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motor or panel first

S

stamper

Well Known Member
I am building a 10 .I am at the point of ordering either the motor or IfR panel but cannot get both. I will be able to buy the other next summer and finish the plane. So what would be the best first. What did most of you guys do out there. Need help and advice.
 
My two cents is to get the engine first, by the time it is installed and your finances have recovered to buy the panel, the offerings for the electronics will have changed.

The world of avionics is moving extremely fast, wits as long as you can to get the little magic boxes of electrons.
 
With the motor you can go onto things like the cowl, spinner, etc. With the panel you'll only be able to go so far on "construction."

Food for thought.
 
motor

So if I do the motor first and do the finish kit is the dash and panel easy to work on with the cabin top on and all; or is it just more of a pain but due able to finish the panel with the top and front glass in. Thanks and thanks for the quick reply
 
Motor now. Next year the engine offerings will be the same but cost more. Next year there will be better avionics and they will cost less.
 
I did my panel after cabin top, etc, was all in place. With good planning you can minimize but not eliminate laying on your back under the panel.
 
Yes that was the question. Thanks. I'll look at your site to see what you put in your panel. I was happy to see your post on getting your plane done not to long ago.
 
I also did the motor first and then the avionics. I did almost 100% of my panel and avionics with the cabin top and windshield in. This does make it a bit harder and yes, some time on your back trying to get under and behind the panel. But for me, it was not overly bad.

Brian
 
I did panel and wiring first, including firewall penetrations, prior to hanging the motor. Two reasons... I wanted to minimise the time that the engine sat in pickled state and I wanted to have the firewall complete prior to hanging it. Engine purchase was delayed as long as possible.

Fuselage was upsidedown (and high off the floor) during panel so I was able to sit in a roll around chair rather than climbing in and out of the cabin.

The ceiling in my basement has a tire scuff mark on it. :D Did that while flipping it upright for the last time.

And yes I would do it that way again.

**EDIT** The thread has me curious now. I scratch built my panel and did all the avionics wiring which I knew would take considerable time. Is that true for the majority of the builders here that recommend engine first? I might buy engine first also, if the panel was being shopped out. Not criticizing, just curious.
 
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Like most have said, I agree that the engine should be first. All the cowl fitting is a royal PITA and you need the time to do a quality job. Avionics are in a rapid state of change recently, so you want to buy them about six months or so before you plan to fly. Any sooner and you might end up flying last year's technology.

Most of the newer EFIS have shrunk tremendously in size. They are now only a few inches deep, where they used to be six inches or more. You may still need to trim a rib to get the perfect placement on the panel. There are ways to accomplish this is a safe and structural manor. You'll also find depending on your avionics choices that you may have to get creative with your subpanel as well.

You can also delay riveting the upper fuselage assembly until the last minute. You can get it on and off, even with the canopy cover bolted in place. This allows you the benefit of working on a majority of the finish kit trmming and some of the fiberglass work. The benefit is that it is a whole lot easier to build your wiring harness with the upper fuselage assembly upside down on a table. You do have to have in at least cleco'd in place for several of the steps to get proper measurements, so you'll get good at taking it on and off.

Just remember, there is no "one" right answer. Everyone is going to have a different opnion on what's the right way of doing things. The way that turns out best for you is the right answer as long as you ensure that you aren't compromising safety.

bob
 
Motor technology won't change significantly in the year while you're installing your panel.

Panel technology may change significantly during the year you're installing your engine.

So do the engine first if you want to have the latest and greatest in the panel.
 
I did panel first but this is my second RV. I have a good handle on what goes forward of the firewall and where and I am making CPC connections for all the electronics, so I can completely close out the fuselage before hanging the engine. Once the engine is in place, making the connections back to the firewall (controls and plumbing as well) won't take a lot of time. I also found the cowling and spinner not to be that difficult. I expect to take about a month after arrival of the engine to be ready for first flight.

On the other hand, wiring is going to take a while. I have A/C, built-in oxygen, 2 axis servos, 3 axis trims, two EFIS AHRS and magnetometers, AOA, lighting, ELT, electronic ignition, door latch sensors, interior lighting, headset jacks, power outlets, etc. Along with finishing the composite work for the overhead, cabin top, and doors (necessary to coordinate with the wiring), I expect to take pretty much until Spring before I am ready to move on to the firewall forward. And even with Aerotronics having done most of the work behind the panel, this is still one task I would not want to take on with the forward deck, cabin top, and top forward tailcone skin in place.

