Wood’n Bits Workshop

Many miniaturists have used Preac table saws when they attend workshops.  While smaller in number, many have realized their usefulness and now have one in their own shops.

While many have the tool available to them, what’s not so available are people talking about how to use them.  Pete and Pam Boorman do put on well-attended workshops on Preac use and maintenance but it’s rare to find anything on the Internet about them.  I’ve decided to talk a bit about some of the things I do with my saw and how I do them.  Today I’m going to show you how to create a simple jig that will allow you to cut accurate miters.

The jig principle is simple.  If you start with a 90-degree angle and split it in half, the two pieces will equal 90-degrees, regardless of whether you divide it into two 45-degree halves or whether one is 44-degrees and the other 46-degrees.   We’re going to aim for two 45-degree halves but this virtue does allow some wiggle room.

What’cha Need

You don’t need much to build this jig and dimensioning the parts is easy with the Preac.

The jig base needs to be thick enough to be stiff while thin enough to allow the small Preac blade to still be able to cut wood that’s sitting on top of the plate.  Here I’m using a piece of 1/16″ cherry that’s a bit wider than 3″ and 2 1/2″ deep.  While this is reflected in the photos, I’d recommend you reduce the depth dimension to 1 1/2″ as I ended up cutting mine down to that dimension.

The other part that’s critical is the miter slot guide piece.  This must be the depth of the slot (mine is just a hair deeper than 1/8″ ) and the width of the slot (1/2″).  It should be about as long as the base is deep but that dimension is less critical.

The third piece is dimensionally less critical.  I used a rectangular piece of 1/16″ cherry as a start point but only because that’s what fell out of the scrap box.  What is critical here is that at least one corner of it must be perfectly square.  Use a square to ensure that this is the case and mark that corner with an X so you know which one it is.

Jig Assembly

1)Put the base on the saw, lining up the rear of the base with the front edge of the saw.  Ensure that there is about 1 1/2″ to the right of the blade.  While holding it in this position, mark where the center of the blade hits the blade and where the inside of the miter slot encounters the base.  Using a square on the rear of the base, draw lines perpendicular to the back of the base and up to the two marks you just made.

2) Use the saw itself as a jig to glue the guide to the base.  Apply glue to the guide, place it in the miter slot, and place the base in place such that the miter slot line and blade cut line are in proper alignment and the back of the base is aligned with the front edge of the saw table.  Unlike the photo, don’t have the guide protrude out the back of the base.  It’ll just make things easier when you try to trim up the back.

3) From the perfectly square (can’t emphasize that enough) corner of your small piece, measure back 1 1/4″ along each edge.  Draw a line across the piece between these two points.  This should form a triangle with two corners that are 45-degrees.  It doesn’t hurt at all to confirm that this is true.

Option: Some may want to cut along that drawn line now.  I didn’t and cut it after I’d glued it to the base.  It’s your choice.  What’s important is that the two ends of the line be well-marked as you’ll use these to set this piece relative to the rear of the base.

4) Set your fence for 1 1/4″ and cut both sides of the fence so that they measure 1 1/4″.  This should cause the saw blade to cut right through the two end marks you made in the previous step.  As you can see, the marks aren’t necessary but I like to do this as a double-check as I’m cutting.

5) Glue the small piece to the base, aligning the two measured points to the rear of the base and with the front corner centered over the blade cut line.  Make sure that no glue remains along its edges.  You want these “fence” edges to be clean and perpendicular to the base.  You might also use a 45-degree triangle as a double-check.  This should be the angle between the fence and the miter slot.

5)  At this point the fence piece will be sticking out behind the base if you haven’t already cut it off (see Option).  This doesn’t matter at all so if you just want to leave it there that’s fine.  Otherwise, you can carefully use your Preac to cut it off but some might feel uncomfortable doing this.  I wouldn’t do it on any table saw other than a Preac as it’s not quite as stable as it should be.  A handsaw could be used as well.

6) Say “Jigs are useful – jigs are good” a few times.  You’ve just created one and thinking in terms of creating jigs and fixtures is the road to being a successful woodworker.

Cut some miters

Place a stick on the left side of the jig and cut, you’ll get one half of a complete miter joint.  If you were very precise in your jig construction the angle will be 45-degrees.  If you weren’t it might be a bit less or more than that.  If you then cut another stick from the right side of the jig, you’ll get the second half of a miter joint.  And when you put the two pieces together will form a perfect 90-degree miter joint.

I hope you find this jig as useful as I have.  I use one on my full-size table saw as well as on my Preac and it turns picture frame or face-frame miters a no-brainer and I’m really good at no-brainers.

Cheers — Larry

larry@woodnbits.com

Cutting miters

• Bookmark on Delicious
• Digg this post
• Recommend on Facebook
• share via Reddit
• Share with Stumblers
• Tweet about it
• Subscribe to the comments on this post

Tags: Jigs and Fixtures, Power Tools, Table Saw

This entry was posted by Larry on Saturday, April 25th, 2009 at 5:47 am and is filed under Miniatures, Tools. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.