How to make precision hole to receive 6mm ball bearing?

Mikey, you are correct. I don't have a boring head. I like the idea of the Criterion, and will ask you some questions via PM.

john
 
Upon further consideration, it occurs to me that measuring the hole might be significantly more difficult than producing it. Go with what you have and Loctite.
 
Mrwhoopee, I do have a set of those very nice Starrett hole gauges, but I haven't gptten to that yet.
Have they not worked well for you? They are twitchy.
 
Mrwhoopee, I do have a set of those very nice Starrett hole gauges, but I haven't gptten to that yet.
Have they not worked well for you? They are twitchy.
I also have a set, but I've never had occasion to try to produce a bearing fit with them. On a bearing that small, the window between too loose and too tight is pretty narrow. With a little practice they will probably get you there. If not, there's still Loctite.
 
I finished the machine using the PETG rotor. It works great at 8,000 rpm, 20 ipm feed, 1/2 inch stroke but 8mm cut (sort of a slot).
I want to repace the PETG rotor with one made from 6061, but so far the printed rotor seems pretty durable. I guess I'll run it until it quits.

Amazinng techology. I have the utmost respect for the guys who thought of needle cutting foamboard.
 

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You must have some bit of vibration or oscillation in your wire, since it's ~.5mm in diameter and you are getting an 8mm wide slot. Probably OK as long as it's consistent.
 
You are inducing twist in the wire that is comming out the free end.

Look up steam engines where they have a sliding carriage where the connecting rod to the piston must be sealed in the cylinder.

The opposite side goes to the crankshaft.

This carriage converts the angular motion to pure linear motion.

Your crankshaft is whipping the wire with each revolution, the energy is placed into the wire, almost impossible to get it out.

Your bushing acts as a guide but the energy is still there.

Sent from my SM-G781V using Tapatalk
 
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