It's Alive! It's Alive!

[Char-Gar]

OK, I now have a working lathe. It whirs, hums and makes assorted lathe noses. I don't know what it is supposed to sound like, but I don't hear anything that makes me think..bad bearings or oh crap..so I guess I am good for now. Now begins the dumb newbie questions.

1. What is the best speed for general turning, of steel? How about drilling and boring?

2. Tell me about these dumb back gears. They spin just fine, but when I lock them into the other gears in the headstock, nothing will move. I am certain there is a simple answer, but I don't know it.


As always, thanks for any help you can give.

[uncle joe]

If you're new to machining, I suggest you find a copy of "the machinery's handbook", it's a little book that is about as thick as it is wide, and let's just say, if it ain't in this book you probably don't need to know it. It has everything in it from machining questions like tht one you have to volumes of objects, screw thread dimensions pipe sized, heck it has it all.
UJ

[uncle joe]

if you like Amazon like I do
http://www.amazon.com/s/qid=1240688803/ref=sr_pg_2?ie=UTF8&rs=&keywords=machinery%27s%20handbook&rh=i%3Aaps%2Ck%3Amachinery%27s%20handbook&page=2

[KCSO]

Chargar
The back gears are only engaged when the head stock pin id dis engaged. Cutting speed is figured by how much material you are removing from what. A good machinery hand book will give you some good starting places and expirience will teach you some more. You will use the back gears mainly for knurling and threading. In general you cut brass and aluminum at a faster rpm than steel. Just to give you a starting place w/o having tocrunch the numbers on my South Bend I use the lowest speed w/o back gears for most steel cutting and the highest speed for finish cuts in aluminum.

[fishhawk]

there is a little pin there to disconect the head from direct drive pull that pin and the head stock will turn free then engage the back gears and it will cut the head stock speed wayyyy down. steve k

[JSnover]

Your speed will also depend on the diameter of the piece. You'll want to slow down for larger work because of the higher surface speed. If most of your parts are under an inch or so, it may not be much of a problem. For threading, knurling and especially parting you'll want to go a lot slower.

[badgeredd]

............... and especially parting you'll want to go a lot slower.

Sounds like experience speaking to me. :-D:-D:-D


Edd

[JSnover]

Oh yeah! It makes a pretty distinctive sound when the tool digs in and snaps off, LOL!

[Char-Gar]

As Gabby Hays used to say... " Y I be hornswageld" if I can find any pin on that headstock. I have looked and felt very square inch of it.

The backgears will turn freely and so will the headstock gears. There is a lever on the left side of the headstock you turn toward you that will mesh the back gears and the gears in the headstock. This works as smooth as you like and the two gearing system mesh like they were made for each other. Which they were.

OK.. now I have the back gears engaged with the spindle gears.....nothing will move..I mean the whole she-bang is locked up solid. Turn the lever away from you, and the back gears move out of mesh and everything turns both directions hunky dorry.

I don't understand why the back and spindle gears work just fine until you mesh them together and them the whole lathe locks up.

[Char-Gar]

Sorry boys, but that book is too rich for my blood. I have to keep asking around and googling.

[Char-Gar]

OK.. I broke the code. There IS a pin on the side of the bull gear that locks the bull gear into the pullys and spindle gears. When this pin is in the the back gears endgaged, everything locks down. If you pull out that pin and free the bull gear from all of the others stuff, away you go running on back gears.

Now the next problem to solve, is when running on back gears, the assembly wants to move rearward and disengage.

OK.. solved that one also. The newer Logan lathes have a pin that holds the back gears either out of engagment or in engagments. Mine doesn't have that. Sooo.. a big rubber band around the back gear lever and stretched to the reverse handles does the job. Enough tension to hold the back gears in place, but not enought to move the reversing lever.

On the slower motor pully, I can gets speeds of 55-80-112-335-457-645 (The three slowest on the back gears of course)
On the faster motor pully, I can get speeds of 114-200-831-1157-14-5 (Again the three slowest on the back gears)

It is a real PITA to change the belt on the motor pully as you have to loosen the motor on the countershaft. Most of that working blind by feel behind the lathe. It can be done, but I think I will just leave it on the slower pully uless I really need the higher speeds, which I gather from you guys I won't be needing often.

[JSnover]

I'm not a huge fan of ebay but you can get used copies there for a pretty reasonable price. Don't worry if it's not the latest edition, at this point you just want to master the basics first.

[Pavogrande]

Machinery's handbook is great source of info, but not on "how to run a lathe" - Try to find an older south bend "how to run a lathe" or Atlas/craftsman "lathe operation and Machinists Tables" -- Perhaps Logan had a similiar book -- These manuals are much more useful for learning how to operate the lathe -- my ha-penny

[jhrosier]

Sorry boys, but that book is too rich for my blood. I have to keep asking around and googling.

