A few folks read a post I made a couple of weeks ago about upgrading the EFIS AHRS and Autopilot in my RV-8. Some will remember this photo of the back of the panel where I talked about using lacing cord to replace all the cable ties that made the installation a bit ?clunky?.
But few know that I got a call from old ?clipped-digit? (Stein) at Steinair, complimenting me on my lacing and harassing me about my plumbing! Yup, it was and always has been a bit awful ? too much tubing, and all those gosh-awful Nyloseal fasteners. He challenged me to do better, and before I knew it, a set of those cool ?push-on? pitot/static fittings were on their way to Houston. I felt like a kid with a new erector set for Christmas ? all sorts of cool parts that can go together in a lot of different ways.
The most amazing thing about these easy-to-use fittings is that they cost just about the same as the nylon fittings you order from ACS (In my book, the aviation Nyloseal fittings are just way overpriced when you consider that they probably cost pennies to make?). I had to order a few to finish my upgrade, and after I?d ordered them, I happened on Stein?s pricing for the push-ons, and kicked myself for not switching over. It really won?t cost but a couple dollars more to do an airplane with the modern connectors, and they are so much easier to use. Oh, the other cool thing Stein has ? two different colors of tubing! No more wondering if that tube you are seeing through one eye while upside-down under the panel is Pitot or Static. I arbitrarily used Orange for Pitot and Clear(white) for Static. Pretty hard to get that backwards.
One of the reasons that I had so much tubing back there was because my panel is removable, and I wanted to have service loops so I could get the panel in my lap before disconnecting everything. The funny part is that, as a linear thinker, I had a very logical process for connecting the system. The pitot/static lines come up the left side of the airplane, behind the panel. So I used service loops to connect them to the airspeed and autopilot on the left side of the panel, then crossed over to the right side for the altimeter and VSI, and then had service loops to go back to the forward-mounted AHRS. Got the critical backups first, then the fancy stuff. Makes sense, right? Well, it seemed to five years ago when I built it. But looking at it again, I realized that I had way more plumbing than I needed. Why the heck have two sets of service loops when the AHRS is bolted to the ship?!
For this go-around, I took the ship?s plumbing direct to two manifolds, from which comes a line for each AHRS, then a service loop for each (pitot and static) to the panel, connecting to ?Y?s? to the backup instruments. Here is the new back of the panel:
And here is the ship?s plumbing to the AHRS (you can see the connection on the manifold for the panel service loop on the left):
When we visited Stein?s place on our Christmas trip, he showed me the two tricks to making these things work. First, you need a clean, square cut end on the tubing ? he sells a cheap cutter that does this. Second, as you push the tubing in, there are two distinct ?clicks? you will feel. The first is a tempting place to stop ? it feels like it has connected ? but it has just touched the O-ring. Push farther - the tubing will go in through the O-ring, and you will feel the full stop position ? now it is nicely seated and leak free. I took the plane up with its new system and all worked well from the get-go.
I?m not going back to the Nyloseal systems ? I have had enough fun trying to get good seals with a variety of tubing. These new connectors (and boy, I really like the two colors of tubing!) are easy to connect and easy to take apart. Definitely worth the time it took me to retrofit (about two hours), and more than worth it on a new build ? at leats for me.
Paul
But few know that I got a call from old ?clipped-digit? (Stein) at Steinair, complimenting me on my lacing and harassing me about my plumbing! Yup, it was and always has been a bit awful ? too much tubing, and all those gosh-awful Nyloseal fasteners. He challenged me to do better, and before I knew it, a set of those cool ?push-on? pitot/static fittings were on their way to Houston. I felt like a kid with a new erector set for Christmas ? all sorts of cool parts that can go together in a lot of different ways.
The most amazing thing about these easy-to-use fittings is that they cost just about the same as the nylon fittings you order from ACS (In my book, the aviation Nyloseal fittings are just way overpriced when you consider that they probably cost pennies to make?). I had to order a few to finish my upgrade, and after I?d ordered them, I happened on Stein?s pricing for the push-ons, and kicked myself for not switching over. It really won?t cost but a couple dollars more to do an airplane with the modern connectors, and they are so much easier to use. Oh, the other cool thing Stein has ? two different colors of tubing! No more wondering if that tube you are seeing through one eye while upside-down under the panel is Pitot or Static. I arbitrarily used Orange for Pitot and Clear(white) for Static. Pretty hard to get that backwards.
One of the reasons that I had so much tubing back there was because my panel is removable, and I wanted to have service loops so I could get the panel in my lap before disconnecting everything. The funny part is that, as a linear thinker, I had a very logical process for connecting the system. The pitot/static lines come up the left side of the airplane, behind the panel. So I used service loops to connect them to the airspeed and autopilot on the left side of the panel, then crossed over to the right side for the altimeter and VSI, and then had service loops to go back to the forward-mounted AHRS. Got the critical backups first, then the fancy stuff. Makes sense, right? Well, it seemed to five years ago when I built it. But looking at it again, I realized that I had way more plumbing than I needed. Why the heck have two sets of service loops when the AHRS is bolted to the ship?!
For this go-around, I took the ship?s plumbing direct to two manifolds, from which comes a line for each AHRS, then a service loop for each (pitot and static) to the panel, connecting to ?Y?s? to the backup instruments. Here is the new back of the panel:
And here is the ship?s plumbing to the AHRS (you can see the connection on the manifold for the panel service loop on the left):
When we visited Stein?s place on our Christmas trip, he showed me the two tricks to making these things work. First, you need a clean, square cut end on the tubing ? he sells a cheap cutter that does this. Second, as you push the tubing in, there are two distinct ?clicks? you will feel. The first is a tempting place to stop ? it feels like it has connected ? but it has just touched the O-ring. Push farther - the tubing will go in through the O-ring, and you will feel the full stop position ? now it is nicely seated and leak free. I took the plane up with its new system and all worked well from the get-go.
I?m not going back to the Nyloseal systems ? I have had enough fun trying to get good seals with a variety of tubing. These new connectors (and boy, I really like the two colors of tubing!) are easy to connect and easy to take apart. Definitely worth the time it took me to retrofit (about two hours), and more than worth it on a new build ? at leats for me.
Paul
