If I may add my 3-1/2 cents. You already have all the information you need to solve the problem with the equipment you have on hand. The answers given above are all correct. You just need to solve the problem. You need a lathe, a test indicator mounted to crosslide/compound and a chuck to hold the part.

If you are not familiar with Advanced Innovations, Austen Texas, here is a link to one of his videos:

. It tells how to use a ball to determine depth of chamfer. That is not what you are doing, but it is one of a series of videos telling how to use math to solve a problem. The math comes down to using a right triangle to solve problems. I started a couple of weeks ago inventing and solving problems just like yours. Blame Joe, it got addictive.

You have the base of the triangle (b) which is .65. your drawing looks like a 30/60 triangle. Entering the following information b=.65 B=30 A=60 gives the following dimensions:a = 1.126 b = 0.65 c = 1.3. c is the length of the angle cut. Don't shoot the messenger. I just used your drawing and one dimension as an example. Go to

https://www.triangle-calculator.com/. there are several formulas that are available to go with different information that you might have. I used Triangle Calculator for this one. Each time you calculate you get a picture so you know if you did it wrong.

Mount your piece in the lathe, concentric, TIR etc. Put a piece of square stock in tool holder, insert next to angle and dial compound/crosslide until it is the same angle. Switch to test indicator and run back and forth on angle. Adjust crosslide for 0 deflection on gauge just like doing a taper. Read crosslide and plug in degrees in formula. Done! Down and dirty, easest and quickest.

Alternate. Use test indicator like an edge finder. touch inside front edge, back out and at point it changes, set 0 on leadscrew. Advance inside and do the same. At point reading changes, read numbers on dial. Account for backlash.

*** Important!*** you have to look at how the dial indicator is touching. If you take readings off of center high point, your good. If you use the side/thickness of ball add 1/2 diameter just like an edge finder.

You said you have a chamfer inside edge. Your options are to guess. Ignore it. Get really fine readings with the test indicator and do the math. Or take a cast and use dial indicators, feeler gauges and small drill bits and really good eyeballs to increase the accuracy of your readings.

Don't know about green metrology wax, but I do know about lost wax casting jewelry. You can buy the wax to make ring and jewelry patterns, but you don't need that much, got an oz from a jeweler who makes his own. Make an aluminum foil dish or cupcake sided holder. Turn on oven to 350 and put inside. Check every few seconds until it looks liquid. The wax melts between 150 -350 degrees depending on brand and properties.

Prepare the piece. Spray cooking oil on area. PAM or something like it. You want to pour the wax so you have a narrow width and a thick vertical piece. Make a trough front to back with anything that you can and pour wax. Let cool to room temperature and remove by rocking side to side, not by prying up. The wax can be filed, drilled, built upand measured to determine/adjust chamfer or edge rounding. Again, take into account thickness, diameter or distance and adjust calculations. If you really try hard, you can get down to 1-2 thousands in your calculations.

Sorry about the length. All the answers above were right and I have used all of them depending on what was easier at the time. Good Luck!

Charles