On Wednesday 06 January 2021 23:46:36 TJoseph Powderly wrote: > Hi Gene > you can buy Prussian Blue oil paint tube from an art store or internet > you can get a pretty good surface plate from a cutout of a kitchen > sink granite top
I have a surface plate but its triple the weight of this mill. 4" thick, 12" x 18" Feels like around 80 lbs to me, but I could just be getting old. :( > you can measure the flatness with this old trick > takes 2 123 blocks a mag indicator stand and an indicator > mount indicator to stand and clamp stand onto large surface of 123 > place both 123's on surface to check. You can 0 indicator onto the > plain 123. as you move the pair over the surface you are measuring the > avg 123 area height to the other 123 area height. You make a map of > the results on paper. I'll have to locate a granite peddler for the light weight version, and get the 123 blocks. Good idea though. Thanks TomP. > This will show you how flat the surface is. > this is an independent measure ( the surface may not be parallel to > the x or y rails > but it is important to be able to what element is contributing what > part of error to the wkpc. > > stay safe, god bless america > After today, I'm not so sure he is blessing us. We'll see that happens in the next 14 days. > tomp > > On Thu, Jan 7, 2021 at 7:08 AM Gene Heskett <ghesk...@shentel.net> wrote: > > On Wednesday 06 January 2021 18:45:11 Jon Elson wrote: > > > On 01/06/2021 04:30 PM, Gene Heskett wrote: > > > > On Wednesday 06 January 2021 06:08:23 andy pugh wrote: > > > >> How far out of true is it? > > > > > > > > A good mm in some of the places I have checked. But now I need > > > > to stay at or below .1mm over a foot of travel for this box mod. > > > > I could reclamp it, and survey it with my throw away > > > > renasys(sp?), but am trying to get enough data I don't have to > > > > do it over for each piece I make. > > > > > > Well, there is always hand scraping. I've never done it on > > > aluminum, but I'd guess it might > > > be very similar to cast iron. But, of course, if putting > > > clamps anywhere distorts it more, then > > > it is kind of a losing battle. > > > > > > All you need is a known-flat reference surface like a > > > granite surface plate, some blue dye > > > and a scraping tool. You can make scrapers out of large > > > carbide cutting inserts. While > > > Dy-Kem Prussian Blue dye is the best, it is very messy, so I > > > recommend Canode spotting dye. > > > That is water-soluble. > > > > Never heard of Canode till now. Msg marked, thanks Jon > > > > Cheers, Gene Heskett > > -- > > "There are four boxes to be used in defense of liberty: > > soap, ballot, jury, and ammo. Please use in that order." > > -Ed Howdershelt (Author) > > If we desire respect for the law, we must first make the law > > respectable. - Louis D. Brandeis > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users