Talk:Lapping

Please let us know the details of lapping machine Speedfalm we want to bye the same for the lapping of diamond tools.

The company's web site is here: [1] You might also want to take a look at Lapmaster [2]--gargoyle888 07:52, 30 October 2005 (UTC)[reply]

Two-sided lapping?

Wow, who dropped this bit of personal opinion and DIY instructions in the middle of a seemingly coherent article? 18.238.7.12 (talk) 07:33, 22 July 2008 (UTC)[reply]

Sanding

What is the difference between sanding vs lapping. Is it merely a difference between fields (wood working vs metal working) or is there some mechanical difference. The article should refelct either the similarities or the differences between sanding and lapping. —Preceding unsigned comment added by 216.136.104.21 (talk) 22:06, 5 May 2010 (UTC)[reply]

I don't know where you get the idea that lapping and sanding are similar, seeing how lapping doesn't use sandpaper at all and is done to materials much harder than wood. Please read the introduction of this article for a good overview. Wizard191 (talk) 22:55, 5 May 2010 (UTC)[reply]

flatness vs roughness

"Surface roughness and surface flatness are two quite different concepts. Unfortunately, they are concepts that are often confused by the novice."

Please explain or provide a link. (the surface roughness article doesn't) — Preceding unsigned comment added by 196.210.141.230 (talk) 14:29, 20 June 2011 (UTC)[reply]

There are really three concepts that are relevant to surface measurement: Surface roughness, surface waviness and surface form (most commonly surface flatness). All of these are measures of the deviation of a surface from a pure form or plane. Roughness is probably the best defined of the three measures but importantly: part of its definition includes the "cutoff width." Deviations from a plane are only included in the roughness value over the short distance of the cutoff width. 0.030" would be a typical cutoff value.

Waviness is the least well defined measure of surface geometry. It is essentially any deviation from a pure form that is measured over a distance greater than the surface roughness. See: http://www.everyspec.com/MIL-STD/MIL-STD+(0000+-+0099)/download.php?spec=MIL-STD-10A_NOTICE-2.010658.PDF

Surface Form can be flatness, circularity or in fact, any defined surface in 3 dimensional space. Flatness is defined to require that all points on a surface must fall between two parallel planes. Circularity, cylindricity and form are defined in a similar manner.

Lapping is a machining process that can be used to obtain all of the above requirements. But it's important to notice that the requirement for surface finish and the requirement for surface form are completely independent of one another. You can have a mirror finish on an abstract shape or you can have a rough surface on a part whose flatness is measured in millionths of an inch. --gargoyle888 (talk) 12:32, 22 June 2011 (UTC)[reply]