Router Turned Grinder - Question(s)

Both youtube and photobucket are blocked at work. I used my phone to watch the video, but no luck with the photos so the thread was hard to follow, as it just said, "in the third photo...". I see now that there is more textual explanation further down.
 
The photos are clearer than the video. In the photos the rig is running on the tops of the vees, which should not be worn. On the other hand, there is no reason to expect that they ever would have been scraped in or precision-ground either since they are not reference surfaces. The X axis seemes to be controlled by rollers on the front and back vertical faces. Wouldn't these also be worn?

I still don't like the grinder trailing out behind. Every time the front roller hits a bump it is going to make a divot. If it was midway between the rollers it would average the positions of the rollers and so improve flatness with repeated passes, at least over the span of the rollers.

Maybe use the tailstock ways to grind the carriage ways? The tailstock ways won't be worn much in the area where the carriage ways wear most.
 
While I have not yet checked out all the photos, nor yet read through all the Practical Machinist thread, there are enough showing a dial indicator being used, and an impression of a very serious effort and skill in all. I do not have enough experience to seriously challenge work like this. Even so, for now, I do not abandon my first opinion that the surface was not being treated well.

Simple stuff like pausing, dwelling, and simply changing direction for a new pass that was seriously cutting, confuses me.
Was the arrangement maybe a bit flexible?

On my (first) lathe, there is some unworn way at each end where the original oil retention surface markings (frosting?) is intact.
I suppose a long girder-type parallel straight edge fixed across between the "good" bits would provide a reasonable reference to some sliding carrier for a grinder. Even after that, the surfaces would probably have to be tested/scraped to simultaneously bring them onto alignment with the spindle axis, and each other, as well as ending up flat.

Second best might be to get one bed way right, then use it as the track to grind the next.

I cannot dismiss the time, expense and skill implied, certainly before I have read and understood all of it.
It is just that some fundamentals seem to have been skipped. Maybe it is just the way I am.

I don't like thinking of myself as an "armchair critic", and I hope I was not directly "bashing", but I can't yet shake my first thought that the lathe was being made worse. Either that, or I am slower than my usual slow(ish) in getting to understand something.
 
intjonmiller said:
Thanks for the insights, Andre.

I'm confused about it as it seems to be referencing the very ways that are not in good shape in order to improve them. No?
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Yes yes! Sorry Jon. I missed that you made the point before me.

Somewhere, I have heard of "planing the ways" as opposed to grinding, but if the planing kit in any way uses the old worn ways to hang on to and determine the cut surface, then that too, does not work for me.
 
graham-xrf said:
Yes yes! Sorry Jon. I missed that you made the point before me.

Somewhere, I have heard of "planing the ways" as opposed to grinding, but if the planing kit in any way uses the old worn ways to hang on to and determine the cut surface, then that too, does not work for me.
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Since he's running on the tops of the ways rather than on the worn surfaces as I first thought I suppose this process mighr improve very badly worn ways.
 
graham-xrf said:
Yes yes! Sorry Jon. I missed that you made the point before me.

Somewhere, I have heard of "planing the ways" as opposed to grinding, but if the planing kit in any way uses the old worn ways to hang on to and determine the cut surface, then that too, does not work for me.
Click to expand...

Planing ways is done before scraping as a way to remove the bulk of material down to the low spots. It is done on a massive machine called a planer. Way grinding is usually done on a equally huge surface or way grinding machine. Look up "Mattison surface grinder" to get an idea of the size of machines that would grind ways.

What Ken did is somewhat unusual, but not unheard of. I have a PDF file of an article called "RENOVATING A LATHE BED by F. J. LANGFIELD" that shows a very similar method to what he did. This is not the way it's done commercially in most cases, but it worked fine.
 
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