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RV-10 Forest of Tabs Ground Location

bwestfall

Well Known Member
I'm looking for pic's of people's grounding block installation for placement. Facing the firewall somewhere between the center and left ribs. I'm just wondering if anyone ran in to a gotcha in that location anywhere?

Bob L. I sorta could see a pic on your kitlog site but it was small and somewhat hard to see.

THX
 
SUNP0010.jpg
 
That's a great location but that's where I have my righthand VP200 box mounted (the other is mirrored on the left side). On my RV-6A, it's on one of the firewall weldments. As the first photo shows, it doesn't need to be on the firewall, and orientation is not vital either. When I was building the -6A, I just kept it clamped in an approximate location while I was doing my testing and didn't finalize it until everything else had been set. It's like working in the engine compartment: some things have a required location, so do them first and then fit the other things around them.
 
I was thinking of mounting it vertical so as not to have to secure it via the middle screw hole (just another firewall hole). No big deal though I guess and I suppose it gives you another easy place to run a ground wire under the cowl. Those are few and typically easy to find a spot on the engine case if needed.
 
Gotcha

The entire front bay is a Gotcha location for anything other than stuff you absolutely don't ever have to touch again after the panel is installed.
Unless you install access panels, in which case you can disregard my post.
Why not mount them on the second bulkhead facing the pilot?
Having them here allows you to do most of the wiring in an upright position while sitting on the seat. Once the panel is installed you can easily access it by removing an EFIS.
Anything mounted higher than the horizontal brace on the firewall will force you to work upside down with your head bumping up against the rudder pedals and in a most awkward position trying to reach a spade connector or what have you. Of course its easy while the cover is still off.
Here is what worked for me.

IMG_0611.JPG
 
Do you run a direct ground wife from the engine to the tabs in the forward bay? How are you connecting an engine ground?
 
The aircraft is metal and conductivity is uninterrupted from the firewall.
The RV10 engine mount has 2 tabs welded on for ground straps. I also have a ground strap directly from the firewall.
The direct ground strap to forest of grounding tabs has been debated elsewhere but is just not necessary in an all metal aircraft.
Several postings of ground tabs on the second bulkhead are all working out just fine. One more thing while we are on the subject of "Gotcha" in the front bay. I used nut plates for every conceivable mounting configuration, because it is even difficult to reach behind the second bulkhead once the panel is installed.
All those adel clamps that you see for wire routing have nut plates and allow you to use a large size adel to string wires and when you are done you can easily remove them and install the correct size.
 
Do you run a direct ground wife from the engine to the tabs in the forward bay? How are you connecting an engine ground?

I'm running one up to the firewall and then jumping from the firewall directly to the engine case with a short jumper of #2 wire. To provide a secondary ground, I'm going putting a regular ground strap between the engine case and one of the tabs on the motor mount.

I'm also putting smaller tabs in each wing-tip, under the seats, and one in the tail. Each of those will be grounded back to the tabs on FW.

I realize it's overkill, but I've spent too much time chasing down phantom ground problems when relying on the structure itself to provide a reliable path to the battery. I decided to fix it now, before I get cross-eyed ****** off on the ramp one hot August afternoon in Texas.
 
Ernst and Mike, I see that you guys have angle running forward from the lower panel to the subpanel. Unless I have missed something (and I could have, haven't finalized this section yet), this isn't in the plans. Is the idea to provide support for wire bundles, or to add some stiffness?
 
Ernst and Mike, I see that you guys have angle running forward from the lower panel to the subpanel. Unless I have missed something (and I could have, haven't finalized this section yet), this isn't in the plans. Is the idea to provide support for wire bundles, or to add some stiffness?

I did it to provide a place for the wire bundles.

There is one on the other side of the radio stack as well.
 
Thanks for the posts I hadn't considered the upside time w/firewall placement. Lord knows I should remember because I've spent hours crammed under the panel when I replaced the radio stack on my 152 about 2 years ago. Maybe it's one of those things where you block out the "bad memories".

Now that the AFS screens are so shallow I've got a ton more room in second bulkhead area. I'll likely move my ground block up to this area as it makes sense.

I really like the nutplate idea for all fastners too great idea. It would seem all the work reloacting to this position would be for not if you had to reach up to fasten a nut every time you worked on things.

Great ideas guys!!
 
I'm with you Phil, I ran ground blocks on the wingtips and the tail with grounds all originated from the negative on the battery. I didn't want any noise from loop from the aircraft structure. Like you said probably overkill but I hate whining:). LED's for strobes too.
 
Grounding tabs

Back-to-back grounding tabs on both sides of the firewall is a common practice and is what I did. If you plan on dual electrical systems with dual alternators be sure to allow room aft of where the pad mounted alternator sits. The SkyTec pad mounted alternator is larger than you think. Keep the firewall clear directly behind where the alternator sits, i.e. don't put the grounding tabs there.
 
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