I found a couple of listings on amazon.com for $15 + 3.99 S&H

http://www.amazon.com/gp/offer-listing/0831111550/ref=sr_1_olp_14?ie=UTF8&s=books&qid=1240696365&sr=8-14


Jack

[deltaenterprizes]

Try going over to"The Home Shop Machinist" web site.

[Gunfixer]

How to run a lathe @ brownells for $7.95
# 100-001-043
Lindsay publications reprint of South Bend.
I can run a lathe but I dont know how to post a link

[RayinNH]

Chargar, try the local used book/second hand shop, or even the local library. A book that is 50-75 years old will answer many of your questions...Ray

[dragonrider]

"The Home Shop Machinist" +1 on that, the info you need you will find there.

[dpaultx]

Here's a nice little machine shop reference book that you (and all the rest of US) have already paid for and that you can get your very own copy of for FREE.

TC 9-524, "Fundamentals of Machine Tools" is a fairly comprehensive Tech Manual put out by the United States Army covering the operational basics of not only a manual lathe, but also the operation of just about every other piece of equipment found in a typical machine shop.

This link at www.metalworking.com (http://www.metalworking.com/tutorials/ARMY-TC-9-524/9-524-index.html) allows you to download the entire book or just individual chapters of the book in PDF format. Chapter 7 cover basic lathe operations and is 68 pages long by itself. Most all of it will apply to just about any typical machine lathe.

The three Appendices covering Tables, Weights and Measures, and Formulas also contain very useful info.

It's a lot of info to download, but it really is a great reference to have. The Army tech manual was last updated in 1996 which is fairly current by machine tool standards.

HTH . . . Doug

[deltaenterprizes]

The very FIRST thing you need to learn is LATHE SAFETY, so that you do not loose any fingers, an eye or get pulled into the lathe up to your shoulder with your arm wrapped around the chuck!
After safety you need to learn how to sharpen a tool, if it ain't sharp it wont cut, like trying to whittle with a dull pocket knife.
The next concept is: Surface feet per minute = work diameter x RPM = 4/dia in inches/12

SFM for High Speed Steel:
Aluminum 200-400
Mild Steel 80-100 1018
Stainless Steel 40-60
grey cast iron 50-70
The basic theory is harder the material the slower you spin it.

[lathesmith]

Chargar, there is some good reading advice here, and also do some web searches, there is also quite abit of info out there about SFM and other neat stuff.
As a general rule of thumb, the smaller the bit, the faster you run it. On the lathe, anything in the 1/4" drill bit and smaller vicinity I generally use about 600 rpm; by the time I have hit 1/2" I drop speed to around 450-500 rpm. Mind you, this is just my setup, yours may vary; I have experimented some with different speeds and this is what I use.

For turning steel, either mild or tool, for stock that is 1" or less, I generally use 1000 rpm or less. For deep roughing cuts, say .060 or more, I'll slow things down to 500 rpm or so; for light finishing cuts of .010 or less, the faster you can run the better.
Just my few cuttings' worth....
lathesmith

[Dutchman]

1. What is the best speed for general turning, of steel? How about drilling and boring?

No.1 - learn to grind HSS bits in the most basic forms. Lots of references that'll show this. Rake angle and relief angle are terms you need to know. The absolute cutting tip must be on centerline. A super simple rinky dink way of doing this is have a piece of pointed steel in the tailstock chuck. That's the point you can use to adjust your tool height to centerline. (remove the pointy flesh gouging item afterwards).

Tool angle geometry is where you should put some time learning. Its really kinda interesting and utterly required if you expect to do anything resembling a smooth finish on any type of material.

After you grind your HSS bit then you work it on an oil stone to remove the grinding striations. I use a very old India stone with coarse on one side and smooth on the other. It was the stone my father used to sharpen knives and is about 60 years old. Always use oil on the stone. You can get a near mirror finish on HSS this way and your grind job will last longer if you treat it nice.

No.2 - Speed. Start slow. I do a lot of low carbon steel in the 250-350 rpm range and this is with stuff under 1.5" diameter. It doesn't take speed to get a good finish. It takes technique. A big lathe.. 3,000 lbs.. can do pretty decent finishes at 150 rpm because of machine rigidity.

Same goes for drilling. Slow first. Use oil. Motor oil does as good a job as anything. It doesn't smell as good as sulpherized coal oil but neither of them will do your lungs any good. But still... motor oil for drilling or turning is ok-fine. Use an acid brush and keep a little tuna can of oil on the cross slide... right where you can always knock it off and spill. If it doesn't smoke your speed is too slow. If it smokes a lot the speed is too fast. That's college level knowledge there[smilie=1: . My college machine shop teacher was a Navy Machinist Mate during WW2. He was good, very good. US Navy Machinist Mates are among the best general machinists you'll find. They don't have the luxury of sending work out that they can't do. Those words aren't allowed. Can do. Have to do. Make do. Find a way and do it.

