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Tanks resume…

May 15th, 2014 No comments

No pictures, but I did make some progress tonight.

I was out in the shop doing other things and just decided to clean out 1/4 of the rivet holes in preparation for riveting.

I basically removed the clecos from every other hole in a line, passed a #40 bit through them by hand, and then chased the dimple with a countersink by hand.

I still need to scrape a little on the inside the tank for each dimple and then hit each with MEK to clean off scraps and human oils.

I need to repeat this on the other 3 remaining sides of the tanks and then I think I will be ready to final rivet them.

Progress is progress, one rivet at a time.

Categories: Tanks

Tank Ribs Sealed to Skin

September 2nd, 2013 No comments
Tanks Sealed and Setting

Tanks Sealed and Setting

Well, I finally bit the bullet and decided to get the ribs installed/sealed in the tank skins. For some time, I have not been enthused about the prospect. I just do not like ProSeal. Then again, I do not like caulking, drywall finishing, epoxying, or any other fluid type process (to include biologic). ProSeal does come with some distaste in the RV world, so I feel OK not being alone.

Some time ago, I read a thread on VansAirforce.net written by a guy named Rick Galati addressing this very ProSeal myth. I reread it several times leading up to just knocking it out. His general idea is to butter up the ribs, cleco them 100%, let set a few days, then rivet them together. This allows you to let the majority of the ProSeal get tacky or even light set, then all you have to worry about is wet setting the rivets (placing a dab of sealant in the countersink and inserting the rivet), then coming back and encapsulating the shop head in sealant to finish the task. You can click the link to get right to the thread.

At Least These Look Good

At Least These Look Good

After getting up the confidence and after taking care of a few household tasks, I headed out to the shop. I gathered all the materials, counted out the number of clecos, and cleaned all the parts. It was now or never. Armed with some 6 oz. ProSeal cartridges, a Semco sealant gun borrowed from another builder, and a ton of gloves, I started in on the right tank.

Process as follows:

  1. First, butter up the flange of a rib, then cleco it to the skin on the top with 5 clecos.
  2. Once all ribs are clamped into the skin, slide the skin into the cradle and begin clecoing the bottom starting at the leading edge with 5 clecos.
  3. Then cleco the rest of the holes until all are filled.
    1. This causes some squeeze out of the sealant to occur.
  4. Waited for about 5 minutes and then begin to smooth the squeeze out with a popsicle stick or in my case, a sealant spoon (donated to me by the same builder friend I borrowed the Semco gun from, THANKS TODD!).
    1. In places where the squeeze out is a little light, simply apply more ProSeal where needed (this is easy with the semco gun) and smooth.

Turns out, the 6 oz. cartridge size is just enough to do one tank worth of ribs. I blew through a couple of towels as I smoothed the fillets and wiped that sealant spoon. ProSeal is MESSY!

As you can see from the above picture, the web side of the ribs have pretty nice looking fillets. The flange side…well, not so much. Are they sealed though? I think so, and did all I could to make sure there was a continuous seal all around the flange. The sealant is especially messy at the nose of the ribs. The trick is to seal, not make pretty. Since this is not something anyone can see, I think it will be just fine. The true artists can do a great job, I just don’t want to have any leaks. Any light spots discovered later can be managed with more sealant after it is all set and before the baffle is sealed into place.

I repeated the process with the left tank. There was 1 rib flange at the forward most top hole that was not sitting right. Rather than take apart the whole tank to get at it, I decided to rivet that hole right away. I took a piece of flexible fuel line (rc airplane type) and placed it over a MEK cleaned rivet tail and set it. It pulled the flange right into place.

I Am Not Showing The Flange Side! ;-)

I Am Not Showing The Flange Side! 😉

Once both tanks were done, I taped over each end of the rib to pull the skin closer together. The bend in the skin makes it splay away from the rib flange. Not a problem once the baffle is installed, but at this stage, I just felt better pulling them in to set the flanges where they should be while the sealant cured.

Next up, I need to buy some more sealant and get ready to rivet the tanks final. I am glad to have this step behind me. Please…NO LEAKS!

Categories: Tanks

More Sealant Tasks Done

June 19th, 2013 No comments
Inboard Rib Penetrations and Other Tasks

Inboard Rib Penetrations and Other Tasks

With the work completed Monday, I was essentially ready to take care of the last of the little sealant tasks to be done before the “big smears” are to start.

