The Turning Point
February 6th, 2009Lathe?
The more I look at machine tools, the more confused I get.
I think a mill is a necessity, if I ever expect to think of myself as a man. But I was hoping to avoid buying a metal lathe.
Well, look what I have learned.
You can use a metal lathe on wood. Also, really good used metal lathes sell for very low prices. Finally, you can get a 9 x 20 Chinese job that will do a lot of stuff and teach you a great deal…for $700. Now, I realize you can get a used South Bend for less than that if you watch the ads. BUT, unless what I’ve read is nonsense, it’s a very bad idea to buy a used lathe unless you have some experience using this kind of tool. So this may be an example of one of the rare occasions when buying small, cheap, and Chinese may be a great idea. What do you lose when you resell one of these things? No more than $700. Probably more like $300. For that, you get a course in using a lathe. My cheapness gene is alert and ready to pounce.
I believe it should be possible to make pulleys on a machine this size. The “9” refers to the diameter of the largest possible object you can turn. You can’t really go that high, but you can get close. So 6″ should be no problem. HF sells a metal cabinet, but I have a bunch of two-by-sixes I need to get rid of, and this thing only weighs 300 pounds or so, which means wood is way more than adequate.
Dang, I may do this. The local HF could get it for me, saving me money on shipping. I could learn a little bit about machining, and I could get smart enough to evaluate a real American used lathe, and then I could upgrade for a few hundred bucks. Maybe this is smarter than farting around with mills right off the bat. Right now, there are some really fine machines on Craigslist. It’s too bad I’m not competent to buy one.
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Let’s say I have a spiffy HF 45861 lathe, as well as a pulley that is 6″ wide and 6″ across. Can I use the lathe to drill a hole for an axle, centered correctly in the pulley and going from one side to the other?
February 6th, 2009 at 2:55 PM
Howdy
First time commenter. I would really be interested in seeing how this works out for you. I have had my eye on a mill/lathe combo and wondered about whether or not to get the chiwanese and learn on it or try to get a used one. I will be self training so the quality of chiwanese models will probably exceed my ability to use it. One thing I do know about these things is that the unit purchase is only the first thing, you will have a lifetime of accessories to purchase. Please keep us posted on your success with this.
Thanks
February 6th, 2009 at 3:00 PM
There is a guy on one of the home machinist forums who has done wonderful things with a Harbor Freight 3-in-1. I have heard that the big problem with these machines is the tiny clearance between the mill and the work.
February 6th, 2009 at 4:56 PM
“Let’s say I have a spiffy HF 45861 lathe, as well as a pulley that is 6? wide and 6? across. Can I use the lathe to drill a hole for an axle, centered correctly in the pulley and going from one side to the other?”
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This kind of thing is ridiculously simple with a Lathe (did my Rotary Table setup on a Mill get you to this point?)
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On a lathe, you would just start boring, then stop and measure and then continue enlarging until you’ve reached your chosen diameter.
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Make sure Tool-Rest/Boring Tool can go deep enough. If the pulley we’re talking about is the steel “drum” then you only need to go 1/8″ deep on the end-caps (standard boring tool should work fine). If its solid billet, then you may need to setup a Tool-Rest Chuck and a (5/8″?) Drill-bit to get to 6″ deep.
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Note, you can also bore for 3″ and then flip it over and bore another 3″, but you may end up with a few thousands of an inch “lip” half-way down the bore.
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Either way, you’ll have your pulley and a Lathe. At that point you can also make furniture legs! Well 20″ furniture legs anyway. Okay you can go longer, but then you’d have to segment them with those funny double-ended wood-screws…
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Hmmm…what else can I enable? Have you looked at Anodizing? If you make your pulleys out of aluminum, you could do all sortsa fun colors:
http://www.focuser.com/atm/anodize/anodize.html
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Well, I’ve done my part…now to take me son off to see “Hotel for dogs” and catch up on some sleep.
February 6th, 2009 at 5:26 PM
Update: I looked at the HF 45861 and noticed it comes with a 4″ Chuck (meaning the largest piece of stock you can mount in it is limited to 4″).
