Rear spar reinforcement plates

Howdy,

After years of lurking I've decided I need to jump in and ask a question and it goes like this:

I am assembling the rear spars on my slow build -9. There are two reinforcement plates that are match drilled to the spar where the flap and aileron hinges attach. Does the spar flange and the flanges of these plates need to be dimpled before they are assembled so the wing skin rivets can sit in them later? The plans don't mention it when describing the assembly of them.

Thanks,

Matt
Sloow build RV-9
Sheffield, UK

Part Numbers?

Matt,

Not sure which parts you're talking about. Do you mean W-925B? Give me some part numbers and I'll let you know. I finished my left wing a month ago.

Tom

Yes. If the 9 spar is anything like the 7's I'm familiar with, also dimple the spar above reinforcement plates at the root before installing them. This should be in the narrative instructions.

John Siebold

I think they are W-907D and W-907E.

Thanks,

Matt

RV7ator said:

Yes. If the 9 spar is anything like the 7's I'm familiar with, also dimple the spar above reinforcement plates at the root before installing them. This should be in the narrative instructions.

John Siebold

Click to expand...

Thanks. The plans are explicit about dimpling the spar flange at the innermost end above the doubler plates but don't mention the other locations, hence the question.

Thanks,

Matt.

Double plates

Matt,

Those doubler plates have one flange each. They should be dimpled before assembly with the spar, and will nest into the spar flange dimples. Doesn't matter whether you dimple the spar flange or the doubler plate flange first, just do them both before assembly.

Hope that helps.

Tom

Thanks fellas.

This confirms what I had thought but I wanted to make sure that was the case before I dimpled the flanges.

As I move through the build I am slowly getting used to the plans being less explicit about every task and leaving more to the builder. It's the process of building up your own confidence and feel for what is right.

Cheers,

Matt.