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Advice for slightly frustrated RV-9A builder

C

CaptPausert

Active Member
I have had a few issues while building my elevator that have me a bit frustrated and thought I should get a bit of advice on how to proceed.

A few weeks ago, while dimpling my elevator skins I creased the skin in a few places due to not getting it flat enough in the DRDT-2 (didn't realize it until i turned it over). The creases aren't horrible, and the skin was probably usable, but it looked really ugly, so I decided to order a new one. after a week I got my new skin from Vans only to discover when I opened the box that it had a dent in it from the factory. Vans was really good about sending me a new one which I received today. I built up and match drilled it then decided to peel off the plastic before deburring and dimpling. I had the plastic mostly off but when pulling the plastic near the hinge cutouts the skin buckled and left a really bad dent in the skin. So now I have three bad right hand elevator skins.


So the question is should I take another week break while I wait for a new skin (already have the horizontal, vertical and rudder built) and continue with the elevator or should I set the elevator aside for now build my wing assembly stand tomorrow and start in on the wing kit that I got a couple of weeks ago? I will say I am a bit nervous about the first steps on the wing being to countersink the main spar.

Thanks
 
There's not really a right or a wrong answer. I've had the gut wrenching feeling of creasing and denting skins. At first it really bothered me and I always wanted new parts, then I spoke to more and more people who would look at the parts and just laugh - unless you're planning on polishing and not painting, an awful lot of mistakes can disappear with some filler before paint. I haven't gotten to that point myself, but it's been the common theme of advice I've received. At this point, if I ding something up, I just circle it with my sharpie and move on. Of course there's a limit, and it's hard to know without pictures, but I'd just say don't jump to assuming you have to scrap a skin every time you make a mistake. Many are fixable. If you really make a terrible crease and can't bring it back to mostly flat, well, that may be a different story.

As far as moving on to the wings, your call. If you're nervous about working on the skins or spars, you've got an awful lot of hours of fluting and edge finishing that can be done on ribs while you count to 10 (1000?) over your mistakes.
 
Build on

CaptPausert said:
I have had a few issues while building my elevator that have me a bit frustrated and thought I should get a bit of advice on how to proceed.

A few weeks ago, while dimpling my elevator skins I creased the skin in a few places due to not getting it flat enough in the DRDT-2 (didn't realize it until i turned it over). The creases aren't horrible, and the skin was probably usable, but it looked really ugly, so I decided to order a new one. after a week I got my new skin from Vans only to discover when I opened the box that it had a dent in it from the factory. Vans was really good about sending me a new one which I received today. I built up and match drilled it then decided to peel off the plastic before deburring and dimpling. I had the plastic mostly off but when pulling the plastic near the hinge cutouts the skin buckled and left a really bad dent in the skin. So now I have three bad right hand elevator skins.


So the question is should I take another week break while I wait for a new skin (already have the horizontal, vertical and rudder built) and continue with the elevator or should I set the elevator aside for now build my wing assembly stand tomorrow and start in on the wing kit that I got a couple of weeks ago? I will say I am a bit nervous about the first steps on the wing being to countersink the main spar.

Thanks
Click to expand...

How about working the opposite elevator?
Errors are personal preference. I replaced a couple fuse skins.
I would build on and go back when the part arrives. Don't sweat the countersinks. Just set the cage too low and make a pass. Measure and make another pass. Lots more on the longerons.
As you get through the fuse, there will be numerous steps you have to pause and set aside while waiting on or completing something else. It's common to have a lot of balls in the air.
I reset the shop about once a week because I start misplacing stuff and have to ask Sweetie to help me find it.
 
Last edited:
CaptPausert said:
I have had a few issues while building my elevator that have me a bit frustrated and thought I should get a bit of advice on how to proceed.

A few weeks ago, while dimpling my elevator skins I creased the skin in a few places due to not getting it flat enough in the DRDT-2 (didn't realize it until i turned it over). The creases aren't horrible, and the skin was probably usable, but it looked really ugly, so I decided to order a new one. after a week I got my new skin from Vans only to discover when I opened the box that it had a dent in it from the factory. Vans was really good about sending me a new one which I received today. I built up and match drilled it then decided to peel off the plastic before deburring and dimpling. I had the plastic mostly off but when pulling the plastic near the hinge cutouts the skin buckled and left a really bad dent in the skin. So now I have three bad right hand elevator skins.


