Load DataRotoMetals2Lee PrecisionInline Fabrication
MidSouth Shooters SupplyTitan ReloadingReloading EverythingPBcastco
Repackbox Wideners
Page 5 of 8 FirstFirst 12345678 LastLast
Results 81 to 100 of 146

Thread: Adventures in top punch making (Long)

  1. #81
    Boolit Buddy
    Join Date
    Jun 2008
    Location
    Norteast Alberta, Canada
    Posts
    270
    JIMinPHX, I'll have to respectfully disagree with you on the engine oil thing.

    I actually agree with Willbird, in that you are better off with nothing (turning dry) and taking your time about it.
    I have used the stuff (engine oil) , and found it so lacking as to amount to being a detriment to progress.

    But, if it seems to be workin' fer ya... Probably somewhere near the origins of the phrase "your mileage may vary" came from, eh.

    A guy could do worse things than to try it and keep an open mind. I'd suggest trying it up against some of the other options, to see what works and what does not, though. Mmmmm! Bacon!

    Cermet's eh? Never touched them.

    The day I showed an old friend of mine how much nicer mild steel cut with a brushed on bit of soluble, though, I could have named my price for the bottle! He was using WD40 and whatever else he had around the farm shop, including engine oil, and had always figured that oil was oil... You could clearly see where the soluble mix had been applied in the progress of the cut. The finish went from horrid to pretty decent.

    If I am turning fast enough that the brushed on application does not stay put, I either need a flood system, or I need to rethink my strategy, but brush application is great for the slow, fine cuts that are for finish, usually, in a home shop. Business wise, if a guy has to consider whether brush application of a substitute for a proper coolant is a good idea, well, that business ain't gonna be around for long anyways, so... Home shop stuff should run at a different pace. The priorities are to enjoy oneself, as well as to make whatever one is trying to make, rather than to see the best cash return for ones time investment.

    The 5 gallon bucket for flood coolant is a great system, if your machine has a tray to catch the drippage, and the location allows you to splash a little around from time to time (domestic bliss isn't improved by stained ceilings, any more than by stainless swarf in the living room carpet, BTDT!). Even a gravity feed drip system or a squirt bottle is better than nothing, if you can use the help of a cutting fluid. I've seen one system where the guy used a homebuilt "bilge pump" style pump to transfer the coolant up to his header tank, a 2 gallon bucket with a soldered on fitting. Lotsa ways to skin that cat.

    Dairy creamer (not the "edible oil product" stuff, real cow) works pretty darn good for tapping copper, as well as for turning commutators. Just gotta lay out a couple paper towels to catch the drips, and rinse or wipe the parts down. That animal fats thing again.

    I like beeswax for tapping and drilling, if I cannot get any tapping juice. Run a wad of beeswax down the hole and the chips get pushed up as the tap goes down, then the remnants come out when you remove the tap. Works great!
    We use beeswax a lot for drilling out stainless and titanium rivets, too. Really improves the drill life! Just drill into the block, then to the job.

    Cast Iron and brass are best turned dry, and wearing eye protection (which you should be anyways!) for the flying dust and chips. Good cast iron is a joy to machine, but filthy, and poor cast iron, is pretty much the exact and total opposite, full of hard spots and inclusions. Most brass is as nice. Some of the bronzes are decent, some will make you want to take up other hobbies.

    Anyhoo. Sorta rambled on a bit... Hey. It happens!

    Cheers
    Trev

  2. #82
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    Quote Originally Posted by lathesmith View Post
    parting off, another one of those handy "lathe arts" that needs to be mastered. ...
    lathesmith
    Aside from good lubrication, one of the big things that helps parting off operations work well is a good rigid tool holder. Aside from some of the expensive stuff from people like Manchester, most parting tool holders are really substandard for the job at hand. Even the ones from Aloris are a bit on the flimsy side & have been known to throw a tool across the room. I usually make my own parting tool holders from scratch.

    Parting & knurling are probably two of the most brutal operations that you will encounter on a lathe. They require good tools.
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  3. #83
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    Quote Originally Posted by trevj View Post
    JIMinPHX, I'll have to respectfully disagree with you on the engine oil thing.

    Cheers
    Trev
    Fair enough sir.
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  4. #84
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    Quote Originally Posted by trevj View Post
    Dairy creamer (not the "edible oil product" stuff, real cow) works pretty darn good for tapping copper, ...