Last night I had CAP meetings and then ended up hanging out at the airport, helping a friend rivet a bulkhead on a Harmon Rocket. Once that was done it was too late to start any sealing in my shop.

So tonight, I devised a plan of attack to maximize my success and knock out these little tasks. I started by prepping the T-410’s for the outboard end ribs. The manual clearly warns you about installing these on the inboard ribs, but the clearance on the outboard is just fine. Riveting them now is far easier. I scuffed them up and cleaned them off with MEK. I then grabbed 12 AN470AD4-5’s and soaked them in MEK for a bit.

I then loaded all the AN fittings and spacers into a jar of MEK to give them a good cleaning. I wiped both the inboard and outboard ribs down and from that point on, did not touch any parts without gloves on.

I grabbed a 6oz cartridge of ProSeal and mixed away. I first sealed the T-410s to the outboard ribs. I 100% clecoed them on and set them to the side for a bit to allow them to squeeze out. Then I went to sealing the fittings and spacers to the inboard ribs. I first put a thin layer of sealant on the shoulder of the AN fittings, inserted them into their locations and then, after smearing the backside of the spacer with a coat of ProSeal, placed it over the fitting. I then put a small fillet at the fitting on the top of the spacer and then threaded the nut on. This caused a thin gasket of ProSeal to squeeze out from under the nut. I torqued the nut to spec and then repeated this process for the other three fittings.

Next up were the BNC fittings for the fuel senders. I was tempted to put the same thin layer on the shoulder, but the barrel of the BNC needs good continuity between it and the tank. I decided to insert them dry, then tighten the nut, and then seal them good from the backside. With a good “Hershey Kiss” of sealant, it should not leak. Once installed, I did just that, gave it a healthy covering to extend well over the wire and solder joint. It really does look like a black “Hershey Kiss” when you are done.

Once the fittings and BNC’s were in, I went back to the outboard ribs and squeezed the rivets. I then proceeded to “mill” all the sealant. I made nice fillets around the edges of the T-410’s, cleaned off any over done squeeze out, and then covered each shop head with sealant. The manufactured heads will be covered once the rib is attached to the skin, so I cleaned the outside of the rib completely. I then went back to all the fittings and created nice fillets around all the edges of the spacers and nuts. Once that was done, they were nearly covered completely, so I just decided to finish it off. Should not leak here.

Lastly, I hit the outboard Capacitance Fuel Sender plates, where the wire/ring terminal are bolted on, with sealant on the bolt/screw/terminal/nut, as well as sealing off were the wire enters the ring terminal. I think the purpose is for providing good strain relief for the wire. Some say it is to keep fuel from wicking into the strands of the wire. Either way, mission accomplished.

Once all that was done, I went back and cleaned up all the strings of sealant left on parts, cleaned up my tools, and called it a night. These parts will sit for some time while I do the rest of the tasks needed on the tanks, so the sealant should be well cured by the time I mess with them.

Next up…Tank Assembly!

Categories: Tanks

While the Cat is Away…

June 17th, 2013 No comments
Parts Prepped and Ready for Sealant

Parts Prepped and Ready for Sealant

My wife and kiddo’s took off today for the week to play crew support for a scout hiking trip in southern Utah. She left VERY early. Since there was no way I was going to go back to sleep, I headed into the office. I figured I would get the work day knocked out and head to my empty home early. While the “get home early” never happened, I did get out to the shop for a bit.

I prepped the inboard rib penetration spots for sealant. I first scuffed all the locations where the vent and vapor return fittings, and fuel sender connectors would go. Then I cleaned up the spacers by deburring the edges and scuffed the faces.

Lastly, I cleaned up the Capacitance Fuel Probe BNC’s and wires to remove greases, finger slime, and other debris. Once that was done…I was ready for sealant. Not tonight however.

 

Categories: Tanks

Right Tank Sealing Work Starts

June 8th, 2013 No comments
Proof for the FAA.

Proof for the FAA.

OK…so I hate ProSeal. I know I shouldn’t, but I do. I despise the sticky, gooey, snot like stuff. That said, I need to get moving on the plane again. A fellow builder/owner has been hassling me (actually giving good moral support) to get going again as well. Does not help that he let me borrow his sealant gun back in November and I have been holding it captive. We chatted this week again and he darn near pushed me into the shop verbally right then. Thanks Todd!

