The Final Coats of Paint Part II

Finally after much waiting due to family and work duties, as well as waiting for a good weather day we found time to sand and apply the final paint coat. In the previous painting, we found a lot of dust and paint globs had made their way into the paint. This despite 4 coats of paint and 2 coats of primer with sanding in between every other coat. The paint was nice and hard after a week of drying, but it just didn't look too good. Since our skills lie in electronic and not carpentry or woodworking it is not too surprising that we had some challenges with the finishing.

We decided that if the grills were not mounted on the speakers then the full front of the fascia would be exposed with all the dust and specks plainly visible. We had noticed that the RustOleum paint we choose blended very well with previous coats so we decided to paint just the front surface and leave the rounded over sides of the fascia as it was. We also decided that perhaps we had not been as careful in the sanding as we should have as well. No doubt those of you experienced in this kind of thing will find all of this a bit amusing, but we are true DIY speakers builders for sure, even if we are professional electronics engineers. The following photo shows the bottom of one of the Kitty Kat fascia which had the most dust of any of the five fascia.

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It became clear that we needed to find a better way apply the last coats. After online searches, we decided to build a very simple cardboard-box spray station. The following photo shows what we came up with:

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After wiping down the inside of the box we very lightly sprayed water to capture dust. The plastic drop-cloth allowed us to keep wind completely out of the box as we sanded and in between coats. The only challenge would be to see and breathe with our heads stuck inside the plastic. We purchased a breathing filter to help control the paint dust and solvents.

To prepare for the final coat and make a good attempt to remove the dust we used 320 grit Sandblaster Sponges and 400 grit 3M Sandblaster Pads sanding pads and sponges.

Here are the five fascia after the primer and main coats before sanding began.

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We sanded for almost 2 hours very carefully by hand just the fronts of the fascias as the sides seemed to have escaped the dust problem. We wiped up the paint dust with a moistened cotton cloth and let them dry for a period before painting. Here is a photo of the sanded and prepared fascia;

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Here are the Castia fascias sanded and placed inside the paint box ready for the final coats. To minimize dust we use a 3M microfiber cloth very lightly moistened with filtered water to wipe up the last vestiges of dust and lint inside the paint box.

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Here are the Kitty Kat fascia in the paint box after the final coats were applied:

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The quality of the paint was much better than any of the previous coats. Finally success! Here is a photo of the five fascia drying.

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After a full hour of drying, we moved the fascia inside and placed each one on top of the wired cabinets to harden up for a few days before we mount the drivers and begin listening!!! You may also notice one of our Thunder subwoofer cabinets in the top left corner of the photo. These will be the next project after the Casitas and Kitty Kats are done.

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Please see the next article in the series Mounting the Drivers and Final Assembly.

Copyright © 2010 David L. Bytheway