Don't try to do any threading until you get some time in on the machine. Then first few times threading use a slow back gear speed and give yourself permission to make mistakes.

Machines will communicate with you. They'll talk to you if you know the language. Too fast and they tell you. Too slow and they tell you. You do something really bad and you'll break something. You'll listen closer next time. Every machine has its own tongue. Treat it like a living being and it'll treat you better. Hate to say this but I'm in Northern California and we're expected to say things like this:
Zen and the art of lathe turning. Learn it. It exists. The lathe is an extension of your creative mind. Become ~one~ with it and an intimate relationship between your eyes, brain and fingers will develop. Incredible images will manifest in your mind's eye (the 3rd eye) with only faint hints as to how to make the journey from nothing to something. Once this starts to happen your life will change. It'll never be the same again. Trust me. I know these things.

Don't work with any chip-making machinery without safety glasses or glasses of some kind. You wanna know what a hot chip feels like in the eye? (no, you don't).

If you want to see some zen lathe art:::::::::::
http://heetgasmodelbouw.ridders.nu/index.htm

http://www.frets.com/HomeShopTech/hstpages.html

http://vts.bc.ca/metalshop/hobber/hobber.htm

http://www.duncanamps.com/metal/projects/quorn/index.php

http://riceone1.com/id1.html

http://www.rulezman.com/workshop/ws/friends/knurlingtool.htm

http://homepage3.nifty.com/amigos/index-e.html

http://www.tools-n-gizmos.com/specs.html

Don't neglect the inspiration of the houtdraaijer as a source of parallel experience.
http://www.de-houtdraaier.nl/projecten.htm

Sometimes on the zen path you can make fascinating discoveries. In this case it was an occupation called koppedraaijer, spelled variously throughout history.
The copper spinner. His name was Johannes Kopperwijk. He lived in the copper district (kopper wijk) of Utrecht in the early 1700s. One of my ancestors in the not too distant past. My father wore wooden shoes in Utrecht as a child.

Metal spinning is fascinating...
http://www.youtube.com/watch?v=DGszBVy3cgU

(when he says "bass of a lump" he's really saying "base of a lamp")


Dutch

[Char-Gar]

Thanks guys for all your help. in 68 or so, I took a machine shop course at a local college. We learned basic lay out, measuring, drilling, tapping, milling and lathe work. When it comes to the lathe we learned basic drilling, turning, threading and knurling. We held the work in a four jaw chuck and a live center. I was working on a 16" Southbend. That was a long time ago, but I remember allot and more is coming back. One of our tests was "How to run a lathe." by Southbend. I sitll have that little book and will have to dig it out. I still have the text book that has some charts, etc.

The hours I spent in that course, has been time and money well spent. I have used what I learned over and over again in gun work.

[Bent Ramrod]

Another way to tell if your tool point is on center is to get a piece of thin straight metal strip (I use a piece of bandsaw blade) and put it between the tool point and the piece of round stock you are turning. Gently advance the tool (the machine is off) until the point just presses the steel strip against the stock. If the metal strip is straight up and down, you are on center. If the top is cocked inwards, you're too high and outwards you're too low. Adjust accordingly.

You can use a lot of stuff to lubricate while turning but I get better finishes on steel with either Tap-Free or Cool Tool II.

Happy turning. Owning and knowing how to use a lathe really "empowers" you.

[Char-Gar]

When I took my machine shop course, I was taught to put some Dy-Kem on the round stock in the chuck and advance the tool until it was touching (lathe off of course), then run the apron down the bed an inch or so, rotate the work so you can get a good eyeball on it and see if the scratch line was in the center of the stock. Probably not all that precise, but it seem to work for all of us.

We used the same method to center the work in a four jaw chuck. We kept loosening and tightening opposing jaws until the scratch line was even all the way around. For real precise work of course, a dial indicator was the thing. "But for general turning of metal, this seemed to work as well.

[Buckshot]

..............Getcha some good basic lathe books and read, then try some stuff just to make some chips.

http://www.fototime.com/850688703938AEA/standard.jpghttp://www.fototime.com/F62C8E623A0E906/standard.jpg

One of the very first things I made on my lathe was this bolt handle. Not a very good pic, it was the old camara 4 years ago :-) One of the other dispatchers at work had a Winchester semi auto 22 rifle and brought in the broken bolt knob wanting to know if I could duplicate it. Since it was broken in half I also asked for the bolt to make sure some other feature wasn't missing.

http://www.fototime.com/7225E305F08A1BF/standard.jpg

I even tried to duplicate the concentric circles. Not exactly like the original, but who cares? The thing worked!

