Nov 06, 2022     18-8: Right tank finish up - (2.0 hours)       Category: 18: Fuel Tank

Prepped and primed the right tank. Ready for install. Mix 150g of part A Ekopoxy and had quite a bit left over. Finish was not as smooth as left tank. Need to turn up the paint a bit to get it to flow. It was maybe a little warmer today.

11/8: dimpled tank and installed. Easy peasy. Temporarily held with clecos.

11/11: Neighbor helped me pull the left wing out of the cradle so I could access all the right tank screws. Installed all the AN bolts through the spar and torqued. Right wing tank is done.

  Nov 02, 2022     18-8: Left tank done - (3.0 hours)       Category: 18: Fuel Tank

With the left tank leak free, I decided to prime it with a final coat of Ekopoxy. This would satisfy my OCD need to have a nice uniform primed finish and provide a little more resistance to fuel and solvents. I had not used the Ekopoxy yet and was concerned about how thick it is. I stirred the thick part A with a paddle mixer on an electric drill. The Part B was much thinner viscosity and when mixed with part A resulted in an almost flowable paint, but not sprayable. I added the recommended water to thin it a bit and it was still a little thicker than I'm used to but worth trying before thinning more.

After thoroughly cleaning the soapy residue off the tank, I sprayed a tack coat and then a second coat but it wasn't flowing out well. Ran out of paint and mixed up another batch. Added a little more water this time, about 20-25%. Flowed out better and didn't run. Very happy with the results. Will target 20% water on future mixes.

Primed the pitot mast too while I was at it. Came out really well.

After a few hours, I decided to proceed with dimpling the tank. At the very least it would give me a data point for how well the primer takes a dimple after 3 hrs cure. No issues. With the dimples done I guess I could hang the tank. Wasn't sure I'd get it in place by myself but it actually wasn't that hard. Installed a couple AN bolts in the spar to keep it in place then proceeded with all the #8 screws in the bottom. Then finished installing the AN bolts and torqued them. Will need to get the top #8 screws when I have some help to move the wing out of the cradle. Looks great though!

11/5: wife helped me lay the wing on a table
So I could get to the top screws. Had to do a little filing of the edge of the tank skin to get it to lay flat. All screws installed. Looks awesome.

  Oct 28, 2022     Fuel tank repair 3 - (2.0 hours)       Category: 18: Fuel Tank

Received my third repair kit from Van's. Got everything prepped and cleaned with acetone as best as possible. Mixed up some proseal and filled two small syringes to get into the tank.

Used the syringes to apply a new bead above and below the existing bead in an attempt to slather new beads in there. It was all blind. Used a popsicle stick to try to make some fillets. Camera confirmed I had applied a good bit of proseal in the problem areas.

Put a little proseal on each rivet hole in the back baffle and applied two continuous beads, one inside the rivet line and one outside. Inserted two rivets into the repair plates to help align and installed the back baffle repair plates. Installed remaining rivets and pulled them all with the pneumatic squeezer. Good squeeze out on all.

We'll see in a few days how we did.

10/30: proseal was pretty well cured so thought I'd see how we did. Set up the manometer and pressurized. It was immediately dropping and quickly. I could actually hear the air leaking out. $?&@$!

It is leaking out the rivets that I put in the patches. They're hermetic rivets but appear to be leaking right though the center hole. Other leaks appear to be sealed but without it holding any pressure it is tough to be sure. Nothing left to do except slather proseal over the river heads from the outside. Order more proseal.

11/1: quick turnaround on the proseal from ACS. Took the opportunity to seal up the rivets. I figured that if I drew a vacuum with a small dollup of proseal on each rivet that it would draw down into the stem of the river. Worked pretty well. I applied a little to each and as I drew the vacuum, I could hear them hissing again. On several of the rivets I could see that it had formed a small hole in the dollup meaning it had drawn in. Good. Reapplied proseal and actually couldn't hear the hissing anymore. Removed the vacuum, and the. Applied a large Hershey kiss to each rivet. Put a fillet around the outside of the plate for good measure. I'm optimistic.

11/3: Finally! Right tank passes leak check. What a milestone.

