[NSRCA-discussion] SODA BOTTLE FUEL TANK

[Wayne Galligan]

I sent a few photo's over the net last night if Michael filters them through of how I used the bottle cap.   I just used the rubber stopper on the back side of the bottle cap and just drilled two holes in the cap and one in the middle and screwed it in place like a normal stopper.  You can not over tighten the cap on these bottles.  They just wont strip out and they will seal just fine.  They way to test for leaks is to fill the tank full and then draw fuel out of the tank but close off the vent line creating a vacuum.  You will see tiny air bubbles if there is a leak.  So don't throw away those old fuel tank stoppers.  I use the 8oz and 12 oz bottles for smaller airplanes too.

Wayne Galligan

  ----- Original Message ----- 
  From: jivey61 at bellsouth.net 
  To: NSRCA Mailing List 
  Sent: Friday, February 17, 2006 7:29 AM
  Subject: Re: [NSRCA-discussion] SODA BOTTLE FUEL TANK


  Brian
   No don't use the bottle cap. I am using a old tettra tank cap. Cut off the bottle cap threads and push the tettra cap onto the lip.Then assemble as normal. 

  Jim Ivey
    ----- Original Message ----- 
    From: brian young 
    To: NSRCA Mailing List 
    Sent: Thursday, February 16, 2006 11:23 PM
    Subject: Re: [NSRCA-discussion] SODA BOTTLE FUEL TANK


    Sorry Im late into this thread but I gather the bottle cap is being used. And further I guess the threads arent shrinking so the seal is maintained?

    I might try and cook one up in a 215 oven immersed and filled w/ water.

    Rcmaster199 at aol.com wrote:
      Stress relief is a time-temp-chemistry sort of thing. Given the chance, PET will try to return to near it's original shape which was a thin walled, sealed at the far end, cylinder of plastic. If you weren't careful with the oven, you could potentially bring the thing all the way back. 

      What Jim is doing is a more controlled shrink down. Working with  the oven will work but takes more care.
        
       It may make some sense to fill the bottle halfway with water, make sure the cap has a hole drilled in it and then stick it in a pot of boiling water and cover but making sure the bottle doesn't tip over. You want the internal  pressure build up to be eliminated but you also want thread protection. Boil it for some time and then see how it shrinks. It will stress relieve and become stable quicker probably. Haven't done that myself but could be worth a try. GL

      Matt




      In a message dated 2/16/2006 9:54:37 PM Eastern Standard Time, brian_w_young at yahoo.com writes:
        Could you warm that material in an oven to acheive the same result?

        Maybe fill it w/ something to hold the shape but let it shrink.

        Rcmaster199 at aol.com wrote:
        Jimmy, pretty much all of those pop blow molded bottles are made of PET. A fine, very tough and resilient engineered plastic with terrific memory built in (beats heck out of my memory, fer shure). What you experienced is completely expected.

        Matt


        In a message dated 2/16/2006 5:16:58 PM Eastern Standard Time, jivey61 at bellsouth.net writes:
          Wayne
           I just flew the coke bo! ttle tank today and I get 15 minutes on 24 oz of fuel.It actually draws fuel down to 1 oz in the tank,doing the Masters pattern.
          The upside is I don't have to fill it full to complete the pattern. The weight savings is 2.5 oz using this tank.
           To review...... this was a 33 oz, 1 liter coke bottle' that I pickled with 30 % heli for 2 months.

          Jim Ivey

    _______________________________________________
    NSRCA-discussion mailing list
    NSRCA-discussion at lists.nsrca.org
    http://lists.nsrca.org/mailman/listinfo/nsrca-discussion 




----------------------------------------------------------------------------
    Relax. Yahoo! Mail virus scanning helps detect nasty viruses! 


----------------------------------------------------------------------------


    _______________________________________________
    NSRCA-discussion mailing list
    NSRCA-discussion at lists.nsrca.org
    http://lists.nsrca.org/mailman/listinfo/nsrca-discussion


------------------------------------------------------------------------------


  _______________________________________________
  NSRCA-discussion mailing list
  NSRCA-discussion at lists.nsrca.org
  http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20060217/46cb4008/attachment.html