The Parts Express finished cabinets come with a removable front baffle, which allows the baffles to be worked-on without too much difficulty. However, they are pre-finished, and it takes a bit of care in working with them to prevent damage. Likewise, driver flush-mount cutouts in general can be a little tricky, even on a standard non-finished cabinet. So, I'm hoping to share some tips for working with the PE blank baffles, but much of the information carries over to other cabinets in general.

Cutting the baffles for the Morchellas

I always start the process by putting a protective film over the front of the baffles. This will prevent them from being scratched by handling or from the routing process. No matter how careful you are with your routing, with all the MDF dust and friction between the paint and the router base, scratching is pretty much inevitable. So, by placing a film on the surface right off the bat, we can avoid this problem.

I used to recommend Duck brand "Roll-on" Easy-Liner repositionable shelf liner, but they appear to have recently changed the formula. It used to be a paper-based product, but it is now a plastic-based product like many of the other liners out there. If you can find the old-style paper material, I would highly recommend it, otherwise any Duck brand or Contact-type paper should work. I found a new product at Lowe's made by Duck which was a granite-looking textured shelf liner. This seemed to work better than standard Contact paper because it is a slightly stiffer material, and the textured surface leaves some room for sawdust to move around.

I prefer to do all of my driver layouts from the back side of the baffle. This way you have clear edges to make your measurements from, as opposed to having to base your measurements from the rounded edges on the front. So, the first thing I do is make a center line running the length of the back side. This way I know that all of my driver cutout locations will be "lined up" vertically on the cabinet. (Or, if you are offsetting a tweeter, you still have a baseline to measure the offset against). Then, I find the center of that line, which is the exact center of the baffle, and lay out the driver locations relative to that point. This is done by a combination of taking driver measurements and actually laying them on the back side of the cabinet.

After I have the center points of my drivers on the rear, I use a 1/8" drill bit and actually drill through from the back side to the front side. This not only transfers the centers of your driver locations to the front, but it will also provide the center pivot point for use with a Jasper circle jig. However, it is important to keep these through-holes as perpendicular as possible to the surface, otherwise the location on the front sides could wander. A drill press works great for this, but it can be done with a hand drill and some care too. You may need to "clean up" around the holes on the front side a bit, as they have a tendency to get bulgy as the bit goes through. Using a utility or other knife will make this a simple task. Note: in this picture, the center to center distance of the drivers says only 4-1/4" inch, but after leaving only about 1/64th of clearance between the woofer and tweeter, I decided to increase this to 4-1/2" for the writeup.

So, now that I have my center locations on the front of the baffle, I draw some "crosshairs" though the center point. To do this, I use a framing square, making sure to draw lines that pass through the 1/8" hole. This is only really necessary when using templates or non-round cutouts. If you will be using a jig on both holes, these cross hairs are not needed.

For this particular design, we are using a square-faceplate tweeter that needs a round through-hole. I decided that it would be easiest to make the through-hole first, and I chose to use a 2" hole saw. This creates lest dust than using a router, and I find it a less stressful process. Since I already had my 1/8" pilot hole through the center location, it was easy to center the hole saw. Tip: you will need to raise the hole saw frequently and "clean" the teeth to prevent burning of the MDF.

Lets take a break from working on the baffle for a moment, and switch to working on building our template for the square tweeter. As mentioned in the writeup, we are using a 1/2" bit, a 5/8" collar, and a 2-1/4" template. In reality, you probably want to make the template slightly bigger than 2-1/4" (maybe an extra 1/64" or 1/32" or so, depending on the precision of your tools) to give yourself some room for error and allowance for tweeter variances. There's nothing more frustrating than a driver that won't quite fit into its recess! For simplicity's sake, we will continue to refer to this as a 2-1/4" square, even though it should be slightly larger.

So, my trick for making these square templates is to start by ripping a fairly long strip of the 2-1/4" width from a piece of 1/2" MDF. Cut this strip into 2 longer pieces and 2 shorter pieces... the exact lengths of these pieces does not matter, but the long ones should be roughly 3 times the length of the short ones. Now, we lay out these pieces with the two long ones at the top and bottom, and the two short pieces next to each other in the middle. Adjust the middle pieces so that they are 2-1/4" apart, glue the pieces together, and you have your 2-1/4" by 2-1/4" perfect square. As long as your cuts along the way are reasonably accurate, you should get a perfectly square template every time. I don't know of any other easier way to make this type of template.

Now, back to cutting baffles. Thanks to our handy crosshairs around the tweeter cutout, we have a clear reference for lining up the template on the baffle. Align the corners of the template with the crosshairs, and you are all set. Clamp the template in place securely, and it is a pretty easy task to make your tweeter recess.

Now, we cut the woofer recess using the Jasper Circle Jig. This is a pretty straightforward process, and is pretty much the same as how you would do it for any cabinet. The only thing I would note is that you will often get more "fringing" of the protective film when cutting in one direction vs. the other, so you may want to experiment with that. I believe that you want to cut in a clockwise fashion for the least tearout, but this is working from memory, and it's been a month or so since I've cut any baffles-- so try it yourself!

Now that we have all of the driver recesses and cutouts, we can remove the protectant. At this point I also like to "blacken" the edges around my recesses, to minimize the visibility of the space between the woofer frame and baffle. I like to use a large permanent marker, which is usually sufficient to prevent the seam from being visible.

So, that's about it. It's a somewhat time-consuming process, but if you work carefully, it isn't too hard to complete the baffle cutouts successfully. It is important to use a sharp router bit to minimize any chipping or chattering around the cutout edges; I find that a solid carbide spiral upcut bit works well. In the worst case, if you have chipouts or damage to the front baffle, you can spray the entire baffle with a black spraypaint-- it actually does a good job!