Hi All, first post here. I stumbled in to this forum searching lathes and found several threads that either were here or pointed here from other forums (practical machinist for example). So I think I at least found the right place.
I am studying metal lathes as I would like to add one to my collection at some point. That will open up a lot of doors with projects. I got a floor mount drill press last year and that has equally opened a lot of doors - even milling with a cross slide vice (not ideal, and not "precise", but better than nothing in a pinch).
At the moment I don't have any size parts/work to base the sizing of a lathe off of, however most of the parts I can think of are nearly all close to the chuck - within 3" or so in length. I do have some shaft ideas - perhaps out to about 18" (bearing journals). Max shaft diameter might be 2" or under. Of course, threading is going to be a big help. As to what pitches - I don't see anything other than standard pitch threads in my future, but that gets in to the root of my question. Power feed in both major axis (x and y) would be a requirement, as far as I'm concerned. I am not sure how important the ability of tapered power feeding would be, but that, again, gets back to the root of my question.
I like the styes that have gear selections with levers as opposed to change gears (with the exception being switching between standard and metric pitch threading - that I can understand).
Like a lot of the points made in a lot of the threads I've read - the machine doesn't make the machinist. Part of the art of machining is being able to get good results in sub-par conditions. Whether that is less than adequate tooling or excess looseness in machine tolerances, getting to know a machine and the tooling one has to use is the key - and not taking off too much material. Having said that, and understanding that the import market is about all there is in the price range of the usual garage/hobby machinist budget, I can reason looking that direction as opposed to a quality used machine. I'd also rather not chase lucrative "quality" (read that as still operable and not worn out) machines around the country. I would, however, want to check a machine over before bringing home (so ideally picking up in person as opposed to having shipped).
Back to the import options - I realize that there are a lot of die-hard machinists out there that frown on them. However, I am also a realist and have done enough research on machines to know that there are good results to come out of some of the choices out there. My drill press, for example - its from Taiwan and is older than I am. It's not a pretty machine, but again - it isn't the machine that makes the machinist.
Given the 12x36 ballpark size - and the features I've mentioned - are there any options that jump out to you that are worth mentioning in that class?
Are there any features that you would like to have that you don't, or that you have that you are darn glad you have? Are any of those features able to be added after-the-fact (like a DRO, CNC, power feed, etc)? Or is there an option, or options, that a machine needs to be built with from the factory?
What I am trying to figure out is how to not get myself in to the hole of out-growing a machine. The idea of getting a smaller, more basic lathe is certainly there. Then use that as a "starter" lathe and upgrade later. I suppose I'll see what time brings in ideas and options.
I did pass up a big floor mount 3 phase lathe, around a 14x50 or so, back in 2009 as I didn't have a place to put it nor 3 phase power. That is one of those situations that I look back on and just wish things would have been better on my end to make that work.
I have run lathes before in school - even CNC and ProtoTRAK controlled machines. Its been years since I have done any of that, though.
Power is a consideration. I think single phase 220 is probably the most ideal. I realize there are ways to get 3 phase with a home-brew rotary phase converter. That isn't out of the realm of possibilities, but I think that is one more thing that could make for an inconvenience. If going to 3 phase is key to getting in to a category of non-out-grow-able lathes then it might make more sense.
One last point/question:
My understanding is that DC motor drives for variable speed ability (usually seen on smaller lathes - 10x22 or less - as an option) loose torque at lower speeds within each range. Variable frequency drives supposedly offer higher torque. What comments can anyone offer in regards to this? All the lathes I've run have been constant speed 3 phase motors - geared and belt drive, 2hp and up.
On the same torque question/point - how important is gear range/RPM selection? Like some of the Grizzly's have 9 speeds and some have 8 speeds - 70-2000rpm range. Then some Precision Matthews in the same size range have 12 speeds 70-1200rpm or so. My theory is still the same "machine doesn't make the machinist" here - that the limitation in speeds isn't a big deal, but I would like some deeper thought/perspective from those that are using either - low speed count or high speed count, or variable speed drive?