  Oct 22, 2022     Fuel tank repair 2 - (2.0 hours)       Category: 18: Fuel Tank

Got my tank repair kits from Vans and started on cutting the holes in the back baffle. I'm a little concerned now that the leaks potentially extend across three bays. My attempt to proseal from the outside likely extended the apparent limits of the leak, but with all the proseal removed it still appears to leak from the ends. Just to be safe I will seal all three bays. I need another patch kit then.

Cut the holes a few different ways, none is great. I tried drilling a perimeter of holes and then snipping out the skin between. This leaves a very rough, almost saw tooth edge, that quickly eats up the sanding drums I was trying to use to smooth it. On the second one I used a carbide bit in the dremel to just cut it out. Came out a little better but time consuming.

I also purchased a $40 borescope for my phone to get some visibility on the repairs. The existing proseal beads look pretty good to me, but they apparently leak. I'll just lay a new fat bead in there and cross my fingers.

10/23: last night a strong gust of wind blew my tank off the table it has been sitting on outside. It bent the bottom skin a bit in the corner, but I was able to bend it back by hand. Hardly noticeable. Lucky.

  Oct 11, 2022     Fuel tank repair 1 - (2.5 hours)       Category: 18: Fuel Tank

My A&P brother and A&P nephew were in town and convinced me we should try to draw a vacuum on the tanks and suck proseal into the leaks.

First step was figuring out how to safely draw a vacuum. Rigged up the manometer to the vent line to read the negative pressure of 27” of water or about 1 psi. McGuyver'd together my shop vac, a kid's cup and a medicine syringe to pull a vacuum on the fuel drain line.

After proving the vacuum concept, mixed up some proseal and applied to the vicinity of the left tank leak. Drew the vacuum and initially it didn't hold. But the proseal appeared to seep into the space between the baffle and the skin and eventually it seemed to hold the vacuum. Let it sit under vacuum for about 30 minutes and the pressure seemed to stabilize.

Moved onto the right tank. Similar, but less conclusive results. Seems to hold but was slowly losing vacuum. Weather was also changing so we'll see.

10/12: after 24 hrs was anxious to check it. Probably should have let it sit longer. It was leaking right out the end of the proseal I had applied. I think that is a sign that it was a superficial seal and didn't really seep into the joint. I scraped all the proseal off and redid it, extending it further along the seam and drawing the vacuum for at least two hours on the left and then overnight on the right tank. Seems to be holding but who knows. Will patiently wait until the weekend to test it.

10/15: right tank is still leaking in the same spot. And I found another spot. Good news is that I think the left tank is sealed. No bubbles around the repair and it is holding pressure on the manometer.

10/17: left tank is good. Decided to make one last pass at the right tank before cutting it open. Bought some toluene to lightly thin the proseal. Used about 10% by weight. Applied to both areas that were leaking. It still doesn't viably draw into the seam so I'm not hopeful. If it at least fixes the new, smaller leak then I won't have to cut two holes. We'll see.

  Oct 06, 2022     Tank leak found - (2.0 hours)       Category: 18: Fuel Tank

For weeks I have been inflating balloons, tightening clamps, replacing balloons, repeat…convinced that the slow leak was related to my balloon connection.

Today I finally made a manometer to more accurately measure the pressure and mostly to eliminate the balloon from the equation. After getting it all set up I could very quickly see the pressure was dropping. I sprayed the back baffle with soapy water and there were clearly bubbles coming out along the seam. In the last month I have sprayed every inch of that baffle a hundred times and there were never any sign of bubbles. Then with the manometer setup, it was so obvious.

Started researching ways to fix it. Some suggest drawing a vacuum on the tank and it will draw the proseal in from the outside. I'm not sure how well that will work. I'm just going to bight the bullet and order some repair kits from vans.

At least I found it.

Figured I'd move the left tank over and double check it too with the manometer. Sure enough, it's leaking too. Right out at the end. Guess I'll get two repair kits.

  Sep 10, 2022     18-8: Right tank finish up - (4.3 hours)       Category: 18: Fuel Tank

Got the right tank prepped and primed this morning. Forgot to mask off the areas on the back baffles for the zee brackets, but just cleaned the areas with acetone after painting.

9/11: sealed up the back baffle this morning. Broke my rivet puller on the last rivet.