    We use beeswax a lot for drilling out stainless and titanium rivets, too. Really improves the drill life! Just drill into the block, then to the job...

    Cast Iron and brass are best turned dry... Good cast iron is a joy to machine
    Cheers
    Trev
    I've used bacon grease a few times, but I did not know that cow juice could also be used. That's a new one on me.

    I've seen guys use hard lube the way that you describe using the bee's wax. I'll have to try that sometime. I would be surprised that it would be good for SS or Ti, but hey, I haven't tried it yet, so I don't know. I'm always looking to learn.

    Ti can be a real finicky material to work with. It is fussy about what lubricants it likes. Most of the ones it does like are flammable. Once Ti catches fire, you can't put it out. If you don't keep it cool enough when cutting it, it develops instant hard spots. You need carbide to get through the hard spots, but HSS generally cuts it better if you keep it annealed. I could go on for about 3 pages on welding that stuff too. It's not a good material for the beginner to start with. It's worse to work with than Hastaloy.

    I'll agree with you about turning cast dry. I'll disagree about going dry on copper alloys. I use fluid with them, but I also use a very shallow clearance angle on my cutting surfaces to avoid having the tools getting sucked into the work.

    There is almost always more than 1 way to skin a cat when it comes to machining. Different people have different approaches & more than 1 will usually get the job done.
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  5. #85
    Boolit Master

    Join Date
    Mar 2005
    Location
    NW Ohio, almost as N and W as you can be :-)
    Posts
    2,915
    Having the cutting oil there to varying degrees causes a different finish as trev pointed out, so if you look at the finish afterwards it looks like this ___-----___-----------____--__-----__-- on the surface because part heating and chip flow changed the amount of lubrication. You can also get the same thing if you turn a part say 1.01", then rub your finger on one spot while the lathe is running, then take off .01". often the spot where the oil from your finger is will have a different finish.

    Without a heavy flood the only lubricating film condition I can control is NONE . I use a little Brownells do-drill on drills, taps, and reamers...I'm pretty sure that stuff is Rigid black sulfur threading oil, but a quart of it has lasted me for darn near 10 years so I'm not in a hurry to undercut brownells on price any time soon .

    When I started in the trade running screw machines and turret lathes they generally used straight cutting oil, one type for steel and another type for brass/bronze...it works really well, but it is messy and the parts need washed afterwards....I ran a cnc mill once that was using straight steel cutting oil, we went through 55 gallons a week and it even had a full enclosure. You also have to centrifuge the cutting oil out of your shavings afterwards too.

    With modern machines the fluid is merely a COOLANT....it's lubricity is needed for tapping and reaming but the cutting tools do not need it, in fact DRY milling is becoming more and more common. If you use a coolant on a MILLING tool the nature of the cutting causes a thermal cycle on the cutting edge, it gets hot as it forms a chip and cools when it exits the cut. With large inserted saws say 6" in dia and 1" wide you can hear that the cut sounds better DRY than with coolant. But often times the coolant is needed to keep the part cool for dimensional and work hardening reasons.

    I have used the "micro drop" dispensers several times, they work REAL nice on a band type cutoff saw. The lubricant they use is quite often just canola oil.

    Bill
    Both ends WHAT a player

  6. #86
    Boolit Buddy
    Join Date
    Jun 2008
    Location
    Norteast Alberta, Canada
    Posts
    270
    I have a Myford lathe at home, and get to play with some 15" swing lathes at work, as well as a superlative toolroom machine of about 12" swing.

    All the machines at work run coolant. At home, my machining style has to change rather a lot.

    At home I mostly turn dry, except for, as I said, fine finishing cuts, and threading. For that, the brushed on soluble works pretty well.

    On parting off. Most guys fear it, it seems. I have parted off 3" mild steel on my Myford. It's nothing special, as lathes go (rather the opposite, actually), and the toolholder was not either. I found that being more aggressive with the feed, was better, as long as the infeed was smooth. Pretty much a matter of getting a feel for it, and not going too slow. Hard to describe, easy to demonstrate...I can only recall breaking one parting tool on the Myford, and that was when I was turning the part too slow, and got a dig-in... Again, really hard to describe, pretty easy to show.

    At work, I almost always part off with the power cross feed, a luxury my home machine does not have. But for real fun....I had to part off a bunch of Aluminum Bronze spacers from a bar last week. 3000 rpm and near a thou per rev feed rate. It spat a ribbon of bronze into a pile about three feet behind me, where I was standing in front of the lathe. At the other end of the scale, I have made parting tools as narrow as 20 thou wide, to part off very small bushings from the parent bar, when the stock supply was low and I did not wish to convert all of it to chips. Substantially different yield when you are not cutting .100 wide grooves to build a .040" spacer out of 1/4" stock.

