New Pm 1030v Lathe

I'm sure you will figure out finishing the chess set.
I'll be watching
 
Shooter -

Could you give a PM1030V noob a quick synopsis of threading on this machine?
 
Shooter -

Could you give a PM1030V noob a quick synopsis of threading on this machine?
Sure thing. The big parts are:

1. Change gear set up
2. Tool Set Up
3. Use of the thread dial
4. Actual threading operation

I will take this from the point that you know what thread you want to cut, the stock is secured in the chuck and it is turned to the correct diameter.

Change Gear Set Up

First up is setting up your change gears. This will make sure that the carriage (part that moves while the machine is cutting) advances the correct amount while the spindle is turning so that the thread is cut. Decide your thread pitch (threads per inch) and locate that pitch on the chart on the change gear cover on the left side of the lathe. It will give you an arrangement of gears to get the right ratio. Lets say you want to do 24 TPI. The chart tells you to use "H-55, 40-60, 80-H". I am not exactly sure what the H is supposed to stand for, but you use a spacer in that case. That tells you that when you change the gears, the bottom one will be a spacer then the 80 tooth gear, then above that you will use the 40 and 60 tooth gear (40 tooth engages the 80 tooth), then the top gear set that will mesh with the spindle gear is a spacer then the 55 tooth gear. When you are putting the gears onto the little keyed bushing that goes inside them, be careful and dont force them in. They are made out of some very soft and easily deformed metal. If they take more than a light press with your thumb to slide in, take a file to your gear and open it up slightly wherever it is sticking. If you force it, it will deform and then they won't spin. When you install the gears onto the machine, take a piece of paper and put it between the gears while you mesh them together. Once the paper is crushed between the teeth, tighten the gear in and turn the gears to slide the paper out. That makes sure the spacing between them is good. Make sure you set the gear knob on the gear box to the right setting (A, B, or C). That's it for the gears. I usually spin the chuck with my hand a few times just to make sure everything is spinning right.

Tool Set Up

Now that you have your change gears set up, its time to set up your tool. First thing to do is set the compound. There are 2 bolts right above the base that you will loosen to rotate it. You want to set it to about 29.5 degrees. It doesn't need to be perfect, but do your best to get close. This will make sure the tool is cutting on one side of the thread instead of both sides. This will cut the cutting force in half and make it much easier on the machine (think turning vs parting or using a form tool). Use a fishtail gage to grind a HSS tool to the right shape. You want to get it as close as you can here. You can try using the carbide triangles or threading inserts, but I never had much luck with those. It goes better with HSS. Make sure the tool is sharp and the cutting edge is touched up on a stone. Also give the nose a slight radius. Also use the fishtail gage to make sure the tool is perpendicular to the work. That part is important too. Once the compound is set to 29.5 degrees and the tool is squared up to the work, you are ready to move on.

Thread Dial

One of the things that always tripped me up about threading was using the thread dial. It is used to make sure the half nuts are engaged in the same place on the lead screw so that the tool enters the cut in the same place each time. When threading 24 TPI, you can engage the half nuts on 1, 2, 3, or 4. There is a chart that tells you which numbers you can use for each pitch. If you don't want to learn about that, just pick one number and use that number each time. **Note, if you are doing a metric thread, you can't use the thread dial. Don't disengage the half nuts at all during the cutting operation.**

Threading Operation

Once you are all set up and know how to use the thread dial, its time to thread. First, set the compound dial to zero. Then turn on the lathe and touch off the tool. Zero the cross slide. I usually put layout dye on the part to be threaded and use a parting tool to put a thread relief at the end of the thread. If you don't know what that is, its a little slot put at the end of the thread to give you a place to stop the tool. I usually do mine 5ish thousandths deeper than the thread should be. Ok, now its time to take your first pass. First pass is a "scratch pass". I usually feed in .001", turn the lathe down to about 100 RPM, and engage the thread lever. The thread lever is the big one in the bottom right of the carriage. The one up and to the left of that is for the power feed and cross feed. Once it is engaged, watch the cut and try to use your right hand to disengage it at the end of the cut and your left hand to retract the cross slide. Run the carriage back to the starting position and turn the lathe off. I use a thread gage now to double check that the pitch I have is right. If it is right, run the cross slide back to zero, use the compound to feed in between .003" and .007" depending on material and how confident you are. Repeat this until the thread is cut. Every 3 or 4 passes I usually do a spring pass where I do a cut without feeding any deeper. There is a "correct" way to know when your thread is done, but I don't have the right stuff to do that so I do it like this. If I have the part it will be threading into, once it threads on, it is done. If I don't have that part, once there is no more blue on the top of the threads (or very little blue), the thread profile is done.

