Since finishing my 10EE in between making stuff I have been working to reduce the noise. The first thing I did was replace the big bearings in the reduction gearbox. I detailed this work in a previous thread, and while there was a slight reduction in the gearbox noise, it was less than I had hoped for.
Next I replaced the 4 sliders in the gearbox. Mine were worn, I knew it and ignored it, but I had to quit ignoring it. $40 each from Monarch. Best purchase I have made from them. The new sliders made a huge difference. Less rattle while running, and even more noticeable, my Parker 514 can stop the spindle in about a second, but before there would be a claptrap of noise when stopping. Now it stops with essentially no noise.
Noise that I thought was coming from from the tach turned out to be the phenolic gears in the headstock. Can't do anything about that.
Along the way I borrowed Everettengineer's pulleys and was able to true my two pulleys. My lathe had been run with one belt for obviously many years and I had uneven wear between the two grooves, as well as uneven wear from one side to the other in each groove, on both pulleys. After truing the pulleys I was able to use two belts instead of one, which reduced the noise further. My theory on this is that with one belt, there is a very slight torsional vibration. As the belt hops around the effective diameter of the pulleys change, which changes the RPM, which is the same as a rotational acceleration/deceleration, which causes vibrations. Vibrations are noise. With two belts the hopping around of one belt is cancelled by the hopping around of the other belt which reduces the vibration and noise.
Next I trued the zinc idler pulleys. The wear grooves were different on both pulleys, so now with two belts both belts were not running on the same diameter which meant one or both had to slip. Slipping is noise. With the pulleys trued the noise decreased further. Dealing with the pulleys brought to light the bolt issue I asked about in a previous thread, and as a result I loctited the bearings onto the bushings on both pulleys. Further reduction in noise as there is no possible movement of the bearings on the bushings.
With the drive pulleys and idlers true it became apparent how inconsistent "identical" belts are in length. Browning offers a machine matching service to get belts as close as possible to the same length. Expensive, but now obviously worth it. With the matched belts the tension is even between the two belts so I was able to adjust the tension properly. There is less noise as the hopping around of the two belts is much more even than with the previous "identical" length belts and I don't have to compromise tension, with one belt too loose or the other belt too tight.
https://www.regalbeloit.com/-/media...Commercial-HVAC/Belt-Drive-Monthly-Vol-23.pdf
So now with all this accomplished the predominant noise is the whirring of the phenolic gears in the headstock, even up to 4000 RPM, pretty impressive.
Off-topic now. Cal showed his zirc fitting caps for the leadscrew and feed shaft bearings. I made removeable plugs out of delrin and used an o-ring to seal the fit. The two upper plugs have an extension to grip with pliers to remove, the ELSR rod plug doesn't need to be pulled out since the rod can be used to knock it out.
Next I replaced the 4 sliders in the gearbox. Mine were worn, I knew it and ignored it, but I had to quit ignoring it. $40 each from Monarch. Best purchase I have made from them. The new sliders made a huge difference. Less rattle while running, and even more noticeable, my Parker 514 can stop the spindle in about a second, but before there would be a claptrap of noise when stopping. Now it stops with essentially no noise.
Noise that I thought was coming from from the tach turned out to be the phenolic gears in the headstock. Can't do anything about that.
Along the way I borrowed Everettengineer's pulleys and was able to true my two pulleys. My lathe had been run with one belt for obviously many years and I had uneven wear between the two grooves, as well as uneven wear from one side to the other in each groove, on both pulleys. After truing the pulleys I was able to use two belts instead of one, which reduced the noise further. My theory on this is that with one belt, there is a very slight torsional vibration. As the belt hops around the effective diameter of the pulleys change, which changes the RPM, which is the same as a rotational acceleration/deceleration, which causes vibrations. Vibrations are noise. With two belts the hopping around of one belt is cancelled by the hopping around of the other belt which reduces the vibration and noise.
Next I trued the zinc idler pulleys. The wear grooves were different on both pulleys, so now with two belts both belts were not running on the same diameter which meant one or both had to slip. Slipping is noise. With the pulleys trued the noise decreased further. Dealing with the pulleys brought to light the bolt issue I asked about in a previous thread, and as a result I loctited the bearings onto the bushings on both pulleys. Further reduction in noise as there is no possible movement of the bearings on the bushings.
With the drive pulleys and idlers true it became apparent how inconsistent "identical" belts are in length. Browning offers a machine matching service to get belts as close as possible to the same length. Expensive, but now obviously worth it. With the matched belts the tension is even between the two belts so I was able to adjust the tension properly. There is less noise as the hopping around of the two belts is much more even than with the previous "identical" length belts and I don't have to compromise tension, with one belt too loose or the other belt too tight.
https://www.regalbeloit.com/-/media...Commercial-HVAC/Belt-Drive-Monthly-Vol-23.pdf
So now with all this accomplished the predominant noise is the whirring of the phenolic gears in the headstock, even up to 4000 RPM, pretty impressive.
Off-topic now. Cal showed his zirc fitting caps for the leadscrew and feed shaft bearings. I made removeable plugs out of delrin and used an o-ring to seal the fit. The two upper plugs have an extension to grip with pliers to remove, the ELSR rod plug doesn't need to be pulled out since the rod can be used to knock it out.