This weekend had a few items on the “To-DO” list. First, we planned to go hiking as a family EARLY Saturday AM. Apparently the powers that be decided otherwise as the regulator for the drivers side window in our family hauler decided to catastrophically fail Friday night. My Saturday morning turned into a “can I find one” mission and if so, “can I change it out” followup. Fortunately, the dealer did have one, and as much as it pains me to pay more for genuine Honda parts and their associated price, they were local, and I could get the van back in service quick. You got to love Honda engineering. They really seem to think things through from a build and repair standpoint. It was actually a pleasant repair all said and done. I was happy to have the family assault vehicle back in shape.

So with that rewrite of my list, I decided to take a nap, then head out to the shop and see what I could get done. Since buying my original can of B2 ProSeal, it has LONG since expired. My friend Todd had some 1 oz. B2 Semco cartridges he gave me when he lent me his gun. They too had expired a little while ago, but in conversation with him, he said if they mixed up smooth, they should be OK. Did not hurt that they were stored in a cold shop for the last few months. He also gave me some newer 2.5 oz. sized B 1/2 type as well this week. Can you see a trend? Todd really wanted me to make some progress. I also learned that I could purchase some 6 oz. B 1/2 or B2 tubes locally for a decent price.

There has been some debate around the mix as you go or Semco cartridge routes. Both certainly have their advantages and disadvantages. I won’t rehash it here unless asked, but I found that I REALLY liked the gun/cartridge route this time, despite tossing some sealant once I ran out of time. The gun really lets you control where the sealant is going and eliminates the headache of measuring out the parts and making a mess mixing it. It costs a little more to go the gun route, but the convenience seemed very worth it. I think I will borrow the gun from Todd a few more times.

Right Tank Stiffeners Attached

Right Tank Stiffeners Attached

First up were the stiffeners on the bottom of the tank. I masked off the areas with electrical tape after cleaning all the stiffeners and skin with MEK.  I then shot each stiffener with a bead of sealant, smeared it over the whole surface, and then clecoed each in place. I waited a few minutes for squeeze out, then back riveted each and formed the fillets. I used the sealant gun to put a dab over each shop head to eliminate any path for fuel to leak. This took about an hour. I used the 1 oz. B2 tubes that were a little old. They mixed well and the sealant came out nice and smooth. (Update, they cured fine too.)

Right Tank Sump Flange

Right Tank Sump Flange

I then moved on to the sump flange. By then my flying bud, Matt had arrived to kill his boredom. He helped keep my mind off my dislike for the sealant. I smeared the faying surface and clecoed it on. After 5 minutes, came back and was able to use my squeezer and install all these rivets. The shot above is after some serious cleanup. I got a little in the threads of the flange, but I think I can clean it out with a tap or rag later.

This Should (Better Not) Leak!

This Should (Better Not) Leak!

Last, or so I thought, was the filler neck and vent line clip. As you can see, I got a little carried away with the sealant here. I had plenty in the tube and was getting short on tasks I had planned out to accomplish. Needless to say, it should not leak, at least not here. I was able to get the four most outboard rivets with my squeezer, but the rest I back riveted in place one at a time.

Right Tank Filler Neck and Cap from the Outside

Right Tank Filler Neck and Cap from the Outside

Here you can see the flange/cap from the outside. Turned out OK. I have one rivet that appears to be slightly high, but I will likely shave it down. Replacing it would be very difficult now that I have super sealed it. There is a nice bead of sealant around the opening in the skin and each rivet. The deluxe caps sure look nice.

Outboard Tooling Hole Filled and Sealed Inside

Outboard Tooling Hole Filled and Sealed Inside

At this point, I started to clean up stuff. As I was looking around, I remembered that I had some AN470AD6 rivets (again from Todd) that I could use to plug the tooling holes in the outboard ribs. These are big suckers and my squeezer just barely did the job. I put the manufactured head on the inside of the tank to give it the best bearing surface area contact. Once I got it smashed in place, I coated both sides with sealant.

Outboard Tooling Hole Sealed

Outboard Tooling Hole Sealed

Here is the outside of the same. Sealed and covered. Takes care of that hole.

The time was spent, I was tired. So I cleaned up, tossed all the sealant covered rags, gloves, cartridges, and friends out and closed up shop. I will let this sit for a bit to cure and then likely hit the inboard rib penetrations/fittings with sealant. Todd told me he would help me with sealing/riveting the ribs, so I need to get everything else done so he is not held up by my feet dragging. I will get through these tanks eventually.

