Which Lathe?

[bigngreen]

I personally have never found the foot brake useful on any lathe I've used with it, if I'm cutting metric threads and am forced to leave the half but engaged I'm just reversing and with drawing in the same motion then reversing and dialing back into the cut on the other end, course I can do this without burning a motor up because I spent the $300 to convert to three phase at the machine.
I like the idea of a foot brake, I've seen many guys wire a VFD and program it for braking, I've seen it wired to a sensor so the lathe would shut of and brake at a set point, which I found very interesting!!

 

[Bullet bumper]

You can instant reverse if you have a three phase motor but you can't with a standard single phase it needs to stop completely and then restart in reverse or it could damage the motor . So you get overrun that could crash the tool tip. The brake stops it dead . I don't want to use three phase even though I have it because it makes the lathe worth less secondhand and much harder to sell later . The OP was on a budget .

 

[Hired Gun]

I disagree that a 3 phase machine is worthless at resale time. I know you already know this but for the new guys shopping there is two ways to make 3 phase power in a small shop. For light duty use the cheap VFD Inverter for a couple hundred dollars works okay but derates the hp and torque from the motor. The more serious guys can get an American Rotary Digital Phase Converter. I got the 15 horse model for $1500 and it will run my 7.5 horse lathe and a 3 hp mill at the same time without derating the motors. On the lathe we use a VFD with 3 phase input and output to get us infinitely variable speeds. If we slow the motor with the VFD it does derate it a little. We were told to never go below 50% but haven't touched it in years. I guess the training wheels are off now. The mill has a variable speed head so it's used as is. Lot's of guys around here using the rotary phase converters. Some are even home made. My electrician said he could build one for about $150. They are using them to power some fairly large CNC machines and big old industrial wood working equipment as well as some pretty big old lathes.

Single phase machines are or can be prone to chattering in the surface finishes from the HZ cycles transmitting the pulses through the motor all the way through the gear boxes. Then is shows up in the finishes. The single phase Grizzly machines are very prone to this and it is tough to cure if you are affected.

As far as metric threads my machine has one mark on the thread dial that is for metric so we can drop the half nut anytime we want. We routinely thread to a solid stopping point on tennons and muzzle brakes. I hate the look of a thread relief on those parts. Whenever I see it I just cringe. On thin barrels with small thread brakes it doesn't leave much metal at all right where the tip is weakest.

As far as the foot brake we rarely use it and I would never do instant reverse even if I could. It just doesn't sound like a good idea. I would be interested is seeing someone do it though but not on my machines.

Here is one of ours back when we started out and we used to take pictures of our work. No time for that now. We do this with a DRO set to count down to zero where you want to stop. You can do the same thing with a dial indicator mounted on the carriage somewhere. We just stop and back out at the same time. With practice we can stop it within .001 or tighter even at 80 rpm. It's especially handy when single point cutting action threads. Makes them look super clean and very professional.

 

[jrock]

I bought the PM1236 last year. If I could have afforded more, I would have gotten then next size up. However, other than profuse leaking, which make-your-own-gasket material fixed up, I haven't had any issues. Customer service is superb and Matt knows everything about his equipment. I doubt the Grizzly lathes are much different as most of the lathes come out of the same factories, just with different features. I wouldn't mind a larger motor to hog out more material, so I just keep more stock sizes available. I didn't think I would use the coolant system but it really makes parting a breeze. Other features like foot break, roller bearings for steady rest, DRO just make life a bit easier but by no means are required to do good and accurate work. Get good indicators and tools.

 

[bigngreen]

In my area I can sell my lathe for more than I payed for it because of it running on a VFD, it's $200 and you can enjoy the benefits of three phase on single phase, IMO not a had call!

My VFD does not instant reverse, it ramps down then back in so it a nice reverse not an instant which I would not want.

 

[Bullet bumper]

I disagree that a 3 phase machine is worthless at resale time. I know you already know this but for the new guys shopping there is two ways to make 3 phase power in a small shop. For light duty use the cheap VFD Inverter for a couple hundred dollars works okay but derates the hp and torque from the motor. The more serious guys can get an American Rotary Digital Phase Converter. I got the 15 horse model for $1500 and it will run my 7.5 horse lathe and a 3 hp mill at the same time without derating the motors. On the lathe we use a VFD with 3 phase input and output to get us infinitely variable speeds. If we slow the motor with the VFD it does derate it a little. We were told to never go below 50% but haven't touched it in years. I guess the training wheels are off now. The mill has a variable speed head so it's used as is. Lot's of guys around here using the rotary phase converters. Some are even home made. My electrician said he could build one for about $150. They are using them to power some fairly large CNC machines and big old industrial wood working equipment as well as some pretty big old lathes.

Single phase machines are or can be prone to chattering in the surface finishes from the HZ cycles transmitting the pulses through the motor all the way through the gear boxes. Then is shows up in the finishes. The single phase Grizzly machines are very prone to this and it is tough to cure if you are affected.

