Posted: 7/27/2009 12:42:16 PM EDT
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I have acquired (and attempted to use with some ROUGH output) an old 1940's atlas 6x18" lathe, however I do not really know what I'm doing. If anyone in the Central TX area had some time to come educate me a bit, I'd be happy to bribe with cold refreshment or food of your choice. Specifically, how should it be correctly set up, tools to acquire, basic education stuff.
I have the running lathe, 3jaw chuck, fixed center and 1/2" chuck for the tail, a few cheap cutting tools, etc. Here's the best info I've found on what I have: http://www.lathes.co.uk/atlas6inch/ I'm in N. Austin. Jess |
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If I were closer I'd be over asap. What, specifically, do you need help with?
First thing to do is make sure it's level, and to do it properly you need a level that is graduated and accurate to .0005" in 12". Precision levels aren't cheap, but they're worth it. After leveling, check the slop in the compound rest/cross slide/saddle. Adjust the gibs as required to obtain a snug fit over the entire range of travel. Next comes test cuts to find out if there is any taper, and adjusting the tailstock so it's on center. Get a good magnetic base, a travel/plunger type indicator and a good dial test indicator...also, a four jaw chuck. You might want a set of test buttons too. If it has a QC tool post, buy several "extra" tool holder blocks. Send me an IM if you need help finding stuff. 
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Mostly just setup help. Right now I have no permanent place to put it, so leveling it precisely is not really possible. Adjusting all of the components for slop and centering the tailstock sound like what I need.
Why 4jaw over 3 jaw? test buttons? magnetic base for what? J |
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four jaw chucks are easier to center parts accurately. the best chuck i ever used was a manual four jaw. 3 jaw chucks are ok, but are harder to zero in parts. either gotta shim it or whack it with a hammer to center.
magnetic base for dial indicators. http://www.noga.com/nogaProducts.php?prdID=DG6150 personally i prefer the noga with the single knob adjust. harbor freight sells some cheap magnetic bases with the indicator, i cant say about the quality of the indicator but the base works like a magnet should. |
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Mostly just setup help. Right now I have no permanent place to put it, so leveling it precisely is not really possible. Adjusting all of the components for slop and centering the tailstock sound like what I need. Why 4jaw over 3 jaw? test buttons? magnetic base for what? J If leveling it isn't possible, accuracy is going to suck. You may also wind up with a warped bed depending on how long it sits and how far out of level it is. Three jaw chucks are quick to use, but if you have to remove the part, there isn't any repeatability with it. Four jaw chucks allow you to precisely dial the part in via the use of an indicator on a magnetic base. The four jaw is also pretty much the only way to work with anything other than round stock. If I were going to be limited to one chuck, it would be a four jaw. The test buttons make it a little easier to get the tailstock lined up. They're precisely sized. You install one in the tailstock and one in the chuck/spindle. You then move the tailstock up until the two buttons meet and measure over them. If the measurement in any direction comes out larger than the diameter of the buttons, you know it's off and how much it needs to be moved. magnetic base dial test indicator Plunger type indicator precision level I can't find a set of test buttons right now and can't remember the last place I saw them advertised. I'll have to do some more searching to find them. You can probably find some of this stuff on ebay a little cheaper, but don't skimp on the measuring instruments. |
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I pulled mine out of a junk pile at my uncle's shop.
It has the lathe, motor and pulley set. I bolted it all to a few 2x4's to see if it worked. I've turned down some stuff of mild steel, plastic and recently 316l stainless (what a bitch that stuff is). It's been fun to tinker with, but there's some things that I think are not correct and someone with experience could ID and resolve fairly quickly. |
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I pulled mine out of a junk pile at my uncle's shop. It has the lathe, motor and pulley set. I bolted it all to a few 2x4's to see if it worked. I've turned down some stuff of mild steel, plastic and recently 316l stainless (what a bitch that stuff is). It's been fun to tinker with, but there's some things that I think are not correct and someone with experience could ID and resolve fairly quickly. 316 isn't hard to turn. Low rpm and heavy cut/medium to high feed. What kind of cutting tools are you using? ETA: I missed this earlier, but that lathe needs to be bolted to a very sturdy bench, or heavy duty metal stand. Whatever it's mounted on should make the machine more rigid. I also forgot to ask if you got all the change gears for it. If you didn't, you should be able to find a set(or individual gears) on ebay, and I think there was a link to a supplier on the page you linked to. |
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I recommend you get the same two books I did: the Student Machinist Guide. There is a LOT of good information in them and they go into detail about just about everything you will need to know. most machinist supply stores can get the books or I am sure you can find them online. That is my recommendation about where to start.
