Clunk Line

[jaguar bone]

Thanks Lee for the Viton heads up - this has been educational.
Thanks for doing the testing. Did you ever soak the test samples in petrol for a while and then retest pliability?

[STLAV8R]

Who sells the Viton other than McMaster?

[RCAddiction]

I have not done a soak test on Viton in many years. I believe that there may be some fluids which can cause it to harden but not gasoline or alcohols. Typically it will swell volumetrically by a few percent and may get slightly softer.

There are many other sources for 60 durometer 1/4" Viton/fluorocarbon tubing but most are industrial and require high volume purchases.

[jaguar bone]

So those interested, what length would you think acceptable to purchase ? I'm thinking 2' lengths is reasonable set unit. That's about 3 tanks
I'm hunting for a wholesale source guys. This looks like a really smart product mainly because I personally HATE maintenance - anymore.
Use to be fun to fiddle with all that stuff- now its just a must do.

[Stripe]

	Quote: Originally Posted by RCAddiction
	Okay, I've done some "flex deflection" testing. Precisely measured 4" lengths of new samples of the fuel tubing were fed thru a 1/4 ply plate. 4" seemed like a reasonable length for a moderate sized fuel tank. The plate is thick enough and holes fit tight enough so that the tubing did not flop around in each hole 4 identical fuel clunks (same weight, brand, etc) were applied to the end of each piece of new tubing. The Aerotrend had a bit of a curve to it which I oriented laterally, to minimize any effect on the direction of the deflection test. The Tygon had a smaller curve to it. Except for the 3/16" Hayes, the other tubing is nominally 1/4" OD. Photos: Tubing hanging vertically with clunk at bottom, left to right. Tubing hanging vertically with clunk at bottom, front to back. Tubing plate rotated counterclockwise to observe amount of deflection of each tubing with the same weight on it Tubing plate rotated back clockwise to observe the amount of deflection in the opposition direction Tubing returned to vertical hanging position once more to ensure nothing had moved significantly. Left to right and front to back - the Hayes is the thin black tubing. The Viton 60 durometer is the thick black tubing, then the Blue EasyFlex, then the yellow genuine Tygon. Results Within the realm of our use, the Tygon, EasyFlex, and Viton are very close to identical when brand new. The EasyFlex ultimately had slightly more deflection but it was not immediate. The Viton reacted more quickly to a change in direction than the other 2. If I had 3 hands, I would have taken a video to display this. The Hayes is significantly more flexible. It has the advantage of being smaller in diameter, with thinner walls, and is a softer material.

Lee

This might be old news now but I playing catch up thanks for the lead on the viton just got my order in from McMaster and I finally figured out why my engine would bog down in the KE not only was the line stiff but it was stiff and favoring the right side of the tank, dead stick city. Thanks and keep up the good work.

Stripe

[rcign]

I buy and use Hayes...I have lots...Send me your address, I can send you 5 or 6 feet..Free, for testing..I want to silence all the naysayers...Or not....

fwiw, it's about $.50 a foot in 100 foot lengths..

[js/rc]

	Quote: Originally Posted by Stripe
	Lee This might be old news now but I playing catch up thanks for the lead on the viton just got my order in from McMaster and I finally figured out why my engine would bog down in the KE not only was the line stiff but it was stiff and favoring the right side of the tank, dead stick city. Thanks and keep up the good work. Stripe

I don't think you can go wrong with Viton inside the tank & be sure & have the barbs on the brass tube !! We know here from experience !! The line came off inside the tank of my son's Yak, causeing big all winter long repairs !!
Thanks, John

[TooBizzy]

I've used Hayes for the past few years and have not seen any issues talked about here. Maybe the type of fuel your using? Additives? To address the tubing coming off the clunk, I cut about a 1/4" piece of the tubing and double it at the connections inside the tank. Never had the tubing come off or crack inside the tank using this method.

Maybe Viton is better??? I would have to experience a failure with what I'm using to look for something better. So far that has not been necessary....

[rcign]

My experience exactly...
Real Hayes comes from Custom Injection Molding in California...Maybe some of the tubing sold as Hayes comes from elsewhere...

[Stripe]

Ralph and 2Biz

I've never tried the stuff from Hayes the price is certainly right, how long does it last before it stiffens up?

[TooBizzy]

So far I've used it for over 2 years in a Gasser Heli and over a year in my 50cc Yak. Also use it in my 20cc Extra....I've never replaced the lines and they are as flexible as the day they were installed. I do drain my tanks after each outing....I'm not seeing any of the issues posted. I buy mine from TH....

[bobrev06x]

this is the stuff right here. http://www3.towerhobbies.com/cgi-bin...&I=LXK824&P=ML nice and flexible. once it's put on the brass tubing through the stopper, it doesnt slide off. i tie wrap mine anyway .... because i can. i also overlay another short piece over the clunk connection. never a problem.

[js/rc]

The thread originaly started out about Tygon hardening up, which is what every person in our area clubs has been using for many years. None of us here ever used Hayes but we all have had the Tygon harden up inside our tanks & we're all putting the Viton in our tanks now which is not supposed to harden up in there !! If the Hayes doesn't harden up, & remember we live in the snow, & it doesn't break down & go in your carb, then it's probably ok for you. I just know I use Viton in the tanks now & Tygon elsewhere !!
Thanks, John

[TooBizzy]

I might add I run Hayes from Clunk to Carb....@ $5.50 for 4 feet, the price is right. I'd have to experience failure before I would consider $4 bucks a foot for Viton....Looks like the choice is Hayes or Viton....Pick your poison!

[bobrev06x]

definitely hayes for the clunk line. just make sure the ends of your tubing are not sharp. piece of cake and trouble free.