Interesting. Just send me the chips when you want to get rid of them 
. Thanks for explaining.
@Henrik_Larsen That is the beauty of it ZERO waste 100% recycling. Are you in Norway or Sweden? I will post videos of the work though 
Iām in Denmark Of course its recycling, the chips could worth more than the finished item. Great if you publish some videos, Iāll be looking forward to see some gold chips flying.
Most home shop builders work backward from most designers and engineers in that the former works to achieve absolute accuracy and repeatably while the latter determines the needed accuracy and builds the equipment to meet or exceed the standard. Donāt get me wrongā¦ I do the same thing, but we usually severely overbuild to gain small sums of additional accuracy, often unneeded and waste money doing it. Nature of the beast
@Bear_U One application is cutting and polishing granite that the next machine is a custom build for that purpose. Reducing the final polishing time by extremely fine cutting is what is needed. The current machine is like a model for that. I have read the best machines are at one micron, I would like to have that.
One micron is 0.00004" (0.00003937") of precision and repeatability? Get ready to pull out your wallet and max everything, because you are about to spend some serious money!
Are you making testing tables with high precision surfaces?
@Bear_U The accuracy is 20 micron at the moment 0.02 mm (less than one thouā) and the micro switches do perform quite well as I was told they would. Serious money yes, the big boys machines at the top of the ladder currently have one micron repeatability and I believe it will be quite possible to bring that sort of accuracy to the small time users like myself. Rotary encoders I have can give me 2400 pulses per mm but there are other issues of a mechanical nature that need resolving. The electrical and software control systems I am using perform much better than the mechanical components. I suppose the machine I am building would be more suitable for jewellers.
Anything is possible; the cost curve usually looks like a hockey stick standing up though
For now 20 microns is more than enough for this Bear and the equipment I have available to mount the guide rails straight enough to get to oneā¦ Good building mate!
@Bear_U Also realizing the exponential costs of building such an accurate machine there is a point at which I must accept the machine. I am just trying to get the most bang for buck.
That being the case Robert, I applaud your goal. I have worked on large platform commercial CNC stone cutting and polishing equipment and the one constant is the dust and water which result from the operation. I realize I may be preaching to the choir, but sealed, non-optical sensors are highly recommended unless you want to clean every one a hundred times a day. For once I like matched hall and magnet positioning sensors; completely encapsulated, dust insensitivity and highly precise in their repeatability. I usually donāt use them because the magnets collect ferrous debris which distorts the magnetic field and changes the perceived location of the head. Unless you are cutting iron bearing stone, the distortion is almost nonexistent on this type of processing equipment.
@Bear_U Stone cutting and polishing is the exact application for one of my machines. Which in my mind requires automatic tool changing. Guess what? I have designed a low cost tool change system for the home user based on magnets. Also I have no machinist experience other than a rudimentary understanding of drill/hole saw rpm to diameter. My Z axis is very strong and reliable and I am modifying the machine as I go along. However there is an abundance of knowledge and experience in these google plus pages and I do read every comment on CNC I can including comments where I need to use google translate. Quite a few people are interested in my machine so I will definitely be building a few of them. Thanks for the encouragement.