What are the RV-12 builder "gotcha's?"

(I hope this can become a "sticky," but that is up to one of the moderators!) Since I am starting on a 12 build (with a high school group,) what have you found that is easy to screw up, or just plain miss in while building the 12? I have read a few of them here, but it would be nice to see these all together.

Bob Kelly

I would love that too. I have been trying to absorb and retain others errors, but since my kit won't even be here for two months, I am sure to forget most of them.

Hey guys - -

We early builders found most of the 'gotchas'. I'm guessing if you are starting now, the instructions are fairly good. I would just build along, and ask if you run into a problem.

John Bender

Here are a couple.

Measure three or four times and cut once.
Read the plan step, and again three or four times, then and only after you have looked at all of the related figures, including page 00 of that section, and understand, perform the step.
Mark the side of the piece you will dimple or countersink and re-verify you are dimpling or countersinking the correct side of the piece.
IF it does not fit, or cleco together, you have MOST definitely done something WRONG. Do not drill a new set of holes.
Safety first!! Eye protection/safe power tool use.

Other may have some other GENERAL gotchas.

Maybe I ask too much, but... As a builder and TC, I have a fair idea of problem areas with some of the RV models. It's hard to get a straight trailing edge, fuel tanks leak, aileron push tubes rub, etc. With the 12, I know there have been problems with the 12 fuel tank, but I really don't know the BEST WAY to approach that problem. If there is an area where it is easy to think you are doing it right and still have problems, then I (and I would think other builders) might like a heads-up. Maybe it is an area where you had to buy a replacement part; how did you miss that critical detail?

Actually, I hope John is right--I hope things are all spelled out correctly and well. After reviewing the plans, they do look really good. It is going to be a bit more difficult for me watching over a group build than doing an individual build, so this may be more important to me than to the average builder. I do, however, think many builders could benefit from it. Thanks for your input.

Bob

I made my share of goofs during my build. I started about 6 months after the initial group of builders, and almost all of the gotcha's had been corrected. I would concur with the others that at this stage it is very straight forward. The plans are very good, there is a lot of info available from previous builders, and Van's support is good. My mistakes were either the result of inexperience in the procedure or not reading and following the plans.

You just have to do it the Hard Way!

Sorry Bob, I think the only way to get all the answers you ask is to take a pad and go back to the beginning of the form and start reviewing forward to current date. Start around April of 2008 which is when Vans started selling the first kit. As you find fixes then jot them down on the Pad. You can use the search function also. Also you can check all the different builder blogs. As you go through the threads there are a few where a builder would list all the fixes he would suggest up to that point. I would say 95% of the directions are correct. After all you are building an experimental airplane and its not a perfect world. May be you could assign your other builders a time period after the date above to collect this info with thread name to reference to as they go. This is to broad a thread for a sticky. Good luck.

Bob and Don, two items come to mind, that you should be aware of. First of all, on pg. 25-05, you will see 2 large corner skins ( F-1277-L and -R). If you value your sanity, you will not final rivet these 2 skins until just before you're ready to paint (I'm serious about that!). You'll have to cleco them for several trial fittings, but don't rivet them until you have to. They get in your way, big time, for all sorts of later operations in the build. Secondly, perform the entire section 28 ( fuselage tunnel fuel system), prior to installing the fuselage sides. You will thank me for this one.. There is nothing in the LSA rules that says you can't do some of this stuff in a different order. VANS plans are generally wonderful, but some of the steps can be performed more easily, in a different order. Good luck with your builds. Steve Wyman, #0038 (flying)

steve wyman said:

Bob and Don, two items come to mind, that you should be aware of. First of all, on pg. 25-05, you will see 2 large corner skins ( F-1277-L and -R). If you value your sanity, you will not final rivet these 2 skins until just before you're ready to paint (I'm serious about that!). You'll have to cleco them for several trial fittings, but don't rivet them until you have to. They get in your way, big time, for all sorts of later operations in the build. Secondly, perform the entire section 28 ( fuselage tunnel fuel system), prior to installing the fuselage sides. You will thank me for this one.. There is nothing in the LSA rules that says you can't do some of this stuff in a different order. VANS plans are generally wonderful, but some of the steps can be performed more easily, in a different order. Good luck with your builds. Steve Wyman, #0038 (flying)

Click to expand...

Steve's suggestions are good ones.
If you look through the Teen Flight blog you will see that the two skins he mentions are still not yet installed (but after installing the magnetometer this past weekend, we are ready to do it now).

We took a different approach with the systems though. If you look through the blog you will see that we did what a lot of other RV-12 builders have done. We positioned the fuselage on it's side, low to the floor. This provides great access to the difficult to reach areas.

Thanks guys, keep it up! That is exactly the type stuff we are yearning for. I wonder if we could have a thread started so all these things could be in one location, will have to see who is the moderator.

Pay very close attention to the nut plate sizes. Research what size bolts and screws connect to them before you rivet. Turn the fuselage on it's side and make life easy for control rods, wiring, plumbing, etc. When it comes to the rudder pedals, install them completely before you rivet the shelf they attach to to the fuse. You just assemble the whole assembly to the shelf right on your workbench. You can then slide it right into place and rivet it in place. A large syringe from Tractor Supply with the outlet hole opened a little and a piece of the white plastic tubing slid over where the needle would go helps make a very neat bead of pro-seal on the fuselage. It looks like it came from a caulk gun.

Skip installing the rear glass until the absolute last minute. It'll make working on the plane 10x easier with it out!

And do as I did and Scott mentioned a post ago.

I riveted the turtledeck skins and installed the rear glass two days before the DAR inspection.

Two Cents

My Two Cents. Marty mentioned it but I think it needs to be repeated. From the start, Van's tells you to read each chapter completely through before doing anything. If you don't do that you will understand why you should. They also mention that the "step" order is of their own design and that you are more than welcome to alter the steps once you understand the finished product. I think we can all find a path that works best for us if we know where we're going.

Can't help with the fuel tank unless you are going EAB. If you are ELSA you must put in the plastic piece or your statement of compliance will be fraudulent. If you are EAB, it isn't necessary and offers too much potential for leaking (inside the cockpit!). I'm guessing there was an ASTM rule that said you had to have a sight gauge...maybe not. Just the same, most of the early builders (ELSA's) got their certificate and immediately covered the plastic with a piece of aluminum. We all sleep better now.

In an ideal world, we would have the "gotchas" organized by page number of the instruction manual from VAN's. Short of that we have all the good advices provided here above and throughout this RV-12 Forum. Just take time whenever you face a problem to check what others have said on the subject before asking. But even as the situation has evolved from the time of the "Bleeding Edge" pioneer RV-12 builders, it may be helpful to reopen an issue covered in the past. I find it rewarding to follow other Builders Blogs/web sites. For this purpose and as such a list did not exist I built one on my blog at:
http://vieilleburette.blogspot.com/2010/07/list-of-rv-12-builders-sites.html
By going through these sites you will eventually focus on a few to clarify or solve your problems (I recommend Schmetterling).
Don't hesitate to Blog your own "gotcha's", sharing them for the benefit of future builders.

Look at these from Joe Gores

http://www.vansairforce.com/community/showthread.php?t=34767

http://www.vansairforce.com/community/showthread.php?t=41661

http://www.vansairforce.com/community/showthread.php?t=41662