12-24-2014, 08:12 AM
Some pics of the difference in the bearing thickness, recessing the gear to offset the difference, and the tool I built to install the bearing and the elevation screw as one assembly.
New bearing (top) and old bearing (bottom).
Here you can see the difference in terms of the shaft length. The bearing carrier should be flush with the top of the bearing.
I could have turned down the corresponding amount of thread from the actual screw but there is a locating pin for the carrier that I would have to move as well and it wasn't worth the hassle. Recessing the gear was a much simpler solution.
As usual, my 'special tools' are cobbled together from scrap bits laying about. It was a bit of a challenge to find enough bits to incorporate the length of pipe with the outer diameter to ensure the outer race of the bearing is being driven into the casting. Not pretty but it worked a charm
Now that big heavy chunk of cast iron is back on the column and it is starting to look more like a mill.
I've still got to make a tin hat to cover the gears.
The most difficult part was plumbing the oiler. The copper going from the oiler into the knee and the plastic line from the knee junction to the elevation nut were trashed. Finding compression fittings for this size pipe has been difficult but I managed to find a coupler, which enabled me to connect the broken plastic line to the inlet of the junction in the knee.
As I had to put a new oiler on, I managed to do away with the need for a junction on the side of the knee (oiler to junction, junction to knee and saddle). I didn't have any of the armoured sleeving to cover the re-purposed plastic tubing, so I used a spring. I'm pleased with the result.
I still have to fix up the line to the elevation nut, as the olive that fits the plastic line is too small for the metered oiler (it is an automotive oil gauge line). Once that is done, I can pressure check the system and ensure that the metered oilers are not blocked.
New bearing (top) and old bearing (bottom).
Here you can see the difference in terms of the shaft length. The bearing carrier should be flush with the top of the bearing.
I could have turned down the corresponding amount of thread from the actual screw but there is a locating pin for the carrier that I would have to move as well and it wasn't worth the hassle. Recessing the gear was a much simpler solution.
As usual, my 'special tools' are cobbled together from scrap bits laying about. It was a bit of a challenge to find enough bits to incorporate the length of pipe with the outer diameter to ensure the outer race of the bearing is being driven into the casting. Not pretty but it worked a charm
Now that big heavy chunk of cast iron is back on the column and it is starting to look more like a mill.
I've still got to make a tin hat to cover the gears.
The most difficult part was plumbing the oiler. The copper going from the oiler into the knee and the plastic line from the knee junction to the elevation nut were trashed. Finding compression fittings for this size pipe has been difficult but I managed to find a coupler, which enabled me to connect the broken plastic line to the inlet of the junction in the knee.
As I had to put a new oiler on, I managed to do away with the need for a junction on the side of the knee (oiler to junction, junction to knee and saddle). I didn't have any of the armoured sleeving to cover the re-purposed plastic tubing, so I used a spring. I'm pleased with the result.
I still have to fix up the line to the elevation nut, as the olive that fits the plastic line is too small for the metered oiler (it is an automotive oil gauge line). Once that is done, I can pressure check the system and ensure that the metered oilers are not blocked.
Hunting American dentists since 2015.