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Requesting tips to speed up production of this simple part on manual lathe.

I often use the side of a tool holder as the Z stop when loading material, both in a manual lathe that has stops or a DRO, or in the CNC when manually pulling the bar out for the next part. Just move in -X enough that the raw stock hits the flat side of the holder and misses the insert.

Assuming you have a QC toolpost, another thing that helps a lot is to carefully set the stickout on your tools so they are at either nominal values (whole lead screw turns) or have some other useful relationship to the other tools. My main roughing tool is a CNMG, my main finishing tool is a DNMG. I have my roughing tool set at +.015" in both +X and +Z relative to the finishing tool. Once I've made a good part and have my dials set well I can then make cuts with my roughing tool until my dials match the finish size, but because they are offset it automatically left me my finish allowance. Then I swap tools without changing the dials and can cut my finish OD and face. Setting the tools like this isn't that difficult, I use shims behind the tool to adjust Z and setup a dial indicator with a flat tip for the X, tapping the tool around until the tip is where I want. Only the finish tool is important, the rest is just roughing.

I make notes with Sharpies on the top of the compound with what the dials should be for each feature, each diameter a different color and also make corresponding tick marks on the handwheels. Easy to clean off later. Not having separate roughing and finishing numbers greatly reduces the amount of info I have to keep track of.
 
My pal Mike-the-Pilot has a Colchester with a factory stop arrangement on the tailstock side of the saddle. Basically a long tube with many tapped holes to fit blocks carrying short screws to act as the stops working against another block fixed to the bed. Only one I've ever seen but it works well.
By any chance do you have a photo of this? Sounds very useful!
I've not read the entire thread to see if this has been suggested but I'd look at the DRO and see it has the ability to store tool offsets.
I am pretty sure it does, although I have never used that feature.
Thanks for the process description-

There's a ruler type stop that's perfect for first op work - I can't remember what they're called so hopefully someone else can chime in. I couldn't get my hands on one over here in the UK so 3D printed one - it uses a 3D printed carriage that runs along a piece of stock aluminium angle.
Could you post a picture of this?

I am very interested in stops for metalworking- all my experience with work stops has been with woodworking, and this is one thing that does not translate well, as in woodworking, usually the stock moves and the cutter is fixed, and in metalworking, usually the stock is fixed and the cutter moves.


Is the four way ratcheting tool post the same type that comes standard on most Asian import lathes ? Or is the ratchet feature something different? I have only ever used an Aloris type QC toolpost.
 
I often use the side of a tool holder as the Z stop when loading material, both in a manual lathe that has stops or a DRO, or in the CNC when manually pulling the bar out for the next part. Just move in -X enough that the raw stock hits the flat side of the holder and misses the insert.

Assuming you have a QC toolpost, another thing that helps a lot is to carefully set the stickout on your tools so they are at either nominal values (whole lead screw turns) or have some other useful relationship to the other tools. My main roughing tool is a CNMG, my main finishing tool is a DNMG. I have my roughing tool set at +.015" in both +X and +Z relative to the finishing tool. Once I've made a good part and have my dials set well I can then make cuts with my roughing tool until my dials match the finish size, but because they are offset it automatically left me my finish allowance. Then I swap tools without changing the dials and can cut my finish OD and face. Setting the tools like this isn't that difficult, I use shims behind the tool to adjust Z and setup a dial indicator with a flat tip for the X, tapping the tool around until the tip is where I want. Only the finish tool is important, the rest is just roughing.

I make notes with Sharpies on the top of the compound with what the dials should be for each feature, each diameter a different color and also make corresponding tick marks on the handwheels. Easy to clean off later. Not having separate roughing and finishing numbers greatly reduces the amount of info I have to keep track of.
This makes great sense, thank you!
 
Just reading through this thread gives me PTSD from my pre-CNC days :eek:.

I don't think there is any scenario where I could be convinced to make 100 of something on my manual lathe :crazy:. Sorry, I have no advice on how to ease your burden other than find someone with a CNC lathe.

Regards.

