Baffle Seal Material

[belloypilot]

I’m looking for input from the FlyHusky brain trust regarding baffle seal material. I’ve always been skeptical of the ‘typical’ material used for baffle seals. It always seemed too rigid and prone to further hardening over time. There must be good reasons for that material being used as it‘s rather ubiquitous, but I’ve used other material with what appears to be good results. My Bonanza has a Beryl D’Shannon system that uses a much softer silicone material that’s molded to the contours of the mating surfaces. It feels so flexible you’d think it wouldn’t stand up, but its nearly perfect after 21 years.

I also have some recent experience with the McFarlane Cowl Saver product. Also a softer silicone product but not molded and a bit more rigid than the BDS product. It comes in a roll and is cut to length and shape like conventional material. I just had it installed in my Acrosport and it made a very noticeable difference.

Anyone have experience with these or similar products on their Husky? Any recommendations?

 

[bumper]

For your cowl saver, and to reduce friction between baffle and cowl, and thus preventing engine vibration from being transferred to the airframe, use UHMW-PE* tape on the inside surfaces of the cowl wherever baffle material touches it. This tape is exceptionally wear resistant and almost as slippery as Teflon - but much stronger.

Silicone rubber baffle material lasts a good long while and has a broad temperature range. I've never had to replace it like regular rubber baffles. Also the aforementioned UHMW tape helps prevent any wear to the baffle and cowl.

*When choosing the tape thickness, thinner (about .006" thick) is easier to work with and will conform to follow simple corners. If you go with thicker, say .010" or so tape, it won't make tight bends so easily. The tape is so strong it will not stretch (at all) to conform to compound curves, so you have to snip with scissors and fill in with pieces as required- easy to do.

Look for tape with acrylic adhesive, remove all oil from surface, apply at room temperature or warmer (or gently warm surfaces)

Unless Aviat has changed the way the front lower baffle contacts cowl, you may need to make a rigid lip to "capture" the edge of the baffle to keep it sealed. I used aluminum strips, crimping it to follow the curvature and then gluing it in place.

I posted pics of all this here years ago, not sure if they went away with Photobucket.

 

[belloypilot]

Great information. Thanks. We’re doing and engine installation in the Bonanza now and we’ll get some of that tape. I’m hoping to install the McFarlane baffle seal product in the Husky in late January and will do the same then.

 

[bumper]

Great information. Thanks. We’re doing and engine installation in the Bonanza now and we’ll get some of that tape. I’m hoping to install the McFarlane baffle seal product in the Husky in late January and will do the same then.

I think you'll like that tape, it has all manner of uses, from building up a worn pivot pin (assuming low speed, such as adjustable cowl flap hinge pin etc). It is excellent for anti-chafe tape between front cowl overlaps (just be sure to remove all old stuff and adhesive).