crash93

Have a look at this I posted some time ago on mayhem.


Fitting an oiler and ballrace

Attached Images

oiler1.JPG (74.1 KB, 9 views)

crash93

By the way I think the brass tube I used came from B & Q as the do 1 meter lenths of metric tube cheap.its a pity you only need 2cm.

peter

sunnybob

that looks good, but I'm desperately trying to keep the cost and work to a minimum on this model, and i think i would have to buy complete new shafts and tubes, as these are 50 years old, obviously well before metric was used in the UK, so nothing would match.

If i finish (no, WHEN i finish) the boat, if i find i enjoy the hobby, I might start "customising" it some, but for now, some light grease will have to do.
Bob

crash93

its even easyer use k7s brass and an imperial bearing,prob a lot cheaper
12" lenth of tube about £1 and the bearings are only at the most £1.50 ea so a cheap job if you have a way of mesuring the iner and outer I may even have some bearings you can have you only need to do one end of each. then use light oiil in the shaft and no loss of speed .

peter

sunnybob

crash, I've measured the bits and the shaft is 0.185".
The tube is 0.250" OD, and 0.190 ID.
The tubes are 14" long.

BUT, the shafts are built with soldered on supports which bolt to the underside of the boat, so they have to be installed by sliding them from outside, through holes in the hull that are only just big enough to take the tubes. If I add bearings to them, they would have to be detachable, and not increase the diameter of the shaft, otherwise they would not fit through the hull. Is that possible with the bearings you have?
Bob

crash93

you dont know the id of the tube itself do you ?


Peter

sunnybob

The tube is 0.250" OD, and 0.190 ID.

I missed out the " sign after the I.D. so thats 0.190" internal diameter,which according to my tables, is 4.826mm.

Bob

crash93

I am looking for some bearings now, I will let you know if I have any (I have a box full somewhere in the workshop) it should not take long , but in the meantime I would remove any grease and only use thin oil whith that little clearence between tube and shaft because the drag would destroy your motor at only 0.005" difference, thats very small its normaly about 3mm.

Peter

sunnybob

Peter, thanks for that, I'm very mechanical, working on mechanical and electrical stuff all day long, but the model world is a closed book to me. (I'm used to bearings that need a 3lb club hammer to remove, and half horse power motors)
Bob