Mark I love your videos, very helpful. I'm currently building a CH 750 STOL I have an added tip for cutting holes in Fuel tanks that I tried when I did mine the other day. I took my shop vac and plugged in the exhaust side of Vacuum into the filler hole. wrapped some tape around it, turned it on and used a fly cutter to cut the 59 mm hole The inside pressure kept all the fillings out of the tank. Magic . Yes I rinsed the tank out to be sure it was free of debris. Cheers Andrew Atkins in Ontario Canada
Burnout sneaks up on you and dishes out a really hard body check into the boards. (Canadian, eh) It happens in every profession I know. Thanks for reminding us all about how to deal with that. I'm truly enjoying this build. Keep up the great work.
This is an excellent video, not just on the sender install but touching on the burnout factor, a subject that get's overlooked when building, especially if you are doing everything all by yourself, sometimes it's just better to stop and walk away for a bit, before mistakes are made and needless money has to be spent twice. Keep up the fantastic job Mark.
I just recently swapped-out my leaking VDO senders (9 years old) for the Stewart Warner senders. I had the exact same issue as you did - the SW senders seemed stiff and didn't move with small additions of fuel as I calibrated my senders. However, I found that I could rock the wings vigorously and the senders would settle on the new fuel level. A flexible "snake" video camera is helpful to peek inside and ensure the sender is floating on the fuel. Also, similar to your experience, I found it was a non-issue once I started flying again - the senders either loosened-up or the vibration helps them move - they now work great and are extremely accurate! However, there are 2 critical differences between the VDO and SW senders! The VDO's plastic insulator for the center electrode deteriorates - mine were crumbling like chalk after only 9 years! I think sealing them in Proseal inside and out as you did might help, but who knows? I also suspect that mounting them on top of the tank as you did where the sender is not continuously bathed in fuel (vs the side of the tank mounting) will promote longevity. Secondly, the SW senders use a "thick film" resistor for long life/durability. This technology is used for approved senders for certified aircraft while the VDO sender appears to have a typical wire-wound resistor board that is mechanically rubbed by the sender's arm. A prominent EAB expert who writes for a major magazone told me he used those SW senders in his Van's RV and they were working great 25 years later! BTW, Van's recommends just using Proseal for the SW senders and deleting the rubber gasket - apparently the Proseal alone is quite sufficient . However, I suspect the way you applied Proseal both to the tank hole's rim and the outside of the VDO sender and gasket will work great. Another excellent video! Your attention to detail and explanations not only how to do things but why you did it the way you did are extremely helpful!
Thanks Paul. I really wanted this channel to helpful to more than just Zenith builders. Hopefully people can learn a tidbit or two no matter which airplane they are building.
Love your videos. You may know this but didn't want to talk about it, but you can check the spec sheet for the seal to see the class and application time of the seal. When I taught sealing at the Boeing Company we covered this in excruciating detail. An example would be Class "B" with an application time of 1/2 hour. This means that it is a medium thick seal and you have 30 minutes from the time you mix it until the seal is applied to the surface. Another would be class "C" 20. Thicker seal but an application time of 20 hours. It looked like you used this: 3M™ AEROSPACE AC-350 CLASS B-1/2 - 25 GRAM KIT and you can see the time is 30 minutes.
@3:06 ... and a sledge hammer and a chainsaw and an ax... I'm like uh? but he said is so seriously that I had to go back 🤣 (the no showing the face part helps)
I really enjoy your videos. They are very helpful as I build my SD. Did you shorten the arm of the sender? As I get ready to place mine in the tanks it seems shortening it by an inch or so would allow full travel.
No disposable surgical gloves when working with the pro seal? You’re braver than most builders. Great videos - thanks for all the time and effort that goes into making them.
No. There are no instructions at all for the senders. This is where you have to use common sense. Don’t tighten them so much that you’re completely distorting the rubber gasket.
In my opinion yes. First I’m not sure how the thread sealant would react to fuel. Secondly, I think the ProSeal around the screws will prevent them from turning loose.
So, Proseal on the mating surface between the rubber seal and the tank...got it Do you put proseal on the mating surface between the rubber seal and the fuel sender ??
Awesome video again! My fuel senders (exactly the same as yours) came with 2 rubber seals per sender. Are those extra (or for a Volkswagen) or do some people put a rubber seal between the tank and the inside ring? Seems like that would be hard to do.
Hey Mark! I'm not quite visualizing how the ground wire is making a good connection to anything other than the sender mounting collar? Is that all that's required? After your experiences , i think I'll stick with the senders from Zenith. Thanks , Blue Skies!
Another way would be to get a metal hole punch from GREENLEE or Chinese cheep one since you will only use it one time. You drill a small hole and just tighten a nut till the circle pops out of the sheet metal. The China ones from Ali Express are good for building a single plane.
How would you get the male punch part in the tank? I don’t see how that would work because to use those punches, you have to have access to both sides of the part you want to cut. They are great for punching holes in a firewall!
