On Friday 12 August 2016 17:31:30 Ed wrote: > On 08/12/2016 03:39 PM, Gene Heskett wrote: > > On Friday 12 August 2016 14:24:19 Gene Heskett wrote: > >> Greetings all; > >> > >> At what temp do I have to get a piece of hot roll to in order to > >> soften the ultra hard core of the steel? Is it something this > >> toaster oven can achieve given enough soak time at about 425F? > > Add about 1000 degrees F to that for an anneal.
Which is why I ordered up enough stuff to make one of those $40 chinese 1kw gizmo's run today. > >> Doing the hole, which I haven't tapped yet, for the 4mm gib > >> adjuster screw last night, I started with a freshly DrillDoc > >> sharpened quality 3.44mm bit. > > Drill Doctors are not a high quality or high accuracy sharpener but > they are handy. They are known to leave a "heel" behind the cutting > edge, that might be your problem, give it some more clearance behind > the edge. I wore one of them completely out and am working on another. > I have 2, the 2nd, newer, smaller one is a POS compared to the original model. I see a couple shiny spots on the heel this time, I did not after the previous sharpening session and use on another piece of the same steel bar. I did get the hole tapped, but its sloppy. > > > I had much the same problem building the front clamp. Cold rolled > would work much easier, but I'd have to buy that online, whereas the > hot roll is in the bins at TSC. > > > Good hot rolled drills easier than CR, bad HR may have hard spots. I must never have had any good hot roll then. This stuff is horrible, even chips up brand new T'coated SC mills. > I > drill a LOT of both. If you have doubts about the quality cut part way > through with a hacksaw and bend it, and look for an obvious change in > texture This is obvious enough, it will dull a brand new Starret 32 tpi blade sawing off one 4.5" piece. The center 1/4x3/8 of a 1/2x1 bar may as well be diamond dust. > > I found a pdf, from ASM International, 18 pages describing in text > > and TT maps, what happens to steel as its heated and cooled. But > > somehow I am failing to make the connection to the temp, time at > > temp, and cooling rate to get the easiest to machine finished piece. > > For most low or medium carbon steel heat to 1450F and cool in the > furnace or if no furnace bury it in Vermiculite insulation to cool to > under 100F > > > Thats ASM #05144G. > > The fact that the TSC stuff carries no label describing its alloying > > materials and percentages is also "missing" info. > > Unless otherwise marked TSC steel is 1008 to 1018 steel alias A36. > > > I know in the early '50's that making the stuff drillable for cotter > > keys in the ends of some 5/8" shafting about 15" long was a matter > > of heating them pretty bright red on the ends, and air cooling, but > > other than necks of ammo being annealed for reloading longevity, > > that is about the extent of my knowledge if you throw in what you > > can do to a puddle of steel with a smith wrench. That is a whole > > science in and of itself. > > > > So, some recommendations, particularly for just the maximum > > machining ductility, and how best to measure that temp on the cheap, > > would be much appreciated. > > Heat with a torch to IHC tractor red and cool slowly, if you do not > prefer IHC then try Massey red. I thought that all came out of the same 55 gallon drum? I think, given enough time, this Chinese gizmo can do that from what I've seen it do on you-tube. Cooling slowly seems like a matter of turning the variac down over an overnight period once the target temp has been obtained, with what I have in mind. > > > Ed. > Thanks Ed. I'm a bit schmardter, I think. Time will judge that. > ---------------------------------------------------------------------- >-------- What NetFlow Analyzer can do for you? Monitors network > bandwidth and traffic patterns at an interface-level. Reveals which > users, apps, and protocols are consuming the most bandwidth. Provides > multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make > informed decisions using capacity planning reports. > http://sdm.link/zohodev2dev > _______________________________________________ > 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) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports. http://sdm.link/zohodev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
