Workflow Choreography : Before or after Engine hang?

What has to be done fuselage wise before hanging the engine?

I'm thinking it would be very desirable to have the forward top skin off, to work on hanging stuff from the firewall and passthroughs, but that skin must be providing a lot of stability as well as lock in the geometry. And I would like to have the engine weight and load on the front before finalizing the fit of the forward baggage door.

Is it Ok to hang the engine with the Forward Top Skin not riveted yet?


I'm thinking similar to working on the canopy. The engine likely will create some flexion in the fuselage, should I wait until the engine is mounted before canopy work?


RV8 in this case, though I imagine the quest holds for any.
Thanks

JW

I've got an RV-7 with a tip-up canopy, so it may be different in this regard than the RV-8. My landing gear and engine were mounted the same day, with the forward top skin not being mounted until much later. The canopy was fitted with the forward top skin held in place with clecoes. The skin did stiffen things up significantly after being riveted in place, but it didn't really affect the fit of the canopy. The skin wasn't riveted in place until almost all of the wiring was done, and I had to make sure I left room for bucking bar access.

Never ending debate topic but if you put it in after you install the top you know you can get to it to maintain it. You have decent access to the area behind the firewall with the baggage floor and door removed. You have the canopy windscreen front fairing to deal with and doing that with the engine in place makes even less sense to me. Waiting to fit the baggage door at the end with the cowl on might not be a bad idea.

I wouldn't work the canopy or fiberglass with the engine in place, but that's just my worthless opinion. That dust goes everywhere. I did all that first. Canopy, windshield, trim, top skin, firewall, etc all riveted. Yes, it was a pain to route stuff, but I've done worse. I do recommend using nutplates where ever possible FWF, so stuff attaches from the forward side without requiring a second person. That way you can leave it off and it's out of the way. I hated that Vans had all that stuff attached with bolts and nuts. Some of it, I retro-fitted nutplates.

My RV-3B has a removable forward top skin (as do RV-4s and RV-6s) and since the screws always go in with no alignment problem, and the engine is on, I expect that you could hang the engine without messing anything up.

Caveat, the -3B is a lot narrower , thus stiffer, and with an O-320, probably has a lighter engine than your plane.

Dave