Bob Turner
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Anybody know if Bellanca got approval for T-88 when they were doing wood spars? I heard that at least one mfgr got approval . . .
8KCAB Glue?
- Thread starter Bob Turner
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Not that I could find out in my research in the past. Resorcinol is the only approved glue I could find any resource on.
I have a friend that was an engineer with the FAA, who has experience with composites. I brought it up with him and his only concern was that epoxy loses its strength as its heated. Think dark wing sitting out in the Arizona sun! But, its then "heat treated" to that temp. Problem with T-88 is that it has not been tested as such, so there is no data.
When I used to work on Diamond aircraft, we would have to bake any repairs or reinforcements made to the plane to increase its temp strength. As such, the only authorized color to paint the plane is white, and even still, there is a temperature indicator in the cockpit that was part of the pre-flight, for the plane was grounded if the temp was too high.
I have a friend that was an engineer with the FAA, who has experience with composites. I brought it up with him and his only concern was that epoxy loses its strength as its heated. Think dark wing sitting out in the Arizona sun! But, its then "heat treated" to that temp. Problem with T-88 is that it has not been tested as such, so there is no data.
When I used to work on Diamond aircraft, we would have to bake any repairs or reinforcements made to the plane to increase its temp strength. As such, the only authorized color to paint the plane is white, and even still, there is a temperature indicator in the cockpit that was part of the pre-flight, for the plane was grounded if the temp was too high.
Bob Turner
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43.13 says unless otherwise specified by the certificate holder, Resorcinol. Problem for me is the manufacturer says Casein, and 43.13 explicitly says that trumps the data in the AC.
Contacted the folks who make T-88. They are not at all interested in supporting any kind of field approval.
It is all moot now - the spar crack was almost six feet long. Easier to replace the whole darn thing. I have over half the old spar out. Interesting exercise!
Contacted the folks who make T-88. They are not at all interested in supporting any kind of field approval.
It is all moot now - the spar crack was almost six feet long. Easier to replace the whole darn thing. I have over half the old spar out. Interesting exercise!
Bob Turner
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The Stearman manual is not so generous. Turns out I do not care - I have to replace the entire spar. Minor rib repairs will be done with Casein.
The T-88 would be far better, but the ribs are pretty strong in any case. A glue joint failure in the few minor repairs I have to do would not be noticeable.
The T-88 would be far better, but the ribs are pretty strong in any case. A glue joint failure in the few minor repairs I have to do would not be noticeable.