this one:

http://www.rockler.com/product.cfm?p...er=dowel%20jig (http://www.rockler.com/product.cfm?page=18059&filter=dowel%20jig)

It is simply a hardened drill bushing with two 3/8" holes, attached to a transparent guide featuring center lines. Rockler seems to really be pitching it for face frames.

So I purchased a couple of them to experiment with, and I've come to the opinion that it actually ideally suited to all sorts of doweling tasks. With a little modification, that is.

The clear plastic guide has got to go. First, it is too slippery and when clamped to the workpiece is inclined to allow movement while drilling. Second, I don't like referencing from the center of the holes of the guide. I prefer to reference from the edges of the steel bushing instead.

So I made three new hardboard guides to replace the original transparent guide. Each board is sized according to its use: (1) This first guide is for face frames, and is 1-3/4" wide and 4" long. All my face frames are 1-3/4" wide, and the steel drill bushing is 2" wide. So using the edge of the steel drill bushing as a reference won't work. BUT, by attaching a 1-3/4" wide hardboard guide, I can now use the edge of my shop-made guide as a reference. I simply align the edges of the guide with the edges of my frame member, clamp, and drill my two holes. I don't think it could be any faster.

(2) The second guide is for edge-drilling cabinet pieces, and is 2" wide and 4" long. It is a little redundant, as the 1-3/4" wide guide would have sufficed. At the time, I supposed the extra width would help in gripping the workpiece. But with the use of the non-slip stair tape (see below), that really isn't a concern.

(3) The third and final (so far) guide is for face-drilling cabinet pieces, and is 2" wide but only 2-1/4" long (so it extends only 3/4" below the bottom of the steel drill bushing). This allows me to drill face holes in cabinet pieces.

Each of my shop-made guides has non-slip stair tape covering it entire face. The non-slip tape extends all the way under the steel bushing. This tape provides a death grip that prevents the bushing from moving while drilling.

While doing cabinets, the two pairs of outside holes (flush front and flush back) are easy, just align to the edge of the steel drill bushing, clamp, and drill. For holes in the center of the panel, simply use your combination square to locate the steel bushing. You can easily drill four sets of two holes with a single combination square setting (one referencing the front edge of the piece, one referencing the rear edge of the piece). If you need more, use two combination squares, or make a jig that references from previously drilled holes.

I've included some pictures showing the unit in its various configurations (under use), and some of the results. I'm extremely happy with the outcome. Edges are perfectly aligned, and it requires minimal effort to achieve excellent results. Cost is nominal, and the design is flexible enough that I can easily add spacers for things like offset joints.

I'm happy to have another alternative to joining wood that is strong, flexible, and very inexpensive.

If there is any interest I have important information for others that might want to try duplicating this. But I don't want to get too technical in a first message.

I have concluded that a drill bushing with two holes is actually ideal when it comes to flexibility. You'd think two holes is going to require excessive repositioning. That, four or five holes would be wiser. In reality, though, I don't often want to run a line of four or five holes in a row, you don't need that many closely spaces holes in a cabinet joint. And for something like an apron to leg joint, it is easy to get four holes with a single move of the jig, and the holes are arranged symmetrically in the joint. And for face frames (where two holes is obviously ideal) you don't struggle with a bulky jig that wants to fall off the frame member while you're trying to clamp it.

Phil Thien
11-08-2008, 9:22 PM
More pics...

Tim Thomas
11-10-2008, 8:56 AM
Phil, you have done it again. I think you should adopt the BASF motto:

"We don't make a lot of the products you buy.
We make a lot of the products you buy better.™"

Jim Becker
11-10-2008, 9:06 AM
Nice adaptation, Phil. I may pick up one of those and modify as you did just to have one around!

Dewey Torres
11-10-2008, 9:06 AM
Nice work Phil. I know this post took some time. Thanks for putting it together.

Alan Tolchinsky
11-10-2008, 5:27 PM
More pics...

