Aluminum alloy and thickness for engine baffle repair?

[Cooper]

I attended one of the Cessna 170 forums at Sun-n-Fun on Thrusday, April 15th, 2004 in Lakeland. Dale Faux was the moderator. I wanted to know what thickness and what aluminum allow (1100, 3003, 5052, etc) should I use to repair and or replace the engine baffling on my 1953 Cessna 170.

Dale suggested that George Horn would know. At any rate, I thought it would be better to post the entry here so that other members would have the information.

[derf62]

I also sat in the same seminar. I have completed a few repairs and have found that 3003 H14 (.032) seems to work pretty good. Its soft enough to make critical bends like the one's over the top of the cylinders that require a 180 degree bend. Sure takes a bit of time to make them presentable.

[blueldr]

I made most of my baffling with 2024 T3, .032, but you must use the proper setback on the brake when bending it
The inner cylinder baffles were made of 2024 T3, .025.
Actually, it is non structural so I guess you could use any material.

[GAHorn]

The "Official" (original) baffles are made of 1100 Alum. alloy, H-14, thickness .032.
Regards,
George Horn
Parts/Mx

[Cooper]

Since the original was 1100 H-14 .032", is there any reason to use anything else. For example, is 1100 H-14 .032" better than 2024T3 for the cylinder baffles?

I have heard that 2024T3 is more prone to cracking under vibration than the softer aluminum. I am also assuming that the 1100 H-14 is softer than 2024 T3.

While I am at it on the baffles, what is a good material to use to seal the baffles to the cowling?

[GAHorn]

Spruce (and others) sell silicone-based baffle seal material in 3" width's and 9' lengths. It does well.
If you want the more original type "P" seal, let me know, and when I get back from this trip, I'll try to find a source for you.