9/14: finished up the final countersinks and rivets in the right tank. satisfied that the left tank was holding I moved the balloon and schraeder valve over to test it. Looks like it's leaking around the fuel pickup. I removed it and put more thread sealant on and reinstalled. Still leaking. Hard to tell if it's the pick up or through the skin adjacent. Pretty sure it's the pickup.

9/15 am: removed the fuel pick up, cleaned it all up with acetone and resealed it with a healthy bead of loctite 567. Re-inflated the balloon and it seems to be holding.

9/15 pm: balloon was deflated when I got home. :(
I can't find the leak and getting frustrated. My wife casually mentioned that those are really cheap balloons I was using. And I had reused the one from the left tank. Could it just be the old cheap balloon slowly leaking through the skin? I replaced the old balloon with a new one and it seems to be holding. I also inflated the old balloon and ties it off; in an hour it had noticeably deflated.

Lesson learned - don't use old balloons.

9/25: have been chasing a slow leak for weeks in this tank. Balloon holds for 2 days, but slowly is getting smaller. By the 3rd day it is completely deflated. So am I. Can't find a leak anywhere.

  Sep 05, 2022     18-8: Sealing up left tank - (2.5 hours)       Category: 18: Fuel Tank

Decided to bite the bullet and seal up the back baffle on the left tank. Watched than Vans video one more time over the weekend and felt prepared. Laid out all my tools and got after it.

Cut a little off the tip of the proseal applicator to produce a little thicker bead. Laid the tank on its side (bottom down) and laid a nice bead just below the rivet line. Flipped it over and did the top. Then did the end ribs and got big blobs into the corners. Put just a small amount in the outermost holes of the interior ribs per the video. Dropped the back baffle in place without smearing it around and cleco'd every hole in the skins and ribs. Looks good so far. Set the outermost blind rivets in the ribs. Then removed every other skin cleco and set the skin rivets with the squeezer. Then removed all but every 10th cleco and set the remaining rivets. Repeat on other side. Then set the blind rivets for the zee brackets. Put just a dab of proseal on each hole and swirled each rivet then set them. I don't know if the zee brackets on the RV-10 are wider than older models, but I had plenty of room to get my rivet puller on the rivets and did not need to use the wedge method.

Got it set on its back to let what little bit of sag in the proseal work for me. Will let it sit there for a few days and cross my fingers. All and all pretty easy, but who knows.

9/7: finished off the tank this morning countersinking the few remaining holes in the skin and setting the last few rivets. The proseal left on the plate appears to be fully cured so I bit the bullet and strapped on a balloon to the vent line and pumped it up. It appears to be holding and no sign of bubbles in the soapy water. We'll see.

9/10: balloon is not holding. Suspect it is leaking around the balloon itself. Need a better clamp.

9/12: wrapped the vent tube with silicone tape and pulled three tight zip ties. Seems to be holding.

  Aug 26, 2022     Water leak check and fix - (2.5 hours)       Category: 18: Fuel Tank

Decided to leak check with water before putting the back baffles on. Didn't figure I'd find any leak, but better safe than sorry.

Filled up the left tank and could immediately see the stream of water coming out the inboard leading edge. The out board is leaking a little too. Obviously not enough proseal in those areas.

Right tank passed with no issues.

8/27: rinsed out the tanks and let them dry, then scuffed the areas at the leading edges and cleaned with acetone. Then mixed up about 30g of proseal and worked a nice thick fillet into the nose on each end. Slathered a little on the outside too for good measure. Will check it with water again when it cures.

8/30: rechecked the left tank with water. Passed!

9/1: primed outside of left tank

  Aug 19, 2022     18-5 thru 18-7: Last ribs for left tank and fuel sender - (3.2 hours)       Category: 18: Fuel Tank

Got the j stiffener installed and the inboard bracket and rib in one session today. Left tank almost to same point as right tank.

8/20: started looking at the fuel sender. Bent the wire for the float, but went to measure the resistance and noted that there is a dead spot at the bottom of the range. I'll need to call Van's to get a new one.

8/23: Figured out the problem with my fuel sender - multi-meter user error. Got both sending units prosealed and screwed in place. Used stainless hex screws with the thought that it might be easier to remove them in the future if ever needed. Installed the remaining AN fitting in each tank and capped the fuel return lines for now.

  Aug 13, 2022     18-5: Left tank work - (4.5 hours)       Category: 18: Fuel Tank

Finally got the weekend time I needed to do some proseal. Got three ribs done in one batch today.

