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humptybump

Well Known Member
I'm in the process of drilling out the rivets in the passenger floor section of my RV-8. I need to add "stuff" to the back. I never want to do this again.

I'm looking for recommendations for light weight options to add a "chase" from front to back before I rivet the floor back down.
 
humptybump said:
I'm in the process of drilling out the rivets in the passenger floor section of my RV-8. I need to add "stuff" to the back. I never want to do this again.

I'm looking for recommendations for light weight options to add a "chase" from front to back before I rivet the floor back down.
Click to expand...

1" (3/4"ID) plastic irrigation pipe works well.
 
The idea of nut plates is nice but that's a lot of nut plates. If I were building and had all the tools and the necessary scraps of material etc, I'd condider looking at laying out one side to be removable. Then again, if I were building I wouldn't be retrofitting an autopilot then retrofitting an ADSB antenna and a remote magnetic sensor :)

Based on what I can get access to within the floor, it looks like I can manage the 2 or 3 holes for a plastic conduit pipe. I just need to find a source for the pipe.

Any other light weight tubing options that come to mind ?
 
humptybump said:
I'm in the process of drilling out the rivets in the passenger floor section of my RV-8. I need to add "stuff" to the back. I never want to do this again.

I'm looking for recommendations for light weight options to add a "chase" from front to back before I rivet the floor back down.
Click to expand...

When I took the EAA worshop for electronics, the instructor recommended using light weight (thin wall) pvc pipe as a conduit. You should be able to clamp down a 1" or 1.5" piece the the length you need. Leave an extra length of string in it for pulling through future stuff.

-John
 
Glen, where in VA are you? I have some corrugated conduit if you need a piece. Best thing to do is run it under the floor and keep a string through it. Should you ever need to pull wires through it again in the future that will make it very simple.
 
DaAV8R said:
Has anyone installed the floor with tinnermans?
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When I built my -8 I used Van's corrugated wing conduit for the floor, both for front/aft and side/side runs.

For my baggage floor I used self-locking clip nuts. I got a good deal on a lot at Sun & Fun. The clip nuts are much easier to install than rivets, let alone nutplates. (I used nutplates for the main cabin floors, which were a real PIA to install).
 
I bit the bullet and used nut plates for the rear baggage compartment floor so it is removable. I will use pop rivets for the floors except for the rear row of holes which are shared with the baggage compartment floor. These are nut plated. I will use the Van's conduit for under the floors. I used this in the wings and tail cone and can easily fish wires through. You can also use blue conduit connectors to join 2 pieces of conduit together. They snap onto the grooves in the conduit. I cut a window in the connectors on one side with a Dremmel tool to allow wire to exit in intermediate positions. I bought the connectors at Home Depot in the electrical department. Under $1.
 
Glen, go to Lowes or Home Depot and get a length of Poly pipe. Very lightweight, rigid enough, and smooth!
 
I mentioned this in another thread but my Comanche has hundreds of sheet metal screws in it with just a hole drilled and nothing else. Most of them have been there for exactly 50 years. In places that come apart often, such as inspection panels, they used nutplates or tinnermans. But for a floor that rarely comes apart I don't see anything wrong with this approach.
 
Hi Bob. I remember reading it and thinking that will work pretty well ... until my next condition inspection when the A&P gives me a funny look. He is great and is happy to check my work in between the condition inspections. He is also on the conservative side which has served me well.

I have enough of the rear floor open now that I can install a section of light weight pipe (which I found today).

I will keep all the other good suggestions in my back pocket (since my wallet isn't taking up much space these days).
 
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I wouldn't recommend Tinnerman's for the floor.

DaAV8R said:
Has anyone installed the floor with tinnermans?
Click to expand...

The floors are actually structural. Yes, they add significant torsional stiffness to the open fuselage section for the cockpit. Open sections have very little torsional stiffness, and every bit helps. Some comes from the cabin cross brace, some from the roll-bar, and some from the floors. Some even from the canopy rails.

Tinnerman's would allow some slop, within the clearance hole fit of each screw hole. It would allow the structure to work. probably ok, but not ideal.

If you use regular plate-nuts and screws, you can use every other rivet hole, no need to use every hole.
 
Nutplates on mine and since they are complete and done I like it a lot. I can tell you though, during the several days of drilling and mounting nutplates...I may have used Charlie Kuss's name in vain a few times for suggesting it. One thing that made the job far easier was a set of parallel jaw pliers to squeeze the rivets. Far easier to get in there than my pneumatic squeezer. Those pliers have been one of my favorite tools since Gringo showed them to me. If you go through the bother of nutplates, you won't regret it afterwards and you can put quite a bit of stuff under those floors if still building or in future panel upgrades.
 
I "made the call" ... attempting to install nut plates in a finished RV-8 was not going to happen unless I spent the next 6 weeks in yoga classes. I opted to install a poly-pipe thru the affected area. I am moving some cable routing to the new chase. I am happy with the trade off.
 
It's too late for you, but it is not too difficult to add a conduit under the floor without taking up the floor.
Just cut your hole through the bulkhead at each end. Might need an angle drill or flex drive.
Clean your holes.
Vacuum out with a piece of 3/4" clear tubing taped to vac hose.
Fish a length of piano wire through both holes.
Thread the conduit through the holes on the piano wire, starting at the front to make it easier, as the front bulkhead is way back under the floor.
I used that black ribbed conduit from Van's, but smooth hose of some kind might be better. Needs to be flexible.

A few 4 letter words seemed to help.
 
jimgreen said:
it is not too difficult to add a conduit under the floor without taking up the floor.
Click to expand...

I thought about that but to get the the aft bulkhead you need at least a 12" extension. You also need to be careful with trying to "drill blind" as you do not want to get near the reinforcement at 807 where the rear of the wing mounts.
 
ColoRv said:
One thing that made the job far easier was a set of parallel jaw pliers to squeeze the rivets. Far easier to get in there than my pneumatic squeezer.
Click to expand...

I've used those pliers for other things, but would never have thought of using them for rivets. Unfortunately I don't own any. What size are you using? I might buy myself a treat for Christmas ...
 
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