rbent Forum - Fabrication of DuPont Delrin Chain Idler

bob wand

Ex Member

Re: Fabrication of DuPont Delrin Chain Idler
Reply #15 - Aug 24^th, 2018, 4:58pm

Quote from jayg on May 30^th, 2018, 8:25am:

Quote from Mdicke on May 28^th, 2018, 10:49pm:

Really nice job there Jay

Thanks, Mike.

After several hundred miles, the Harbor Freight O-ring has disappeared, and the chain is chewing on the idler. Need to try a higher quality O-ring. Not making near as much noise as a toothed idler, even without the O-ring. Will see how long the idler lasts.

Parker O-rings, Nitrile: (Buna-N) The most commonly used elastomer for O-rings because of its resistance to petroleum fluids, good physical properties and useful temperature range.
Back in the early nineties I tried a few and came to the conclusion that my chains were just plain hungry. T-cycle Idlers with a metal core work the best for me until somebody perfects a belt drive.

Back to top

IP Logged

jayg

Five Star Member

rbent member

Posts: 4127

Re: Fabrication of DuPont Delrin Chain Idler
Reply #16 - Aug 24^th, 2018, 5:46pm

Quote from bob wand on Aug 24^th, 2018, 4:58pm:

Quote from jayg on May 30^th, 2018, 8:25am:

Quote from Mdicke on May 28^th, 2018, 10:49pm:

Really nice job there Jay

Thanks, Mike.

After several hundred miles, the Harbor Freight O-ring has disappeared, and the chain is chewing on the idler. Need to try a higher quality O-ring. Not making near as much noise as a toothed idler, even without the O-ring. Will see how long the idler lasts.

Parker O-rings, Nitrile: (Buna-N) The most commonly used elastomer for O-rings because of its resistance to petroleum fluids, good physical properties and useful temperature range.
Back in the early nineties I tried a few and came to the conclusion that my chains were just plain hungry. T-cycle Idlers with a metal core work the best for me until somebody perfects a belt drive.

Some of the elastomeric O rings on my recumbents' idlers are resistant to the chain lubricants I use. Don't know what they are made of. I do know that Harbor Freight's "Nitrile" O rings are not resistant to the lubricants. Even though I have to replace the rings occasionally, I prefer idlers that use them to T-Cycle idlers, because they are much quieter.

Back to top

IP Logged

Action Lad

Five Star Member

rbent member

Posts: 1570

Re: Fabrication of DuPont Delrin Chain Idler
Reply #17 - Aug 28^th, 2018, 5:21pm

Quote from jayg on Aug 24^th, 2018, 3:05pm:

Quote from FlyingLaZBoy on Aug 23^rd, 2018, 9:00pm:

good work, Jay!

Thanks Paul. Just finished manufacturing and installing the idler on the left in the left photo. Replaces the broken idler on the right that I removed from Key L's Performer low racer.

http://i.imgur.com/XxoirOM.jpg http://i.imgur.com/oEVfFeo.jpg

And that drivetrain is shhhh! Whisper quiet! That cockpit is a peaceful place to focus on the work at hand.

Back to top

"You can't see paradise if you don't pedal!"
T.J. Fowler -- Chicken Run

IP Logged