Oh, yes - my first lathe ((8 years ago) was a World War II era Shelton Army Lathe. Lots of fun. |
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316 isn't hard to turn. Low rpm and heavy cut/medium to high feed. What kind of cutting tools are you using? I had the spindle set to the slowest RPM, but because I didn't have a live center, or good cutting tools, I work hardened it quite often. Ended up breaking one of the cutting tools trying to apply enough pressure :) |
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316 isn't hard to turn. Low rpm and heavy cut/medium to high feed. What kind of cutting tools are you using? I had the spindle set to the slowest RPM, but because I didn't have a live center, or good cutting tools, I work hardened it quite often. Ended up breaking one of the cutting tools trying to apply enough pressure :) How long of a piece were you trying to turn? Generally if your workpiece stickout is under 2-3x the diameter, a center isn't necessary. HSS tools, brazed carbide, or inserted carbide? If HSS, cobalt or brazed carbide, you'll need to grind the proper angles for relief and whatnot. I don't recall off hand what the recommended angles are...I just grind them until they look right.  Brazed carbide will require a diamond wheel on a somewhat specialized type of bench grinder. For anything other than aluminum, you want a slight radius on the tip of the cutting edge. If you want a stronger tool, grind a larger radius. Also, if HSS, you have to keep a steady drip of cutting oil on it at the least. IMO, sulfurized cutting oil works better than anything else on stainless.
ETA: I just saw the size of the lathe. I recommend using HSS(high speed steel) or cobalt alloy steel tools only. The small machines aren't rigid enough IMO for the use of carbide, and will put excess wear on the machine due to the higher cutting pressures required. Make sure the tool is set on center. The quick ways to do this are easy. One is by using a steel rule between the cutter and the part. Apply just enough pressure with the tool to hold the steel rule in place. If the top end leans away from you, the tool is over center. If it leans toward you, it's below center. The other way is by eyeballing it on the point of the live/dead center. FYI, you need some good grease/anti seize if you're using a dead center. You can get a decent live center pretty cheap. Any idea what the tailstock taper is? ETA: It's probably a number one morse taper. Try looking for one at littlemachineshop.com. What type of tool post are you using? Is it the old style lantern/rocker type or a four way...or a quick change? HA! I just looked at the link you posted and I have a Craftsman Model 109.21280( I think), and now finally know how to operate the back gear on the damn thing!! BTW, if you aren't aware of it, engaging the back gear reduces the speed significantly. I don't know what the lowest speed possible will be though. BTW, all of the tool posts I've seen in the pictures at that link are the old style lantern/rocker type. Better suited to the smaller machines than other types IMO. I really need to spend $140 and get my South Bend wired up. 
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How long of a piece were you trying to turn? Generally if your workpiece stickout is under 2-3x the diameter, a center isn't necessary. –– Way longer, prolly 5x length HSS tools, brazed carbide, or inserted carbide? If HSS, cobalt or brazed carbide, you'll need to grind the proper angles for relief and whatnot. I don't recall off hand what the recommended angles are...I just grind them until they look right. Brazed carbide will require a diamond wheel on a somewhat specialized type of bench grinder. For anything other than aluminum, you want a slight radius on the tip of the cutting edge. If you want a stronger tool, grind a larger radius. Also, if HSS, you have to keep a steady drip of cutting oil on it at the least. IMO, sulfurized cutting oil works better than anything else on stainless.
ETA: I just saw the size of the lathe. I recommend using HSS(high speed steel) or cobalt alloy steel tools only. The small machines aren't rigid enough IMO for the use of carbide, and will put excess wear on the machine due to the higher cutting pressures required. –– Harbor freight brazed carbide tools. They seemed to cut pretty good when I could get enough force on it. I burned up a couple HSS cuttoff tools though. I tried regular 30wt motor oil as it's what I had at hand. Make sure the tool is set on center. The quick ways to do this are easy. One is by using a steel rule between the cutter and the part. Apply just enough pressure with the tool to hold the steel rule in place. If the top end leans away from you, the tool is over center. If it leans toward you, it's below center. The other way is by eyeballing it on the point of the live/dead center. –– Didn't even think to use the live center to level the cutting tool. FYI, you need some good grease/anti seize if you're using a dead center. You can get a decent live center pretty cheap. Any idea what the tailstock taper is? ETA: It's probably a number one morse taper. Try looking for one at littlemachineshop.com. –– yeah it's MT1. I found a jacob chuck for it for $20 on ebay. need a key. What type of tool post are you using? Is it the old style lantern/rocker type or a four way...or a quick change? –– lantern style, thanks for the description that let me know what to call it. HA! I just looked at the link you posted and I have a Craftsman Model 109.21280( I think), and now finally know how to operate the back gear on the damn thing!! BTW, if you aren't aware of it, engaging the back gear reduces the speed significantly. I don't know what the lowest speed possible will be though. BTW, all of the tool posts I've seen in the pictures at that link are the old style lantern/rocker type. Better suited to the smaller machines than other types IMO. –– if I engage the back gear (also now know what to call that), it locks the lathe up tight. Something else needs to be disengaged? I really need to spend $140 and get my South Bend wired up. |
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–– Way longer, prolly 5x length
Diameter? If it was small stuff, 5x stickout is getting too long for standard cutting tools without a steady rest or follow rest. I don't know if either of those items were made for the atlas lathes. –– Harbor freight brazed carbide tools. They seemed to cut pretty good when I could get enough force on it. I burned up a couple HSS cuttoff tools though. I tried regular 30wt motor oil as it's what I had at hand.
