Help building radius turning attachment

[jwmelvin]

Yup, if you’re worried about what the tool looks like on the inside, make a new arbor. I care about function and you can achieve the same function with your existing arbor. Efficiency is a worthy concern, in my view.

 

[Aurelius]

OK. The AXA holder is 77mm long, plus two flanges (.125" x 2 ~= 6.5mm). 77+7 = 84mm + the Belleville/washers + handwheel = ???
It looks like things would be much simpler if the straight shank was at least 100mm long. Can you buy a new arbor with a 100mm long shank?

I'll take a look at getting a new arbor but, honestly, I am not hopeful. I did not find many 5/8" straight arbors to start with and that number gets whittled down even further when you look for the threaded end. If you happen to know of any place that might have a longer shank, please let me know.

I also don't know exactly what your skill level is of what skills and equipment you have access to.

As far as tools, I am currently working on getting my lathe aligned. I am going into penmaking so all of the tooling I have is meant for acrylics. Aside from the lathe, I have a bandsaw and a belt/disc sander along with the usual hand tool assortment (drill, screwdrivers, sockets, etc.). You mentioned it later, but I have no welding equipment of any kind.

The lathe is the first big tool for me which is why I find it very frustrating that everybody's first answer is always to go to your mill and it's so easy to just make this little thing. For me, I would need to try to use the lathe as a mill and that would require an additional attachment that I don't have. I knew going in to this that there would be a learning curve but I was not expecting a "simple" project like this to get into the weed so quickly.

What say you?

IMO, continuing with a "too short" arbor is unattractive in the extreme (how's that for friendly language?). That's not to say it's not possible. Different people have different ideas of what constitutes a nice piece of tooling. Trying to continue using a "too short" arbor isn't attractive to me.

Thank you for all your help. At this point, it is clear that I need to take a step back to reconsider a number of aspects of this project. At this point, I don't have the tooling or, more importantly, the skill to make a new arbor. I feel like having a properly sized arbor made by someone else will likely cost more than I had originally intended the entire project to cost and I don't really have to much else that I have access to. Even some of the "simpler" things like your suggestion to thread the precision stock would involve purchasing a die in a size I don't need for anything else. The entire point of this project was to give me a capability beyond simply using a form tool get rounded ends on the pens I plan on making and it is feeling more and more like it would be cheaper and faster to just try out the form tool and revisit this at a later time.

 

[extropic]

@Aurelius

I think I understand your last reply.

I also looked for a longer 5/8 arbor and came up dry. It would be on the light side for a 3" boring head (1-1/2-18 mounting thread).

One small clarification. Regarding "thread the precision stock", what I had in mind was tapping for a female thread, not a male thread. No die required.

I don't mean to beat a dead horse, but you didn't tell us what lathe you have and whether or not it has a 4 jaw chuck and steady rest.

 

[Chewy]

It helps now that you told what it is your trying to do. You have just bumped up to the hard facts of machining. It costs 1-4 times the cost of the machine for tooling. In your case, since you are doing pen turning & probably shakers, You need very little in the way of "big" machines. A milling attachment for your lathe will do you for a long time and be a good investment. You always have to slot or flatten something and sooner or later you will have to drill and tap something, just in your case not very big. I am well aware of what is needed for pen turning as my wife has been doing it for a couple of years. I make, modify stuff all the time. I make the pen barrel bushings and that alone improved her overall pens a bunch.

The radius turner that you are asking about and the advice you have been given is far and away overkill. The turner will be able to do everything and very accurately on wood through stainless steel. You don't need that. In your case, I would make a small steady rest and rough turn the acrylic with a very small lathe tool or use an engraver. Clickspring does brass all the time this way. Furthermore, you can use a form tool to make it perfect. Take a piece of flat HSS and using a carbide grinder bit, slowly work it into the HSS until you get the desired radius. Hold it to the item and shave the piece. I know this works. I turn 5/8" 12L14 and 6061 handles all the time. I rough out with a cutting bit and file and then shave with the form tool. Looks like a store bought item for $6 in HSS blank.

My wife has gone through two different pen blank drilling jigs. I have finally made her one that will work. It bolts to the drill press table, but doesn't stop the drill press from normal use. It self centers the blank, has a guide for perfect table-drillbit alignment, and can lock in place for repeated drilling as most blanks are 3/4" square. It also handle square stock up to around 3" for center drilling shakers. I will offer plans for sale later this year. The materials cost was over $60 last summer and it takes 2 days or more for all the machining with medium size hobby machines.

My project this week is to make a t-slot piece of steel 60" long to mount a 48" log carrier to cut 36" long logs for a machinist tool box on a band saw. I need the steel, clamp, miter slot rails, wood and 2 floor supports to hold the weight. After that it is easy. I need to mount a wooden clarinet onto the metal lathe cross slide for line boring. I have to cut a counter-bore in the end for a replacement tenon, which i will probably also make.

My advice is to not get discouraged in what you are doing. Present the idea first along with equipment you have available. Then pick through the answers. There are a lot of smart experienced people on this board. I would love to have the radius tool you are making, but I'm turning steel up to a couple of inches in diameter.

 

[Aurelius]

I don't mean to beat a dead horse, but you didn't tell us what lathe you have and whether or not it has a 4 jaw chuck and steady rest.

My apologies, I meant to include that info. I got a PM-1228 and, yes, I have a 4-jaw to go with it (ER40 collet chuck too if that matters). The steady rest was included but I’ve only just opened the box to confirm it’s existence, I’ve never had a need for it before now.

@Chewy
Thanks for the encouragement. I’d love to see you wife’s work.