Not that I disagree with those who have done it the other way around; this is just what works for me - my own style of working and fitting to my construction plan. It seems to me that either way you do it, you have to do some planning for the part that is missing; you can't install an engine without planning your panel connections and, vice versa, you can't install the panel without planning your engine connections.
 
I did the following for my 10. I bought the mounting cases for all the avionics and ran all wiring, then did engine and cowl. By the time I completed the engine and cowling, several of the avionics had been upgraded by the manufacturer. In my case, I changed my mind on one avionics upgrade. Only had to change one avionics bracket and 4 wires.

I'd do the same again. In fact, I will since I'm now building an 8a :)
 
Let me start with, I had both the engine and avionics in hand. I completed the cabin cover and fit the upper forward fuse, doors were done, etc. I then removed the upper fuse entirely and I wired the panel and all of the avionics outside of the fuse. It was extremely easy to make changes, cut holes in the sub panel organize and run wire bundles. I also used the Aerosport panel, which is easier to install prior to permanent mounting of the upper forward fuse. After the panel was tested on the bench it was mounted permanently, along with the cabin cover, doors, etc.

The engine was then mounted and the cowlings were completed.

I believe that I have seen some installations of the engine with the cabin cover and upper forward fuse not yet installed. That may be an option. All I can say is, it is a PITA to get under the panel once it's installed!
 
Engine first then "finish" the panel.
There is certainly a lot of work that can be done on the panel and especially behind the panel without getting all the electronics for the final panel installation.
In essence you can almost complete the electrical system behind the panel, ready with fuse sub panels eventually used for your electronics before getting to the engine. You should have a good idea of what kind of gizzmos you want to install when you are ready for it.

I am not a fan of installing everything without obstructions like windshield and fuselage cover because eventually you'll have to do some maintenance and having installed everything in a finished airplane will force you to create easy access, working from the seats rather than installing things from the top down with the forward fuselage cover off.
I installed only one item in the forward bay (Ignition Box) and the rest is mounted between the panel and first bulkhead.
It is very tempting to install all sorts of remote boxes in the front bay when the top is removed but this is one place you'll find extremely hard to reach after the airplane is complete.
 
Another engine first vote. While I have yet to install my panel (hopefully that will start this weekend!) I’m in line with most of everyone else’s opinions. I did so some thinking as to layout when I cut my panel so that I wouldn’t have any interference issues between the avionics and the upper fuse structure. I also prewired the fuselage and wings with power, ground, data and antenna wires that I will splice into my electrical /avionics harness still sitting on the bench. Another benefit of a multi-screen EFIS is you‘ve got lots of big holes that help with access to the subpanel area.
 
Well, here's some practical engine options:
1. Brand new (certified or experimental) through Van's
2. Used from wherever you can get it

I opted for a buying a C4B5 core and having it rebuilt. I did mine through Barrett (BPE) for just about the same a brand new XIO-540 from Van's would have cost, but it was worth it to me to get some of the extras that BPE does on their rebuilds. You could spend less, but from what I've seen, the good deals on good condition, used IO-540s for a steal have long since dried up.

Aerosport Power is another big player with an outstanding rep. Aerosport Power is another big player with an outstanding rep.
 
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stamper said:
Yes that was the question. Thanks. I'll look at your site to see what you put in your panel. I was happy to see your post on getting your plane done not to long ago.
Click to expand...

I do not have a web site but my panel is shown on the post "show us your panel" (RV10 area), page 19. Post 187.

Yes I did my own panel.
As others mentioned, you can do a lot of work thru the large holes where the efis will eventually go.
I bought engine and prop from Vans (discount if bought together). I also got an "OSH special" of free shipping and preservation. I left the preservation oil in until close to finished.
 
Btw, I was able to temporarily position my panel about 4 or 5 inches aft of its final position, and do a lot of the connector attachments from above, rather than below.
 
Engine first is my vote. I did not build our RV-10 but here is a point to ponder.

2-3 months ago a fellow was unable to finish his project because of unforeseen economic issues. He was trying to sell his 2 generation old EFIS at VAF classifieds for about 1/4th of what he paid for it. I don't think he even got a nibble.
 
Thanks for all the help. I will do motor first. If anyone is ever flying through Wyoming from September through April I live in Dubois Wyoming and would love to have you stop in and take a look at my project. I have room for anyone passing through and more then likely hanger space. So if your heading to Yellowstone or Jackson Hole Wyoming stop in please. Or if you want to just do a trip. Thanks Bruce.
 
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