Solar vent installation on CD 28

[Rebinva]

I plan to install a 4 inch Nicro solar vent in the foremost hatch on our CD 28. It requires a 4 3/4 inch hole. It looks to me as if it will fit OK, but, given my lack of skills for such tasks, Murphy could be somewhere in the neighborhood. Has anyone done this? What should I look out for? Any advice regarding this project would be greatly appreciated.

[Oswego John]

Murphy could be somewhere in the neighborhood. Has anyone done this? What should I look out for? Any advice regarding this project would be greatly appreciated.

Señor Murphy is always in the neighborhood, so you have to do your best to keep him at bay...You have probably heard the saying "Measure twice, cut once." When you are about to make a hole in your boat, measure five or six times, both inside and out before you drill once. If someone is around, I'd even ask that person to double check my measurement.

After deciding on the location of the hole, drill a small, maybe an eighth of an inch or so, hole in dead center of the proposed vent opening. Drop a nail or similar thin object through the hole as a marker and then go below to see if the location seems okay to proceed farther.

The reason to first drill a small pilot hole is if that site doesn't work out for any reason, it is not such a big job the refill the hole up. If you find that the vent hole must be moved, it is still possible to move the center of the hole about two inches in any direction from the original center without any major consequence.

I like to make large holes this size by using a hole saw chucked in a 1/2" drill motor. If you go this route, keep the first pilot hole no larger than 1/4". The center of the hole saw will ride in the 1/4" pilot hole and keep the new hole true and on center. You can usually rent a 4" conduit clearance hole saw from a tool rental company.

Some people prefer to use a saber saw to open the hole. I like to tape the area around the hole's perimeter to help prevent marring the deck as well as to prevent the edges from possible chipping.

So what can go wrong, you ask? There is a remote chance that you might cut into some buried electrical wiring, i.e. nav lighting, cabin lighting or anchor winch. Like I said, it is very remote that this will happen. You might be able to detect such wiring by turning the electrical power on to anything in the area and passing a compass back and forth around the area where the hole will be. You might see some deflection on the compass. Don't forget to have someone operate the winch motor while checking this out.

I think that it is better, at first, to cut the hole too small rather than too big. You can always trim the hole bigger, but not too easy to make the hole smaller. I like to tape the area of the hole and then draw cross hairs across the area. You can put masking tape on the vent base and make a mark on 90°s around the base. Holding the base marks over the cross hairs, mark the circle on the tape for custom fitting.

Good luck,
O J

[barfwinkle]

There is a remote chance that you might cut into some buried electrical wiring

OJ, he is putting the vent in the forward hatch!

[Carter Brey]

I installed a Nicro solar vent in the forward hatch of my CD25. There were no problems with the installation. I used a hole saw with a guide bit in the mandrel.

I found that the hatch had foam core; I removed this from the perimeter of the cut with a screwdriver at least as far out as the screw holes for the mounting ring and filled the space with thickened epoxy.

Active ventilation made a big difference in comfort at anchor and in reducing mildew during winter layup.

[img]http://pws.prserv.net/cbrey/5-25-040002.jpeg[/img]

Best regards,
Carter

[Oswego John]

Hi Bill. Another senior moment, I guess

In my mind, I had only one thought, (tunnel vision) (tunnel thinking)

All along I was supposing that the hole was going through the deck.

Good catch,
O J

[Rebinva]

one more question, since the hatch is lexan?, plastic of some kind anyway, what special precautions do I need to take.

[Randy Capstick]

I installed a Nicro 3000 Day/Night solar vent in the Forward hatch of my '74 CD28 and had no major issues. I cut the hole with a 4 3/4" hole saw/bit from Home Depot. Measure carefully, try measuring from below between the metal crossbraces, as I seem to remember it being a tight fit.

When you seal the vent, use the same color sealant as the vent's lower side. I used white sealant and it really stood out when viewed from below against the black innards of the vent. It really did improve the boats air movement and noticeably reduced the mildew buildup in the boat.