8/14: finished up the last three ribs this morning. Just the j channel and inboard tub left. Coming along.

Data point for future projects. One 3.5 oz tube will do three ribs with just a bit to spare. Put the tube in the freezer after applying to the faying surfaces to keep it from setting while you rivet. Pull it back with enough working time left to do the fillets and rivet heads.

  Aug 10, 2022     Fuel Return - AN Fittings - (1 hour)       Category: 18: Fuel Tank

After three tries to get the correct AN fitting for the fuel return line, I finally got it right. I just needed a 3/8" bulkhead fitting right?
1. Ordered an AN816-6D pipe to nipple transition for 3/8" tube. The 6D is for 3/8" tube. - WRONG. It's 3/8" tube, but also has a measured 3/8" pipe thread and I need 1/2" to go into the fuel return bung.
2. Ok, I've got this figured out. I need an AN816-6-8D - which is a 3/8" nipple (the -6) transition to a 1/2" pipe (the -8D). This fitting was surprisingly hard to find and had to get it from Skygeek. WRONG AGAIN. The 1/2" end was way too big, like 3/4" or more. What am I missing? NPT pipe thread is what I was missing. What measures approximately 1/2" is actually 3/8" NPT. So then why wasn't the original AN816-6D correct? 3/8" nipple and 3/8" pipe, right? No - standard transitions apparently are downsized on the pipe side. So, an AN816-6D is really the same as an AN816-6-4D. I guess everyone knows that.
3. So finally figured out that I need an AN816-6-6D and spruce carries those. Correct part finally arrived today.

  Jul 29, 2022     18-5: Back at the left tank - (3.8 hours)       Category: 18: Fuel Tank

After taking a week off for AirVenture, I got back on the tanks today. Got all of the stiffeners, the fuel flange, and fuel drain prosealed and riveted. Got it all done with one tube of sealant. Put a few once's in a sandwich bag in the freezer and then had that available for clean up.

7/31: mixed up 20g and got the fuel bungs and nut plates installed on the inboard rib and installed the inboard half-rib.

  Jul 17, 2022     18-2: More left fuel tank work - (4.1 hours)       Category: 18: Fuel Tank

Took some time this morning to clean the shop and then started disassembly of the left fuel tank. Scuffed the rivet lines on the skins and scuffed all the stiffeners.

7/20: woke up early and got some work done before work. Got the ribs scuffed and cleaned and then dimpled. Set up the drdt2 to get ready for the skins.

7/21: got the skins all dimpled and masked the stiffeners in preparation for proseal. Leaving for airventure tomorrow so that will wait until I get back.

  Jul 15, 2022     18-2: Starting left tank - (2.2 hours)       Category: 18: Fuel Tank

Got started on left tank. Fabricated the stiffener angles and cleco'd stiffeners and tank ribs to skin. Cut j channel and started match drilling.

Countersunk skin to back baffle holes.

  Jul 13, 2022     18-7: Rt tank fuel sender - (0.6 hour)       Category: 18: Fuel Tank

Tinkering around this morning before work. Pulled out one of the fuel senders and bent the wire per the dimensions in the plans. Fit pretty good, just bent a little to clear the vent line and ensure it was moving full range.

Full - 32 ohms, Empty - 232 ohms

  Jul 09, 2022     18-5 & 18-6: Right tank assembly 4 - (7.5 hours)       Category: 18: Fuel Tank

Took a little time off for holiday and work stuff but got back at it this morning. I have tubes of proseal which are probably good enough to do almost 4 ribs. I knew I'd be fighting the clock though and set out to do three. No way. With it so warm out, the tube was setting up after about an hour. It was enough time to do the faying surfaces and get everything riveted but by the time I went back to fillet the edges, it was set up in the tube. Had to mix another 30g to fillet the edges and encapsulate the rivet heads.

Had enough left over to set the -6 rivets and the anti-rotation plate on the left in board rib.

After watching the vans tank assembly video several times, one of my favorite take always is using the paper strip to scoop the excess proseal out of the dimples. Works great and keeps thing from getting too messy.

Not much time for photos today.