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You’ll probably have to buy a larger chuck to turn your 6″ pulleys…sorry.
February 6th, 2009 at 5:57 PM
I don’t recommend the 9×20’s. They rely on a 6mm urethane belt that is almost impossible to keep aligned, costs about $10, is difficult to find and even more difficult to replace. Mine needed replacing approximately every three or four hours. The sellers have little to no help available for repairs or adjustments which will be needed. The owener’s manuals are written in a rare and arcane dialect of Chinglish. The manual with my ENCO 9×20 was hand typewritten and stuck together with a paperclip. All drawings seemed to have been copied on a first generation Xerox.
As to turning or drilling a 6×6 pulley in a 9×20 lathe: highly unlikely. Insufficient power or clearance for workpiece holding and tooling. Other bad things about the Chicom 9×20 are the teensy little headstock bore, and extremely awkward tool holder system.
Keep looking until you find an Atlas or South Bend 10×36 lathe. Sears and Montgomery Ward sold tens of thousands of these as home workshop tools and most remain nearly unused, you just have to find the one with your name on it. Even more common are the Atlas and SB 9×36’s. All are well made useful tools, using the American Rocker tool holders.
The main trouble with 3in1’s is that they are so springy it is near impossible to cut to a dimension the tools are supported very badly. I’ll wager the home machinist is cutting aluminum and brass making very small parts. Another thing is if you need to use the lathe, you have to tear down any milling setup. If you need to mill, you’ll be tearing down the lathe setup, if you need to drill, well, you get the drift. It’s a lot like a ShopSmith for metal. It’ll do everything, just poorly and inefficiently.
Except maybe being an anchor for an old rotten boat that leaks.
There are some really good books out. Google “How to Run a Lathe”.
Gerry N.
February 6th, 2009 at 6:01 PM
Used lathes are all over the place. The problem is, I can’t tell a good one from a bad one. So it looks like Harbor Freight for me.
February 6th, 2009 at 8:28 PM
I don’t know – intervention or buy a big metal building. Something has to give.
February 7th, 2009 at 12:26 AM
Steve, you need to go look at some lathes, you’ll soon learn to tell the worn, tired ones from those with only minor wear. It really isn’t rocket science. Wear patterns are obvious as is poor maintainance. Learn to trust yourself. The chaiwanese stuff starts out badly manufactured and deteriorates quickly.
My ENCO 9×20 (Identical to the HF except for color) had a funny little divot in the paint on the lower part of the bed casting. I dug at it with a screwdriver and found a large bubble in the casting that the factory had filled with mud and painted over. That’s the kind of QC you’ll be dealing with.
Good luck.
Gerry N.
February 7th, 2009 at 9:35 AM
“Update: I looked at the HF 45861 and noticed it comes with a 4? Chuck (meaning the largest piece of stock you can mount in it is limited to 4?).”
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Unless the chuck jaws go further out from the hub than the 4″ diameter (which they most probably will). Maybe I should drink coffee in the afternoon?
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Probably best to go and look at one at HF to see how far the chuck jaws will go.
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I did find this info on the 9X20’s:
http://www.mini-lathe.com/Mini_lathe/Versions/Versions_9x20.htm
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Now to go get some coffee before I even get near the Mill this morning!
February 7th, 2009 at 11:45 AM
Steve,
Gerry is right, you need to look at a few lathes. Also, go back and re-read that site that I linked earlier: http://www.mermac.com/advicenew.html
My buddy did as you are contemplating, but he went with a 12 or 13″ lathe from Enco. Of course, it nearly ruined a $3000.00 bill, but it’s all-new. Bad thing is, we still have to fit a 3-phase motor w/VFD so it’ll run slow enough for easy threading.
I’d recommend that you at least look at that lathe on Craig’s List. My first lathe came from newspaper ad, sold for “best offer”. To make a long story short, I ended up paying only $100.00 (in 1966) for that 1933 Atlas lathe. It served me well for at least 12 years.
February 7th, 2009 at 12:04 PM
Og says to buy it and see what happens.
