Description
Page 8-2 of the RV7 assembly manual tells the builder to fabricate a set of 1 7/16 (1.4375) spacers to properly space the parts of F704 center section so that the Wing spar can fit inside.
If this space is too small, you will have a very difficult time installing the wing. It may also result in galled or scratched mating surfaces, undesirable in a highly stressed structural component. The defects are not visible after installation. That said, I know of no history of RV7 wing failures due to wing installation or spar root failure, and do not mean to imply there is a problem.
Most spar stubs I have measured are greater than 1.438 thick. It just makes sense to provide a space for the wing root to go in that is not smaller than the wing root itself.
We recommend that you clamp the pieces of your wing root together and measure it with an accurate calipers or micrometer. Select spacers that are no less than this measurement to no more than about .003″ greater.
Our spar spacer set is a matched (+/- .001) set of steel tubes that have parallel ends.
They have an inside diameter of .438 and an OD of .750.
While we make these in a range from 1.438 to 1.447. When a size is selected it will tell you if these are in stock. If they are not in stock select the next highest value.
