Advice on metal lathe

[Mace Canute]

Not true. In fact, I know of several hobbyists that have B'ports or Tree's or Wells Index mills. The guy down the road has a Monarch 10EE in his garage for the sole reason of making parts for his hobby, restoring stean threshers. Certainly not a business for profit.

A machine tool, any machine tool, is only as accurate as the mass it presents against deflection by a cutting tool. That applies universally and you, if you are experienced in the trade should know that. Light weight machines are also light weight in accuracy.

Finally, a base Bridgeport weighs about 1300 pounds.

Very true. I have a BP clone for a mill and it's not any too large, even with a 9" by 49" table and 18" of headroom between the spindle and table. My main lathe is an old South Bend model A with a 9" swing and a four foot bed. I have one in storage with a four and a half foot bed and that would have been nice to have a couple of times but mostly not needed. Even thought the swing is 9 inches, it seems 3 inches is about the maximum practical diameter for workpieces. I would love to have a lathe with a larger swing. You can always do small work on a big lathe/mill but you can't do large work on a small lathe/mill.

 

[5030]

I'm rather new at this game but just purchased a hobby lathe of my own and am looking forward to working with it. Really, it is hard to pidgeon-hole what a hobby lathe is or should be. For me it was something I could make a tractor part (smallish) on if I wanted to although not the primary use. For the well-heeled boss of my machinist friend (and tutor) it is a 5-axis CNC machine (yes, hobby-only use)! It didn't take me long to figure out weight counts for a lot with respect to tractors - maybe even more than HP. The same for machine tools. Interestingly the motors are smallish.

I think one needs to look at what is out there in relative terms: if you do not "need" a full Bridgeport but can acquire one for the same price as a HF mill/drill then why not? I found a clean, used 13" SB in my local Craig's list with some decent tooling: Buck chuck, Aloris tool post, half dozen holders and a set of Hardinge 5C collets. The only less expensive lathe Grizzly even offers is this one:

G8688 7" x 12" Mini Metal Lathe

I can't see any reason to buy it over the SB.

The old used SB has many advantages and some disadvantages. In the disadvantage department, it may have swayback ways from use and it may not be as pretty as the Grizzly but beauty is only skin deep. It may have headstock bearing issues (lots of old SB's do, as I mentioned earlier).

On the advantage side, it's American made (South Bend, Indiana), it's actually made from close grained and stress relieved (aged) grey iron and while it don't have flame hardened ways it's still light years better (and more stable) than the chi-com counterpart. It's all SAE which means that if you need a bolt or nut replacement, the local hardware has one, the feed dials are graduated in SAE decimal graduations, not mm and it has mass. All important for repeatability. Finally, you dan still replicate needed parts on the machine the parts will go on, in other words the lathe can make parts for itself and Flea-Bay is rank with take off parts and assemblies for older SB lathes.

 

[5030]

Very true. I have a BP clone for a mill and it's not any too large, even with a 9" by 49" table and 18" of headroom between the spindle and table. My main lathe is an old South Bend model A with a 9" swing and a four foot bed. I have one in storage with a four and a half foot bed and that would have been nice to have a couple of times but mostly not needed. Even thought the swing is 9 inches, it seems 3 inches is about the maximum practical diameter for workpieces. I would love to have a lathe with a larger swing. You can always do small work on a big lathe/mill but you can't do large work on a small lathe/mill.

I can't see any reason for even considering a benchtop small scale machine because of the inherent limitations on bed length and more importantly, swing, unless you are a watchmaker or never envision turning anything larger than a pop can in diameter.

I regularly swing brake drums and brake rotors through the gap on my Dashin and resurface them. I like to take the wear-in-lip from the outer edge on rotors and the inner ridge on drums off to facilitate easier reinstallation over new shoes or pads. Takes a minute and saves the cost of replacement rotors or drums.

Not to say a small machine don't have advantages. They are easier to use and capable of tighter, close in work, but the larger machine is also capable, it just takes more patience...and skill.

 

[ultrarunner]

I can't see any reason for even considering a benchtop small scale machine because of the inherent limitations on bed length and more importantly, swing, unless you are a watchmaker or never envision turning anything larger than a pop can in diameter.

I regularly swing brake drums and brake rotors through the gap on my Dashin and resurface them. I like to take the wear-in-lip from the outer edge on rotors and the inner ridge on drums off to facilitate easier reinstallation over new shoes or pads. Takes a minute and saves the cost of replacement rotors or drums.

Not to say a small machine don't have advantages. They are easier to use and capable of tighter, close in work, but the larger machine is also capable, it just takes more patience...and skill.

Due to space constraints... my ideal lathe is something like a 13" Regal Leblond

Since I don't have one, my 10" South Bend does 95% of what I need... at one time, I was actually making and selling through the old car club water pump shafts made of Monel...

