Roller Clutch Lubricator Drive

I'm thinking of making a 5" gauge loco. lubricator drive using 1/8" bore roller clutches, as suppliied by Arc, or is this not a good idea?

Can anyone tell me what sort of tolerance is needed on the 1/8" dia. shaft, also is the shaft an easy slide fit in the clutches to make assembly easy? I'll probably use hardened silver steel.

Thanks,

Clive

Nothing wrong with roller clutch drive lubricators, the tolerance required taken care of by using silver steel, hardened if possible.

You can buy hardened and ground dowel pins. Listed here at £15 for 25

**LINK**

no doubt someone sells them in one offs

Hi Clive, Duncan's suggestion of using a h&g dowel pin as the axle is a great one. A further suggestion when buying one way clutches is to make sure you know what firm made them, and that you have the model number. There is lots of info about the clutches and shaft sizes, finish, and hardness on most clutch manufacturer's sites, if you have the firm's ID and the model number you can look them up. One example is Koyo Jtekt's product manual at the link below.

https://koyo.jtekt.co.jp/en/assets/file/pdf/catb2024ex.pdf

Clive, I just did a couple of lubricators with 1/4" bore roller clutches, using hardened silver steel shafts. they work fine, but if the gaps between the rollers fill up with heavy steam oil, seems to be about 3 months use, the rollers cannot move, and the clutch stops working, easy to spot, and a few squirts of WD40 or equivalent and oscillating the lever a few times clears the oil and away they go again. I had a friend who made one with an 1/8" bore clutch and he had the same issue, but more often, no doubt because they are smaller. You will need a pair though, one to move the shaft forward, and another on the opposite side to stop it rotating back. Alternatively you could use a ratchet to stop it turning back.

Chris Gunn

Hi Clive,

There is some advantage to having a wheel on the end of the hardened shaft so you can turn it to prime the system and also give the cylinders a dope of oil before a steam up and run, though if your's is on a 5"g POW, then the oil will just collect on the steam chest cover.

The driving shaft must be hardened. By a few spare roller clutches. Carefully set the spring on the oil check valve to just above working pressure. This will reduce the system getting strained on a mechanical lubricator.

I prefer the Sight feed hydrostatic/displacement type for cylinder lubrication.

Cheers,

Julian