Re: Six Inch Lathe (ways)
- Mine had two problems:
1. wear near the headstock, resulted in either sloppiness in that
area, or binding when the carriage was more than a couple of inches
2. Bowing BOTH front/back and vertically, by as much as 7-8 thou.
Similar problems on the cross slide. I suspect the castings were
very "young" when machined, finding their natural, post-stress form
as the months and years passed.
So, unless you have a very good straightedge and lots of patience,
scraping may become a medium-duration career.
I was lucky in that a friend let me use his big mill, and flycutters
did a very nice job. I suppose I could do some lapping, but it "feels"
very smooth both to the touch and when using the handwheels.
Important to remember - the bed IS flexible, so anchor it to the table
of the mill or grinder in pretty much the same way as it will be bolted
to its normal bench. Believe it or not, you can distort it a few thou
Also, taking too much off the top surface of the "near" way can result
in the drive pinion and rack not engaging properly. Moglice or
similar to build up the undersurface of the carriage may be the best
way to attack this, but only if there is a real problem.
I also had to fiddle with shims and the dimensions of the gib on the
rear of the carriage, to get it nice and snug. This made a huge
difference in vibration levels.
Get everything nice and clean - grit free before reassembling, so
that you don't do some unwanted lapping without knowing it.
As a test, I rigged up my milling vise - into the normal toolpost
T-slot on the compound - and while it isn't the most rigid setup
in the world, it is at least usable, which it wasn't before the
tune-up. It's a small Palmgren, and I might be persuaded to
part with it....