Lots of points, topics, and questions, I know. Thanks for any further insight.
I am studying metal lathes as I would like to add one to my collection at some point. That will open up a lot of doors with projects. I got a floor mount drill press last year and that has equally opened a lot of doors - even milling with a cross slide vice (not ideal, and not "precise", but better than nothing in a pinch).
At the moment I don't have any size parts/work to base the sizing of a lathe off of, however most of the parts I can think of are nearly all close to the chuck - within 3" or so in length. I do have some shaft ideas - perhaps out to about 18" (bearing journals). Max shaft diameter might be 2" or under. Of course, threading is going to be a big help. As to what pitches - I don't see anything other than standard pitch threads in my future, but that gets in to the root of my question. Power feed in both major axis (x and y) would be a requirement, as far as I'm concerned. I am not sure how important the ability of tapered power feeding would be, but that, again, gets back to the root of my question.
I like the styes that have gear selections with levers as opposed to change gears (with the exception being switching between standard and metric pitch threading - that I can understand).
Like a lot of the points made in a lot of the threads I've read - the machine doesn't make the machinist. Part of the art of machining is being able to get good results in sub-par conditions. Whether that is less than adequate tooling or excess looseness in machine tolerances, getting to know a machine and the tooling one has to use is the key - and not taking off too much material. Having said that, and understanding that the import market is about all there is in the price range of the usual garage/hobby machinist budget, I can reason looking that direction as opposed to a quality used machine. I'd also rather not chase lucrative "quality" (read that as still operable and not worn out) machines around the country. I would, however, want to check a machine over before bringing home (so ideally picking up in person as opposed to having shipped).
Back to the import options - I realize that there are a lot of die-hard machinists out there that frown on them. However, I am also a realist and have done enough research on machines to know that there are good results to come out of some of the choices out there. My drill press, for example - its from Taiwan and is older than I am. It's not a pretty machine, but again - it isn't the machine that makes the machinist.
Given the 12x36 ballpark size - and the features I've mentioned - are there any options that jump out to you that are worth mentioning in that class?
Are there any features that you would like to have that you don't, or that you have that you are darn glad you have? Are any of those features able to be added after-the-fact (like a DRO, CNC, power feed, etc)? Or is there an option, or options, that a machine needs to be built with from the factory?
What I am trying to figure out is how to not get myself in to the hole of out-growing a machine. The idea of getting a smaller, more basic lathe is certainly there. Then use that as a "starter" lathe and upgrade later. I suppose I'll see what time brings in ideas and options.
I did pass up a big floor mount 3 phase lathe, around a 14x50 or so, back in 2009 as I didn't have a place to put it nor 3 phase power. That is one of those situations that I look back on and just wish things would have been better on my end to make that work.
I have run lathes before in school - even CNC and ProtoTRAK controlled machines. Its been years since I have done any of that, though.
Power is a consideration. I think single phase 220 is probably the most ideal. I realize there are ways to get 3 phase with a home-brew rotary phase converter. That isn't out of the realm of possibilities, but I think that is one more thing that could make for an inconvenience. If going to 3 phase is key to getting in to a category of non-out-grow-able lathes then it might make more sense.
One last point/question:
My understanding is that DC motor drives for variable speed ability (usually seen on smaller lathes - 10x22 or less - as an option) loose torque at lower speeds within each range. Variable frequency drives supposedly offer higher torque. What comments can anyone offer in regards to this? All the lathes I've run have been constant speed 3 phase motors - geared and belt drive, 2hp and up.
On the same torque question/point - how important is gear range/RPM selection? Like some of the Grizzly's have 9 speeds and some have 8 speeds - 70-2000rpm range. Then some Precision Matthews in the same size range have 12 speeds 70-1200rpm or so. My theory is still the same "machine doesn't make the machinist" here - that the limitation in speeds isn't a big deal, but I would like some deeper thought/perspective from those that are using either - low speed count or high speed count, or variable speed drive?
Lots of points, topics, and questions, I know. Thanks for any further insight.