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avionics rack alignment to panel

tomhanaway

Well Known Member
Did a search and can't find exactly what I'm looking for.
Mounting 430w, sl30, gtx327 and pse 9000b. I understand the whole aluminum rail mounting concept.

My difficulty is where the front of each rack should be. I have the racks and wiring harnesses but don't plan on purchasing the avionics until close to final assembly so I can't just put the avionics in themselves. If I had the actual radio units this would be relatively easy but I don't.

For example, the Garmin install manual for the 430w talks about a 6.3" x 2.7" hole which would actually allow the whole rack mount to slide though the panel and the front of the rack could be slightly though the panel. Others seem to have cut the panel hole slightly smaller (say 6.25" x 2.65" for discussion) and have the mounting rack terminate just behind the panel.

How do I allow for actual differences in depth of faceplates of different units?
Is the best approach to mount racks so that they all come "just up to" the back of panel? Presumably this would have the various avionics protruding into the cockpit by slightly different amounts. Not enough difference to be noticeable?


All help appreciated :^)

Thanks,
Tom Hanaway
Boynton Beach, FL
 
Take your time on this part and look in each manual. If I remember correctly the SL30 is an oddball in both width and where the front needs to be.

I'm not much help but definately don't make them all the same.
 
Be sure to measure an acutal unit!

I found that the width varied slightly, but the mounting depth was a bigger problem. If you want all the radio faces flush with each other, the only way you can be sure is to have the radio in hand, or at least take very careful measurements of actual units...

My advice would be to order the radio stack when you're ready to build the rack, but hold off on the EFIS or other instruments 'till you can't wait any longer. The radios are not likely to change, but the EFIS / MFD world is changing much faster.

Good Luck. You'll be gassed no matter what when you push that throttle in for the launch...:D
 
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How about a visual?

Had the same problem,.. almost! I have the 9000b, 430, 330 and sl40 but the issues are the same with the 30 and 40. To get all of the faces to line up the trays must be in different places. I think the picture tells it all pretty well.

You really need the equipment, not just the trays.



Once they all lined up where I wanted them, I drilled a temporary plate of scap aluminum on each side to hold them all together. Then put it in the rack and drilled it to fit. No trouble if you have the equipment but not sure how you would do it with only the trays.

Hope this helps!

Bill S
7a finishing
 
Rack set back.

Hi Tom:

I was planning on tackling the same job in a few weeks. Only I'll be using a SL-40 and GTX 327. I have a air gizmo to mount my GPS on the top of the stack.

If you come across the proper set back from the face of the instrument panel I sure would appreciate you sharing it.

Perhaps some one who has gone before can share it with us?


cheers, terry.


P.S. I purchase my trays and will be purchasing the actual radio and transponder from Stein.

You got your ears on Stein?
 
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Mounting trays and mounting depth

I found that the width varied slightly, but the mounting depth was a bigger problem. If you want all the radio faces flush with each other, the only way you can be sure is to have the radio in hand, or at least take very careful measurements of actual units...

My advice would be to order the radio stack when you're ready to build the rack, but hold off on the EFIS or other instruments 'till you can't wait any longer. The radios are not likely to change, but the EFIS / MFD world is changing much faster.

Good Luck. You'll be gassed no matter what when you push that throttle in for the launch...:D

Terry is right, each of the mounting trays needs to be mounted at a different depth behind the panel to get everything to line up. For example, I chose to mount the trays so that the back edge of the bezels all sit flush aginst the front of the panel. For the avionics I installed, that requried the following distance from the front edge of the mounting tray to the front of the panel.

GMA-240, .135"
SL-30, .030"
GNC-300, .166"
GTX327, .120"
 
You Don't Necessarily Want Everything Lined up

I have everything lined up, but after 120 hours I now realize that I am going to change that. Specifically I have had issue with myself and the copilot inadvertently changing settings on the transponder and the audio panel. Now I have on my "to do" list recessing the transponder and audio panel so the front edges are flush with the panel rather than the other avionics.

Hans
 
Radio mounting

Just went through painful problem with SL30 mounting. Tube should be flush with front surface of panel according to my installation manual. It was in fact behind the panel and the locking screw mechanism was maladjusted so the radio didn't pull in fully. Also the panel cut out was too small. Net result the pins did not mate effectively - sometimes the radio worked and other times it had no power. It's best to have the radio seat fully in the tube and to do that the panel cut out must be proper and the front edge of the tube flush with the panel (in front). Give me a PM if this doesn't seem clear. Bill
 
Did a search and can't find exactly what I'm looking for.
Mounting 430w, sl30, gtx327 and pse 9000b. I understand the whole aluminum rail mounting concept.
...

All help appreciated :^)

Thanks,
Tom Hanaway
Boynton Beach, FL

I had the same problem, using the actual avionics, you can see that they all have different amounts of bezel sticking out of the panel. Sometimes that is good, depending on your installation (like for shadowing,finger guarding, etc.) and the vertical arrangement of the avionics.
In general, for ROUGH fitting, make all the LOWER lips of the individual trays approximately even with the forward edge of your panel (the side away from the cockpit).
Then I would agree with the other post that suggested using a piece of scrap angle to fix the trays together as one piece, for rough fitting. When you finally get your boxes, you can make the final tweaks.
If you have a tip-up, watch out for your canopy frame swinging in to hit the upper-most grounding bar or d-sub connector. This will stick out behind (forward of) your tray. You may need to bring your top box down or aft to avoid interference.
If you have a garmin audio panel, it is not as deep as the rest of your stack, and the forward facing connectors will be the farthest away from the canopy rail. Good choice for the top box.

Good luck.
 
Is this gap analysis ?

Just to recap a couple of points!

Lining the trays up does not line up the faces! You have to align the faces with the units in the trays and then draw a base line! Mount the trays in the rack relative to the base line and then the faces will line up. Be sure to decide how far you want them to stick out. If they are flush, there is little to brace a hand on in tubulance.

It hasn't been mentioned but remember that not all Gamin units are really Garmin (?) Remember that Garmin bought Apollo a couple of years back so the SL30 snd SL40 are not orginal Garmin and the trays are actually narrower so in addition to the face not being in the same place, you have to shim from each side.

Pictures below tell the story. PM8000, GNS430, SL40, GTX330.

This is an SL40 tray versus a GNS430. They are not the same. The SL40 tray is about an 1/8 narrower which means it has to be shimmed on each side if it's in a rack mount.



This shows that if you line up the faces,... the trays are in different positions. This is a good time to add a reference baseline.



This shows the tray alignment and baselines with temporary bracket in place.



This is in the rack just before drilling with the temporary brace removed. Lock everything in place, take out the brace and the radios and drill the trays to the rack. I allowed for airspace because one of the units called for a min 1/8 airspace for cooling.




Hope this helps!

Bill S
7a finishing sometime
 
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