So the question is should I take another week break while I wait for a new skin (already have the horizontal, vertical and rudder built) and continue with the elevator or should I set the elevator aside for now build my wing assembly stand tomorrow and start in on the wing kit that I got a couple of weeks ago? I will say I am a bit nervous about the first steps on the wing being to countersink the main spar.

Thanks
Click to expand...

Where in OKC are you? There are many RV owners/builders in the metro. You can click on the link in my signature below for my phone number if you would like to call to discuss your build with me anytime. Are you a member of an EAA chapter? There are three of them in the OKC area. Please don’t feel that you are building in a bubble. There are many builders in your immediate area to talk with. Give us a call anytime you feel bogged down.

You already have some good advice from the above posts. Keep building on.
 
I put a crease on an elevator skin for a stupid reason that I will not go in to. It was on the bottom skin so I decided to build on. After 200 flight hours and a paint job I occasionally notice it if I am looking closely during a pre flight inspection but mostly I forgot about it. I am good with almost perfect if it is only cosmetic….personal choice.
 
I built my 9A with 2 rules. I managed to keep them about 90% of the time.

1) Do something every day, even if it is just going out to look at the project or look at the plans again.

2) 3 strikes - 3 mistakes or problems ends the working session. No exceptions. It will not get better today.

These seem to conflict in your case, I'd suggest taking a break for a while to clear your head, but do something else on the project while you wait. Grab a chair, sit in your workshop and look at the plans and make airplane noises. Start thinking about the finished product and contemplate things you haven't taken the time for yet. You should soon get to a point where restarting the troubling work becomes a compulsion. Then go knock it out of the park.
 
I built 6 RV-14 trim tabs and although #4 and #5 were fine by most standards, I would not let it conquer me ... I absolutely WAS going to built a perfect trim tab ... build on brother!

Funny, ordering parts to build new ones, a set of parts showed up, messed it up by 10:00a, called VANS and Barbara said "You have a set out for delivery" ... "Nope, send another" ... they probably thought I was insane.
 
We all have SNAFU's. 13 months ago, I was in final assembly of the RV-10. Upon doing system checks, the fuel pump wouldn't work, so I spoke with the fine folks at Airflow Performance. They ship the pumps full of hydraulic fluid and it had leaked out/evaporated and the remainder hardened in the pump. I returned the pump and they tried to flush it and were unsuccessful. That was Pump 1.

So I had them send me a new pump - Pump 2.

When it arrived, I unboxed it, immediately took it to the airport for installation. And proceeded to snap off the brass (not cadmium plated steel) electrical studs. That was the demise of Pump 2. I called them on the spot and confessed that I was their dumbest customer ever. But I needed them to send me Pump 3 ASAP.

Pump 3 is installed and flying.

Stuff happens. Keep your head up and move forward.
 
Take breaks and work on something else if you can. I know during the empennage stage the plans are linear--do this, then do that, then do that. It's harder to skip around. By the time you're at the fuselage and beyond, you'll be able to ignore the frustrating part for months and not feel like you're getting behind.

I keep this pasted up front and center in my workspace. It helps to remind me to take breaks and stop when I get raged:

 
Thanks for all of the advice. I just went and bought the lumber for making my wing stands. For those in OKC I am just south of the heart hospital on 240. I am probably going to need some help with riveting at some point. I am willing to trade assistance if someone needs an extra set of hands.
 
Brian,
You mentioned countersinking the main spar worries. That is a good worry to have. The countersink can get wobbly and ream out the holes more than you want pretty quickly. The RV dudes in your area can help.

Im trying to remember the trick I used after making egg shape holes in a couple places. I know it was a piece of hardwood clamped the underside of the spar with match drilled holes into it. I think I had to round the edge to get a good fit into the underside of the spar. If you have a metal shop try and get a piece of scrap and practice. I was able to save my spar but it freaked me out after the first 2 holes I tried were ****!
 
rockwoodrv9 said:
Brian,
You mentioned countersinking the main spar worries. That is a good worry to have. The countersink can get wobbly and ream out the holes more than you want pretty quickly. The RV dudes in your area can help.