.................Buckshot

[sharpshooter3040]

OK, I now have a working lathe. It whirs, hums and makes assorted lathe noses. I don't know what it is supposed to sound like, but I don't hear anything that makes me think..bad bearings or oh crap..so I guess I am good for now. Now begins the dumb newbie questions.

1. What is the best speed for general turning, of steel? How about drilling and boring?

2. Tell me about these dumb back gears. They spin just fine, but when I lock them into the other gears in the headstock, nothing will move. I am certain there is a simple answer, but I don't know it.


As always, thanks for any help you can give.

Look at your back gears, one set will have a locking pin in them, thats why nothing will move. remove the pin when you engage the back gears.

Doug

[Big Dave]

Many years ago Ford Motor Co. put out a text book on machine shop training. Might be able to find one in old book places either on line or local

[nametrux]

Here you go. My fav. web site. DL here free as an e-book. Can anything be cheaper? Keep on your comp. and read and print out the info you need.

http://forumw.ca/search.php?mode=results

You may have to reg. but it is free on Forumw.ca some of the DL sites may req. you to reg. but others don't. Hope this helps. Any questions PM me

[82nd airborne]

there is a simple formula for determining rpm. it is "4 x cs/ d"

cs= cutting speed whitch can be found by googleing "cutting speed" and the metal in question.
d= diameter of metal being turned.
when you get a feel for it youll find some speeds work better than the answer from the formula. and roughing and finishing speeds vary, but its a good starting point.

[docone31]

I liked that video!! I used to be a spinner of copper and pewter years ago.
Way cool.
I thought it was a dead art.

[deltaenterprizes]

Sounds like experience speaking to me. :-D:-D:-D


Edd

Where I worked one guy would go high spindle speed, crossfeed on auto feed on the slowest feed rate possible and plenty coolant. He was using a carbide insert parting tool that made the chips bend to be narrower than the groove created by the tool. Those chips were flying out of there like he was taking a roughing cut! I used the tool a couple of times and did it but it was an adrenelin rush waiting for things to jam but it never did!
"How to Run a Lathe" reprints of the one by Southbend is low in cost and very basic for a beginner.

[82nd airborne]

4 times the cutting speed (found in machinists pocket book) divided by the diameter of the part

[PatMarlin]

Charles, I have a manual for your lathe in pdf. What model is yours?

I have an old logan like yours, and the manuals on operation section are all the same.

Speed and feed is one thing on these manual lathes with hand ground HSS tools, but a whole other story on the CNC. I'm working on fine tuning speeds now. I've been using what worked on my manual machines and I'm finding it's to slow for carbide tools on my CNC.

I need to find some good info on speeds and feeds with carbide bits.

[mroliver77]

archive.org is our friend. Lots of text on lathe stuff.
http://www.archive.org/search.php?query=lathe%20AND%20mediatype%3Atexts
Jay

[ClintonJ]

Feeds and Speeds!
Here's a good place to start: http://www.google.com/search?q=feeds+and+speeds&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Feeds and speeds... this describes how fast the part or the cutter is moving and how fast you feed the cutter into the material you are machining... there are thousands of sites waiting to answer your questions!
Here's one that just might be a direct application of what you are looking for!
http://machine-tools.netfirms.com/16_Calculating%20SpeedFeed_Turning.htm

~CJ

[Big Dave]

cutting speeds in surface feet per minute are usually listed for high speed steel tooling. Speed for carbide tooling are from three to seven times faster. Generally with steel tools if you are making blue chips you are about to burn the tool edge off. With carbide if you are not making blue chips you need to go faster or you will chip the tool edge from pressure.

[PatMarlin]

WOW! Never knew about that archive. That is awesome.

One thing I've found calling tech support on speed and feed was no help. I don't think they had actually ran a lathe. Way off the mark.

Also at their suggestiong of a bit (USA)- which I purchased, I ran every combination possible and still was not happy with it.

Just for giggles I tried a (China) bit copy, and it worked very well. Same nose radius and all. Go figure.

[Dutchman]

Great bunch of machine shop videos that are public accessible.

http://techtv.mit.edu/collections/ehs-videos/videos/127-machine-shop-4


Dutch

[scrapcan]

Dutch,

Thanks for positing that link. I had ment to get it up here also. Their is good info in those videos. Especially for those like me who are noew to machine tools.

[JIMinPHX]

How to run a lathe @ brownells for $7.95
# 100-001-043
Lindsay publications reprint of South Bend.
I can run a lathe but I dont know how to post a link

http://www.brownells.com/.aspx/pid=18158/Product/HOW_TO_RUN_A_LATHE

That's a great book. It had been out of print for years. I'm glad to see that it's available again.