Hi Phil, That's a great idea! One question? How can you get perfect spacing between two sets of holes? It would seem if you are a little bit off that the four dowel joint wouldn't work. I don't do much doweling but it looks like spacing between sets of dowels would be critical. Thanks

mreza Salav
11-10-2008, 6:06 PM
Thanks Phil.
How accurate is that jig from Rockler? If it's accurate enough, it surely is a very good deal.

Phil Thien
11-10-2008, 7:12 PM
Hi Phil, That's a great idea! One question? How can you get perfect spacing between two sets of holes? It would seem if you are a little bit off that the four dowel joint wouldn't work. I don't do much doweling but it looks like spacing between sets of dowels would be critical. Thanks

It is all a matter of referencing from something.

Using the 2nd photo in my second post (four dowels) as an example. Let's imagine this is an apron for a table, and that those four dowels will go into the leg.

(1) I mark the edge of the apron pieces that will be UP (towards the top of the table) with my pencil.

(2) I flush the edge of the jig to that edge (the UP edge), clamp, and drill my two holes.

(3) Now I flush my jig to the opposite edge of our apron (the implied DOWN edge), clamp, and drill my other two holes.

(4) Before removing my jig, I set my combination square so the head rests on the UP edge, and the blade touches the jig that was just used to drill the bottom two holes.

(5) Now the combination square is set (you only need to do this once), so you can drill the rest of the apron pieces.

(6) When you drill the legs, place the jig flush to the top of the leg, and drill your first two holes.

(7) To position the jig for the bottom two holes, use the combination square that we set earlier. Reference from the top of the leg, clamp the jig, and drill your holes.

That's pretty much the same way all the doweling was done when I was in high school. We just used our combination squares to locate our jigs on the workpieces.

Phil Thien
11-10-2008, 7:16 PM
Thanks Phil.
How accurate is that jig from Rockler? If it's accurate enough, it surely is a very good deal.

That is an EXCELLENT question. I only have two right now. If I stack them one on top of the other, and place two 3/8" drill rods through the holes, they are perfectly aligned with one another.

But two isn't an exhaustive analysis. I've ordered three more. I would like to give two of them away as Christmas gifts to friends (big spender, eh?), and by ordering a third I was able to get free shipping.

So when they arrive I'll report back with an analysis of how accurate they are.

Robby Tacheny
11-10-2008, 7:29 PM
Is this jig on center for 3/4" boards?

Thanks for the pics!

-R

Alan Tolchinsky
11-10-2008, 7:41 PM
Thanks Phil, That makes sense to me. I guess that's the way Dowelmax does it if I remember correctly. It uses a rod to get a perfect distance between the dowel sets. Very ingeneous on your part!

Phil Thien
11-10-2008, 11:02 PM
Is this jig on center for 3/4" boards?

Thanks for the pics!

-R

Yes, the steel drill bushing is 2" wide, 1-1/2" high, and 3/4" thick.

The holes are 3/4" on center, and the pair are centered in the bushing.

Steve Kosh
11-12-2008, 3:22 PM
Wow, Rockler must have seen this thread and raised the price a buck ($10.99 now).

Phil Thien
11-15-2008, 12:15 AM
Thanks Phil.
How accurate is that jig from Rockler? If it's accurate enough, it surely is a very good deal.

Ok, now that I have several of these, I was able to take some measurements and compare.

I found that the tolerances are plenty tight. All the critical dimensions (basically, centering of holes within the block) were +/- .003". I got a single "bad" one where one of the holes causes my bit to bind ever so slightly, though.

+/- .003" is plenty accurate for drilling dowels. But then I got to thinking...

These are hardened steel. I often use my Ridgid oscillating belt sander to clean-up bad chisel edges (found at rummage sales) before sharpening them on my WorkSharp.

So I decided to get extreme and fine-tune the Rockler jig on my belt sander. With an 80-grit belt (an old one that has seen plenty of chisel action), I was able to get the critical tolerances to within .001".

I don't know why I did that. But I guess if you get one that is more than +/- .003" it would be pretty easy to get it to perfect if you have a stationary belt sander.