Randy

[seajunkie]

I put one in the hatch of my CD25. I couldn't find a hole saw that was the right size. I used the template in the box and made my cut with a jig saw. I used blue painting tape to mark out the area before making my measurements this kept the jigsaw from scuffing up the hatch.

[Steve Laume]

Yup, I mounted one of those puppies in my forward hatch. I looked all around and couldn't come up with a better spot for it. I didn't want to cut down on the amount of light that entered the boat but it didn't make much difference. It did make a huge difference in the dead air space in the vee berth. I made up a nice wood collar so the trim ring would fit on the inside. Otherwise it gets messed up by the reinforcements of the hatch. I think I used a saber saw with no problems. It is one of the least stressful holes you will ever drill in your boat. Steve.

[S/V Necessity]

Try running her in reverse slowly (after the pilot bit is already in) for a little bit in the beginning. It sometimes helps the hole come out a bit crisper and cleaner.

[The Patriot]

I plan to install a 4 inch Nicro solar vent in the foremost hatch on our CD 28. It requires a 4 3/4 inch hole. It looks to me as if it will fit OK, but, given my lack of skills for such tasks, Murphy could be somewhere in the neighborhood. Has anyone done this? What should I look out for? Any advice regarding this project would be greatly appreciated.

My CD28 has 2 19" Bowmar hatches with lexan inserts. I installed 3" Nicro solar vents in each of them quite some time ago and have no regrets. However I am wondering how well the larger 4" Nicro vent will fit between the aluminum cross pieces, since even with the 3" vents there is something of a tight fit. This may be because I also cut out 2 "donut-shaped" lexan pieces to reinforce the structure under the large holes when I installed the vents. These pieces are about 5/8" in width and take up a bit of space themselves.

Remember that you will probably have to use some sort of stainless machine bolts to secure the Nicro mounting rings. Be sure to insert rubber washers or something similar on the underside of the hatch so that there will be less chance of having the lexan crack under stress or temperature fluctuations. Also use a polysulphide bedding compound for the Nicro rings and tape everything very carefully. Stay away from either silicone sealants or adhesives like 5200 for this application. Finally if you follow the Nicro installation instructions carefully, you will find they are quite good and quite comprehensive.

One parting shot at Nicro. Over the years I have had to replace these vents from time to time when they simply failed. I don't know why they failed because they were not abused in any obvious way. I would guess that since the mid-1980's when I first installed them I have purchased in total close to 8 units (some of which were replaced under warranty). Despite these problems I would recommend these units very strongly.

[drb9]

Do you have problems with your head sail lines snagging the vent cover as you come through a tack? On my 25, which had a forward-mounted vent, those oval shaped holes were about the same width as my lines, so I had to remember to give the line a flip as I'm tacking so it didn't get hung up on the vent.

[Cathy Monaghan]

The Nicro solar day/night vents come in 2 sizes, a 3" vent requiring a 3 3/4" cutout and a 4" vent requiring a 4 3/4" cutout. For installation in a Bomar hatch, I recommend the 3" vent -- it's a better fit. If you decide to mount one through the deck instead of through the hatch, go with the 4" vent.

Fair winds,
Cathy
CD32 Realization, #3
Rahway, NJ
Raritan Bay

[Mitch F]

If you are installing it on the lexan hatch be sure not to use acetone. I thought I was being smart by giving the hatch a quick acetone wipe before applying sealant but it turns out that it will melt the lexan. I ended up with a fairly nasty but well ventilated mess.

[Warren Kaplan]

The nicro day/night solar vent comes with two props. One for bringing air into the boat and one that exhausts air out. The exhaust fan is the one installed as the unit comes out of the box.

My CD27 has a passive dorade vent and of course it has vents for the engine. For those of you that have installed active ventilation, like the nicro solar, which mode do you find more effective.....using it to blow fresh air in or using it as an exhaust fan?