Baffle Seal Pirep

[Davidv]

Just wanted to give a quick pirep on my new baffles from @GEE-BEE.  Overall I’m very happy, previously my hottest cylinder ROP was about 391 down low and it was tough to keep them under 400 up high.  After the new baffles nothing is over 375 below 7,500.  I took it up to 17.5K on Friday and was able to keep all cylinders between 370 and 389 with cowl flaps closed. 

To my surprise, every piece in the kit matched my original baffles (even though some were in such rough shape it was tough).  I had nightmares of an IKEA like experience with one missing piece at the end. However, this was probably easier since I had original baffling.  Phil Jiminez was nice enough to do it while I waited and only charged an extra $10/hr for watching and asking questions (kidding).  

Even though Phil and Mike did all of the work the tip I would give is to fold the top baffling forward before you connect the top pieces.  It seems to be very well sealed in my cowling except for some small waves at the top that I can see through the front when the cowl it on.  We will have to address at some point. 

I’ve attached a picture below when it was about 90 percent done (still had to screw sections together)

[DonMuncy]

1 hour ago, Davidv said:

 

It seems to be very well sealed in my cowling except for some small waves at the top that I can see through the front when the cowl it on.  

In my hangar elf's experience, this is inevitable. Each "wave" can be slit longitudinally (along the axis of the plane.) This allows the baffle to overlap itself and make a good seal. Easily confirmed as you have learned, by looking in the front.

[ArtVandelay]

As you run it, the baffling might break in and lose some stiffness. This is what mine looked like after a couple of flights:




Tom

[PT20J]

Not surprised they fit well. Guy die cuts them and makes his dies from originals he has obtained over time. 

If gaps are small and temps OK I wouldn’t worry too much as air pressure likely closes them during flight.

Key to a good fit is stretching the material slightly during installation to get it to “lean” forward and inward. Even so, small gaps are, as Don says, inevitable.

Skip

 

[Davidv]

Thanks @ArtVandelay looks great.  And it wasn’t until just now that I realized how great your screen name is :).

[PT20J]

1 minute ago, ArtVandelay said:

As you run it, the baffling might break in and lose some stiffness. This is what mine looked like after a couple of flights:

Maybe, but on my J, they fit perfectly after installation and then got a couple of small puckers after a few hours.  So, I guess it could go either way.

Skip

[ArtVandelay]

5 minutes ago, PT20J said:

Maybe, but on my J, they fit perfectly after installation and then got a couple of small puckers after a few hours.  So, I guess it could go either way.

Skip

I did say “might”. ;-)  I have more overlapping then David does, so it seemed to help. I still have to be careful reinstalling cowl to prevent puckering after 35 hours.