I’m actually diving into the deep end and going completely kitless which, in a lot of ways, is actually easier. I think people think it’s harder because of the transition from kits requires some different tools and skills, but I did my homework and am actually pretty confident in that side of things. They aren’t completely straight, but I can already make caps that properly thread onto barrels and sections that fit the bodies. It was when I got to working on putting nibs units in sections that I started thinking about depths and really dialing in the measurements and that is when I saw the twist that I am working out now.

I did want to point out that I am aware most people turn rounded elements by hand on a wood lathe but the reason I am not going that route is that I am dealing with RA and that has significantly decreased my confidence in my ability to do things like that safely. There are also a couple of other cool things I could do down the line with the radius turner.

Also, I’m sorry if I came across as discouraged. In my mind it is more like triage. I am being very conscious of taking manageable step so as not to get discouraged. I am getting the machine dialed in and I know there are skills I need to develop and tools that need to be made. It’s just a matter of what order that happens in and I don’t want to half-ass building something like this just to get it done sooner. In this case, if I need a new arbor, I’m out about $40 which is not that big a deal in the grand scheme of things. My feelings were more based on thinking I was almost done and now having to go back to the drawing board for a couple elements.

 

[Chewy]

I too have the 1228 lathe. I used a ER32 collet setup at first and added in the 5C collet chuck. I'm pretty well setup for all sizes for pens. Wrong kind of steady rest. I mean one like a wood lathe, not the kind on a metal lathe. Now, when you work out multistart threads let me know. My wife has been transitioning over to fountain pens and has been bugging me to do 3 start threads. She is eying $1K pens out of exotic woods and materials.

Until you get years down the line, every time you go to do something, you will have to get something. Case in point, 3 years ago I bought her a used $125 Craftsman lathe mounted on a bench. Now a single turning tool costs more then that. Everybody on this Forum can tell you about that rabbit hole.

I started setting up to do larger steam engines. I'm making a speed reduction setup to work the larger diameters. Now that she has got serious in doing musical instruments again, I'm adding in tooling for 0-4 size screws and stuff. Just drew up brass laps for flattening tone holes.
2 days ago, a wind storm blew down an oak tree on an out building. Today I'm spending around $150 to make this log cutting sled. In the end I will make a wooden machinist box that will rival a famous box maker. His version is around $4K.. Mine is actually a little bit bigger with more drawers, so I would say it would probably be closer to $5K. I will have around $4-500 in it total and I'm not counting in the $700 building replacement. And the money just keeps on going!!!!

Disconnect your thread dial indicator. It needs to spin freely. The one on mine gaulled up after 3 years and stripped the gear. $50 and 5 weeks later, still waiting on replacement. A nice person on this forum did a 3D printer gear and $14 and a week later it worked. I leave the indicator backed out now until I thread something.

Good luck, and post some pictures of the pens you have made.

 

[extropic]

@Aurelius

Your lathe is certainly up to building a radius turning attachment. You know your own circumstances better than the rest of us. If you would prefer to continue discussing how you can proceeded with the project, just say the word. There are innumerable ways to skin that cat. I'll bet we can converge on a way.

 

[Chewy]

@Aurelius

Your lathe is certainly up to building a radius turning attachment. You know your own circumstances better than the rest of us. If you would prefer to continue discussing how you can proceeded with the project, just say the word. There are innumerable ways to skin that cat. I'll bet we can converge on a way.

Don't stop now!! I have been following the thread because I plan on making one too! Looking at the information on the Belleville washers and thrust bearing to see if I want to incorporate them. I did order the round carbide insert that was shown in the video I posted. I can always use a radius cutter anyway. I'm using a HSS one that I made currently.

 

[Aurelius]

Now, when you work out multistart threads let me know. My wife has been transitioning over to fountain pens and has been bugging me to do 3 start threads. She is eying $1K pens out of exotic woods and materials.

If you mean single point threading stuff, that's way down the list. As of now, I got in on a group but over at penturners.org and picked up the m7.5x.5, m10x1, and m13x.8 taps and dies I needed. I also went ahead and grabbed the m14x.8 set from Turner Warehouse since I know I'm going to want to make bigger pens. Especially working in resins, tap and die is just so much easier. That said, at some point I am going to figure out threading because I think something like acme threads would just be cool. Until then, I got a set of tailstock tap and die holders from nichetools.com that are great and allow me to switch easily.

Disconnect your thread dial indicator. It needs to spin freely. The one on mine gaulled up after 3 years and stripped the gear. $50 and 5 weeks later, still waiting on replacement. A nice person on this forum did a 3D printer gear and $14 and a week later it worked. I leave the indicator backed out now until I thread something.

The lathe has only been in my basement for 3 months and, due to a backlog with my electrician, only had power for a little less than two. The dial seems to be working just fine for now but, admittedly, I'm not really using it at all.

Good luck, and post some pictures of the pens you have made.

Just as soon as I have something I can be proud of, you betcha!

Your lathe is certainly up to building a radius turning attachment. You know your own circumstances better than the rest of us. If you would prefer to continue discussing how you can proceeded with the project, just say the word. There are innumerable ways to skin that cat. I'll bet we can converge on a way.

Thank you. I am going to try to source a longer shank and then I plan on incorporating most (ok, all) of the things you suggested around thrust washers and Belleville washers. I'm going to call tomorrow and see if I can cancel the bronze bearing order as well and get the shorter ones you recommended. I measured and those will definitely work. If I can get he shank figured out, I can definitely see this coming together. I'll post more when I have it.

 

[extropic]

Buying a longer 5/8" SS arbor would be great, but I'm not optimistic that they are available.
If you can't find one to buy, let's discuss options that are doable.
I'm glad to read that you're willing to move forward with it.