Mike
 
There's a ruler type stop that's perfect for first op work - I can't remember what they're called so hopefully someone else can chime in. I couldn't get my hands on one over here in the UK so 3D printed one - it uses a 3D printed carriage that runs along a piece of stock aluminium angle.
Could you post a picture of this?
???

It's called Stop Loc

I just use a vise jaw stop clamped on a strip of plastic.
 
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Just reading through this thread gives me PTSD from my pre-CNC days :eek:.

I don't think there is any scenario where I could be convinced to make 100 of something on my manual lathe :crazy:. Sorry, I have no advice on how to ease your burden other than find someone with a CNC lathe.

Regards.

Mike
Yup
If I had to do 100 of these today I would do it in my CNC knee mill
Set the auto saw up to cut 4 inch long or so blanks, drill a little block for the drill bits, one tool to turn and part, park at end of cycle so you can loosen the collet and drop it to length, tighten, push the button

Made some little replacement phenolic Gerstner knobs this way just recently. Could not get the radii correct but otherwise easy
 
Look up flip stop for wood working that'll give yah an idea for quick movable stop
 
There are several good solutions for this issue. Small turret lathe. Larger turret lathe. Or, a lathe with a repeatable QC toolholder that gives you control over both axes to within a thou. Another option would be one of those Enco tailstock mounted turrets. Put a turning tool or a box tool in one position, center drill and your drill in the others.
 

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Just reading through this thread gives me PTSD from my pre-CNC days :eek:.

I don't think there is any scenario where I could be convinced to make 100 of something on my manual lathe :crazy:
Regards.
Mike
Mike,
Try this one. Let's say I get good at this on the manual-
It takes 3 minutes to make a part.
I use 50- a year. 2.5 hours.
There is no call to make anything else with a CNC.
The shop rate labor and materials cost is 150 bucks an hour. $375.
7.5 dollars each- crazy, yeah?
Incorporated into a product using two, costing $1500. 1%.
It would take a long time to recoup the investment into machinery at that number.

If I was using even a couple hundred a year, I would be shopping it out.
What would someone charge to make 50?
 
Mike,
Try this one. Let's say I get good at this on the manual-
It takes 3 minutes to make a part.
I use 50- a year. 2.5 hours.
There is no call to make anything else with a CNC.
The shop rate labor and materials cost is 150 bucks an hour. $375.
7.5 dollars each- crazy, yeah?
Incorporated into a product using two, costing $1500. 1%.
It would take a long time to recoup the investment into machinery at that number.

If I was using even a couple hundred a year, I would be shopping it out.
What would someone charge to make 50?
For the cost of four of your $1500 assemblies you would never have to hand crank anything again :scratchchin: :D
 
Jeeze, you guys. A little dsm59 and these'd be a snooze. What are you bitching about, a couple hours easy work ? I just recently did a few hundred little warshers, job like this, it took longer to put them in plastic bags and seal them than it did to make them. On a south bend.
 
Jeeze, you guys. A little dsm59 and these'd be a snooze. What are you bitching about, a couple hours easy work ? I just recently did a few hundred little warshers, job like this, it took longer to put them in plastic bags and seal them than it did to make them. On a south bend.
Actually that shit drives me nuts when it takes almost as long to package as to make the damn thing.
 
Could you post a picture of this?
???

It's called Stop Loc

I just use a vise jaw stop clamped on a strip of plastic.

That's the one I was thinking of.

Below is a pic of the one I 3D printed. Great thing about doing it this way is that I can pop it on any length of aluminium extrusion to get an accurate stop for any length. Works great on a few longer parts I do where I need the part sticking out 3-400 mm

1716536820921.png
 
One comment I can not help but make: The OP apologized in his first post about making this thread which has produced some very interesting discussion. BUT his thread was quite remarkable because
unlike almost all other similar threads he actually provided all the information needed to answer the question without being prompted right up front. To top it off he specifically and politely (haven't we seen exceptions to that!) replied to those suggestions and made pertinent follow up questions. And, also remarkable, I think every response was right on-topic (not this one) and well-intended.

