stunthanger.com
Building Tips and technical articles. => Building techniques => Topic started by: Chuck_Smith on March 06, 2021, 05:33:02 AM
-
Any experiences you'd like to share? Since I still struggle with fuel capacity on I'm considering conformal tanks.
I'm fine with fiberglass fabrication - done lots of it. My concern is that I know from experience that ethanol and fiberglass generally don't play nice together. Is methanol OK with epoxy? I still see people fuel-proofing with epoxy but that's not quite the same as soaking in it.
Chuck
-
Windy has done lots of videos on this. His we're mostly carbon fiber, but I see no reason that fiberglass wouldn't work. I do know he used Epon epoxy.
https://miller-stephenson.com/chemicals/epoxy-resins/epon-epoxy-resin/
Epon is some nasty stuff. Use ventilation and gloves, and keep in mind it will need post-cure treatment (oven) to reach full strength.
Biggest thing is a good mold. He made his in 3 parts, body and 2 end caps, with final assembly done with JB weld.
Hope this helps.
Steve
Sent from my SM-G970U using Tapatalk
-
Epon/teta will reach full strength without heat treatment if you want to wait 10 days.
Motorman 8)
Yes. (Straight out of the old Shell literature I have here.)
-
Pictures below show the stuff to use and a source. It's made for lining chemical tanks. Good old 815 gets soggy. Here's a good way to do it: https://www.nclra.org/TechTopics/WayneTrivin/CompositeTanks.html . Wayne Trivin and Jim Tichy used this stuff and died of cancer, so you might consider wearing nitrile gloves. I wouldn't use aluminum tubes with carbon, although maybe you could use the combination as a battery to start your engine.
-
Chuck,
If your query stems from your effort to get the endurance out of "Stuntzilla" I'd prefer to see you stick with tin soldering a metal tank and remain with us a little longer for another flying season. Sounds like some of these coatings will shorten your trip to the grave.
Steve
-
Pictures below show the stuff to use and a source. It's made for lining chemical tanks. Good old 815 gets soggy. Here's a good way to do it: https://www.nclra.org/TechTopics/WayneTrivin/CompositeTanks.html . Wayne Trivin and Jim Tichy used this stuff and died of cancer, so you might consider wearing nitrile gloves. I wouldn't use aluminum tubes with carbon, although maybe you could use the combination as a battery to start your engine.
As everyone knows, I am not a "safety screecher" but even I would draw the line with this stuff. I am not convinced that keeping it off your skin is sufficient. Given the negligible gain from a carbon or fiberglass fuel tank over nice safe solder, I would stick with conventional metal tanks.
Brett
-
whats the diff in making carbon tanks and making carbon PROPS ,should we outlaw carbon props H^^
-
whats the diff in making carbon tanks and making carbon PROPS ,should we outlaw carbon props H^^
You could have someone read you the above posts. I’m too lazy to look up the MSDS differences between the two sets of chemicals. I don’t remember the difference.
-
The other hobby I try to take part in as much as possible is vintage enduro type motorcycles. Bikes from the 60's and 70's frequently had fiberglass tanks to reduce weight to offset the weight of the 3 plus gallons of gasoline that enduro motorcycles typically carried on board. Fast forward to today, and the big problem with running original fuel tanks is the 10% alcohol in today's pump gas. Just this much alcohol can deteriorate the resin that the tanks were originally made up with. There are several products on the market that are designed to "line" the tank and protect it from today's fuel, but they have limited success. And that is just at 10% alcohol !! The only real solution is to run a plastic or metal tank and save the good original tanks for museum pieces, or to make sure you run only alcohol free gasoline in your bike. Even if you were to find sheet material for fiberglass and could assemble one, I think the fuel would get to the material after a short while. And from what I am reading here, using the special epoxy just isn't worth the few grams you might save. The weight can be collectively saved over the rest of the airframe and finish. i know Windy was working with carbon tanks but don't know what his results were or how long they lasted, but if anyone else is familiar with the results, I would be interested to know.
Type at you later,
Dan McEntee
-
i use the same resin for props and tanks
-
i use the same resin for props and tanks
You can do it if you take the necessary precautions, it's not plutonium. But I have great concern if you don't, this is not like mixing up Devcon from the HW store. It is particularly a bad idea for stunt plane fuel tanks, since you can make them so easily and it costs you piddling amounts of weight. I have one that Kaz made, it is beautiful, and I could have had Jim Tichy make all I wanted, but I can't see any reason to do it given the risk and the very minimal weight saving. Losing 1/2 ounce at the tank is 1/8 ounce off the tail, and I currently have 3/4 ounce of stick-on weights back there.
Brett
-
My carbon fiber pipes have limited lifespan, but an infight pipe failure isn't the same as an inflight tank failure. What got me thinking was Kaz's tanks but apparently he can't ship them to the US at present.
Chuck
-
Chuck,
Kaz can't send anything by air at the moment but can by sea. About 2 months wait.
At the height of the virus that is how long airmail was taking anyway!
Craig