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    Tool setting in shops. Dedicated setter vs in machine

    . optical tool setter advantages . 1) in theory you can be doing tooling while the cnc is running, its one thing only a few tools but if doing 10 to 40 tools it can be time consuming obviously . 2) optical tool setter usually has a way to calibrate whether a test bar tool or it looks at base of...
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    How fast (SFM) can you run HSS in 6061?

    many factors like length of tool stick out tool holder length (flexing vibration damages carbide faster than hss) depth of cut width of cut part material part stability, fixture stability desired finish coolant or dry tool life sfpm ipt feed ..... router speeds often run very fast, same with...
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    Circle Adjusted Beyond Maximum Adjustment

    if not a tool comp issue sometimes control . 1) doesn't like full circle, some controls need to do circle in 4 parts 2) sometimes the math is off, I have seen where control wouldn't accept numbers but changed numbers .001 mm and then it would. how math is off ? don't know but I have seen cnc...
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    LPS PreSolve Orange Degreaser worth the price?

    Simple Green cleaner comes in $10. gallons and often works fairly good removing dirty coolant with oil in it coated parts, need to change rag / wiper often, other wise just rubbing part with dirty rag its just moving it around not wiping it off
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    Strange tearing/surface finish Titanium facing - Pics included

    ..... could be crappy metal or some cutters you get a shiny mirror like surface above certain sfpm (a lot higher sfpm) ........just saying sometimes 10 or 20% adjustment often dont see everything and might need much larger changes to gather info and or find limits. thats and tool life some...
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    sagging of ferritic gray iron

    . usually cast iron distorts, bends after machining after temperature stabilizes and hours or days pass. it tends to stop warpage or distortion after that. . steel and stainless also I have seen bent to straighten and next day, it bent back some. why ? old timers would shrug and say metal had...
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    Are people scared of Advanced manufacturing technology? Practical Machinist asked the question. Let’s discuss.

    what to worry about ? .... most workers just get laid off and find another job. I would think boss or business owner would worry more about new technology but many businesses deliberately split company up so parts of company can declare bankruptcy (legally not pay 100% of debts) . taxes and...
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    Gauge block conditioning stones

    from my experience 600 grit you might need to lap 10 times to remove about .0001" . 1000 grit and finer is more for polishing, 4000 grit good luck removing even .00001" even if you wanted too. most gage block that dont wring were used for check slot sizes, forcing blocks into steel slot probably...
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    What CAM systems incorporate Chip Thinning into their feedrate calculations?

    obviously high feed rates cnc does not follow programmed path as accurately. over 100 ipm feed many cnc are easily over .0010" following the programmed path and .003" error not unheard off . many try increasing feed til it gets noisy, but i have seen where over .007" was needed to finish the...
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    Gauge block conditioning stones

    i rub gage blocks on post it notes paper to clean, if edge needed stoning i could see doing that. . actual lapping you could try lapping film on a surface plate so film was flat. usually 1000 grit or finer lapping film feels like paper (if paper based) or if plastic film doesnt feel abrasive...
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    Deep Drilling Help

    . try a .250 drill over 18" deep it can be a problem breaking drill and not being able to get out. . many drills have a back taper where flutes by shank are .002 to .020" smaller diameter. . or go in with .500 deep as comfortable as you can and finish with a smaller drill like .485 the...
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    Best tool for achieving a deep milled finish (Such as those of a milled Putter)

    . facemill with 1 or 2 or 3 inserts V shaped, then a G81 drill mode straight down then up and over for next like G81 X0. Y0. Z-.010 R0.2 F3.0 X.1 X.2 X.3 etc G80 stop cycle .... often done 2 ea surfaces 5" wide by 40" that later get moglice or a type of epoxy coating like turcite, the pattern...
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    Toyoda FH80B horiz mill fanuc 15M program skipping program line question

    . I gave often seen G4 P10000 M99 . the delay (P is milliseconds) before the M99 helps sometimes a slow control
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    Lapping compund to use and amount

    . how much depth you lapping .0002" ? . how big the blocks 2x2", 10x10", 40x40" ? . small parts I sometimes use a sheet of sand paper on a surface plate or use stikit adhesive backed sand paper on a ground steel block . 180grit will take .0001 or .0003" enough to sand off mill marks eventually...
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    G83 question..?

    its a parameter on fanuc 15 machines. big drills even 0.100" not enough if chips still in hole if you got 2" or 3" dia drill rapiding back in, chips compress at bottom of hole, drill acts like rapid collision at hole bottom. when its borderline you get the crunching bad sound which aint good for...
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    Granite surface plate accuracy

    granite squares get checked like anything else, 36" granite squares i use are within .0001 per 36" . some are marked on edge per inch with a type of ruler sticker. so you can lookup error say at 10" mark might say its -5 or -5 millionths there at 10" mark . the original manufacturer can probably...
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    Chinese Cast Iron extremely dirty, even by C.I. Standards

    . every foundry is different and different pours of iron can be different. I have seen this world wide . machine a few 1000 tons of iron you might see differences. .....some iron poured too hot in a arc furnace can be soft and have a type of porosity. the same iron in other castings from same...
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    Why scrape when you can grind?

    also grinders produce heat and coolant is often at a different temperature. . I have often seen one end of a large 6 foot long part change height .0003" cause coolant only hitting or covering the end of the part being machined, if measure quickly then measure a hour later you see the height...
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    Why scrape when you can grind?

    yes casting can warp or curl over time or at a different temperature, if on a surface grinder if using a magnetic chuck vise table if magnet is turned off and part curls .001" per 40"..... . obviously need to support part in its relaxed curled or bowed shape and then confirm magnetic field...
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    Are all the old Thread pitches still needed? Thread per inch, and some odd metrics.

    . I have used 127 tpi for steel screw, making a tap and a "split brass nut" that is tightened to grip screw tight. the threads are so fine they dont look like threads more like a medium coarse turning . the front of sharp V cutter (not top) is forced into metal it basically is knurling or cold...