I started construction by sawing the boards of MDF and Birch plywood to usuable pieces. For this I used a hand circle saw, for two reasons. Although I have access (my dad has a great collection of powertools) to a table saw, this table saw was abused for cutting firewood. Which is a shame because it's very good one, with a sliding table mounted to it for easier ripping. Second reason: Table circular saws scare the h*ll out of me!! I personally know three people, who after a careeer of tens of years (My uncle who owns a sawing mill, my neighbor who has a kitchenbusiness, and a friend of the family who has owned a table saw for decades) have cut off several fingers with one. I don't get near one, if I don't have to! Since a hand held one needs to be handled with two hands, I think it's safer. The result of a days worth of sawing (one obvious disadavantage, besides accuracy, is that a hand held circular saw is way slower) is a nice stack of panels.
Next, I made a mould out of a 9mm thick piece of mdf for the front baffle. I used my my new router for this, together with the circle jig. I thought that would be the difficult part, but making the square cutout for the Raven proved to be quite a challenge. I asked some advice from my neighbor, the one who owns the kitchenbusiness, and he gave me the tip to screw 4 small battens on the mould and use them as a guide for the router, after cutting a rough hole with the jigsaw. Further on, you can see a picture of how I used this technique to make a cutout in the side panel
On this image, you can see a few steps in the construction process together. I have made the baffle using the mould of the previous image. I glued together the two panels of MDF and Birch plywood. I also made a bevel in the cutouts for the woofers in the MDF panel. This was done because the front baffle in total is 40mm thick, if I had made a circular cutout, the woofer would be mounted in a small tube with only a small opening to vent the backwave of the woofer. The magnet of the woofer would have almost plugged this tunnel, the bevel makes sure that this does not happen. I have also already mounted the threaded nuts in the MDF, which will later be used for the screws that hold the woofer. The clamps you see are for the glueing of the small panels that make the narrowing in the frontbaffle.
Here you can see the resulting baffle from the back. The three small pieces of birch plywood are in place. The MDF panel already has a cutout for this narrowing, the birch panel hasn't. In this image you can also see that I used T-nuts to mount the Raven tweeter.
A close up of the narrowing. I first used the jigsaw to make a rough cutout. I then used the the three panels, using the "valley" as a guide for the template bit to finish off the edge. Also visible are the countersinks for the drivers. I made the using the same mould, but mounting different seized guide bushings on the base of the router. The large guiding bushing (or ring) was for routing the hole through the panels, the smaller one (with the router depth set to 5mm) made the countersink. I had some luck with the countersink for the Raven. In my set of routerbits is a 12mm bit, which is just right for the corners of the Raven countersink, so no extra work was needed there!
Here I glued on the two panels that create the sub-enclosure for the tweeter
When I started on this little adventure, I was convinced that making the circular cutout for the woofers would be the most difficult to get right. Well, I was wrong. Making circles is relatively easy. When you need two identical baffles, you simply make a mould from a €1 piece of MDF, using the circle jig for the router. Within 5 minutes you can have a perfect round circle, of exactly (within 0,5mm) the right diameter, and in exactly (again, within 0,5mm) the right place. Making square cutouts in the right place, perfectly squared and of the right size turned out to be the biggest challenge for me. This little trick I learned from my neighbor and was also used to make the cutout for the tweeter. How does it work? Well, pretty simple actually. I wouldn't have thought that it could be done so easy, after spending nearly a day fiddling around with a jigsaw and a ruler! Just mark where you want the cutout to be on the panel. You then mount small battens exactly on these markings. That needs to be done meticilously and is the difficult part of the operation. You then make a rough cutout with the jigsaw, sawing as close to the battens as possible. Then you take your router and with the template bit, using the battens as a guide, you can remove the remaining edge. This will leave a small edge in the corners, but for this five minutes with a chisel is all you need.
I used plenty of clamps to hold the front and side of the speaker in place when the glue settled. I also made an extra jig to apply extra pressure on the small panels of the narrowing, to make sure they were glued airtight. I used the panel that will become the top of the speaker to make sure that the two panels were mounted square. After the glue had set, it turned out that this worked.
Here the backside of the subenclosure for the tweeter is glued in place. Now the Raven has it's own little airtight home in the cabinet. Free from the pressure waves produced by the Scan Speaks.
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