As far as metric threads my machine has one mark on the thread dial that is for metric so we can drop the half nut anytime we want. We routinely thread to a solid stopping point on tennons and muzzle brakes. I hate the look of a thread relief on those parts. Whenever I see it I just cringe. On thin barrels with small thread brakes it doesn't leave much metal at all right where the tip is weakest.

As far as the foot brake we rarely use it and I would never do instant reverse even if I could. It just doesn't sound like a good idea. I would be interested is seeing someone do it though but not on my machines.

Here is one of ours back when we started out and we used to take pictures of our work. No time for that now. We do this with a DRO set to count down to zero where you want to stop. You can do the same thing with a dial indicator mounted on the carriage somewhere. We just stop and back out at the same time. With practice we can stop it within .001 or tighter even at 80 rpm. It's especially handy when single point cutting action threads. Makes them look super clean and very professional.

Who said " WORTHLESS "you are imagining things . I said , " worth less secondhand " Big old three phase lathes are harder to sell than a near new modern single phase lathe that suits more peoples home workshop needs . I have been offered a huge old lathe for nothing because they just want rid of it to install a new one . I can sell my lathe anytime I want because people can pick it up in a trailer take it home and plug it into a 15 amp power point ready to go not withstanding leveling .

 

[Hired Gun]

I don't want to use three phase even though I have it because it makes the lathe worth less secondhand and much harder to sell later .

Look what you found. The quote button and you wasted all that bandwidth getting everything including the picture. Very impressive. You're well on you way to being a full fledged ninja keyboard commando. Thanks for the lesson.

 

[shortgrass]

Obviously you have no experience in the technique mentioned . No one said it was "needed " . The technique was put forward as an option to illustrate what you can do with an instant stop foot brake after an incorrect negative post . People tend to knock what they don't like or don't use without knowledge of that subject . No one said that using a thread dial was bad in anyway , you are the one over the top getting all emotional over nothing .
Your comment about worn out junk is senseless and has no basis or relevance to the technique working . You have misread the posts , the term " needing the foot break " is not an accurate quote of what was said . You seem to miss one fact and that is most lathes have either a Metric or an Imperial thread dial and they only work for one . Foot brake works for both and is ideal for threading up to a relieved shoulder on a "GUN " barrel tenon .

OH! But I DO have experience with foot brakes on lathes! I worked for several yrs. in the tool repair shop in a bearing plant. We had a Wells/Index 10x54 mill and a Nardini 13x40 tool room lathe with a brake. I used the brake several times, on and off, and just never found it useful,,,,,, and I did a lot of threading with it. After I graduated from gunsmithing school (MCC class of '93, gunsmithing 2 yr program) I went work in a job shop that had an American Pacemaker, 20"x 96" with a foot brake. Again, I used it some, but it really wasn't all that useful to me. After all, how many revs are left when you clutch out the spindle and you were only turning 150 RPM. As for cutting a relief groove,,,, not a chance. I thread to the shoulder on a 1" to 1 1/8" dia tenon with 16 or more TPI @ 200RPM in the conventional manner. Childs play...... I've been machining since June of '74. That means I'll be gathering my 44th year of experience beginning in a month, most all of it OJT, not from YouTube. I used to thread a lot of 'gun' barrels when there has a lot of removable choke tube work. I've been threading rifle barrel tenons and muzzles for better than 23 yrs. I've never re-barreled a shotgun where the barrel threaded into the action, so I guess I've never threaded a " a "GUN"barrel tenon". Bigngreen gave good advice to the op.

 

[Bullet bumper]

None of that changes anything so you do have experience in some areas good for you . None of that makes what I said wrong in anyway you are just arguing for no valid reason . If I have two lathes the same size and basically the same features and condition and comparable brands , one is three phase and one is single phase . I can sell the single phase lathe easily and for more money . Large three phase lathes only appeal to a small percentage of the home workshop crowd and I know of a ware house full of them and they can't sell them for much money .

 

[Edd]

None of that changes anything so you do have experience in some areas good for you . None of that makes what I said wrong in anyway you are just arguing for no valid reason . If I have two lathes the same size and basically the same features and condition and comparable brands , one is three phase and one is single phase . I can sell the single phase lathe easily and for more money . Large three phase lathes only appeal to a small percentage of the home workshop crowd and I know of a ware house full of them and they can't sell them for much money .

I thought you had been interpreted incorrectly when you wrote worth less and had it interpreted as worthless. Then you wrote ware house.

 

[Bullet bumper]

" Worth Less " not associated with " Ware House "
Different post , different statement , ???? weird .

