How to duplicate a 2D shape on a lathe without makin a special bit?

[DJ Bill]

FOr my first lathe project in over a decade I am taking on some bead roller dies. I am attempting to match a unique bead design on Willys jeep parts. It is not symmetrical, and I have made a cast of both the negative and positive shape that I want. They are fiberglass, about a half inch thick and two or so inches wide. Where I cut them with a band saw you can see the exact profile I need for the die.

I was thinking that somehow I need to mount the part to the compound (maybe with my compound mounted rest somehow? ) and use a dial indicator against the profile casting to keep from cutting too deep, with a narrow but rounded tool bit. I'd use the compound and tool holder handwheels to do my x/y directions. I have a feeling I will be finishing off with a file and similar tools.

Any thoughts on how to do this appreciated. I will be cutting down a 3 inch piece of cold roll, already working on the shaft hole on the inside of it, and I also have the major diameter cut.

 

[Syaminab]

FOr my first lathe project in over a decade I am taking on some bead roller dies. I am attempting to match a unique bead design on Willys jeep parts. It is not symmetrical, and I have made a cast of both the negative and positive shape that I want. They are fiberglass, about a half inch thick and two or so inches wide. Where I cut them with a band saw you can see the exact profile I need for the die.

I was thinking that somehow I need to mount the part to the compound (maybe with my compound mounted rest somehow? ) and use a dial indicator against the profile casting to keep from cutting too deep, with a narrow but rounded tool bit. I'd use the compound and tool holder handwheels to do my x/y directions. I have a feeling I will be finishing off with a file and similar tools.

Any thoughts on how to do this appreciated. I will be cutting down a 3 inch piece of cold roll, already working on the shaft hole on the inside of it, and I also have the major diameter cut.

Have you seen how keys are made? With a pattern, you can cut a printed pattern and use a follower on the crosslide.

 

[DJ Bill]

Yes, I know exactly what you are talking about, I own several key makers. !!! That is pretty much what I was thinking about , never connected it to the key machine. Now to build something to hold the pattern..

Thanks for the reply!!

 

[easymike29]

Can you duplicate the profile in a CAD program? If so you can then extract the x/y movements and also have a permanent record.

Gene

 

[Tony Wells]

I showed this on an old thread that has been lost just as an example of a visual trace method. You can use this with external and internal shapes, as long as the tool tip/shape is the same as whatever you trace with. I drew a circle and printed 1:1 for this example.

 

[Syaminab]

I showed this on an old thread that has been lost just as an example of a visual trace method. You can use this with external and internal shapes, as long as the tool tip/shape is the same as whatever you trace with. I drew a circle and printed 1:1 for this example.

Beautiful Example. In my language is called Pantografo.

 

[n3480h]

This thread is very helpful. I recently posed a similar question, and had planed on making a special tool bit to duplicate a turned shape for 4 pieces in brass barstock. What's suggested here may be a faster and easier way. Thanks guys.

Tom

 

[kevin]

You can find some links at the link below which may be useful (scroll down to Tracer/Duplicator):

https://sites.google.com/site/lagadoacademy/useful-links#lathetools

FOr my first lathe project in over a decade I am taking on some bead roller dies. I am attempting to match a unique bead design on Willys jeep parts. It is not symmetrical, and I have made a cast of both the negative and positive shape that I want. They are fiberglass, about a half inch thick and two or so inches wide. Where I cut them with a band saw you can see the exact profile I need for the die.

I was thinking that somehow I need to mount the part to the compound (maybe with my compound mounted rest somehow? ) and use a dial indicator against the profile casting to keep from cutting too deep, with a narrow but rounded tool bit. I'd use the compound and tool holder handwheels to do my x/y directions. I have a feeling I will be finishing off with a file and similar tools.

Any thoughts on how to do this appreciated. I will be cutting down a 3 inch piece of cold roll, already working on the shaft hole on the inside of it, and I also have the major diameter cut.

 

[Deny1950]

Tony that is a good and easy way to duplicate a part. Although probably not a 100% but would be close. Thanks for that one never thought of that.

 

[Tony Wells]

Well, it's not really supposed to be precision. I've done some decorative work with it, and as long as you draw it to scale, you can follow the trace pretty closely and then polish out the tool marks and it comes out pretty decent. If you don't have a flat spot to mag stick the pattern, you can use a board across the ways or something. It also helps if your tracer "stylus" has the same shape and size as your cutting tool. I have used a Iscar 0.062 full radius grooving tool to cut, following a 1/16" dowel pin held in the mag base. No problems so far.