7/10: two more hours this morning and got the last rib and the j channel installed. I mixed a tube of proseal and put half of it immediately into a sandwich bag and put it in the freezer. Got the end rib done and then when I started applying the proseal to the j channel, I noticed it was a little streaky with I mixed proseal. Not good. Scraped that off and squeezed the remainder of the tube into another sandwich bag see if it got better; it didn't. So pulled out the good bag from the freezer and finished the channel.

Instructions suggest applying proseal to skin instead of channel but I could t see how that was going to work. I just laid the tank on its bottom and very carefully inserted the buttered channel. It worked fine with minimal smearing.

Got another 1.5 hrs in this afternoon. Fabricated the vent line, installed the attach bracket and then the final inboard rib. I'll put this tank aside for a while and may do some water leak testing once it is cured.

  Jun 25, 2022     18-5: Right tank assembly 3 - (3.2 hours)       Category: 18: Fuel Tank

Started installing ribs. Started with the inboard half-rib. Only mixed 8g and it really wasn't quite enough. I'll put some more on the fillets when I do the next rib. As expected, it is slow going and messy.

Mixed up another 40g to do the first full rib. Put as much of the proseal as I could into a ziplock bag and cut the corner off to make a little squeeze tube. This made doing the fillets much easier and let me really goop it into the critical spots. I didn't bother with a lot of masking and overall did a fair job of not getting proseal everywhere. I just kept the acetone and plenty of rags handy. I was able rivet everything myself except the front three rivets on the top skin; called the wife out to help with those and they were easy. The 40g is just the right amount for a single rib. It took a little over an hour.

I can see that my pint of proseal is not going to get me far, and with the larger quantities the 3.5 oz pre-measured cartridges may work out better than hand mixing. I'm going to go ahead and order 8 tubes to get me throught the tanks. I'll keep the pint for small batch items.

6/26 - mixed 40g again and did another rib. Really getting good at it and minimizing mess. Another 1.2 hours.

Purchases: ACS - 8 tubes of proseal

  Jun 20, 2022     18-5: Right tank assembly 2 - (3.5 hours)       Category: 18: Fuel Tank

Started attaching the stiffeners. Mixed up 40g and got 5 ribs done. I masked off the skins to keep them clean and that worked well. I should have masked the leg of the stiffeners too - I seem to recall others doing that.

6/22 pm - set three more stiffeners. 28g. Damn hot out there.

6/23 pm - mixed up 40g and riveted the last 4 bottom stiffeners. Had enough left over to do the drain flange too. Pretty straightforward.

6/24 - worked from home and squeezed in an hour at lunch. Got the remaining skin stiffeners on the top skin then riveted the fuel cap flange. Straightforward, just messy. Had one rivet sitting proud after it was all done and cleaned up. When ahead and drilled it out and reset it while the proseal was still wet. 26g for two stiffeners and the flange, quite a bit extra.

  Jun 19, 2022     18-5: Right tank assembly 1 - (1.5 hours)       Category: 18: Fuel Tank

After much research and consternation, I finally mixed up a little proseal and started assembling pieces of the tanks. Started with the end ribs. Ended up installing a -6 rivet in the tooling holes as others have done. Ordered the shortest I could from spruce and then shortened them a bit on the belt sander. Installed with proseal. Then installed the anti-rotation plate and the fuel bungs. I cleco'd the ribs into the skin to support them while I bucked rivets. Could have squeezed the fuel bungs but went ahead and bucked them as I was set up for it.

Got it all riveted then went back to seal up each rivet. Difficult to discretely seal each rivet so slathered on a good amount on the backside of each bung to try and encapsulate everything.

I put a little proseal on the nut plates for the fuel sender but will plan to encapsulate the entire nutplate and screws when the senders are installed.

Contemplated installing the return line AN fitting wet while installing the anti-rotation plate, but ultimately decided not to. Just very carefully cleaned out any extra proseal that would prevent it from seating in the future.

Total of 15g proseal to seal the external ribs.

  Jun 05, 2022     18-4: Final prep for right tank - (3.7 hours)       Category: 18: Fuel Tank

Disassembled right tank and scuffed the rivet lines on the skins. I've seen folks tape off the limits, but that seems like overkill. I traced the areas in sharpie prior to disassembly and then just scuffed to erase the marks. I deliberately went well outside the mark to get good bond in the fillet areas. Scuffed then wiped with acetone until clean. Took a lot of wiping to get a white cloth to come out clean.