    Dry machining. I see some of the CNC videos online and am in awe of the rates of metal removal that are achieved with small end mills (typically 1/2") and a fast spindle. And that the residual heat is near nothing, in both the tool and the part. Right out of the realm of the home shop guy for the most part. Heck, right out of the realm for the shop at work, too!

    For the home shop guys. A quick change tool post of some sort. Build one if the budget is not there to buy one! Lots of info around the web. I'm about half finished on a tool post that looks very similar to a Tripan one, for my Myford.

    It's very nice, to be able to switch to a threading tool or a parting tool, and not have to fiddle to get the angles and tool height all set right every time!

    Cheers
    Trev

  7. #87
    Boolit Master Cap'n Morgan's Avatar
    Join Date
    Jun 2008
    Location
    Denmark
    Posts
    1,457
    Parting & knurling are probably two of the most brutal operations that you will encounter on a lathe. They require good tools.
    If the lathe isn't quite up to the job of parting, try running the parting tool upside down. Instead of the cutting force acting upwards - trying to "lift" the part and the chuck - it will act on the whole carriage, which is heavier and more stable than the chuck - especially if the bearings are worn. Also, the chips will be less likely to clog the cut. Oh, and remember to run the spindle in reverse...

    Knurling is best done with at double roller tool like this:http://www.lautard.com/Caliperknurlingtool.jpg Much easier on the part as the force is balanced between the rollers.
    Cap'n Morgan

  8. #88
    Boolit Master

    Join Date
    Mar 2005
    Location
    NW Ohio, almost as N and W as you can be :-)
    Posts
    2,915
    One thing that happens with parting tools is if your lathe has a LOT of backlash in the crossfeed screw the parting tool sucks itself into the work. Then the parting tool breaks with a BANG, and the broken pieces CAN fly up and break the 48" floursecant tubes in the light above the lathe. When it is dark out and all of this happens plus that was the ONLY light on in the building much cursing happens right afterwards .

    Bill
    Both ends WHAT a player

  9. #89
    Boolit Master
    lathesmith's Avatar
    Join Date
    Nov 2006
    Location
    Springfield, Missouri
    Posts
    1,373
    Parting is definitely one of the trickier things to master, it seems, as far as lathe operation goes. What works on one lathe may not work on another; different materials have their own requirements, and so on. For me, parting aluminum is a breeze, brass is simple, mild steel isn't too bad, but drill rod is the trickiest. The closer you part off to the spindle head, the better. As for spindle speed, too fast is as bad as too slow; ditto for in-feeding your tool. And, you need something that both lubes and cools for optimum results. Since I leave my gear box disengaged most of the time, I don't power in-feed, although this can be a helpful thing to do.
    I have learned to stand well away from the parting tool while in operation. It seems that in reading about guys learning to part off in the old days, there were lots of one-eyed lathe operators, nearly all from the time when they learned to part off. Of course, one should always,always, ALWAYS have safety glasses on while working in the shop, and this is just a reminder. Even the best of operators will hang and "pop" one of these things every now and then, if much parting is done at all.
    Like Cap'n Morgan, I have come to much prefer the scissor-type knurlers as these distribute the forces of knurling and I seem to be able to get a better knurling job with them anyhow.
    lathesmith

  10. #90
    Boolit Master

    Join Date
    Mar 2005
    Location
    NW Ohio, almost as N and W as you can be :-)
    Posts
    2,915
    Rigidity is the real key to parting off. On a turret lathe or a screw machine it works slicker than snot on a brass doorknob. Those of course are very rigid machines.

    Bill
    Both ends WHAT a player

  11. #91
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    Quote Originally Posted by Willbird View Post
    DRY milling is becoming more and more common.
    Bill
    Yea, with cold air guns, proper (expensive) coatings on the cutting tools, good rigidity in the machine & properly controlled feed & spindle rates. I'm not going to give Lathesmith a hard time for wanting flood coolant on his home rig, but I think that high speed dry systems are starting to get a bit out of the box on what is feasible for a common home shop.