Categories: Tanks

Back in the Saddle Again

April 25th, 2013 No comments
Tank Skin Woes

Tank Skin Woes

Time to fess up. I have been a little discouraged and busy and the plane has taken a hit as far as work. I was chugging along with the tanks last year when I read a post on VAF that talked about the #8 screw dimples cracking on tank skins. I thought that was weird as I did not remember that happening on mine. So I went out to the shop to confirm and to my dismay, I was also a victim. I was crushed. I had just Pro Sealed the stiffeners, fuel flange, and drain fitting on one skin and it was all for naught?

I stewed about it, beat my head against the wall, groaned a bit, and overall just was deflated. May seem like an overreaction to some, but it was a little disheartening. It did not help that the number of dimples that seemed to be affected was pretty high by my standards. So I turned out the lights and walked away. That was months ago. Then the holidays hit, weather got cold, life got busy.

I discussed my options with some fellow builders. One even asked his engineering department about it and they had some suggestions. I contemplated ordering new skins and undoing the filler flange (as that part is as much as a skin) and starting over. Other options were presented, so I mulled them all over. Vans said that this can happen, but that they would build on and that they would likely not move…much. They also suggested that the hole could be drilled a few thousandths bigger to catch the crack, but not to really worry about it. Right…do they know who they are talking to here? The friends engineering department agreed with Vans on the enlarging the hole. The bearing and strength is at the dimple shoulder, not the hole, so it was inconsequential to the structure what the hole size was as long as the head of the screw had a good material base to sandwich.

Ultimately, I decided I would give enlarging the holes a shot, and if all else failed, I could always get new skins. One of my builder friends tossed me a 0.2081″ double margin bit and said, “start here.” Now it was a matter of just doing it.

Today, a fellow builder from Colorado posted on VAF that he would be in town and would like to visit another project. Reading that, and thinking what the heck, I tossed out an invitation to visit. This would at least get me out to the shop and talking RV’s. We set up a time and I went out to the shop after work figuring that I would at least clean up the shop for visitors. Once I was out there, I decided to try dressing one hole and see what it looked like. Nicely enough, it actually took the crack out and once I deburred it and cleaned it up, looked OK. So I moved on to the next hole. After an hour, I had dressed and cleaned all of the problem holes. For the most part, they all cleaned up nicely. There a still a few that have a remnant of a crack, but with a needle file, could easily be polished out. The hole would look a little strange, but would never be visible under the screw.

For those that are wondering about the size of the hole still, rest assured, even after drilling out what was originally a 0.166″ hole, that was then stretched bigger by the dimple die, to 0.2081″, the material left is still slightly more than the shoulder of the spar countersink (remember how they knife edge in the spar). So all I removed was the overhanging material from the stack-up of the tank skin, spar web, and nut plate. I also made a test piece from 0.032″ to confirm how it seats in the spar dimples and to confirm the holes and can report that it works and looks great. So perhaps I dodged a bullet here.

What did I learn here?

  1. Don’t use a #19 bit for the pilot holes on a #8 screw dimple. Use a #17 or even a #16 bit. The amount of material stretching is too much on the #19 hole. The pilot will still center on the die as you compress them and the hole stretches to a hole bigger than the #19.
  2. Make sure to back the holes you are enlarging with a piece of wood behind them. When I enlarged the skin holes, I just let the bit run free in the hole. I think this allowed the bit to wander and chatter.
  3. Take your time on larger dimples.

In the end, I think I have good skins and will build on. Other than this confession, you will not know it had to be fixed, and the plane will never see the difference in strength.

After it was all said and done, my visitor, rockwoodrv9a, stopped by and we chatted for an hour or so. Real nice Nice guy! I hope he found the visit worth while. I did, as it got me working again. Now to keep the momentum going.

 

Categories: Tanks

Left Tank ProSeal Begun

November 12th, 2012 No comments

Left Stiffeners Goop On

So…the time came to break out the ProSeal and start gooping up parts. I can now see why people do not like this stage of the build. I pulled out my digital scale and the rest of my supplies and started going to town.

