Milling Circular Arcs By Cnc

Chevy,
Help me out with your nomenclature:
1. What is "doc"?
2. "ipt" apparently is not "inches per turn" but "inches per flute"?
3. How did you arrive at the .0015 ipt figure for this particular end mill, by trials (experience) or by manufacturer recommendation?
The best ipt is probably dependent on the material; I am using c544 bronze which has a little lead a cuts a lot like brass.
Dave
 
The accuracy of an interpolated arc depends on the machine used, the required accuracy and the speed at which one wishes to finish parts. For the work that you are doing a light linear bearing way mill would be an excellent choice, such as the Haas mini mills. Many modern systems can correct for mechanical inaccuracies via software, this may be a bit above the level of money that you are willing to spend as it may require paying someone to do a ball bar test on it.

The finish is also dependent on the speed at which the components must be produced, when you contemplate the prices on high end machines you are paying for not just accuracy but accuracy, speed, repeatability and a long service life. One may make 10 perfectly acceptable parts per day on a less then ideal machine, doing the same at 10 parts per hour is a different thing all together.

Good Luck, your work looks excellent.
 
Doc, depth of cut
Ipt, inches per tooth
And yes niagara cutter says .0015 ipt feed for the S545 Elite 5fl end mill, it ends up being 17ipm feed rate for a .5 inch 5 flute cutter spinning at 2300 rpm or so.
 
So I'm not sure that ipt is material dependant, rather cutter dependant, what is gonna cause it to rub? Taking to little doc at too high rpm feeding to slow, so you have to figure out your surface feet, of brass or whatever, so your gonna spin that same endmill 4000 rpm and have a ipt still of .0015, but your gonna need to feed I at 40ipm to keep it from rubbing because of the higher rpm of the cutter. These are just guessing examples nothing is tested just giving an idea. Your going to need to test to see what works.
With my 5fl I fed slow.... terrible finish. The more flutes you have the faster you can feed, and need to feed.
Back to the reel parts, I think it's definitely worth a try, I think you will be pleased with the results, you may even be able to make a jig or fixture that will do 4 or 8 parts at a time and still get the desired finish
 
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