Baffle Rub Strip

JDH · Post by **JDH** » Thu May 08, 2003 3:13 pm

The baffle rub strips on my '52 are very rough and in need of replacement. Over the years, felt and other type of materials have been fastened to the baffles and I want to replace it all with something that will look better and do a better job. Original part number example: 0450234-25 rear baffle rub strip. Could P/N 05-00663 on page 125 of Aircraft Spruce catalogue be used? Or something like it? And, once I find this product, hopefully by the foot, what is the best way to fasten it? Staples (as original) or glue or rivet??
Thanks for any help. JD

Post by **GAHorn** » Thu May 08, 2003 7:43 pm

That Spruce PN 05-00663 is listed as a "chafe" seal, not a baffle seal. I've called Spruce and had them pull some off the shelf and describe it to me. I'm afraid it's too thin/flimsy to perform well as a cowl/baffle seal. My own airplane has a high-temp red silicone "P" shaped product that is actually a Fokker thrust-reverser seal. Sorry, no part number.
Brown Aircraft Supply sells thru AVIALL (800-284-2551) (800 AVIALL 1) their "Cowl Vent Seal", pn VS6491, which is similar if not identical to the original Cessna product. It is a "P" shaped black neoprene impregnated cloth sewn around a felt core, measuring 5/16" X 1-7/8", usually installed with rivets or staples. (Heavy safety-wire will approximate staples.)
What is more commonly used these days on production aircraft, as well as for replacement purposes, is Spruce PN 05-00775, a red silicone seal that is 3/32" thick X 9 ft long and 3" wide. It is usually riveted on using pop-rivets and flat washers. It's pretty durable, and makes an excellent cooling seal because it will fold forward against the breeze and so will seal up against the cowling very nicely. It sells for $19.85 and is all you'll need to do the entire engine compartment.

Walker · Post by **Walker** » Wed Feb 16, 2005 8:02 pm

I am working on putting in the "P" seal I bought from Brown in a 1952 model. They called it Tadpole. The IPC is not clear on which side of the rear baffle to put it on. I put it on first with the "tail" of the tadpole on the back side as that made sense with the old staple holes. As I looked at it and played with it, it seemed to be wrong as the cowl pressure can push it out. To put on the inside and use the old holes makes the tail too short. I have no reference as the last person really made a mess with all kinds of stuff jammed in there. It appears that the P seal should sit on the top flange of the baffle to make up the space between the cover and rear baffle. It is possible that the Brown Tadpole is not suitable for this application.A picture of proper installation would be greatly appreciated.

Post by **GAHorn** » Thu Feb 17, 2005 4:23 pm

The Brown Aircraft Supply VS6491 is now a black EPDM "tadpole" with a red-silicone type filler in the "bulb". http://www.brownaircraft.com or 904-396-6655

HA · Post by HA » Thu Feb 17, 2005 5:57 pm

I replaced all my baffling with RAM orange silicone stuff, like we use on all our twins. I used rivets, mounted the seal on the inside (engine side) of the aluminum baffles and worked it so it leans forward. That means that the airflow will push it up against the inside of the cowling, whole idea being to make the air go through the cylinder fins and out the bottom of the cowl.

I used plain soft aluminum (MS20470A-4) rivets, you could use pop rivets too since it's not structure.

Along with repairing the intercylinder baffle pieces and liberal use of hi-temp orange RTV silicone sealer, my CHT dropped nicely (sorry, didn't note how much but it made me happy)