First things first. I swished some rivets in MEK to get the manufacturing oils, etc. off them. Then I taped both stiffener rivet lines in using my back rivet tape. Then I set each stiffener in place to use as a guide for the electrical tape masking I did on either side and then in between. Don’t make the mistake I made next. I re-wiped the lines clean with MEK. Not a big deal, but it does soften the adhesive on the tape a little. I only noticed it after I peeled it off once the sealant was on.

With the stiffener locations masked off, it was time to mix up a batch and get going. I mixed up 40 gram of white and 4 grams of black to start (10:1). Turns out it was not enough, so I will try 60/6 next tank.

With it mixed up, I slathered the stiffener bottom with a tongue depressor and then pushed over the rivets. I then used my back rivet set/plate and started smashing away. Once the matching pair of stiffeners at each location was riveted on, I smoothed out the excess with a popsicle stick to form fillets. I noticed that on the backside of the stiffener, there was not enough that squeezed out to make a nice fillet, so I tried to add some with the popsicle stick which ended up making a heck of a mess instead.

The trick I then used was to grab one of the free oral syringes I acquired and after cleaning it with MEK, I filled it with ProSeal and was able to apply a bead along the back of the stiffener to make a really nice fillet. The front and sides were fine as is.

As for adding the bit over the shop heads, I also ended up using the syringe here. It made it easy to put sealant where it needed to be.

This took some time to complete…almost to an embarrassing degree. I think now that I have a “method” it should go faster.

Internal Shot of Left Drain

Next up I tackled the drain flange. I smeared the ProSeal on the face and clecoed it on. I was able to get to all these rivets with a squeezer. You need to cover the shop heads here too. Just insure that you do no block the path for water to get around the blobs. I think mine are just fine.

External Shot of Left Drain

Here is a shot of the external side of the flange after A LOT of cleaning up.

Interior Shot of Left Filler Neck with Rivet Callouts

The last item I wanted to attack today was the filler neck. I gooped it up nicely and clecoed it on. I was able to get to the four outboard rivets with a squeezer, but the rest are too far away. I decided to back rivet them and they turned out OK. Do not forget the vent line clip and make sure you put it on the leading edge side of the flange. Since these are the deluxe caps, I had to use various different size rivets for the perimeter. This is because the flange is a machined part that is flat on the bottom and curved for the contour of the tank. You can see my callouts above on the lengths.

External Shot of Left Tank Filler Neck

Here is a shot of the Filler Neck from the exterior after some significant clean up. Looks good to me. For some reason the dimples on at the 0230 and 0830 positions look weird in this picture, but they are just right. The picture is playing weird with the lights.

Once all this was done, I was cooked for the day. I cleaned up the shop, threw away what seemed like 20 pairs of nitrile gloves and all the gooped up cups, plates, sticks and etc. I was surprised how clean I really was after it was all said and done, but I have plenty more sealing to do that will likely prove messy in the end. 🙂

 

Categories: Tanks

ProSeal Supplies Stocked

November 6th, 2012 No comments

ProSeal Gear

Boss sent me home from work. I guess I was not well enough. On the way, I picked up my tank assembly supplies.

  1. 9 oz. Plastic Cups for mixing
  2. Tongue Depressors for spreading
  3. Popsicle Sticks for mixing and filleting
  4. Electrical Tape for masking
  5. Paper Plates for placing messy tools on
  6. MEK for cleaning parts
  7. Syringes for squirting sealant where needed
  8. ProSeal to seal

Looks like I am ready to start. I may this weekend, but my wife will be out of town, so I may have to wait.

I spent the day resting once I got home.

Categories: Tanks

Home Sick and Stir Crazy…Prep Parts Then

November 5th, 2012 No comments

Fabricated Vent Line Clips

I called in sick today…and trust me…I was. I have been on the decline for a few days with a cold and figured it was not a good idea to get everyone else sick at the office. However, I rarely can sit still for too long and by afternoon I figured I would see what little tasks I could knock out on the here’s and there’s of the tanks. I swear, I really was sick…ask my wife.

Next up on the to do list was to fabricate the small clips that get installed with the fuel filler flange that hold the outboard end of the vent line. They are simply made out of some scrap 0.025″ sheet laying around. I think they turned out OK.

Next I drilled the outboard T-410 reinforcement plates to the outboard tank ribs. The instructions say that three or four AD4 rivets are OK, but I opted to use 6 like the inboard T-410’s just to keep the nose of the ribs really flat.