@@KitplaneEnthusiast The ones I had at work just like the fuel sender. There was a notch is the lower half to get it in and you get 75% of the hole then spin to get the rest. The ones at the place I worked were GreenLee.
Another thought would be to use a small router with a collet and a template out of plywood. Probably what I would do since I already have a router. Just wondering if there is a better way. Love the build!
@@KitplaneEnthusiast www.infinitytools.com/blog/2014/02/14/a-template-that-wont-put-a-hole-in-your-wallet/ A trim router would work well for this, you can also make your own and use a bit with a bearing on it to follow the pattern.
Builders sometimes forget why they are spending all this time in the work shop. The answer is on the wall over your left shoulder: "LIVE TO FLY' Put the tools down, get out of the work space and GOOOO FLYYYY. Once rejuvenated, pick up the tools again.
The fuel sender and the fuel tank need to be grounded to the airframe. I guess I can’t give a definite answer as to why, but perhaps because everything needs to be grounded for static purposes? Maybe someone can post a better answer?
That's essentially spot on. Adding bonding wires to Airframe components, especially fuel systems, is important for static mitigation. Having static discharge near fuel components has the possibility of being catastrophic, so if possible it's best to direct any stray voltage away This is the same for avionics and other ESD sensitive electronics
Mark I love your videos, very helpful. I'm currently building a CH 750 STOL I have an added tip for cutting holes in Fuel tanks that I tried when I did mine the other day. I took my shop vac and plugged in the exhaust side of Vacuum into the filler hole. wrapped some tape around it, turned it on and used a fly cutter to cut the 59 mm hole The inside pressure kept all the fillings out of the tank. Magic . Yes I rinsed the tank out to be sure it was free of debris. Cheers Andrew Atkins in Ontario Canada
Your attention to detail is legendary, Mark!! There are some excellent tips in this video, thank you.
Your attention to detail and taking the time to think through each step makes your CH750 SD build really fun to watch. One of my favorite channels.
Thank you! I appreciate the comment.
I'm loving this series, Thanks so for much for posting! I don't mind the "rambling" at all, in some ways it's the best part.
Burnout sneaks up on you and dishes out a really hard body check into the boards. (Canadian, eh) It happens in every profession I know. Thanks for reminding us all about how to deal with that. I'm truly enjoying this build. Keep up the great work.
ATD....Attention to detail. It’s what you do and it shows Mark. NICE! Keep up the great work. 👍
Enjoy watching your builds. Would like to encourage you as many of us would love to be facing burnout building our own aircraft.
This is an excellent video, not just on the sender install but touching on the burnout factor, a subject that get's overlooked when building, especially if you are doing everything all by yourself, sometimes it's just better to stop and walk away for a bit, before mistakes are made and needless money has to be spent twice. Keep up the fantastic job Mark.
You’re doing a great job👍🏻👍🏻🇬🇧🇬🇧
I just recently swapped-out my leaking VDO senders (9 years old) for the Stewart Warner senders. I had the exact same issue as you did - the SW senders seemed stiff and didn't move with small additions of fuel as I calibrated my senders. However, I found that I could rock the wings vigorously and the senders would settle on the new fuel level. A flexible "snake" video camera is helpful to peek inside and ensure the sender is floating on the fuel. Also, similar to your experience, I found it was a non-issue once I started flying again - the senders either loosened-up or the vibration helps them move - they now work great and are extremely accurate!
However, there are 2 critical differences between the VDO and SW senders! The VDO's plastic insulator for the center electrode deteriorates - mine were crumbling like chalk after only 9 years! I think sealing them in Proseal inside and out as you did might help, but who knows? I also suspect that mounting them on top of the tank as you did where the sender is not continuously bathed in fuel (vs the side of the tank mounting) will promote longevity. Secondly, the SW senders use a "thick film" resistor for long life/durability. This technology is used for approved senders for certified aircraft while the VDO sender appears to have a typical wire-wound resistor board that is mechanically rubbed by the sender's arm. A prominent EAB expert who writes for a major magazone told me he used those SW senders in his Van's RV and they were working great 25 years later!
BTW, Van's recommends just using Proseal for the SW senders and deleting the rubber gasket - apparently the Proseal alone is quite sufficient . However, I suspect the way you applied Proseal both to the tank hole's rim and the outside of the VDO sender and gasket will work great.
Another excellent video! Your attention to detail and explanations not only how to do things but why you did it the way you did are extremely helpful!
What’s great about this build site, is the detail you go into, which applies to other plane builds. Thanks!
Thanks Paul. I really wanted this channel to helpful to more than just Zenith builders. Hopefully people can learn a tidbit or two no matter which airplane they are building.
great advice buddy.
Love your videos. You may know this but didn't want to talk about it, but you can check the spec sheet for the seal to see the class and application time of the seal. When I taught sealing at the Boeing Company we covered this in excruciating detail. An example would be Class "B" with an application time of 1/2 hour. This means that it is a medium thick seal and you have 30 minutes from the time you mix it until the seal is applied to the surface. Another would be class "C" 20. Thicker seal but an application time of 20 hours. It looked like you used this: 3M™ AEROSPACE AC-350 CLASS B-1/2 - 25 GRAM KIT and you can see the time is 30 minutes.