It shouldn't take a whole lot of pressure to get the tool cutting, unless it's ground wrong, not on center, or the rake of the tool is wrong. Cutoff tools are particularly picky about how they will or won't run. They need to be perfectly on center AND perfectly square to the work(and have good oil)....otherwise they burn up or break pretty quick. Also, you have to keep pecking away at it. Roll in maybe .040" to .060" and then back out slightly to break the chip. The cutoff tools I have for my machine are pretty narrow and won't take much load. The less tool stickout you have, the better. Ideally 2x or less the height of the blade. IOW, you want 2" or less stickout if the blade is 1" tall. Brazed carbide is generally sold in two grades, C2 and C5. You might find some others though. Here is a link on the difference since it saves me some typing. Explains the difference Also, that's the forum for Home Shop Machinist magazine. There are some VERY knowledgeable professional machinists there, along with a bunch of inventive garage machinists. 
–– Didn't even think to use the live center to level the cutting tool.
Lots of folks don't. With the lantern style tool post, it's probably easier to use the steel rule method though. –– lantern style, thanks for the description that let me know what to call it.
–– yeah it's MT1. I found a jacob chuck for it for $20 on ebay. need a key.
How large/what model is the chuck? This page has chuck keys by chuck model number for Jacobs chucks. –– if I engage the back gear (also now know what to call that), it locks the lathe up tight. Something else needs to be disengaged?
Yes. The back gear serves a dual purpose in that you can lock the spindle to install/uninstall the chuck. Swap over to the Atlas MK 2 page and have a look. I'm going to guess that the older one you have will work the same, but I didn't read the MK1 page, so I'm not for sure. |
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Here is a type of wheel you can use on a regular bench grinder to sharpen the brazed carbide tools. I'm not overly fond of them because they break down very quickly, but they do work. Enco has three grits, the linked one is a 60 and will cut pretty fast.
This is the style of grinder that most shops will use for brazed carbide, since it has adjustable tool rests and allows you to properly set angles. I believe harbor freight carries a similar grinder. With a different set of wheels, you can also use it on HSS or cobalt tools. ETA: this is a much less expensive version of the above. M2 Cobalt rectangular bits here 10% Cobalt square bits here There are some 8% and 5% grades at the bottom of the page. Dunno what size your cutoff tool holder is, but here are some 1/2" tall, .062" wide carbide tipped parting tools. |
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Mostly just setup help. Right now I have no permanent place to put it, so leveling it precisely is not really possible. Adjusting all of the components for slop and centering the tailstock sound like what I need. I can't find a set of test buttons right now and can't remember the last place I saw them advertised. I'll have to do some more searching to find them. You can probably find some of this stuff on ebay a little cheaper, but don't skimp on the measuring instruments. I got a set of test buttons from Brownells. I think that they were about fifty bucks. Also, I've had good luck with Enco and Penn Tool for supplies. |
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Mostly just setup help. Right now I have no permanent place to put it, so leveling it precisely is not really possible. Adjusting all of the components for slop and centering the tailstock sound like what I need. I can't find a set of test buttons right now and can't remember the last place I saw them advertised. I'll have to do some more searching to find them. You can probably find some of this stuff on ebay a little cheaper, but don't skimp on the measuring instruments. I got a set of test buttons from Brownells. I think that they were about fifty bucks. Also, I've had good luck with Enco and Penn Tool for supplies. $27 dealers cost from Brownells. http://www.brownells.com/.aspx/pid=694/Product/LATHE_CENTERING_BUTTONS What about something like this: http://www.brownells.com/.aspx/pid=20884/Product/LATHE_CENTERING_BAR |
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Mostly just setup help. Right now I have no permanent place to put it, so leveling it precisely is not really possible. Adjusting all of the components for slop and centering the tailstock sound like what I need. I can't find a set of test buttons right now and can't remember the last place I saw them advertised. I'll have to do some more searching to find them. You can probably find some of this stuff on ebay a little cheaper, but don't skimp on the measuring instruments. I got a set of test buttons from Brownells. I think that they were about fifty bucks. Also, I've had good luck with Enco and Penn Tool for supplies. $27 dealers cost from Brownells. http://www.brownells.com/.aspx/pid=694/Product/LATHE_CENTERING_BUTTONS What about something like this: http://www.brownells.com/.aspx/pid=20884/Product/LATHE_CENTERING_BAR If you don't have a center for the taper in the headstock, that bar won't do you any good. |