Like everyone has said... a small lathe can do a lot... it just may take longer...

 

[Mock1]

My two cents. Depends on what you need it for. Three phase power and big motors will cost a bit. If you can offset costs to a customer, that is a good thing. If you have to eat it up, not so good. I have worked on lathes that will swing 26 feet by 40 feet. Used a one inch impact to get the jaws close. Buy the one that fits your needs. And if occasional use is what you need, buy accordingly.

 

[troutsqueezer]

Geez....I hardly know where to begin.

Quote from the OP's opening question: Is a hobby lathe suitable for turning items under a 4-5" in diameter with any accuracy?

The answer is a resounding "yes"! The statements about lightweight machines not being that accurate are completely false and misleading. Both Sherline and Taig make very small lathes and mills and many machinists use them to make extremely accurate parts. Here's just one website to illustrate this. ModelEngines.info

I'm sure for some, "hobby" can mean full size machines. But how many of you have ever lifted a 10" 120 lb rotary table up onto a Bridgeport to make that specialized little 3 inch round part? If you don't mind making weightlifting part of your hobby then have at it. How about an appropriately sized vise for that large table? Expensive and heavy. Hey, you say, you can always put a smaller RT or vise on the table but we're talking full size production quality stuff now, remember? Get the tools that fit the machine.

The cost of the tooling that goes with the lathe or mill no matter which size you buy will exceed the cost of the machine itself, by far. Best to keep that in mind.

Someone mentioned why not get a Bridgeport. There are many reasons not to. Not the least of which is you need a forklift to move it anywhere and it better be on a concrete floor. Affordable, used Bridgeports are often well used (read OLD) and in need of reconditioning, not something for someone wishing to start a hobby making small parts. Do you need 240V for it? Or a phase converter? Count me out, and most other hobby machinists as well.

This is like asking for advice on which tractor to get when you only have one acre. There's always someone out there who will advise you to buy the Case tractor because bigger is always better. Not.

 

[ultrarunner]

I moved my J head Bridgeport with a 4 hour rental truck with a lift gate and then rolled it on 1/2" pipe in the garage...

I took an old 1 hp 3-phase motor to use as my phase convertor and more then 20 years without a problem... forward, reverse, start and stop...

Mine was not new... however the ways were as new. Almost zero machining time... it was used to demo NC milling with a pencil in the chuck.

 

[5030]

Geez....I hardly know where to begin.

Quote from the OP's opening question: Is a hobby lathe suitable for turning items under a 4-5" in diameter with any accuracy?

The answer is a resounding "yes"! The statements about lightweight machines not being that accurate are completely false and misleading. Both Sherline and Taig make very small lathes and mills and many machinists use them to make extremely accurate parts. Here's just one website to illustrate this. ModelEngines.info

That's a fair statement to a point and that point is the little machines also take little cuts. You can't take any appreciable cut because the machines become 'flexible' from delflection. Little = little cuts. Most home machinists have the need and regularly hog even if they aren't familiar with the term....

I'm sure for some, "hobby" can mean full size machines. But how many of you have ever lifted a 10" 120 lb rotary table up onto a Bridgeport to make that specialized little 3 inch round part? If you don't mind making weightlifting part of your hobby then have at it. How about an appropriately sized vise for that large table? Expensive and heavy. Hey, you say, you can always put a smaller RT or vise on the table but we're talking full size production quality stuff now, remember? Get the tools that fit the machine.

One does not need to purchas a large rotary table or indexing head or milling machine vise. I have a Troyke that weighs way more than 120 pounds. I also have a small one that weighs about 20 pounds. It's economy of scale and what you use the tooling for that determines the overall size. Both tables are happy on the vertical mill....

The cost of the tooling that goes with the lathe or mill no matter which size you buy will exceed the cost of the machine itself, by far. Best to keep that in mind.

Someone mentioned why not get a Bridgeport. There are many reasons not to. Not the least of which is you need a forklift to move it anywhere and it better be on a concrete floor. Affordable, used Bridgeports are often well used (read OLD) and in need of reconditioning, not something for someone wishing to start a hobby making small parts. Do you need 240V for it? Or a phase converter? Count me out, and most other hobby machinists as well.

My comment is that most B'ports that are used will need ball screws but replacing intrinsic parts gives the owner a 'feel' for what's inside and how it works. As far as utility (electric) bills go, it's cheaper to spin a 240 volt motor over a comparable one thats 110 and 3 phase (if you have it) is even cheaper per KWH than single phase and a capacitor banked static convertor that will run a 3/220 B'Port costs less than 100 bucks new and is the size of a box of cereal.

