I'm back from my vacation in Idaho and ready to end my isolation from the internet!

I'm in the process of making a vide of the Spring Center project, but it isn't finished. I tend to be long winded and over-explain things, so the video for making the nose cone was 30 minutes long – despite the fact that the part can be made in about 10 minutes. 

A member by the name of Troy O posted pictures of the process for using the lathe to perform the milling cuts (so if you don't want to use your mill, or don't have a mill yet, the project can still be finished completely on the lathe). Here's a link back to the original project and Troy's instructions.

http://www.projectsinmetal.com…..athe-mill/

Anyway, here's the process I used.

The Nose:

1. Start by chucking a 2.75" long piece of steel for the nose cone. Use a 3-jaw chuck. Use something slightly larger than the finished OD (which is .750). I think I used 7/8" round stock. Chuck the part so that 1.75" is sticking out and face and center drill then end. You should have 1" securely held by the chuck jaws. If this is too short for comfort, start with a longer piece.
2. Once center drilled, support the end with a live center seated in the tailstock. Then reduce the shaft diameter to 0.499 along the 1.5" length. Take light cuts until you get used to your lathe's capabilities. 0.005 or so. Maybe 0.010. As you approach the final diameter of 0.499 take very light finish passes (0.002 or so) until you get to the final diameter. If you're having trouble getting a good finish you can reduce to 0.500 with the tool and use medium to fine grit sandpaper supported by something flat (like a file) to evenly reduce the diameter the last thousandth of an inch to .499. You can even use scotch-bright with cutting fluid to give it a nice shine. Note: I used High Speed Steel (HSS) tooling to cut this part because the carbide inserts I had gave it a terrible finish. You might want to do the same.
3. Reduce the end of the shaft to 0.375 for a length of 0.05 (this creates the notch for the spring to sit in).
4. Deburr any sharp edges with a light touch of a file.
5. Remove the part and flip it so that 1.250"  of the 1.5" you just cut is held by the chuck jaws. Then reduce the diameter of the end sticking out from 7/8" (.875) to .750. Use very light passes since you're not supporting the end with the tailstock. 
6. Face the end so that the cone portion is only 1" long (total length of the part should be 2.5" with about 1.25" chucked)
7. Set your compound at 30 degrees to cut the cone. Take very light passes (.005 or so) until you have a fairly sharp point. Polish with sandpaper and file if necessary. 
8. Follow Troy's setup for drilling the hole in the nose cone using the lathe. Or use a mill.

The Body:

1. Using the same 7/8" stock, chuck a 3.75" piece so that 1.5" is sticking out. Face, Center drill and support with a live center in the tailstock.
2. Reduce the diameter to 0.500 along the shaft for 1.1" and chamfer the end.
3. flip the part so that .750 of the 1.10" is chucked and face, center drill, and support wit a live center.
4. with the 2+" supported with a center drill, reduce the diameter from .875 to .750 and polish.
5. Remove the live center and replace with a .250 drill. Drill to a depth of 2.2" Note, if you feel like the part isn't adequately supported, you can re-chuck the part so that the 3-jaw chuck is holding the part by the .750 diameter of the shaft, but re-chucking may result in a loss in concentricity between the part's OD and the ID of the bored hole. 
6. Step up in drill sizes until you're at a 31/64" drill. Ream to the final 0.50 diameter. 
7. Chamfer and deburr edges. 
8. Follow Troy's steps for milling the .250" x 1" pocket in the side, or use a mill. 

I purchased a spring that fit (for about $1) but you can also make one out of piano wire (or some other spring steel wire) by chucking an appropriately sized bolt or (better yet) a piece of all-thread in your lathe jaws and wrapping the wire around the threaded bolt. I won't explain the process here because I don't want someone to get hurt by a piece of piano wire whipping around – just go buy yourself a spring that fits. 

I don't think I missed anything, but I might have. Let me know if these directions help. Good luck!

No problem. Since the spring center was actually the very first thing I ever turned on a metal lathe I remember how puzzled I was at a few of the steps. Now making one would be simple, but if you've never done it and it's your first project it seems a lot harder. If you deviate from the steps above and find a simpler method be sure to let us know. There's more than one way to do it, that's for sure. 

Use a v-block in a vise to hold the part steady while you center drill, drill, and then tap the hole. Don't move the part once you've started the process, that way the center drill, drill, and tap all line up perfectly. In the future, this would be the perfect place to use your spring center because you'd put it in the chuck to help align the tap. Since you don't have one yet you just have to be careful as you tap the hole. You could put something with a 60 degree point into the drill chuck and just put pressure on the quill to help keep it aligned, but it's not really necessary if you're careful. 

If you're going to make your own spring might I suggest piano wire? Do you have a local music store that you could buy some from? It works great for making your own springs! I've also heard of people using welding wire, but I'm not a welder so I have no idea what type or size might work. I'm not sure if a paper clip would have enough spring in it to work well. You really need a piece of spring steel wire. Feel free to wind the spring on the lathe if your lathe can go slow (like 30 RPMs). And this is one of the rare times where gloves would be a good idea, just don't get a glove caught in the chuck. But at such slow speeds it's pretty safe. 

Chuck a suitable diameter bolt to wrap the wire around. I drilled a hole in my bolt to thread the wire through, then folded it over so that I could put a fair amount of tension on the wire as the lathe pulled it through my gloved hands and wrapped it around the threads on the bolt. Remember to wear eye protection too – if the wire breaks or comes loose it will be coming back in your direction.

Hi Don, 

I just learned something today thad might be of help. You're on the right track with the idea of center drilling and drilling the start and end of the slot, but it isn't necessary if you do one of two things.

You can either use a 4-flute end mill that is undersized for the slot and cut the slot to length. Then true up both sides to width. If you use a full sized end mill to cut your slot in one pass you'll get an ugly oversized slot.

Your other option is to use a "slot drill". This is basically a 2 or 3 flute end mill that can be used to plunge and cut slots. In america they are sometimes referred to as center cutting end mills. 

A discussion of this exact topic can be found here:

http://www.projectsinmetal.com…..head-mill/