It seems like this thread deserves to be engraved in bronze and hung (CNC or classic Deckel Pantograph---your choice) in the PM hall of Fame as an example to be followed.

Well done!

Denis
 
Denis, thanks.
All, thank you for the suggestions, those stops are really interesting for a simple and effective way to control the length of a feature.
The rotary one must have some sort of ball and plunger spring detent, yes?

On my little 1340, (Acra-Turn, made in Taiwan, -it is , I think, what people refer to as a colchester copy? Slant head, 3 hp, about 1600-1700 lbs?) this has a clutch of sorts, I think it is a ball-spring affair on the feed rod-is this just to protect the gear train in event of a crash, or is it to be used as a routine disconnect for power feeding to a stop? I have never used it, it is slightly scary to think of running into a stop with the feed engaged. It is pretty stiff, it will drag the saddle along the ways with the saddle lock tightened down without releasing.
DSCF1519.JPGDSCF1520.JPG

As far as the CNC comments, we make very few parts a year, I am almost 70 years old, and the payoff time for the cnc would likely be after I am dead. The comments on cost assume the infrastructure to support such a machine exists, that being power, floor space, and, most importantly, knowledge- I have absolutely no clue how to use CAD or G-code or any of these mysterious acronyms. After I retire maybe I will get one to play with. They are amazing- all the intricate mechanical aids we have for industry of all types devolves to one thing- how to bring a tool to a certain point in space at a certain time. Laser, needle, cutter, anything- and now it is an instruction to a motor and a screw.
 
For quantity 10 at a time, maybe I'm the weirdo, I'd chamfer the first end, cutoff a blank, wait until I had all ten blanks, set up a collet stop, face and turn the end with the reduced diameter, remove collet stop, spot all 10 for ID edge break, then drill all 10 through. I'd rather swap parts than tools for something like this.

I'm guessing that's because you've got a manual lathe like a Hardinge with a lever collet closer that operates while the spindle is turning and so it's faster to change parts than to change tools. The OP seems to have the opposite equipment situation where it's really slow to change parts, but fast to change tools.

I've not read the entire thread to see if this has been suggested but I'd look at the DRO and see it has the ability to store tool offsets.

It's way faster for a simple repetitive part to make marks on the cross feed dial, use a Trav-A-Dial, and ignore the DRO off. DROs save lots of time on one-offs, but fiddling with them is slow and it's too easy to select the wrong offset when producing a a few dozen identical parts like this. I might use the DRO to set things up, but then take it out of the equation for the sake of speed.

On the X dial I put a tick mark at the X ordinate, draw a little symbol showing the operation (a drill shape, a chamfer shape, etc.), an arrow showing which direction I'm approaching from when there's both ID and OD cuts, and then write the Z ordinate next to this.

Hard stops would be fastest, coordinates written on cross slide dial + Trav-A-Dial is second, and fiddling with DRO very slow. Since the OP lacks a Trav-A-Dial best option might be to use DRO for Z only, but to leave it at a single offset. Still much slower to hit a number than with an analog indicator though.

I was getting chatter at higher speeds- probably need more feed?

Are you parting right at the nose of the chuck? Are you using a spindle bore liner that fits your stock?

THe stock was parting off with a burr around the hole, so I was using a center dril to get rid of the burr and chamfer the ID.

Right, but you can chamfer both the ID and the OD with a single 90 degree engraving tool like this:
D-bit.png
I think it is a ball-spring affair on the feed rod-is this just to protect the gear train in event of a crash, or is it to be used as a routine disconnect for power feeding to a stop? I have never used it, it is slightly scary to think of running into a stop with the feed engaged.
There might be a knob to adjust the force at which the clutch releases. But, I doubt power feed will save any time. Only possible advantage might be more consistent finish.

As others have said, a small lathe with collet closer and possibly turret is the way to go. It will also be much safer because you won't be sticking your hand near a spinning chuck. At the very least I'd get a 5C keyed closer like below. Slow, but much safer than a 3-jaw.
5C.png

And finally, have you perused the spacers over at McMaster-Carr? They might have something pretty close that you could use as a blank and just add the step feature.
 
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