Baffle material and outside corners..how?

David_Nelson · #1 06-27-2009, 07:04 PM

Hi All,

I'm fitting/trimming the baffle material so that I can get the baffles squared away..mostly.

Anyways, I can't figure out how to trim and place the baffle material on an outside corner so that it seals against the cowling. This is the outside corner that I'm talking about:

I know there's supposed to some sheet-metal here that would make this easy but I'm going a different route by adding a support strut and mounting the oil cooler as high as reasonably possible.

Thanks!

L.Adamson · #2 06-27-2009, 08:02 PM

This is how I did it. The rivited pieces can also be sewn together. Some builders attach a straight piece across the top to attach the baffles to. You should be able to find some websites that show this.

L.Adamson --- RV6A (flying)

49clipper · #3 06-27-2009, 08:10 PM

Be aware of those exposed rivets in the baffling. I have seen way too many times when those rubbed a hole in aluminum cowlings.

David_Nelson · #4 06-27-2009, 08:35 PM

Aha! Isn't that clever. I'll be sure to sew mine.

Thanks Guys!

/\/elson

N130WN · #5 06-27-2009, 09:46 PM

You can fill in the joggle in that corner. I have some notes related to that corner of the baffling and additional oil cooler support here:

http://blog.bowenaero.com/?p=392

Rick6a · #6 06-28-2009, 08:37 AM

Another way to approach the problem is to overlap the two pieces of baffle seal at the outside corner in such a way as to leave plenty of material on each piece to firmly bind them together with high temp RTV.

Ted RV8 · #7 06-28-2009, 08:51 AM

I overlapped them as Rick shows and then tied them with lacing, loosely.

I wanted them to find their own best position once in operation with the air pressure against them. After running a few times they settle into position and giving the best seal.

If you RTV them together and it happens to be the wrong position for best seal they will always be in that position.

Wouldn't rivet them as the rivet will always be rubbing on the fiberglass cowl. Eventually it will do damege to the cowl.

Ted

Rockyjs · #8 06-28-2009, 10:04 AM

There is also a strengthener piece that comes with the newer baffle kit that makes this a straight shot across the back. It can be ordered separately.

David_Nelson · #9 06-28-2009, 09:19 PM

Thanks again guys for the help. I managed to get the rubber baffles about 99% done. Just lacking the inlet ramps, some sewing, and of course some riveting.

Rick - Curious as to why you didn't silicone the rest of the corners? The one corner seems to have come out very nicely.

Ted - I was wondering what to use for "thread". I take it you haven't had any problems with lacing and high temps. Correct? I find it odd that AC 43.13 doesn't include a section on "cooling".

Rockyjs - My kit did come with that part. I've decided to do away with it for two reasons: 1) I plan to install a strut from that corner over to one of the case bolts along the centerline of the engine. This has proven to work very well against cracking of the aft left corner for other builders. 2) I want to maximize the height of the cooler in order to maximize the number of cooling fins that are subjected to cooling air. Seems that with the bracket, I'd have to install the cooler lower and share the air with the #4 cylinder fins. There was also discussion on VAF and from I recall the recommendation was to install the cooler as high as possible. The plans also indicate to the same.

/\/elson

Brantel · #10 06-29-2009, 05:04 AM

Quote:

Originally Posted by David_Nelson

Rockyjs - My kit did come with that part. I've decided to do away with it for two reasons: 1) I plan to install a strut from that corner over to one of the case bolts along the centerline of the engine. This has proven to work very well against cracking of the aft left corner for other builders. 2) I want to maximize the height of the cooler in order to maximize the number of cooling fins that are subjected to cooling air. Seems that with the bracket, I'd have to install the cooler lower and share the air with the #4 cylinder fins. There was also discussion on VAF and from I recall the recommendation was to install the cooler as high as possible. The plans also indicate to the same.
/\/elson

You have to be carefull with the cooler much higher than what you can get with that new part Van is now including, the cooler will run into the cowl and could also have problems with the engine mount.

You could still add the brace bar in addition to this part.