Today I deburred the top wing skin parts and dimpled the appropriate parts per plans page 16-2 Step 6. Test reassembled and everything fits pretty nicely. I had set up the DRDT-2 dimpler a while back for prior work and it was still set up well. It didn’t need any adjustment, and the dimples came out looking crisp and flat.
Tag: construction
Left Wing Top Skin Work
Today I finished Page 16-2 Steps 1-4 for the left wing. Countersinking the wing walk area went more smoothly than I expected. Afterward, I prepared for dimpling the top skin holes by removing the blue vinyl from the top surfaces of the W-1003 and W-1002 skins.
Time Lapse Videos:
Fitting Top Wing Skins – Part 1
Today, I got the top wing skin parts out of the crate and began fitting them to the left wing. Way back in the beginning of the wing construction process, I had made a mistake in drilling the J channel wing stiffeners in the wrong position. I had contacted Van’s Aircraft about this and they confirmed it was not a big deal to simply extend the length using a short piece of J channel at the wing tip, so I fit and drilled this piece today as well.
I used up every silver cleco I could find and still didn’t have quite enough for the whole wing. I guess I’ll have to order some more eventually.
Time Lapse Video:
Also, today I worked on drilling out and re-setting some rivets on the rear spar on the left wing that I didn’t like.
Assembling the Left Wing Rear Spar
Time lapse video of yesterday’s activity–riveting the left wing rear spar and associated parts. Total a bit over 4 hours of real work spread out throughout the day.
Outboard Aileron Brackets
Finished deburring and test fitting outboard aileron brackets yesterday. Need to final drill and machine countersink.
Also etched and alodined the left wing flap brackets and torque tube bracket assembly parts. Priming to commence when I have enough parts to justify a batch.
Primer Decision
I was running out of the SEM self etching primer and after thinking long and hard about it I decided to switch to a two-part epoxy primer. This was due to a number of reasons, but primarily because I was having issues with the SEM primer not adhering consistently. No matter how well I prepared some parts, it seemed I frequently had small spots that didn’t stick. I’m not sure whether this was due to the age of the primer (it is at least several years old, as it was included with the empennage kit that I bought, and the previous owner had it for some time before that). I am certain the metal was prepared well.
When the SEM primer stuck well it appeared to be quite robust. It is difficult to scratch when properly adhered. I just couldn’t get it to be consistent, whether that was due to age or some other unknown factor.
So I decided I was going to go with a spray-gun applied primer and after some searching around and talking to people, I decided on the Sherwin-Williams CM-0724400 chromate primer. I wanted a few things in a primer:
- Superior corrosion protection
- Adhesion
- Flexibility (physical)
- Epoxy base
- Light color
The first three are rather self explanatory. I wanted the light color because I think inspecting the aircraft will be easier if the internal parts are lighter in color. I think it will be more likely to show (or at least easier to see) cracks, imperfections, dirt, and leaks against the background of a light color primer. In addition, the lighter color will make it easier to light up the inside of a wing during inspections than a more absorptive shade.
I talked to a Sherwin-Williams technical support guy and even though I’m just a homebuilder, they treated me well and were willing to spend time talking about their products’ features and compatibility. The only disappointment I had was finding out that S-W will not ship aircraft paints to their local retail paint stores. I was hoping to reduce the hazmat fee associated with my order by having them ship it to a local store along with other stuff, but the paint store, while very helpful, finally had to tell me they couldn’t do it. I ended up buying the primer from Aircraft Paint Supply in Ohio. The rep from APS was very helpful, and I received the paint two days after my order. The Sherwin-Williams primer meets all of those criteria and it is a rather bright shade of yellow. I haven’t shot a coat of it yet, but I will be doing so soon once I finish a number of small parts for a painting batch.
Log Catch-Up
Just completed Page 14-2. Time to date 99.75 hrs.
Previous days included 6/1, 6/4, and 6/6 on which I did a lot of rib fluting.
2016-05-22 Log
Completed fabrication and match drilling of wing tie-down mounts. Etched and primed, installed nutplates. 1 hour.
Installed brackets by riveting. Installed aileron bellcrank brackets and torqued bolts. Applied torque seal.
Catch-up on Wing Progress
Over the last few weeks, I’ve completed a number of steps and logged in my paper log, but haven’t really updated the progress here.
So, in the interest of completeness, and while some primer dries, here’s an update.
4/23/2016
RHS Main spar countersinking–finished the rib/skin attach countersinks; need to complete nutplate holes.
3 hours.
4/26/2016
Received confirmation that J stiffeners can be extended with no negative (from Van’s Aircraft). Misalignment of spars and J channels required either re-making the channels or extending them.
Made Four J-Stiffener extensions approximately 9-1/8″ long each. This allows overlap of 3 rivets in the splice joint.
0.5 hour
4/27/2016
LH Spar bottom countersink complete. Top remains.
1.5 hours
4/30/2016
Machine countersank all lower fuel tank attach screw holes after installing the nutplates on the LH main spar
5 hours.
5/11/2016
Countersank RH main spar top tank attach screw holes
1 hour.
5/14/2016
“Completed Page 13-3 – Finished RH and LH main spar countersinks, installed inspection plate nutplates and countersank.
Spot primed. Widened hole in LH Spar–all per plans. Also primed spar web extensions and doublers.
5 hours
5/15/2016
“Completed page 13-2 step 4 – Web extension riveting, both wings.
Page 13-4, steps 1,2,3,4,5,7 completed L&R. 8&9 completed RH only.”
7 hours.
Total hours to date: 85.75
RV-10 SB 16-03-28 Kit
Yesterday I received the kit for the Van’s Service Bulletin 16-03-28. I had placed an order as soon as the kit became available. It was delivered in only a few days. Van’s charged $25.00, which they said is their production cost, plus shipping.
The kit is for both the RV-10 and RV-14, came in a padded envelope, and includes the following:
1. Paper copy of the Service Bulletin
2. W-00007CD (to be separated into parts)
3. A piece of pre-drilled angle (part number printed on a label but I forgot what it was) to be cut into parts.
4. W-1013D-R
5. W-1013D-L
6. W-1013E-R
7. W-1013E-L
8. Bag 2751 containing AN470AD4-7 Rivets
9. Bag 1320
10. Bag 1978 containing AN470AD4-5 Rivets
11. Bag 1166 containing AN470AD4-11 Rivets
12. Bag 2412 containing AN426AD4-7 Rivets
13. Bag 1121
There are no specific instructions for installing these parts as an initial construction–the instructions focus on retrofit of completed wings. It should be relatively straightforward, however. The flat parts appear to be thicker and “beefier” replacements for existing aileron bracket parts. In addition, instead of a sandwich of three parts making up the bracket, there are only two parts per bracket, with increased thickness.
There are two bracket pieces that are to be separated into multiple parts and installed on the forward and aft sides of the rear wing spar to provide additional resistance to flexing in the spar web.