I think that about covers it. Does that help?
 
Does that help?

I'd say that sums it up incredibly well. I've printing the "Shooters Guide to Threading" out and it'll be in my filing cabinet, next to my lathe.I really appreciate it.

I'm planning on YouTube binging tonight on some threading videos, but your comments really put it all into perspective.

Now I guess it's just a matter or giving it a shot.

Thanks again.
 
I'd say that sums it up incredibly well. I've printing the "Shooters Guide to Threading" out and it'll be in my filing cabinet, next to my lathe.I really appreciate it.

I'm planning on YouTube binging tonight on some threading videos, but your comments really put it all into perspective.

Now I guess it's just a matter or giving it a shot.

Thanks again.
Im happy I was able to help. I know it is intimidating at first. When I first had my 7x12 lathe, I didn't think I would ever be able to cut a decent thread. I think it took me 5 tries to get it right (most mistakes wouldn't have happened with the 1030v) but after the next 5 threads, it was as easy as any other lathe operation. It isn't nearly as hard as it looks once you have done it a few times. Good luck!
 
For your first threading sessions it is useful to do dry runs. Set everything up, and then move the carriage far away from the work. Practice engaging the half nuts at the right spot(s) on the dial, and it is not near the number, it is in the same spot every time. It might be a little to the left or right of the number, or dead in the center, but once you make a cut, see the same picture every time. You can engage the half nuts slightly early and the handle will stop half way until the screw and half nuts finish lining up, and will then drop in at the correct spot. After you have practiced cutting air for a while, and you feel like you have the correct muscle memory, then try it well away from the work, learning the timing of releasing the half nuts at the desired spot and backing out the cross slide. Finally, go for it for real. Start with the tool well to the right of the work until you are very comfortable threading. If something goes wrong, like missing the correct threading dial engagement, just disengage the half nuts and start over. If you start too close to the work, the work can be ruined by the time you stop the tool. Lots of margins and slow spindle speed at first, give yourself all the time you need to not mess up. Speed will come with time, practice, and experience.
 
Good description related to threading. My 1030 has served me well for two years, my jobs now require a bigger machine but until that the 1030 was a good choice. I would like to keep both but room dictates one needs to go. Now just need to find a local needing a good smaller lathe. I'm sure the average home shop would be pleased with one.
 
Well, I've threaded..

I didn't change the gears, I just set everything up and practiced threading.

My threads, who knows what pitch, I think are too tight, as it gets deeper into the cut, it's like it's turning the threads off the work.

I also only have a carbide insert, I need to try some HSS bits, but I need to pick up a jig for grinding the threading tool.

158a5bef02809fd47a93a29618b9e14e.jpg




Sent from my iPhone using Tapatalk
 
Well, I've threaded..

I didn't change the gears, I just set everything up and practiced threading.

My threads, who knows what pitch, I think are too tight, as it gets deeper into the cut, it's like it's turning the threads off the work.

I also only have a carbide insert, I need to try some HSS bits, but I need to pick up a jig for grinding the threading tool.

158a5bef02809fd47a93a29618b9e14e.jpg




Sent from my iPhone using Tapatalk
For some reason, your picture shows up in the email alert I got and the reply quote, but I get a red X in the actual thread.

Looks like you had a good practice run. If you didn't change the gears and just used the feed gears, you will have a very very fine pitch thread which looks like what I am seeing. I counted roughly 40 TPI, which means the max thread depth is only .016". To get those to form well, you would probably need a sharper tool. The threading carbide inserts usually specify what range of thread they are meant for. They usually have a bit of a radius on the nose and larger inserts have too much of a radius to do fine threads.

But they actually look like threads which is a good start. My first go, if I showed you what I ended up with and told you I was threading it, you would think I was doing it with a chainsaw after 10 beers.

Is that a chip guard you have at the bottom there? If so, I would love some details on it.
 
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