    Just me $0.02
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  12. #92
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    After all this talk about parting off, nobody seems to have mentioned one of it's key values. It is one fast way to get a good square cut with a good finish. Even on a little 10" lathe, I can part off a piece of 2" 6061 in about 10 seconds as long as I keep the juice pouring on it good. It would take one heck of a mean bandsaw to even come close to that. Even a Scotchman cold saw has trouble keeping up with a good parting tool.
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  13. #93
    Boolit Buddy
    Join Date
    Jun 2008
    Location
    Norteast Alberta, Canada
    Posts
    270
    I've got decent surface finishes on my machines at work, parting off with flood coolant. On my Myford, esp. on mild steel, not so much... But it sure beats hacksawing!

    I've been pondering (among way too many other prospective projects!) building a cut knurling tool holder for use at home.

    The factory built ones are priced stupid expensive, but I figure a guy with some time on his hands, and some suitable stock, could make one, and either buy the knurl cutters, or modify regular ones (maybe less satisfactory, but definitely cheaper!) to get the end results wanted.

    Scissor knurling tools and squeeze knurling tools are pretty good, and there are lots of designs available out there.

    A guy can do worse things than to familiarize himself with some of the tooling used to do various operations on the small turret lathes, too. Lot's of really good ideas there for getting seemingly impossible jobs done. Box tools as a prime example, for a guy that wants to build a long shaft or turn a long rod to diameter.
    Looking over the tool catalogs for swiss screw machines is where I found out about cut knurling tools...
    Some of that "obsolete" technology still has a lot of life left in it!

    Cheers
    Trev

  14. #94
    Boolit Master

    Join Date
    Mar 2005
    Location
    NW Ohio, almost as N and W as you can be :-)
    Posts
    2,915
    Quote Originally Posted by JIMinPHX View Post
    Yea, with cold air guns, proper (expensive) coatings on the cutting tools, good rigidity in the machine & properly controlled feed & spindle rates. I'm not going to give Lathesmith a hard time for wanting flood coolant on his home rig, but I think that high speed dry systems are starting to get a bit out of the box on what is feasible for a common home shop.

    Just me $0.02
    Actually many users are just using plain old compressed air to blow chips out of the cut zone, tool geometry makes the heat stay in the chip and not the cutter or the work.

    One thing about knurling that I never thought about until it was pointed out, a knurl should FIT on the part to work correctly, the situation is just like gear teeth, if the pitch of knurl does not fit the circumference of the part it will only work so-so. This explains why sometimes when we knurl we get such a nice job, and other times it gives you fits . I think the proper pitch of knurl would be more important with a cut knurl than a swaged one, or maybe not ??

    Bill
    Both ends WHAT a player

  15. #95
    Boolit Buddy oldtoolsniper's Avatar
    Join Date
    Feb 2009
    Location
    Iowa
    Posts
    449
    I can't believe all the stuff I am learning. I joined a 109 lathe site and I am lucky if something is posted once a week.
    “Work hard! Millions on welfare depend on it!”

  16. #96
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    Quote Originally Posted by Willbird View Post
    One thing about knurling that I never thought about until it was pointed out, a knurl should FIT on the part to work correctly, the situation is just like gear teeth, if the pitch of knurl does not fit the circumference of the part it will only work so-so.
    Bill
    I've had times where I've intentionally knurled at a diameter that would give me a double cut, so that I would get a finer knurl with a coarse knurl wheel. I've also done it by accident more times than I care to admit.

    For knurl applications, where you just want to give someone a surface that they can grip with their hand, I usually just cut a surface, then knurl & see if it looks good. If it does, great. If it doesn't, then I skim about .010" & have another go at it. For applications where the finished diameter of the knurl matters, like a driven roller on a printing press that controls web registration, you don't have the luxury of pulling that kind of stunt.
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  17. #97
    Boolit Grand Master JIMinPHX's Avatar
    Join Date
    Aug 2007
    Location
    Moving back east now
    Posts
    5,089
    Quote Originally Posted by oldtoolsniper View Post
    I can't believe all the stuff I am learning. I joined a 109 lathe site and I am lucky if something is posted once a week.
    When you get bored with top punches, You might give this a try -
    Attached Thumbnails Attached Thumbnails Lyman Die Blank.JPG  
    “an armed society is a polite society.”
    Robert A. Heinlein

    "Idque apud imperitos humanitas vocabatur, cum pars servitutis esset."
    Publius Tacitus

  18. #98
    Boolit Master

    Join Date
    Mar 2005
    Location
    NW Ohio, almost as N and W as you can be :-)
    Posts
    2,915
    Quote Originally Posted by JIMinPHX View Post
    I've had times where I've intentionally knurled at a diameter that would give me a double cut, so that I would get a finer knurl with a coarse knurl wheel. I've also done it by accident more times than I care to admit.

