Hello from Oxford – Problems with a SABEL lathe

[Brian WoodParticipant @brianwood45127]

Hello Stephen,

I think I have found them, they must be the small holes at the bottom of the wedge shaped outer annular steps machined into the bearing housings which I thought were intended to work much like labyrinth seals and drain oil back into the well below the bearings.

Pulling pins out of those while manipulating the spindle, pulley cluster, thrust bearing and vee belt into position and avoiding disturbing the spindle during pin extraction requires careful choreography of a cast of thousands to do it all, not forgetting the dolly bird to mop sweaty brows and murmur nice things to mitigate the language.

Perhaps K has found out how all that is done on his own without losing your temper. I look forward to seeing what he says.

Regards

Brian

[inapickleParticipant @inapickle]

Hey guys

On my lathe there were no pins at all and I thought they were for oil recirculation- i.e when the oil gets out from the bearings it ends up in this wedge and then goes back to to the wick through these holes..
Maybe thats the reason Im having oil leak at the front of the spindle?
As for fitting it all in I watched a few vids on youtube how its done on southbend 9a or logan lathe, theyre both very similar machines to this one

Anyway bearing blue arrived. How do I go about testing it? Light smear on spindle and put in in? Rotate or not? Leave the bearing cap bolts loose?

Heres some pics, might be false reading, I just smeared it over as even as I could, put it in, turned it couple of times with the bolts fully loose. You can also clearly see where these holes are. Theres 2 of them per bearing

https://ibb.co/album/hpMmiv

[Brian WoodParticipant @brianwood45127]

Hello K and Stephen,

I didn't say pins were a standard feature, just that those holes must have been the ones you used to hold down the felts against their springs when you re-assembled the spindle. The pictures are a bit hard to interpret to offer definitive opinions on, blue seems to be present over the whole surface of the bearings and with slack bolts I don't think that is a bad state of affairs.

Did you try lifting the spindle and moving it sideways to feel for any detectable slop, that would be a rather more definitive test in my opinion.

Out of interest I checked my spare spindle in the spare headstock today with just an oil film on the spindle, there was no detectable slack on either bearing with slack bolts and maybe a very slight degree of added drag with the bearing cap bolts pulled down hard on the shim stacks–it still rotated easily. Those threads by the way are 3/8 inch WHIT16 tpi.

UNC bolts are also 16 tpi but they will have the sharper 60 degree thread pitch which will not give the best fit in the headstock since the mismatch in thread angles will only allow partial contact to be made in the thread walls and the thread tips are finished differently. The UNC bolts may even be contacting the bottom of the WHIT form tappings. Try the situation with known cap bolts instead to see how things behave then; I think you will get a much more gradual degree of adjustment as a result.

The headstock fitted on my working lathe has oil cups on the top of the bearings, as well as the sprung felts and the little push fit plugs to the top up holes alongside the oil wells. One other difference is the inclusion of a grub screw in the upper side of the bearing cap to get a grip on the bearing adjustment bolts and lock them at a chosen setting. I didn't like the way they were compressing the thread on the cap bolts at those points and machined them away to allow the grub screw to grip on a plain diameter of the bolt instead

Finally, the strange bronze collar thing will definitely prevent the chuck and spindle registers from meeting as they should to properly align the chuck in its fully seated position; at the moment it is only located by the 8 tpi spindle thread and will be inaccurate to a variable degree as a result, You can't expect the lathe to do anything accurate like that so take it off, it is doing you no favours.

Regards

Brian

[donald tibbettsParticipant @donaldtibbetts96401]

Hey all,

Long time reader, first time poster.
Also have a Sabel picked up recently (Also around Oxford too)
Regarding the headstock bearing lubrication, i find that if i squirt a bit of oil into the holes under the caps, generally the level always drops to the same level in a few seconds, and leaks out of the overflow and down the front below the spindle. Was wondering if others see this behaviour, or if I may be missing a felt wick or something. The oil I've been using is pretty thin stuff supposedly for plain spindle bearings on machine tools, so hopefully not far off correct.

Thanks

Don

[Author]

Posts