 

[shortgrass]

None of that changes anything so you do have experience in some areas good for you . None of that makes what I said wrong in anyway you are just arguing for no valid reason . If I have two lathes the same size and basically the same features and condition and comparable brands , one is three phase and one is single phase . I can sell the single phase lathe easily and for more money . Large three phase lathes only appeal to a small percentage of the home workshop crowd and I know of a ware house full of them and they can't sell them for much money .

bumper, I've got experience in more than 'some areas'. The only manual machine tools I've not had exposure to are planers. I've made many cutting tools, as up until the late '90s cutting tools didn't come out of a little plastic box, they started off as 'blanks' of high speed steel, and those were made into cutting tools using tool & cutter grinders and surface grinders and were regularly re-sharpened using the proper precision grinder. Either you knew how to make/sharpen cutting tools or your machine tools were worthless to you. I worked on the screw machine line from the fall of '74 until late '88 where I learned to make and sharpen tools. (If you don't know what a screw machine is, look it up! And no, they don't make 'screws', unless they'd be very special screws. I worked with 6 spindle Acme-Gridley 1 1/4" and 9/16" machines) That experience propelled me into every other aspect of machining. At any time while there, I could be asked to go set-up, make adjustments or change tools in the 'secondary' dept (gang drill presses, mills, the punch press that was used to broach splines on a small shaft or turret lathes. After I'd graduated from GS school, when I worked in the job shop with the American Pacemaker, I got my first introduction to CNC. I took some night classes to learn basic programing. But, guess what, the principals of cutting metal are the same, whether CNC or manual. Anyone who can come up with cutting an inch thread on a manual, inch lathe and not disengage the split nut, like you suggested, can be nothing more than self trained/YouTube trained and to be completely ignored on matters concerning machining/machine tools. These guys that buy a lathe, make a couple of good rifle barrels and are now 'machinists' haven't a clue, and most of the time can't solve their own problems that they'll encounter along the way......... Hired Gun has that much right, " a full fledged ninja key board commando".

 

[Trickymissfit]

OH! But I DO have experience with foot brakes on lathes! I worked for several yrs. in the tool repair shop in a bearing plant. We had a Wells/Index 10x54 mill and a Nardini 13x40 tool room lathe with a brake. I used the brake several times, on and off, and just never found it useful,,,,,, and I did a lot of threading with it. After I graduated from gunsmithing school (MCC class of '93, gunsmithing 2 yr program) I went work in a job shop that had an American Pacemaker, 20"x 96" with a foot brake. Again, I used it some, but it really wasn't all that useful to me. After all, how many revs are left when you clutch out the spindle and you were only turning 150 RPM. As for cutting a relief groove,,,, not a chance. I thread to the shoulder on a 1" to 1 1/8" dia tenon with 16 or more TPI @ 200RPM in the conventional manner. Childs play...... I've been machining since June of '74. That means I'll be gathering my 44th year of experience beginning in a month, most all of it OJT, not from YouTube. I used to thread a lot of 'gun' barrels when there has a lot of removable choke tube work. I've been threading rifle barrel tenons and muzzles for better than 23 yrs. I've never re-barreled a shotgun where the barrel threaded into the action, so I guess I've never threaded a " a "GUN"barrel tenon". Bigngreen gave good advice to the op.

best threading system I ever saw was the automatic back off used on Monarchs and the small Hardingh bench lathes. You set the end of travel, and the cross slide automatically backs off one full turn if memory is right. The idea must be copyrighted, or too difficult for the guys west of us. As for a brake, the only time I ever used one was when the spindle was running several thousand RPM. And even then it wasn't a foot brake, but one built into the machine spindle line.

Won't matter much anyway as 90% of engine lathes are never set up right from the first moment the power is turned on.
gary

 

[Bullet bumper]

bumper, I've got experience in more than 'some areas'. The only manual machine tools I've not had exposure to are planers. I've made many cutting tools, as up until the late '90s cutting tools didn't come out of a little plastic box, they started off as 'blanks' of high speed steel, and those were made into cutting tools using tool & cutter grinders and surface grinders and were regularly re-sharpened using the proper precision grinder. Either you knew how to make/sharpen cutting tools or your machine tools were worthless to you. I worked on the screw machine line from the fall of '74 until late '88 where I learned to make and sharpen tools. (If you don't know what a screw machine is, look it up! And no, they don't make 'screws', unless they'd be very special screws. I worked with 6 spindle Acme-Gridley 1 1/4" and 9/16" machines) That experience propelled me into every other aspect of machining. At any time while there, I could be asked to go set-up, make adjustments or change tools in the 'secondary' dept (gang drill presses, mills, the punch press that was used to broach splines on a small shaft or turret lathes. After I'd graduated from GS school, when I worked in the job shop with the American Pacemaker, I got my first introduction to CNC. I took some night classes to learn basic programing. But, guess what, the principals of cutting metal are the same, whether CNC or manual. Anyone who can come up with cutting an inch thread on a manual, inch lathe and not disengage the split nut, like you suggested, can be nothing more than self trained/YouTube trained and to be completely ignored on matters concerning machining/machine tools. These guys that buy a lathe, make a couple of good rifle barrels and are now 'machinists' haven't a clue, and most of the time can't solve their own problems that they'll encounter along the way......... Hired Gun has that much right, " a full fledged ninja key board commando".

You just using the thread to boast about yourself what a jerk.