I love your attention to detail. Great video!
@3:06 ... and a sledge hammer and a chainsaw and an ax... I'm like uh? but he said is so seriously that I had to go back 🤣 (the no showing the face part helps)
Thanks for the video. I didn't think I'd enjoy this as much as the Cruzer, but boy was I wrong. Keep up the good work!
Thanks for the tips⭐️⭐️⭐️⭐️⭐️👍🏻
Excellent tips!!!
I really enjoy your videos. They are very helpful as I build my SD. Did you shorten the arm of the sender? As I get ready to place mine in the tanks it seems shortening it by an inch or so would allow full travel.
How about adding some Blue Locktite thread sealant on the screw threads
No disposable surgical gloves when working with the pro seal? You’re braver than most builders. Great videos - thanks for all the time and effort that goes into making them.
It is proseal. the best to use for fuel in 1425 B2
I'm hoping that you could share the differences between a Zenith kit and a BushCar kit? They seem very similar?
I was curious as to why the p&s tubing doesn’t come straight to the rear spar? It still has to right angle irrespective of the exit point.
Did you do anything to clean out the inside of the tanks after drilling/cutting the holes for the fuel sending units?
"watch the rest of the video....." that will help
Curious if you intend to use something like ACF50 or CorrosionX as an ongoing maintenance item with the thought that primer may not last forever.
No.
Is there a torque spec called out for thesending unit screws? Nice clean job 👍🇺🇸
No. There are no instructions at all for the senders. This is where you have to use common sense. Don’t tighten them so much that you’re completely distorting the rubber gasket.
@@KitplaneEnthusiast Would lock tight be over kill?
In my opinion yes. First I’m not sure how the thread sealant would react to fuel. Secondly, I think the ProSeal around the screws will prevent them from turning loose.
Knock everything to the corner and vacuum out the tank.
Do not do this if you already have gas fumes.
So, Proseal on the mating surface between the rubber seal and the tank...got it
Do you put proseal on the mating surface between the rubber seal and the fuel sender ??
I didn't.
Awesome video again! My fuel senders (exactly the same as yours) came with 2 rubber seals per sender. Are those extra (or for a Volkswagen) or do some people put a rubber seal between the tank and the inside ring? Seems like that would be hard to do.
Hey Mark! I'm not quite visualizing how the ground wire is making a good connection to anything other than the sender mounting collar? Is that all that's required? After your experiences , i think I'll stick with the senders from Zenith. Thanks , Blue Skies!
Wait until the next video!
Another way would be to get a metal hole punch from GREENLEE or Chinese cheep one since you will only use it one time. You drill a small hole and just tighten a nut till the circle pops out of the sheet metal. The China ones from Ali Express are good for building a single plane.
How would you get the male punch part in the tank? I don’t see how that would work because to use those punches, you have to have access to both sides of the part you want to cut. They are great for punching holes in a firewall!
@@KitplaneEnthusiast The ones I had at work just like the fuel sender. There was a notch is the lower half to get it in and you get 75% of the hole then spin to get the rest. The ones at the place I worked were GreenLee.
Another thought would be to use a small router with a collet and a template out of plywood. Probably what I would do since I already have a router. Just wondering if there is a better way. Love the build!
Do you have a link to that tool? I’d like to see it. This sounds like a tool I’d like to buy!
@@KitplaneEnthusiast www.infinitytools.com/blog/2014/02/14/a-template-that-wont-put-a-hole-in-your-wallet/ A trim router would work well for this, you can also make your own and use a bit with a bearing on it to follow the pattern.
Builders sometimes forget why they are spending all this time in the work shop. The answer is on the wall over your left shoulder: "LIVE TO FLY' Put the tools down, get out of the work space and GOOOO FLYYYY. Once rejuvenated, pick up the tools again.
I flew the Cruzer twice today!
@@KitplaneEnthusiast With the beautiful weather in Michigan today, it was a great day to GOOOO FLYYYY!!!! High five!!!
@@KitplaneEnthusiast Mark Thank you for taking us along on your second flight of the day in the next video. The views were great.
Why don’t you pressure check the tanks rather than wet testing.
Looks like JB Weld
It does look like it, but it's not the same.
why ground wire?
The fuel sender and the fuel tank need to be grounded to the airframe. I guess I can’t give a definite answer as to why, but perhaps because everything needs to be grounded for static purposes? Maybe someone can post a better answer?
That's essentially spot on. Adding bonding wires to Airframe components, especially fuel systems, is important for static mitigation. Having static discharge near fuel components has the possibility of being catastrophic, so if possible it's best to direct any stray voltage away
This is the same for avionics and other ESD sensitive electronics
Stop procrastinating and GET TO WORK!
Still waiting on YOU to come over help flip the wing!