    For knurl applications, where you just want to give someone a surface that they can grip with their hand, I usually just cut a surface, then knurl & see if it looks good. If it does, great. If it doesn't, then I skim about .010" & have another go at it. For applications where the finished diameter of the knurl matters, like a driven roller on a printing press that controls web registration, you don't have the luxury of pulling that kind of stunt.
    One thing I have learned the hard way is that a super smooth turned finish does not HELP knurling any, and in fact setting your feed rate to .01 to .015 per rev for the finish pass before knurling usually results in a nicer knurl.
    .
    In general I use higher feedrates, there is generally no benefit in running the .0006 or .0012 feeds many lathes run on the bottom end (often you are only feeding 1/2 that when facing)...typically I run at least .005 for general turning.....to a degree the slower the feed rate the more heat goes into the tool and the work.

    I do not like to use abrasives to acquire a finish unless strictly needed, but I have no aversion to knocking the fuzz off with a nicholson mill bastard file.

    Bill
    Both ends WHAT a player

  19. #99
    Boolit Master




    badgeredd's Avatar
    Join Date
    Feb 2008
    Location
    there, not here
    Posts
    2,306
    Quote Originally Posted by oldtoolsniper View Post
    I can't believe all the stuff I am learning. I joined a 109 lathe site and I am lucky if something is posted once a week.
    oldtoolsniper,

    As a carrer tool maker, I can honestly say that there are dang few days that I haven't learned a new way to do just about anything. Often there are at least a half dozens ways to get it done, none wrong. Some will be just better for you.

    Thanks for the laugh, well written and FUNNY! I do recall many humorous happenings watching newbies learning to operate a new to them machine. I also have to say that most of the pros I've worked with, can tell stories for hours.

    BTW, for tapping there is some pretty neat stuff out there to be had. My personal preference is Tap-magic. It is a synthetic machining fluid. Too expensive to use on everything, but great stuff to have around.

    Edd
    Charter member Michigan liars club!

    "The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in Government." -- Thomas Jefferson

    "Consider the clown(s) just one of God's little nettles in the woods, don't let it detract from the beauty. Sooner or latter you are going to run into the nettles regardless of how careful you are."

    Beware of man who types much, but says nothing.

  20. #100
    Super Moderator




    Buckshot's Avatar
    Join Date
    Mar 2005
    Location
    So. California
    Posts
    11,833
    .................JIm old bean, that print looks awefully like an RCBS lube-size die vs the Lyman Just being picky!



    Unless you're running a big ole American Pacemaker or similar, a scissors knurl is the only way to go. A bump knurler would probably bust the compound off my Logan!



    I've never had much of a problem parting off whether big steel left (3" is big for me) or bitty steel right. The only problem with such large OD's, and 3" is the largest I'd ever done, is the time to extend the tool and ease off on the feed. The guy I bought my lathe from uses a hacksaw. I pretty much use the carbide insert type parting blade anymore.

    One of the benefits of inverting the parting blade and having the material rotate UP past it is that it lifts the cross slide and the compound up into their dovetails, vs down and away. Pulling them up removes all the clearance required for them to move along the dovetails. And lets face it, almost all the wear to the cross slide dovetails take place on the front half. I seldom use the compound for anything other then threading so it remains sitting at 29.5* with it's gibb screws locked down.



    Parting with the 'T' blade. As it's HSS and can carry an exceedingly sharp edge it works best (for me anyway) like here when the piece is extended out. The light cut produces a long razor sharp ribbon across the top of the tool. The carbide insert turns the chip into a 'V' which breaks up into smaller curly pigtail type chips. The carbide will also produce a mirror like finish if cutting oil is run on it while parting (if you need that).

    ...............Buckshot
    Father Grand Caster watches over you my brother. Go now and pour yourself a hot one. May the Sacred Silver Stream be with you always

    Proud former Shooters.Com Cast Bullet alumnus and plank owner.

    "The Republic can survive a Barack Obama, who is, after all, merely a fool. It is less likely to survive a multitude of fools such as those who made him their president."

    Shrink the State End the Fed Balance the budget Make a profit Leave an inheritance

Page 5 of 8 FirstFirst 12345678 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check