Subject: Chain tensioner ideas
From: Old Nick
Date: 24/03/04 06:41 GMT Standard Time
Message-id:

Back to my post hole digger. I want to spring-tension the main drive
chain (5/8"). I was wondering if anyone has any useful ideas about
putting a chain tensioner together. Part of the reason is that I wll
have to use 2, because the chain fouls the mounting (my build :- ) if
I just tension one side.

I have thought of actually using a little sprocket, or a ball bearing
on a shaft (no drive needed, of course). But there was one picture
that appeared to simply use a piece of plastic! Presumably delrin, or
some other slippery, hard material? It looked quite narrow. I assume
it sits only on the chain rollers.

The chain is in exposed, dusty conditions, I might add. That was why
the dragging plastinc idea did not appeal.

Plastic tensioners are the standard method for cam chain drives in engines but
of course it's clean and well lubricated in there. Also such tensioners are
only used on the slack side of the chain. If you need to tension the drive side
of a chain the tensioner will have to withstand a fair amount of force. A
sprocket on a substantial bearing would seem to be the only way. Given that you
might as well make two.


Dave Baker - Puma Race Engines (www.pumaracing.co.uk)
I'm not at all sure why women like men. We're argumentative, childish,
unsociable and extremely unappealing naked. I'm quite grateful they do though.