Im trying to remember the trick I used after making egg shape holes in a couple places. I know it was a piece of hardwood clamped the underside of the spar with match drilled holes into it. I think I had to round the edge to get a good fit into the underside of the spar. If you have a metal shop try and get a piece of scrap and practice. I was able to save my spar but it freaked me out after the first 2 holes I tried were ****!
Click to expand...

I just followed the instructions and it worked out fine - countersink for the platenut attach holes (these aren't that deep, so the countersink centers fine), then rivet on the platenuts. With the platenuts on, you can then countersink the screw holes. The platenut keeps the countersink bit centered well enough to not cause issues.
 
yeah I was debating between the plate nut method and the method I saw with the match drilled backing plate.

The issue with the backing plate is that there is enough tolerance in the hole diameters and the platenut holes that if you counter sink based upon the backing plate and then attach the platenuts if you don't get the platenuts centered perfectly then your screw doesn't necessarily align with the countersink and dimples and that could cause issues.

If you use the Vans method then the countersink for the screws is centered on the platenut and everything stays concentric.

I think if I was designing this, I would have made the spar cap thick enough to avoid having centering issues as well as not knife edging the countersink and then I would have used floating nutplates to avoid the centering issue. I talked about this with a design engineer friend of mine that works for Beechcraft and he concurs with me. The extra weight would be minimal in comparison to the improvement.
 
CaptPausert said:
yeah I was debating between the plate nut method and the method I saw with the match drilled backing plate.

The issue with the backing plate is that there is enough tolerance in the hole diameters and the platenut holes that if you counter sink based upon the backing plate and then attach the platenuts if you don't get the platenuts centered perfectly then your screw doesn't necessarily align with the countersink and dimples and that could cause issues.

If you use the Vans method then the countersink for the screws is centered on the platenut and everything stays concentric.

I think if I was designing this, I would have made the spar cap thick enough to avoid having centering issues as well as not knife edging the countersink and then I would have used floating nutplates to avoid the centering issue. I talked about this with a design engineer friend of mine that works for Beechcraft and he concurs with me. The extra weight would be minimal in comparison to the improvement.
Click to expand...
The extra weight would have been substantial considering the purpose of the extra material.
Nut plates riveted slightly out of position but countersinks well centered on them is not a good thing because the holes in the tank skins are positioned expecting the countersinks and nut plates being accurately located.
A tip that helps with this is to locate the nutplate with a screw ( finger tight is sufficient) while riveting the nutplate at each hole location.
 
I haven’t read all the posts, so maybe it’s been mentioned already, but regarding the damage caused while dimple countersinking, if the creases are slight, they can often be repaired to where they are not even detectable.
I have done this many times by tightly closing a set of dies on the dimple that has the crease, and then massage the skin with hand pressure in the reverse direction from how it was creased.
This might require a helper to hold the pressure on the dimple dies while you concentrate on, positioning the skin, and tilting it in the opposite direction of the crease.
 
CaptPausert said:
yeah I was debating between the plate nut method and the method I saw with the match drilled backing plate.

The issue with the backing plate is that there is enough tolerance in the hole diameters and the platenut holes that if you counter sink based upon the backing plate and then attach the platenuts if you don't get the platenuts centered perfectly then your screw doesn't necessarily align with the countersink and dimples and that could cause issues.

If you use the Vans method then the countersink for the screws is centered on the platenut and everything stays concentric.
Click to expand...

I swear this comes up every six months. Many builders think they know better than to just follow the instructions.
I’ve seen first hand the results of smart people thinking they know better and machining up all kinds of unnecessary jigs/plates/clamps to do this simple task.
The pillowing Scott mentions is real. I’ve seen it. It’s a real shame.
On top of that, you’re taking a 2-3h job and turning into a 10-20h job.
It’s just not worth over thinking it.
I think there should be an extra bit of instructions in the plans to nudge people into understanding the process and to do it the way it’s designed.
 
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