Tree Mill Journeyman 300 retrofit

I am nearly done with the finals details on the Tree mill retrofit. The last
big problem that I ran into was there was more than normal noise coming from
the two speed gear and pulley driven spindle drive. So I took it apart and
was surprised to see fiberglas insulation packed around the inside of the
casting. There is a lube system that pumps oil to the countershaft pinon
gear and the spindle backgear. Of course the fiberglass was saturated with
oil. So I figured that it was added as a sound dampening. I removed it.
While cleaning the spindle gear case I also noticed two things. 1. there was
groove in the lower casting that looked like it was machined 2. there were
metal chips at the tangent of the pinion and bull gear. When I removed the
bull gear and cleaned it I found some significant pitting of some of the
pressure side of the teeth caused apparently by water entering into the
upper casting. This pitting was only on about 1/3 of the teeth. I checked
and found that there were no replacement gears to be had. I also noticed
that the back side of each tooth was fairly smooth. So I cleaned up the gear
and decided to mount it upside down since the gear was nearly symetical
from top to bottom thus I would have a new and better condition teeth in
contact with the pinion that was in great shape.
I ascertained that the groove in the bottom of the casting was caused by
the machine not being properly reassembled at some point in its history. I
noticed that the upper bearing retaining lock nut wasn't all the way on the
shaft threads. While I had it diassembled I lapped the threads in so I
could bottom the nut. When I reassembled the unit and test ran it I found it
to be a lot quieter. In the high speed position where the bull gear is
disengaged the only noise was normal motor noise. At 6600 RPM it really
sounds like there is small turbine running. In low speed at about 1800 the
gear noise is still there but drastically reduced.
I only plan to use the machine about 10 hours a week so I think I will pass
on having a new gear made.
The only things left to do is to do some more cleaning and painting. I plan
retain the existing electrial enclosures and after removing all the
electronics weld in shelves for tool holders, cutters and other supplies. I
think my $750 Ebay milling machine was worth the work put into it and I
enjoyed and looked forward to getting all the "rode hard and put away wet
problems" repaired and working like a good used but still with plenty of
life left in it.

Dan
Camtronics Inc
www.seanet.com/~dmauch