Baffling

[saddler]

I am to the point where I need to trim the baffles and add the baffle seal. My question is if you had to do it over again, would you use the black seal that comes with the Sonex fence baffle kit or would you use something like you see on certified airplanes such as the red silicone seal like this?

https://www.aircraftspruce.com/catalog/ ... lseals.php

[kmacht]

I went with the silicone seal similar to the one in the link you posted. I tried and struggled with the p-seal from Sonex for 3 weekends before giving up. WIth the P seal it has to be trimmed and installed pretty close to perfect in order to get a good seal. If it is too tall and squishing against the top of the cowl it is very hard to install the cowl (especially if you do the horizontal split mod). There isn't a whole lot of give in the P section to squish down. If it is too short or not pressing hard enough against the cowl you will have air that leaks around it and get less efficient cooling. WIth the red silicone seal you intentionally make the seal taller than the opening. This makes it so the seal folds over and inward towards the engine when you install the cowl. The harder the air blows against it the tighter the seal gets to the cowl. It took me less than a day to get the silicone seal trimmed and installed once I pulled off the p-seal that came with my aerovee. So far after 25 hours of flight testing I have yet to get anywhere near the redline limits for CHT's. If anything they have been a bit too cool.

Keith
#554

[SonexN76ET]

I agree with Keith. I say definitely go with the silicone baffle material like you show in your link. I spent countless hours trying to adjust my baffles with the stock material. I recently redid mine with silicone and am very pleased so far. You also don't have to be as precise lining the metal baffles up with the cowling.

Jake

[avee8r]

I used the black seal supplied with the kit. It works fine for me.
Again, patience and persistence will pay off in the end.
Happy Landings
John
N50NX

[dtwolcott]

I too am having a problem with getting the cowl to fit with the p seal. Those of you that have used the silicone baffle material what size did you use? ie
1/8 by 2", 3" or what size worked best.
Don

[SonexN76ET]

I used the 3/32 by 3 inch silicone baffle material and trimmed it down. I got the black one. I also used it as the ends of my gear leg failings and on the cross strap where the cowling attaches forward the windscreen. Great stuff!

Jake