I see that the fuel vent clip gets a snap bushings in future steps but I don't see where I'm supposed to drill the hole. Obviously it needs to be done so just did it now. Was difficult to hold while drilling with unibit but figured a way to clamp it to bench with a popsicle stick. Worked out great.

Also drilled the holes for the fuel return line in the inboard rib using the VA-140 bung as a template.

Then started dimpling the skin. Handling everything with gloves after initial cleaning. Was almost done with the skin and had the. Skin in a fairly precarious position. I went to adjust the skin while the DRDT2 was still engaged in the previous hole. I'd done this before without problem, but this time the DRDT2 sprung up out of the hole rebounded and came back down on the skin. It made a little pimple, but didn't pierce the skin. It's going to be ok, but whew.

6/6 am: scuffed faying surfaces of all the ribs and cleaned with acetone. starting to dimple. Countersunk the holes in the T-1005 attach bracket. Not specifically called out, but it is 0.063" so it wasn't going to dimple. Starting to seem more instances of Van's assuming you'll figure it out by now.

6/7 am: finished all the dimpling before work. I think we are ready to start assembly.

  Jun 02, 2022     18-4 & 18-5: Chipping away at tanks - (5.0 hours)       Category: 18: Fuel Tank

Installed the back baffle and zee brackets for right tank. Countersunk the holes in the skin and the zee brackets.

Trying to think about what I will prime prior to assembly. Probably prime the zee brackets, the outside of the back baffle, and the inboard attach bracket that is outside the limits of the tank. Once tank is all assembled, I will spray everything with a topcoat of EcoPoxy. I don't trust that EcoPrime is going to hold up well to fuel. I will probably hold off the EcoPoxy until I have the fuselage kit - I was planning to use it in the tunnel and below the floor pans too.

6/3: after some contemplation and looking at some other peoples logs, I decided to prime the zee brackets and the inboard portion of the attach bracket. I masked off the face of the zee brackets that contacts the rear baffle where there should be some proseal bond.

Went ahead and fabricated the zee brackets for the left tank and then prepped and primed the parts for both the left and right tank.

6/4: Installed nut plates on the zee brackets and then installled nut plates with spacers and installed bearings on the inboard attach brackets. It was really hard to keep the thin shims from distorting quite a bit during dimple and riveting. Hope it doesn't affect the fit of the fairing.

Countersunk holes in fuel caps. Need to research some fuel cap options before I commit to these. Fellow on Facebook is making flanges for the nicer aluminum caps. Might go that route.

I see that the fuel vent clip gets a snap bushings in future steps but I don't see where I'm supposed to drill the hole. Obviously it needs to be done so just did it now. Was difficult to hold while drilling with unibit but figured a way to clamp it to bench with a popsicle stick. Worked out great.

Can of proseal from ACS arrived today so that will let me start on some ribs.

6/5: Drilled the hole for the fuel return line using the VA-140 bing as a template.

Disassembled right tank and scuffed the rivet lines on the skins. I've seen folks tape off the limits, but that seems like overkill. I traced the areas in sharpie prior to disassembly and then just scuffed to erase the marks. I deliberately went well outside the mark to get good bond in the fillet areas. Scuffed then wiped with acetone until clean. Took a lot of wiping to get a white cloth to come out clean.

Then started dimpling the skin. Was almost done with the skin and had the. Skin in a fairly precarious position. I went to adjust the skin while the DRDT2 was still engaged in the previous hole. I'd done this before without problem, but this time the DRDT2 sprung up out of the hole rebounded and came back down on the skin. It made a little pimple, but didn't pierce the akin. It's going to be ok, but whew.

  May 30, 2022     18-2 & 18-3: Starting on fuel tanks - (3.2 hours)       Category: 18: Fuel Tank

Got started on the fuel tanks. I may bounce around to other items, but figured I should at least get one tank going.

Fluted and straightened the ribs. Fabricated the stiffeners and zee brackets for the right tank. Cleco'd the stiffeners and adjust the in board ones per the plans. Cleco'd all the ribs in place and installed the j channel. Match drilled the j channel.

Need to buy proseal and order extra VA-141s for fuel returns. Not planning on EFII, but want to include the return lines now just in case I change my mind.