I also cut the wire for the capacitive senders and attached the BNC connectors and the terminals per the directions. They seem really secure. I did solder the terminals as well.

Then I deburred and dimpled all the ribs for both tanks and scuffed the faying surfaces that will eventually get sealant. I did the same to the stiffeners.

Nearly ProSeal Time

By the end of the night, I was still feeling lousy, but was able to feel like the day was not a complete waste. I was left with the pile of parts above ready for assembly. At this point, it is ProSeal time. I think I will wait until feeling better to start working with that stuff.

Categories: Tanks

Dimpled and Scuffed Tank Skins

November 3rd, 2012 No comments

Scuffed and Dimpled

After mowing the lawn for the last time this year…I hope, I headed out to the shop to knock out some more work. End result, tank skins are all dimpled and scuffed and ready for ProSeal. It may not seem like a lot done, but it did take a lot of work. I had to remove the exterior vinyl from the rivet lines, deburr all the holes, dimple, scuff and clean them up with MEK. All in all a multi hour adventure.

These tanks have a LOT of holes. I had a blister in the palm of my hand from the DRDT-2 handle by the second skin. The time is drawing near for ProSeal….yippy! 🙁

Categories: Tanks

Inboard Rib Plumbing Penetrations Done

October 22nd, 2012 No comments

Inside the Inboard Tank Ribs

After giving some (OK, too much) thought to where I wanted to run the vapor return fitting, I finally settled on the upper part of the forward stamped stiffening ring. I opted for simplicity, so I also drilled a hole in each interior tank rib in the same location as the bulkhead fitting. This way the return fuel will dump into the most outboard tank bay and get cooled down by the rest of the fuel before being picked up again. Additionally, the return line will simply be a straight piece of tubing through the tank.

The holes were all 7/16ths for the vent and vapor return lines. The BNC hole for the capacitive senders are 3/8ths.

Outside the Inboard Tank Ribs

At this point I am ready to deburr all the rib holes, skin holes, dimple, scuff, and generally get ready to break out the sealant and get to final assembly of the tanks. Here you can see the penetrations from the exterior of the tank.

After getting this prep done, I cleaned up the shop and basically got things in order. It may be a couple of days until the next build session. Hopefully I will be done sealing tanks by Thanksgiving.

Categories: Tanks

Countersunk Cap Flanges, Plumbing Work

October 20th, 2012 No comments

Countersunk Cap Flanges

Spent yesterday at my Grandmothers funeral. She truly was a great lady in life. Family was still in town, but had not arrived at the house yet so I snuck out to the shop to see what could be done.

I was able to countersink the flanges of the fuel caps to accept the skin dimples. If you look at the full size photo (just click it) you can see the varying thickness of the flange that I mentioned in the last log entry. This was pretty painless. I love having a countersink cage for each size. I can set and forget for a certain setting. These are now ready for sealing and installation onto the tanks.

Drilled the Left Tanks Capacitive and Vent Penetrations

Next I was able to locate the vent and capacitive sender connection locations on the Left Tank. I still need to figure out where I want to put the vapor return line for the possible EFI setup. The washer you see in this picture is likely the location I will use. I also thought about putting it where the mark is on the rib inside the stiffening circle you see there. I do not know…but will decide in the next few days.

That was all that I had time for, so I closed up shop for the weekend.

Categories: Tanks

Drilled Fuel Caps

October 18th, 2012 No comments

Drilled the Fuel Cap Flanges

This week has been a little hectic as my Grandmother passed away last Friday. With all the ramping up to the funeral and family coming into town, time is short. I was able to get out to the shop and at least get the fuel cap flanges clamped into place and drilled. As you can see, I am using the “deluxe” locking caps. I have heard, and experienced, the stock caps. They are tough to open. These however are very nice and smooth in operation. I think they look nicer too.

The stock cap flanges are bent to match the curvature of the tank skin. These deluxe caps are machined to the curvature. The difference in the build is that you have to use all different length rivets on the deluxe where the same rivet length is used on the stock.

I centered the cap in the hole, clamped it in place and drilled each rivet hole. As I drilled one, I clecoed it, then went 180° and drilled that and clecoed. I followed a star pattern like you would when installing lug nuts on a wheel. Once complete, I checked the alignment again. Not that I could do anything about it, but for sanity sake. The look good to me. That was all I could get done for the day.

Categories: Tanks