Sealing the Black Plastic Eyeball Vent

TX7A · #1 08-17-2006, 11:13 AM

Okay...I give up!!
Somewhere there was some info on how to go about sealing the cheesy black plastic cabin vents where they wouldn't leak. Maybe something about making a homemade gasket of sorts.
Could someone point me in the right direction?

I "really" would like the aluminum Experimental Air vents...but 115 bucks each a little more than I want to spend.

Thanks

akarmy · #2 08-17-2006, 12:15 PM

I sanded the edges smooth and round, then covered the back of the flapper with green sticky back felt (like a jewlery box lining) from the hardware store. Wrap it around the edges and you have a nice felt seal that worked great.

I had no luck with the RTV gasket solution called out by Vans.

In the end I got the Aluminum ones and they are great!

DGlaeser · #3 08-17-2006, 12:48 PM

I also tried Van's suggestion with no success. The problem is that I have not found any glue or sealant that will really stick to that stuff!

My current attempt is to create a 'lip' for the flapper to seal against by cutting a 1/8" slice off of a PVC pipe (whatever size it is that is pretty close to the ID of the vent), and then cut it into a "C" that is placed against the flapper (one on each side) in the closed position. Sanding and trimming is required to make it fit well. I found some plastic glue that sticks OK to hold them in place. I'm not pleased with this solution, but it is the best attempt so far.

Has anyone ever removed the flapper and replaced it with something else? I may attempt that one of these days.

SteinAir has the cheapest aluminum ones I think @$100 each. If (when) I give up on the plastic ones, I'll go that route.

Norman CYYJ · #4 08-17-2006, 02:08 PM

I took the flapper valve out and sanded it using a very course sand paper. I then reassembled it, smeared vasoline in the tube and then caulked the flapper valve closed with silcone sealer all around the edges of it. I made a fillet in the silicone and let it set over night.
This method has work for me on several planes. My RV7 has over 300 hours on it and still no problem.

sf3543 · #5 08-17-2006, 02:28 PM

I used the VAN's vents on my RV6 and sealed them as he directed in the plans.
Basically, I cleaned the inside as good as I could with Isopropyl alcohol and then I put vaseline on the smooth walls of the vent. Then I globbed RTV on the flapper edges and closed it. (I may have globbed a little more on after that, too. Do this from the back of the vent.
The next day I opened the flapper and trimmed off the extra little pieces that I could reach and was done. If you use black RTV or silicone, it won't be noticeable. (I used black silicone.)
After 7 years and 900 hours, the vents still sealed great. I flew around in some cold weather and never noticed an air leak when they were closed.

Don Patterson · #6 10-20-2006, 09:34 PM

I made a modification to Van's plastic vents that now work as good as the all aluminum vents that sell for over $140.00 First you need to understand why it allowes air to leak past the flap when it is in the closed position. If you close the valve and hold it up to a light you will see a gap around the flap. I first removed the flap and opened the ID of the part on a lathe. Only the first 1-3/8 from the back which left about 1/2" of ID on the front part of the hole. Next I cut a disk of aluminum about .135 thick and about .005 smaller than the new ID of the part. Next I used a center drill and drilled a small point into the outside edge of the aluminum disk at 180 degrees of each other. The disk will pivot on the two set screws that where used on the old flap. Insert the new alum disk and lock it in with the set screws and you are done. I added a flat pice of aluminum to the face of the disk that is used to open and close the valve just like the original plastic ones and it works great. It took a bit of playing around with but I will use them and know that the cold Wisconsin wind will not enter through these vents.

DickDe · #7 10-20-2006, 11:10 PM

Quote:

Originally Posted by 7A_@ABI

Okay...I give up!!
I "really" would like the aluminum Experimental Air vents...but 115 bucks each a little more than I want to spend.

Steinair.com has them for $90 for the small and $100 for the large size aluminum eyeball vents. I used surplus DC10 vents as used in the passenger overhead vents but I no longer have a source for those...they are much better quality but are smaller so I have an "under the panel" vent to blow cool air over the lower body while the eyeballs take care of the upper torso.

Dick DeCramer
N500DD RV6
flying @ 155 Hrs
Northfield, MN

SteinAir · #8 10-20-2006, 11:43 PM

True...except our vents aren't anywhere close to the Experimental Air/Van's/Affordable Panels vents in quality - they're many steps above. We don't make the vents, they're from a mfgr that makes them for the military, Airbus, Embraer, Gulfstream, BAE and Boeing. If you take apart those other "aftermarket" vents you'll see that they are actually not all that well constructed, with only a tiny "felt" fabric gasket strip between the ball and the socket, and they're still pretty raspy & sticky to use compared to the mil spec ones.

The vents we stock (or try to, but have a hard time keeping them in stock) are mil spec quality, with a delrin/uhmw gasket held in place by an internal flat retainer spring around the circumference of the socket. This means the vents are smooth, don't stick open or shut (like the other metal ones have a tendency to do), aren't loose/sloppy and they will actually hold water they seal so good. I found them from my airline days and aside from Wemacs (which are identical in construction), I wouldn't use anything else.

Anyway, I used the plastic Van's ones on the 1st RV6...for about 30 minutes then burned them or threw them in the trash or something like that. When I built my -6 we didn't have access to these vents, but mine came out of a 747 cockpit back in my airline days.... If you spend more than a couple hours screwing around trying to get the plastic ones to seal up well, then you've wated enough time just to buy the good ones...plus they don't look like some $2.35 cent vacuum cleaner part installed in your $75K+ airplane!

Cheers,
Stein.

AntiGravity · #9 10-20-2006, 11:47 PM

How do you mount your ones Stein? They don't look like they're a direct replacement?

SteinAir · #10 10-20-2006, 11:53 PM

Quote:

Originally Posted by AntiGravity

How do you mount your ones Stein? They don't look like they're a direct replacement?

You're right! We decided to forgo the "4 hole" flanged vents (even though we could get them) because they waste a tremendous amount of space, both in a panel and below it.

So, we went with a perfectly circular vent that simply is inserted into a round hole (large or small depending on which vent you use), then screw the retaining nut or plenum on the back. No bolts, screws or huge flange to deal with - pure and simple. We mainly started buying these to install in panels we build, but they've become so popular that we're now buying more of them to stock/sell.

Perhaps I should get some flanged replacements, but I can't hardly stand wasting nearly 4" square of space to install a 2.xx" vent hence the decision to procure the ones we have..

Cheers,
Stein.