Time to attach all of the platenuts/nutplates to the spar web. Nothing too difficult, just repetitive. Start by upsizing the predrilled holes for the nutplates to #40 to accept the AN3 screws. Simple enough and glad I taped off all the openings as it generates a ton of shavings. With the holes opened up, you need to countersink each one to accept an AN426 3-3.5 rivet. Key is to get the depth just right, not too deep but not too shallow. The skins from the fuel tank will sit on top of the spar web in this area and any rivet head sticking up will make the skin not want to sit flush. After practicing a few holes on a scrap piece I had the countersink dialed in and again just a matter of making good countersink holes down the length of the spar web. Again this generates a lot of shavings so I vacuumed up the shavings quite often as it makes a mess. With the countersinking done, you can add the K1100-8 nutplates to the bottom side of the spar web flange and secure each on with a single cleco. This lets you line up the other attach hole and put a 3-3.5 rivet in it. I used the pneumatic squeezer to set each rivet in place. With that done the clecos can be removed and the nutplates are held in place. Now it's time to countersink the larger screw hole. Before doing that, I needed to get the larger countersink set up to make the proper depth of cut. The platenut will host a #8 screw which is placed through a dimpled skin from the fuel tank. So you will have a dimple sitting inside a countersunk hole that leads into a platenut. Somewhat important to get the depth of the countersink correct to make sure everything nests inside themselves properly. To do that I tried countersinking a few holes in the scrap material. Unfortunately the C/S bit would immediately start chattering back and forth slightly in the hole as the pilot of the C/S bit had nothing to hold it steady. So I tried making a guide out of another piece of scrap and even that really didn't help. So it wasn't feeling very optimistic at first. Then I decided to actually just use a platenut and practice on that. After setting it up, I was able to drill a very nice countersunk hole, indeed as the Vans instructions indicate, the opening in the platenut will act a guide for the countersink bit pilot and allow you to make a nice hole without the chattering. I kept experimenting with the depth and a #8 screw until I had it where I wanted. I double checked the cut dimensions using a caliper and referencing the dimensions given in the RV-14 plans. Everything was in limits and this should result in good holes once I drill them into the spar web. As I was experimenting with the practice platenut, I noticed that if the AN426 rivet heads sat a little high in their countersunk holes, this had a tendency to make the skin not sit completely flush with the part. So I ended up checking all those nutplates that I just riveted and decided to drill out the rivets on a good portion of them. I then went back and used the #40 countersink to increase the depth of those holes just slightly so that the rivet will sit absolutely flush to the spar web flange. The AN426-3 rivets are easy to remove fortunately. Replaced the rivets that were sitting slightly proud and called it a night. Also in this series of work I started setting up the process to make the spacers used on the tie down supports. The spacers are made from a 1/4" aluminum bar that comes with the wing kit. I marked and center punched the locations for the holes to be cutout and will use a hole saw on my drill press to cut them out when I get to that point.