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-   -   Photos: Really good baffle seals (https://vansairforce.net/community/showthread.php?t=141528)

AlexPeterson 10-27-2016 06:27 AM

Quote:

Originally Posted by Marc Bourget (Post 1122162)

Do you have any data? Does your "full pressure" mean the dynamic pressure at the speed you were measuring?

mjb

Marc, yes, based on speed, temp, altitude, etc., it was very nearly full recovery. The data is probably in a stack of stuff in a safe place... It might even be somewhere in these forums, but I don't recall.

AlexPeterson 10-27-2016 06:29 AM

Quote:

Originally Posted by rv8ch (Post 1122155)
Thanks Alex, those are probably the most clear pictures of the way to do the baffles around the inlet that I've seen, and clear up a lot for me.

Mickey, I'm glad it helps. I just couldn't see putting a square peg in a round hole:eek: I don't recall how the plans said to deal (or not) with that area. I think I just used some .016" aluminum to make that fillet.

rvsxer 10-27-2016 09:41 AM

Alex, I agree. Those are very good pictures. I just changed all my forward baffling from "seal on the cowl" to "seal on the ramps". I remember asking Van's which way to go (wayyyy back when...) and they said either way will work. I also extended the lower cowl seal way up the sides. They didn't even go out past the "curve". Now everything looks like yours. I don't have a lot of time on the mod but it looks like CHT's 10-12 degrees lower and oil temp 5-10.

Marc Bourget 10-27-2016 10:31 AM

Quote:

Originally Posted by AlexPeterson (Post 1122177)
Marc, yes, based on speed, temp, altitude, etc., it was very nearly full recovery. The data is probably in a stack of stuff in a safe place... It might even be somewhere in these forums, but I don't recall.

Alex, I am very interested in the data, but it's not something I need right now.

I understand from Zavatson that 60% is pretty good, but "very nearly full" would seem to be greater.

Next, where can I view photos of your efforts?

TIA

mjb

f14av8r 10-27-2016 02:11 PM

Big Curves
 
Hi Guys,
I have a question. I'm reworking my seals and need some advice. What size material should I use when working the curvy sections around the spinner and the back of baffled area. Should I just bend the **** out of 3" wide material or should I be using something wider?

crabandy 10-27-2016 07:23 PM

Quote:

Originally Posted by f14av8r (Post 1122305)
Hi Guys,
I have a question. I'm reworking my seals and need some advice. What size material should I use when working the curvy sections around the spinner and the back of baffled area. Should I just bend the **** out of 3" wide material or should I be using something wider?

I wish I would've used a larger 1 piece around the curvy sections, instead I ended up using lots of short sections like most do to conform to the curves but leak at the overlaps.
Next time I would use a sheet of cheap vinyl or similar to mimic the baffle seal as I cut/trimmed and pieced together a pattern to make a 1 piece seal. The resulting pattern will tell you what size material you need. In the end I think it's faster and easier to make a 1 piece pattern to cut a finished piece of baffling than to fit lots of little pieces, not to mention a better seal. Just a theory but an easy one to try.....

Dreamin9 01-18-2017 02:16 PM

From reviewing this thread it would appear my front/middle baffle seal is pointing the wrong way. It's edge is tucked under(behind) the wrap around portion of the top cowl. I thought maybe the pressure inside would be higher than the pressure behind the gear and keep the seal tight?

Or, does this seal need to be angled backwards for better seal? If so, does the seal where it curves backward need to be redone?

PS This RV-9A is new to me and runs hot.

Hope the picture compensates for my poor description.



Looks like I haven't figure out picture posting, maybe the following will help.

http://tinypic.com/m/jike8x/3

YellowJacket RV9 01-18-2017 02:42 PM

Definitely should be the other way around. I'm guessing if you reverse them it will help with your cooling issues, but would also guess that there may be other baffling problems too. Worth going over and making sure every possible place is sealed.

Chris

BillL 01-18-2017 07:51 PM

Quote:

Originally Posted by Dreamin9 (Post 1142966)
Hope the picture compensates for my poor description.



Looks like I haven't figure out picture posting, maybe the following will help.

http://tinypic.com/m/jike8x/3


DanH 01-18-2017 08:11 PM

Quote:

Originally Posted by Dreamin9 (Post 1142966)
From reviewing this thread it would appear my front/middle baffle seal is pointing the wrong way.

Yep, bass ackwards for sure.


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