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Not sure how you get an 800-pound lathe into a U-Haul truck. Even with a liftgate, I have to be able to get it onto the gate and into and out of the truck.
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I think I have finally found a challenge the Explorer cannot deal with. Perhaps if I remove the roof with a plasma cutter…
February 7th, 2009 at 1:56 PM
New Import vs. Used American iron, a timely thread:
http://bbs.homeshopmachinist.net/showthread.php?t=33165
February 7th, 2009 at 2:10 PM
If that thread is right, the HF 9 x 20 is $560 right now.
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Some guy near Tampa has a South Bend 9″ job for $950, with a bunch of stock and tooling.
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Also a Logan 200 in Port Saint Lucie, for $850.
February 7th, 2009 at 2:52 PM
“Some guy near Tampa has a South Bend 9? job for $950, with a bunch of stock and tooling.”
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Roadtrip?
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Time to make friends with a pickup owner or get yourself one of these for the Explorer:
http://tinyurl.com/27e4m3
http://tinyurl.com/dbbbcq
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Should I be listening for “Runaway Lathe” Reports along I-75? 🙂
February 8th, 2009 at 9:02 PM
Lathes are great and fun to use but the purchase price is about half to three quarters the cost of getting anything useful done on it. For instance, the 6″ belt sander rollers you’re contemplating, if I’m picturing what you’re doing, would take a few things that usually do not come with the lathe: A drill chuck for the tail stock, center (spotting) drill(s), a steady rest big enough for the roller (and a 9″ lathe will not have a 6″ steady rest unless the laws of physics have been repealed), carbide or HSS exterior turning bits, a live center, and either a live bull nose or bull nose adapter for the live center. Some things that would really make it productive but you don’t absolutely have to have are: dial indicator with mag base, a set of inside micrometers, calipers or outside mics, and a green wheel for your bench grinder to sharpen the carbide. The belt sander WILL NOT do this and you really need a green or white wheel for the bench grinder or you’ll get real tired of tearing up parts with dull or out of shape carbide.
If your 4″ chuck has a set of interior grip chuck jaws along with the exterior ones, you should be able to chuck to the inside of a piece of 6″ tubing. Weld your end plates about 3/4 to one inch in from the end of the tube and you can chuck to the inside. Use the bull nose center in the tail stock to hold the other end and face the roller to true it’s OD with the chuck/bullnose axis. Remove very little material at a time to keep from flexing the roll and creating a crown.This is where a steady rest and dial indicator come in handy; indicate the opposite end (from the chuck) of the roller to get it as straight as possible to the chuck using the steady rest and use the drill chuck in the tail stock to spot drill a center hole. Then swap to a regular drill bit the size you need for the bore. Flip the roll over and do the same from the other end. Break the edges with a file and sand the face to ‘purty it up’ and Voila! Roller.
I’d recommend 6″ OD DOM tubing with at least 1/8′ wall so you’ll have some ‘meat’ to work with in the truing operation.
If you need to broach a key slot in your endplates, then that’ll call for an arbor press and a broach set of the proper size. nice stuff to have if you can get it for a good price. Otherwise, drill a hole through the face or the roller right in the center of the thickness of the end plate. Assuming an end plate thickness of 1/4″ drill to within about 1″ of the shaft bore with a #7 drill bit (.201″ -clearance drill for 10-32) and drill the rest ot the way with a #21 (.159″ – tap drill for 10-32) then get a 3/4″ to 1-1/4″ long 10-32 Allen head set screw to go against the shaft and drill a divot in the roller shaft where the setscrew will hit. If you do this, make sure the setscrew has a chamfer on the end so it doesn’t mushroom out and make it impossible to come bake up through the hole. That really screws up a set of Allen wrenches when that happens.
You’ve probably quit reading by now but if you think ahead about 3 steps, it will cut down on the growth rate of your scrap pile. Same as with anything else. I just found this blog yesterday and I’ve looked at a few things you’ve built recently and if you can do that, you’ll be a whiz at a lathe. Just re-building that bandsaw makes you sharper than half the guys I know running lathes for a living. It just requires a little different mindset from woodworking.