Garmin G3X mounting flange

[arborite]

I’ve cut the big hole in the panel for the G3X display and am now thinking about the best way to mount the supplied flange. For those of you who have done this, did you rivet/bond the flange to the back side of the panel (improved stiffness, eliminate potential rattle) or did you make it more easily removable (easier replacement of anchor nuts, future flexibility). I’m leaning toward a more permanent attachment. also will be adding stiffeners to the back side of the panel to reduce flex since i’m mounting the ADAHRS unit on the back of the display.

Any words of wisdom from those who have done this?

Thanks

Wayne
IMG_0972.jpg

[jaredyates]

For the Dynon units I riveted the reinforcements. Figuring if I needed to resize for a different screen later, I'd be willing to cut a whole new panel if necessary.

[gregc]

I had vibration issues with the Garmin ADAHRS so I would go with the stiffer solution. Also anchor the ADAHRS wiring and pitot static lines well.

[arborite]

Thanks gents. I’m making the reinforcements today and will rivet/bond the whole thing to the panel for stiffness. trying to keep it as light as possible but needs to be stiff as you say for ADAHRS performance.

[rodsmith]

Thanks gents. I’m making the reinforcements today and will rivet/bond the whole thing to the panel for stiffness. trying to keep it as light as possible but needs to be stiff as you say for ADAHRS performance.

I think that is the way to go. I riveted the corners to the panel using the pre-punched holes. Did not secure it otherwise, but my ADHRS is mounted to the frame not the back of the screen.

[Lee]

Current plan is to anodize my panel black. Mcmaster Carr has black flat head screew that I will use to mount all the trays. They should largely disappear.

Lee

[arborite]

Current plan is to anodize my panel black. Mcmaster Carr has black flat head screew that I will use to mount all the trays. They should largely disappear.

Lee

That will be really nice. will you etch the lettering in the anodization?

[500AGL]

I’d like to pass along a few tidbits related to this.

- Garmin actually specifies a .090” panel for installation. This is largely unheard of in the experimental world, but the standard in the certified world. So just understand that they are looking for some rigidity for their instruments.

- When using a panel of 080-090 you can tap the panel for mounting screws, although using single leg nut plates is the common install method. I never use the Garmin backing plate for install. While it may have some small value on thin panels (030-050) I’d rather see one use a thicker overlay if desired.

- While Garmin created a mounting location for the GSU25 on the back of the G3, it’s not a great location unless it’s the only space available. In addition to vibration potential, the biggest issue to access to behind the panel.
The G3 when mounted by itself allows great access via 4 screws, two plugs and a coax disconnect.
If the GSU is mounted there you have pitot static and aoa lines attached as well as the two GSU connectors.
you can either disconnect the lines from the GSU, and then retest the system after reinstall, or unbolt the GSU from the G3. Neither are convenient.
I urge everyone to mount the GSU25 like an external component elsewhere, and leave the pitot static lines fixed.

Peter

[gregc]

I mounted mine to fuselage tubes behind the baggage area (Companion) and still had a vibration issue. Tech support had me shorten and more carefully secure both the wiring bundle and the pitot and static lines. That and some anti-vibration stand-offs corrected the problem. My take away is that the GSU25 is pretty sensitive and a solid installation in the best possible location is worth the effort.

[Lee]

That will be really nice. will you etch the lettering in the anodization?

That is the plan. Ceracoat is the other option and I will (laser?) etch through that also. Still exploring these two options with local vendors but I have to make up my mind soon...
Lee

[arborite]

I’d like to pass along a few tidbits related to this.

- Garmin actually specifies a .090” panel for installation. This is largely unheard of in the experimental world, but the standard in the certified world. So just understand that they are looking for some rigidity for their instruments.

- When using a panel of 080-090 you can tap the panel for mounting screws, although using single leg nut plates is the common install method. I never use the Garmin backing plate for install. While it may have some small value on thin panels (030-050) I’d rather see one use a thicker overlay if desired.

- While Garmin created a mounting location for the GSU25 on the back of the G3, it’s not a great location unless it’s the only space available. In addition to vibration potential, the biggest issue to access to behind the panel.
The G3 when mounted by itself allows great access via 4 screws, two plugs and a coax disconnect.
If the GSU is mounted there you have pitot static and aoa lines attached as well as the two GSU connectors.
you can either disconnect the lines from the GSU, and then retest the system after reinstall, or unbolt the GSU from the G3. Neither are convenient.
I urge everyone to mount the GSU25 like an external component elsewhere, and leave the pitot static lines fixed.

Peter

Very good points. i had the same concerns so was trying to make the panel rigid enough to be a solid mount. I am trying very hard to keep this plane as light as i can, so anytime i can eliminate another bracket, i do it. having said that, though, i think i may revisit the GSU mount. all the other avionics remote modules package very well just ahead of the panel in the triangular brace area,so wiring length is pretty short. Adding a service loop is actually a challenge they are so close together. I’ll explore making a small bracket for the GSU at the weld cluster up front. thanks for sharing your experience.

[500AGL]

Here an example that may help some. It’s a carbon cub that was undergoing a full panel upgrade, and there is not much room, which is typical of super cubs. But still enough for a full IFR panel.

Keep in mind you can stack your LRU’s behind the panel, but again, think about being able to access/remove/replace during the install. Through the G3x opening is best but often something will need access from below. Use nutplates, studs, etc and orient them in the direction of access.

As much as we think they are in for good, often you need to get in and out for some reason.

The GSU25 in this case is mounted upside down to a bracket that is adel clamped to the fuselage tubes. And if you look real close you will see a IBBS backup battery mounted to another bracket that is adel clamped to the tubes.
Everything orientated and fastened to allow direct in/out with the connectors. The components will come out separately as well except for the GEA in the stack, which was comprised for space considerations.

*One note to not overlook on the GSU25 - if you’re not using an AOA Capable probe, (so AOA not used) the AOA port must be plumbed into the static system.

[arborite]

thanks for those pics. I was looking today and decided that location is good for the GSU25 upside down as pictured. so far, my LRU count is pretty low, so i think i can avoid stacking - want to be able to access everything both through the big front hole as well as from underneath. No avionics will live as long as the plane hopefully, so service is a big deal for me. it seems every airplane I get involved with I end up upside down in the front footwell trying to do something behind a panel. need to make it easy, and the LSA is really roomy compared to just about any production plane.