Does Sequence of Polishing Operations Matter?

[Stan Pope]

I am interpreting the slightly greater intrusion of striations into the central white space from below to indicate that the surface variation is greater in Sample G. I don't know that for sure, but the geometry which (I think) is used by the photographic process suggests that it is true.

[Stan Pope]

It appears that neither sample shows effects of initial machining pass, so 30 micron was a reasonable starting grit.

I should ask Brady to photograph an axle which had been prepared up to just before the first (30 micron) polish was applied to serve as a basis for this conclusion. The prior steps included straightening, filing off the ridges, and machining the underside of the axle head to install a gentle taper.

[chromegsx]

I see the differences the same way you do. Although the difference is small its still visible via light reflection at edges of light source and in this case in the center of the light sources. Is sample H mis labled or did you actually skip 4 micron on your way to 2? Text and photo are not consistent. So was your sanding times consistent for all grits? Or did you try to vary the times in an attempt to compensate for what is shown in the photos as different.

[Stan Pope]

I see the differences the same way you do. Although the difference is small its still visible via light reflection at edges of light source and in this case in the center of the light sources. Is sample H mis labled or did you actually skip 4 micron on your way to 2? Text and photo are not consistent. So was your sanding times consistent for all grits? Or did you try to vary the times in an attempt to compensate for what is shown in the photos as different.

Good questions!

The jpeg has the typo. Had it been totally correct, I'd not have typed in the title! (Economy of activity, you know!) I "ran the plan", changing grit size by a factor of 2 (or 1/2) from stage to stage.

Process time for each grit was 15 to 25 seconds per, cleaning and stepping grits when the strip felt depleted. I was working with 1/3" X 4" strips in each grit and used most of each strip. In all cases, the wet abrasive paper/cloth was backed by 1/8" thick leather strip so that the leather applied pressure without having to have high tension on the paper. Speed was around 1500 RPM.

When the axles come back home, I'll run them on the "friction rig" to get its opinion. I did not want to run them before photographing because of reports that some powdered lubes scratch the axles. (Don't know if it is true or not, but that was the thinking.)

Not much more gonna happen here until I get the tax return under control. Still some reading and number plugging to be done. But now that the brokers have all their reports finalized, I can go ahead with more confidence.

[picard1963]

Stan, just checking in on this topic........hope all is well!

p63

[Stan Pope]

Yes, Bride is improving steadily but slowly. PT is, and will continue to be, painful for a few more weeks.

New batch of axles posted to Brady laying groundwork to correct defects in first batch.

[picard1963]

Godspeed to your Bride's recovery!