Clunk Line Length - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Engines Discuss engines

Thread Tools Display Modes
Old 11-09-2012, 03:45 PM   #1
Level 3 Supporter
★ Site Supporter ★
cravenjw's Avatar
I am: John C
Join Date: Oct 2011
Location: Ontario
Radio of choice:
Jeti DS-16
# of RCs: 8

Feedback: 36 / 100%
Posts: 1,221
Total Props: 18
Gas Clunk Line Length

       Remove this ad - become a site supporter!
I was on the fortitude gas tank website. They mentioned in the FAQs, their pre-installed clunk lines are short on purpose, because they would expand with exposure to gas. The lines are clear yellow (maybe tygon).
I am using viton tubing from thunderboltrc. Looking for advice on how long to make clunk line. Do you allow of line expansion with viton?
cravenjw is online now   Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 11-09-2012, 06:21 PM   #2
Lorne @
Authorized Vendor
★ Vendor ★
Lorne @'s Avatar
I am: Lorne L
Join Date: Jun 2008
Location: Alberta

Feedback: 7 / 100%
Posts: 1,846
Total Props: 11
Re: Clunk Line Length

I make the clunk line about 75% of the way back in the tank. This is so when I do longer down facing runs I don't stall. My edge with a JC-120 was stalling out every time I did a blender. I landed shortened the clunk to 75% of the way and it never happened again.

This is just my opinion and someone may be more of an expert on this.

I have always wondered if a fool proof header tank could be made for 3d planes that are headed strait down 20 % of the time?
Canadian distributor for EME Engines, 3DHOBBYSHOP, GP ENGINES, PRO-FLOW 3D CANS, TDRC 20 AWG Servo Wires,
Also: Savox Servos, Hacker motors, Castle Creations, Falcon Props, SWB MFG, Smart-fly, 4titude Tanks
Lorne @ is offline   Quick reply to this message.
Old 11-10-2012, 03:36 PM   #3
Dale Hunter
RCC Supreme Contributor
Dale Hunter's Avatar
I am: Dale Hunter
Join Date: Jan 2009
Location: Camrose, Alberta
Radio of choice:
a 12 X in each hand !

Feedback: 23 / 100%
Posts: 8,586
Total Props: 39
Re: Clunk Line Length

Like Lorne, I too leave a gap between the end of my clunk and the aft end of the tank. Depending on the physical size of the tank. For the sake of this thread, approx 1/2 inch short of the end.
While on this subject, I also do not use a second clunk in my 3 line tanks. But, simply use a length of fuel tubing long enough to get close to the back of the tank to remove the fuel at the end of the day. Time, and gravity will establish a natural curve to the bottom of the tank.
Hope this helps.
FishFly - FunFly, Sept 11-13. Great fun!
Trout Farm Flyers. Life is good.
Dale Hunter is offline   Quick reply to this message.
Old 12-11-2012, 11:10 PM   #4
RCC Supreme Contributor
I am: brodie h
Join Date: Apr 2011
Location: camrose ab
Radio of choice:
Graupner mz 24
# of RCs: 6

Feedback: 12 / 100%
Posts: 4,459
Total Props: 17
Re: Clunk Line Length

And don't forget hose barbs.
"Trout Farm Flyers"
North Star Laser And Vinyl Works
MAAC # 83720

bhughes is offline   Quick reply to this message.
Old 12-12-2012, 04:15 AM   #5
RCC Expert Contributor
I am: Brian Fisher
Join Date: Sep 2009
Location: North of Parry Sound, Ontario
Radio of choice:
# of RCs: 14

Feedback: 4 / 100%
Posts: 770
Total Props: 3
Re: Clunk Line Length

Viton does not expand in gas or smoke fuel.

From a guy who developed rubber compounds for 35 years.
Brian Fisher
Parry Sound Ontario
BAMDFISHER is offline   Quick reply to this message.
Old 12-15-2012, 10:18 AM   #6
RCC Pro Contributor
JimBrown's Avatar
I am: Jim Brown
Join Date: Mar 2003
Location: Rockland, Ont.
Radio of choice:
Jeti DS-16
# of RCs: 10

Feedback: 18 / 100%
Posts: 1,937
Total Props: 4
Re: Clunk Line Length

Originally Posted by fishfly View Post
I have always wondered if a fool proof header tank could be made for 3d planes that are headed strait down 20 % of the time?
Have a look at what the turbine jet guys are using. We really do not want an air bubble making its way to the engine as that pretty much guarantees a dead stick landing.

There are two styles:

The membrane style Hanson Supertrap or BVM Ultimate Air Trap

The center pickup style: Model Aviation Products Air Trap (Scroll down a bit...)

The center pickup air traps are also good to use on smoke systems. Helps stop that break in the smoke during down-line maneuvers.

Have fun!
JimBrown is offline   Quick reply to this message.

clunk , gas , tank , tubing , viton

Quick Reply

Register Now

In order to be able to post messages on the RCCanada - Canada Radio Controlled Hobby Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Member names may only be composed of alpha-numeric characters. (A-Z and 0-9)

!!ATTENTION ADVERTISERS!! If you intend on advertising anything on this forum, whatsoever, you are required to first contact us here . Additionally, we do NOT allow BUSINESS NAMES unless you are an Authorized Vendor. If you own a business, and want to do sales on this site via posting or private message, you will need to follow the rules. Shops, Stores, Distributors, Group Buys without being authorized will see your account terminated.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Your Name
Your first name and last initial is required if you plan on using the forum.
Which city & province you live in. This is mandatory for classified listings.
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
vBulletin Message

Thread Tools
Display Modes

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
felt clunk for gassers pura Engines 5 09-25-2012 12:04 PM
Lead out length. Flying line length kiwipaul Control Line and Free Flight 6 04-22-2011 04:45 AM
LRP Replaces the Neo One Line With The X-11 Vector Line MUSTGOFASTER Clubs, RC Tracks, Events & Bashing meets 8 02-01-2007 06:08 PM
fuel line length?? carkilla General RC Car & Truck discussion 6 01-30-2005 09:46 PM
The length is? ken park Fixed Wing 1 08-21-2003 04:05 PM

All times are GMT -5. The time now is 06:37 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.