This is like asking for advice on which tractor to get when you only have one acre. There's always someone out there who will advise you to buy the Case tractor because bigger is always better. Not.

Bridgeports and medium sized lathes are easily moved. A B'Port comes apart, the upper ram/head is easily removed from the base (4 capscrews). I routinely move them with a Harbor Fright engine cheerypicker, myself, no help. Lathes can be seperated from bases, headstocks can be removed, I do it all the time, it's not mysterious. Any lathe can be repowered from 3/220 to 1/220 or 1/110. NEMA framed motors are designed for interchangeability.

I'm very familiar with the 'little machines'. However, a little machine has very little capability except for producing little parts. In the case of Sherline, I don't consider extruded aluminum parts to be load bearing except with small cuts....and the home machinist will always, at some point, attempt to take the largest possible cut. It's human nature....Lets see what this machine will do......

That in itself can be the end of a light weight table top machine. They aren't built for that abuse...... Not that a B'port isn't just a glorified drill press with power downfeed......:laughing:

Tractors are different. With machine tools, always buy the largest (in capacity) that you can afford and are capable of setting. I would never set any machine on anything but a concrete floor. It's ludicrious to think that any machine (except a tabletop machine) will produce repeatable accuracy mounted on a flexible surface...

Tractors, on the other hand, owners seem to buy more than they need. I look at that as one upmanship, like my 4x4 is bigger, sits higher and has louder exhaust but the only thing it gets used for is trips to WalMart for groceries......:laughing:

Personally and candidly speaking, I don't give a hoot what anyone buys, I'm not paying for their folly. That applies to tractors as well.

My advice is based solely on my experience not only as a owner and commercial manufacturer but as a user. I started out with the premise of a hobby shop, but I still started out buying the largest capacity machines I could reasonably handle.

Would I recommend a 3 axis CNC vertical machining center to a home hobbyist? Of course not, not unless their wallet could handle it. My Haas was well north of 45 grand. If you have the wallet however, CNC controlled machines are the way to go. Besides, with conversational programming, a CNC machine can be run just like a manual operated mill, you just don't crank the handwheels......:thumbsup:

 

[troutsqueezer]

Bridgeports and medium sized lathes are easily moved. A B'Port comes apart, the upper ram/head is easily removed from the base (4 capscrews). I routinely move them with a Harbor Fright engine cheerypicker, myself, no help. Lathes can be seperated from bases, headstocks can be removed, I do it all the time, it's not mysterious. Any lathe can be repowered from 3/220 to 1/220 or 1/110. NEMA framed motors are designed for interchangeability.

I'm very familiar with the 'little machines'. However, a little machine has very little capability except for producing little parts. In the case of Sherline, I don't consider extruded aluminum parts to be load bearing except with small cuts....and the home machinist will always, at some point, attempt to take the largest possible cut. It's human nature....Lets see what this machine will do......

That in itself can be the end of a light weight table top machine. They aren't built for that abuse...... Not that a B'port isn't just a glorified drill press with power downfeed......:laughing:

Tractors are different. With machine tools, always buy the largest (in capacity) that you can afford and are capable of setting. I would never set any machine on anything but a concrete floor. It's ludicrious to think that any machine (except a tabletop machine) will produce repeatable accuracy mounted on a flexible surface...

Tractors, on the other hand, owners seem to buy more than they need. I look at that as one upmanship, like my 4x4 is bigger, sits higher and has louder exhaust but the only thing it gets used for is trips to WalMart for groceries......:laughing:

Personally and candidly speaking, I don't give a hoot what anyone buys, I'm not paying for their folly. That applies to tractors as well.

My advice is based solely on my experience not only as a owner and commercial manufacturer but as a user. I started out with the premise of a hobby shop, but I still started out buying the largest capacity machines I could reasonably handle.

Would I recommend a 3 axis CNC vertical machining center to a home hobbyist? Of course not, not unless their wallet could handle it. My Haas was well north of 45 grand. If you have the wallet however, CNC controlled machines are the way to go. Besides, with conversational programming, a CNC machine can be run just like a manual operated mill, you just don't crank the handwheels......:thumbsup:

If you are a hobby machinist, you have the time to take those smaller cuts. Add to that, the parts you are likely making are small in and of themselves. Again, we are not talking production here, where time is of the essence.

I would say, Sir, that the rest of your post is an endorsement of the points I was trying to make. Now, on to more important things.....

 

[mwb]

I've got a bench top lathe, a Myford ML-7 I think it is. Problem is I learned on larger engine lathes and get frustrated by the power, size and hole through the headstock on the Myford. Someday I'll get something a bit bigger to tackle my farm sized projects.

:thumbsup: I have one of those too! Even have the owners manual for it. Nice little lathe but, like you, I want a bigger one. Some day, bigger lathe and a mill