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Hey Guys,

I have a couple of quick installation questions on Capt. Patrick's original style Side Opening Air Boxes that are not covered in the instructions on the parts section of the website.

Shambala has hull gel coat that is in great shape and above decks gel coat that is in fair to good shape. Bottom line: the gel coat still shines above the hull, but there are not a lot of years of compounding left on the house structure. When I reach the point that the boot stripe on the house (Awlgrip Flag Blue applied in 2003) needs to be repainted, I will re gel coat rather than paint the house structure. I mention this as background information for these questions about the installation of Capt. Patrick's original style Side Opening Air Boxes.

The questions cover two areas: Cutting the hull sides and gel coating pre/post install.

Cutting Questions:

1. Does the template for cutting the holes in the hull sides attach to the inside of the hull or the outside of the hull? I initially thought inside because of the potential for rub rail interference on the outside, but then the space inside might be very tight to work a router as well.

2. Am I better off setting the plunge depth on the router and making a few passes or should I just cut the holes in one pass?

3. Do tape off the outside of the hull to prevent gel coat tear out/chip out or is that a non-issue?

4. Once the holes are cut, should I be going around the edges with a laminate trimmer and a small round over bit, or should I just use a block sander to hand "shape" the edges?

Gel Coating Questions

1. Is it feasible to prime and gel coat the inside of the air box prior to install to make the gel coat sanding process easier or are there connection points that must be gel coated/sprayed after installation to ensure a seamless post-installation appearance?

2. What grit do I need to sand the hole cuts down with prior to priming and gel coating.

3. Will I be gel coating the backside of the holes that have been cut (particularly the two vertical risers that divide the holes), or will that potentially interfere with the epoxy/cabosil adhesion points?

I just want to make sure I have conceptualized this correctly as I get close

Thanks in advance.

1. Does the template for cutting the holes in the hull sides attach to the inside of the hull or the outside of the hull? I initially thought inside because of the potential for rub rail interference on the outside, but then the space inside might be very tight to work a router as well.

The template goes on the outside of the hull.



2. Am I better off setting the plunge depth on the router and making a few passes or should I just cut the holes in one pass?

With the template screwed to the hull, mark the openings to be cut. Remove the template, and cut out the bulk of the openings, leaving 1/8" - 1/4" of margin to the marked lines. Re-install the templet and flush cut the remaining hull material with the router. You can do this in one pass. The more passes you make, (by not cutting out the bulk material and having to plunge route), the more chance there is for making a mistake...

I drill with hole saws the various spots that need a radius and then use a high speed grinder with a 4 1/2" thin metal cutting disc to come clise to "connecting the dots". A carbide blade on a jig saw completes the cutting.





3. Do tape off the outside of the hull to prevent gel coat tear out/chip out or is that a non-issue?

If you have the original chrome louver plates for the exhaust blowers, the new holes are not going to cover the original holes completely. Those two spots are going to glassed in, faired, painted, etc., and you'll be fairing the new holes, fairing the holes with the primary baffle, so there's really no need to mask...

4. Once the holes are cut, should I be going around the edges with a laminate trimmer and a small round over bit, or should I just use a block sander to hand "shape" the edges?

You could use a 1/8" round-over bit on the holes, but you'll still be hand sanding anyway. Again, the more you work that router the more chance of a "quick" mistake. Hand sanding is slower but far more controllable.

Gel Coating Questions

1. Is it feasible to prime and gel coat the inside of the air box prior to install to make the gel coat sanding process easier or are there connection points that must be gel coated/sprayed after installation to ensure a seamless post-installation appearance?

The primary baffle, the interior of which is visible is already gelcoated white. It needs to be thoroughly sanded before paint or re-gelcoat. The joint seam between the primary baffle and the openings of the hull should be sealed and faired in for the cleanest look. So hold off all topcoat finishing until after you're through with the installation and are happy with the results.

I would highly recommend paint as opposed to gelcoat simply because you'll have to sand and polish the gelcoat. Going to a real PITA doing that kind of work deep inside of those holes...



2. What grit do I need to sand the hole cuts down with prior to priming and gel coating.

For primer 320 grit; for gelcoat 80 grit...

3. Will I be gel coating the backside of the holes that have been cut (particularly the two vertical risers that divide the holes), or will that potentially interfere with the epoxy/cabosil adhesion points?

No. No finishing inside until you're done installing, Other than the dorade pan all else will probably be cover with SoundDown. On Hancocks B31 I even covered the pan...



This, of course, is Buddy Boy...

Patrick,

Thank you so much for all that great information.

I sincerely appreciate it!

John