Roller chain tensioner ideas wanted

[Uncle Ernie]

Have any of you come up with a good simple way to build a chain tensioner? I need to make one for a project I am working on. #41 chain. Sprockets are about 6" center to center 1.5" and 2" diam. It needs to be the style that floats on the chain between the sprockets. Similar to a Pobco snapidle.
I'm too cheap to just go buy one (or two in this case)

 

[rabbit-1]

Have seen a number of roller chains tensioned by a rounded wood block rubbing, or running against a curved wood block. Could be tightened by a simple slot in the block, ans attached by a bolt to tighten the block in place.

 

[thurlow]

Have made many of 'em for old Gleaner combines out of whatever hardwood I had on hand.

 

[old]

I have seen 2 types of those. One as the other said are as simple as a piece of oak 2X4 set to push on the chain but if you want a more hi teck set up find a sprocket that has bearings in the center then mount that on an arm with a spring to pull it tight on the chain. JD use the sprocket set up on the 14T baler and IH used the wood block set up on one of there rakes and I have both machines so I have seen both set ups first hand

 

[Uncle Ernie]

I really need a floating type tensioner as this drive is reversable. The arm tensioners suffer badly when the load is reversed and the tensioner has to bear the load as well was tension the chain.
The use of hardwood is a good lead. Thanks.
keep any ideas coming!

 

[Frank A]

Roller skate wheel.

 

[PJH]

Wood block was the answer until you mentioned that it was reversable. Now you need to go to a sprocket tensioner. The wood will wear fast when you reverse it.

 

[NCWayne]

I've looked at one sitting on the counter in a supply house several times here lately. It's made with two bars side bars with thick pieces of self lubricating plastic bolted/attached between them. The two pieces of plastic have a slot cut down the middle to keep the chain centered in it, and have metal bars thru bolted on each side of them at the ends. Then there is a center hole where each is thru bolted to the two side plates sandwiching it all together. The two side plates have multiple holes so the floating pieces can be brought closer together or further apart to put the desired amount of tension on the center of the chain. Since the two pieces float/pivot instead of being held rigid they can withstand the chain running either direction like you need. This is basically the same thing I think the post below are talkign about doing with hardwood,, and this design could probably use wood blocks too, but the plastic will last alot longer if this thing is going to see alot of use.

 

[Morris Krodle]

Check with a motorcycle repair shop, they"ve been using them on cycle chains for years.

 

[Uncle Ernie]

Scrounged up a piece of UHMW plastic. Turned it into a 1 1/2" rod on the lathe, drilled a thru hole off center thru it and bolted it up to the frame next to the drive. I can rotate it to adjust the chain. Not as fancy as the floating ones I had envisioned but I think it will serve the purpose.

 

[GeneMO]

Osage orange (Hedge)

Gene