Throw a mill head on there and it'll give a Smithy 3-in-1 a run for it's money...
when he spins the sleeve over that cylinder...
ABET accredited level II machinist - CNC Programmer - Mechanical Engineering Technologist
Rio Grande Inc.
Throw a mill head on there and it'll give a Smithy 3-in-1 a run for it's money...
when i used to make airbearings with professional instruments, we used airbearings to make them. a classic example of ... well then how was the first air bearing made, if you need an air bearing to make an air bearing?
be interesting to see the drift characteristics of that machine. its made on a granite basis, and has little to no temp control. its also a simple stacked slide machine, so hes not doing anything tricky with the layout. i doubt it can hold 1 micron for more than a few minutes working time. in fact, hes using old semi-conductor air bearings (west wind etc?)? mmmmm, a micron is pushing it for those spindles ....
Last edited by cockerpunk; 03-07-2015 at 05:19 PM.
social conservatism: the mortal fear that someone, somewhere, might be having fun.
Most of the accuracy and repeatability ratings for "production" machines (with composite castings, etc) are exactly like you mentioned, it makes them have a defined duty cycle time then a separate cooldown time, otherwise there's no way to hold it. But as with most other machining activities, if you're going to try holding that level of accuracy then the machine itself is only a piece of the puzzle.
The thing with machines like that (and this one in the video) their structure is so weak and susceptible to vibration that you can barely do anything. For grinding it's fine, but forget about turning. The parts have to be made on a different piece of equipment then brought over.
There's some solenoid companies that make spools using the same action. They're lapped within millionths and glide together like it's nothing. The problem with those is always rusty air that corrodes the nice surfaces...eww
oh yeah I know about you, I was mostly just babbling to everybody else
It's funny, people in the lathe turning industry complain constantly about machine "rigidity" and how they want a piece of equipment to be "more rigid". The problem is it's a complete misnomer - what they actually want is something that's vibration-dampening, NOT rigid. If you want a rigid machine then go for one made from solid granite. Then cry about it when the machine cracks in half like a piece of glass.
agreed. sometimes damping at the expense of stiffness is cheaper and easier. things don't actually have to be very rigid for precision work, because the material removed and cutting forces are so low. what they need to be is stable (both force and temp) and straight (after corrections applied). people mistake stiffness for both.
EDIT: you'd be amazed at what some well applied double sided tape has been used for ....
Last edited by cockerpunk; 03-09-2015 at 01:50 PM.
social conservatism: the mortal fear that someone, somewhere, might be having fun.
that stuff holds multimillion dollar factories together! (along with zip ties)