Rant......Pre assembled fuel tanks.

[ericb]

I kinda feel like stangflyer. But those using the new type tanks will have deaf ears hearing about Dubro tanks. Things always change and if you are in the change age group you use the newest ideas and equipment. You all worry about leaks though and I found I never had a leak with a Dubro thank and Sullivan aluminum cap. I suspect other brands of aluminum caps are good but Sullivan was the first. I found you had to sandpaper the cap a bit to fit the Dubro tank. Always used the Dubro stopper. I saw many leaking tanks and they were always the tanks that came with kits. I hated putting a tank together but soon found I enjoyed the challenge and loved it when I dunked it in a water bucket and found no leaks. Those clear plastic bottles look a bit delicate to me. Gas engines rattle the heck out of everything. Try to tear up a Dubro tank. They are tough.

Have you ever tried to burst or wreck a water bottle? (not the new eco friendly thin walled ones) They are tough as nails.

 

[Husker]

Drop a full dubro from about 10 feet up on to concrete and it will likely split at the seam. Drop a full water bottle and it will dang near bounce back up to your hand...with no leaks.

Not that they need to hold up to that kind of abuse but the bottles are considerably stronger.

Also, Sullivan caps use stoppers.

 

[Terryscustom]

Drop a full dubro from about 10 feet up on to concrete and it will likely split at the seam. Drop a full water bottle and it will dang near bounce back up to your hand...with no leaks.
Not that they need to hold up to that kind of abuse but the bottles are considerably stronger.
Also, Sullivan caps use stoppers.

For me its not just a new thing to do but actually a big weight savings. Light planes fly better.

Absolutely! I switched to water bottle tanks for two reasons.
- One, I was using the Sullivan cap system on my dubro tanks and got fuel in three planes (I was a noob so may have been partially my fault). Supposedly they changed their stoppers finally, but I'm not going to test that.

- Two, as I started to fly more 3D and post stall stuff It's an easy way to shed off about half the weight of your fuel system. The water bottle and PETG bottles are nearly indestructible as far as our use is concerned. Its the caps and fittings that are the alkalies heal of them. That's except for PSP fittings.

 

[Ohio AV8TOR]

For me its not just a new thing to do but actually a big weight savings. Light planes fly better.

I am having small issues with your comment "big weight savings". Is there a weigh saving, yes I am sure but Big, I don't think so. I am finishing up a 91" EF Extra and in doing a lot of reading I see people using 24 oz tanks and 32 oz tank for the most part. I also read how much fuel is left in those 32 oz tanks after they land. That extra fuel weight is considerably more than that small tank weight difference especially on takeoff. I see people using ignition mounts, really? That is heavier than a cable tie and a small piece of Velcro. Batteries are another, why do you need capacity for more than 8 flights ? Now I am not debating the merit or weakness of each of these just as you should not say "Big weight Savings" for the use of a water bottle tank over a Dubro tank.

 

[Terryscustom]

Now I am not debating the merit or weakness of each of these just as you should not say "Big weight Savings" for the use of a water bottle tank over a Dubro tank.

Gasoline weighs .77oz. per fl. oz. If you have too much left you don't have the right size tank. It is a necessary part of the flight so weight on take-off is irrelevant in a proper sized tank. On my 70cc planes I land with roughly 4-5oz. after my timer goes off. A water bottle tank in the 32oz to 50oz size vs. a dubro tank is about a 60% weight savings so absolutely yes the savings is huge.

Sorry but the rest of your list is purely user preference, some of them I completely shake my head at as well.

 

[Hoosier06]

Absolutely! I switched to water bottle tanks for two reasons.
- One, I was using the Sullivan cap system on my dubro tanks and got fuel in three planes (I was a noob so may have been partially my fault). Supposedly they changed their stoppers finally, but I'm not going to test that.

- Two, as I started to fly more 3D and post stall stuff It's an easy way to shed off about half the weight of your fuel system. The water bottle and PETG bottles are nearly indestructible as far as our use is concerned. Its the caps and fittings that are the alkalies heal of them. That's except for PSP fittings.

We learned very quickly that the stoppers that came with the Sullivan aluminum cap set up were junk. That is why we used Dubro gas stoppers, brown in color. I made contact with Sullivan then years ago and he could not agree that his stoppers labeled for gas were disintegrating.
I won't argue about ounce weight savings for a tank or dropping one from a three story building or whatever.

 

[Ohio AV8TOR]

Terry are those both 32 oz tanks? You should pull the extra two Tygon lines off the Dubro to be fair though. But I have never implied they would be equal and am not making that argument. I fly 24 oz tanks as I do not merit the extra flight time of the 32 oz. That's 8 oz of savings for me.

 

[The_Wreck]

Ounces are ounces. You care about enough ounces you get a pound or two. Of course I shelled out the bucks for a magnesium da200, so my perspective may be a little warped....That cost me $650 bucks for 8 ounces over the lightened 200. So for me saving 5 ounces for the price of PSP cap is a no brainer.

Ohio just put 8 ounces less gas in the water bottle, nobody says you have to fill them up.

 

[Ohio AV8TOR]

Ounces are ounces. You care about enough ounces you get a pound or two.

Exactly and that was my point the added weight of batteries, fuel capacities for super long flights and weight from bling. I have never used a Dubro tank in a gas plane. I am giving it a thought for the first time because I cannot find a square 24 oz tank. Before you say use a 32 oz tank and fill it less I just may and already have it made.

 

[Terryscustom]

Wreck has a point, I've seen people put a small section of tygon inside the vent fitting to keep the fill level down. Other option is a smart water 24oz and just build a balsa cradle, would not weigh much of anything.

I'm confused, sounded like you were arguing that using water bottles was not worth it and the savings was not much......but then you say you've never used a Dubro tank?