When I was done sanding it I finished it with some cold-bluing solution and then hit it with a little steel wool, so it even looks nice.

Ed Baggett
05-14-2009, 12:39 PM
I just wish they had one for 1/2" boards

Thanks for a great post Phil

Gary McKown
05-14-2009, 2:42 PM
I just wish they had one for 1/2" boards

Wouldn't this just be a matter of adding an extra 1/8" hardboard spacer to the clamped extension?

Mike Gager
05-14-2009, 4:18 PM
only thing about phils version is it takes away the one thing that i liked about the rockler jig, the ability to see the center line you mark on the work pieces


i think i will have to try making one of these myself

Jerry Murray
05-14-2009, 6:48 PM
Phil,

Great idea!

I just made the baffle fro my DC system and it works absolutely wonderful...now I'll have another project! :D

Mike Gager
05-14-2009, 8:12 PM
alright here is my version of the rockler dowel jig

118335
118336
118337

just a scrap piece of oak and a piece of 1/4" acrylic. i used 1/4 holes for the dowels because i had a few 1/4" dowels laying around

however i am having the same problem with this one as phil mentioned about the rockler version, the acrylic is too slippery and slips in the clamps as you drill. im going to get some sticky sand paper as he did but keep the clear base so you can see the layout mark and see how that goes.

Phil Thien
05-14-2009, 11:28 PM
alright here is my version of the rockler dowel jig

Nice work, Mike!

For a center reference I used a diamond scribe to mark the Rockler drill guide itself. I almost always use edge referencing but the center line comes in handy at times.

To get the line perfectly centered on the block, I carefully set my combination square and scribed two lines, one with the square registered from the left side of the block, and the second with the square registered from the right side of the block. By carefully setting the square you can make the two scribed lines overlap, so you know you have marked dead center.

Rich Engelhardt
07-25-2011, 6:09 AM
however i am having the same problem with this one as phil mentioned about the rockler version, the acrylic is too slippery and slips in the clamps as you drill. im going to get some sticky sand paper as he did but keep the clear base so you can see the layout mark and see how that goes.

Here's an update/tip for anyone that cares.
I picked up one of these recently - they are up to about $15.00 now but, still a good value for the occasional user.

I dabbed some Zinsser Seal Coat on back of the stock clear acrylic.
Works like a champ.
The shellac is thin enough that it doesn't change the center of the jig on 3/4" stock.
It's clear enough so you can still see/use the markings.
It takes away the slip of the acrylic so now only moderate clamping is needed to hold the jig in place.

I drilled 18 holes yesterday and it worked the same on the last two as it did on the first two.
If/when the Seal Coat wears off, another quick swipe of it will put it back in order.

Dan Cameron
07-25-2011, 11:34 AM
Just use a 1/8" spacing plate between the mounting plate and the board.

Ed Baggett
01-14-2012, 9:19 PM
I just received the 1/4" version.

Thanks Rockler

John Hollaway
01-15-2012, 3:52 PM
Phil, I'm only guessing here, but you appear to dislike pocket hole jigs & screws. May I ask why?

Phil Thien
01-15-2012, 6:06 PM
Phil, I'm only guessing here, but you appear to dislike pocket hole jigs & screws. May I ask why?

Au contraire. I like pocket hole jigs quite a bit. I only have one of those little $30 Kreg kits, but it works great and I've built several things with it.

One of these days I'm going to get one of the K3 kits.

I will say that I have had a couple instances of making face frames from walnut where the screws have split the stiles (funny grain). So if I'm working on something where I'm nearly out of wood (that happens quite a bit) I will often use my mortising or doweling jig, just to be on the safe side.

Rich Engelhardt
01-16-2012, 6:48 AM
One of these days I'm going to get one of the K3 kits
K3's are getting hard to find.

Phil Thien
01-16-2012, 9:22 AM
K3's are getting hard to find.

I know, but I like the design more than the K4.

Van Huskey
01-16-2012, 6:55 PM
I know, but I like the design more than the K4.


Agreed, the front vs rear clamping is a big deal to me anyway.