---------------------------------------------------------- Avionics-List Digest Archive --- Total Messages Posted Mon 06/18/07: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:34 AM - Re: Antenna doubler plate - prime or not (Charles Reiche) ________________________________ Message 1 _____________________________________ Time: 03:34:42 AM PST US From: "Charles Reiche" Subject: Re: Avionics-List: Antenna doubler plate - prime or not You can prime it but I would spot face the holes where they pass thru the doubler on both sides and on the external skin from the inside, use the cork gasket. Comant wouldnt include it if they didnt want you to use it. The screws passing thru the antenna provide the connection to the ground plane thru the double and back to the skin if you use a spot facing brush. Make sure to seal the antenna with fuel sealant (if you want a long lasting seal that wont be affected by most anything) or use some RTV type bath caulk. The secret to smooth lines for taping the sealant line is to use 1/2" electrical tape of a good grade and leave 1/8" gap or greater. Tape down around using one hand to unroll it and your index finger on the other hand to get the spacing right as you bend the tape around the curve of the antenna, around the base your tape should look like a fish when you are done looking down... and at the back point, I just cut a 1" piece and square off the pointy part. This whole procedure takes some practice, work quickly with the glue as the 1/2 hour working time fuel sealant or RTV really cures fast in the summer heat. Have paper towel on hand or a helper with some to hand to you, use your fingertip to make the glue fillet, the edges should end at the edge of the tape lines so you make it pretty. As soon as the fillet looks good, peel off the tape so you dont get rtv curing to the tape. If you get ribbons of glue that fall down back onto the paint, its easiest to let them stay and cut them off after it cures. If you have not yet painted your airplane, DO NOT USE SILICONE RTV!!! Use fuel sealant, it can be painted over and up onto the antenna for a professional looking finish like the OEMs do. Good luck, Charles Reiche ----- Original Message ----- From: "Ralph E. Capen" Sent: Sunday, June 17, 2007 8:55 PM Subject: Avionics-List: Antenna doubler plate - prime or not > > I'm putting a comant bent whip on the underside of my RV6A. I have a good > doubler plate (derived from the AC43.13) - pictures if anyone wants to > see. > My question is should I prime it? > > My initial thoughts are that the existence of the metal structure will > provide the ground plane even if it is not bonded electrically to the > structure - meaning prime on...... > Otherwise, how is bonding effected as there is a cork gasket that is to be > installed? Do the four antenna mounting screws provide sufficient > bonding? > > Thanks, > Ralph ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message avionics-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Avionics-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/avionics-list Browse Digests http://www.matronics.com/digest/avionics-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.