[James Dressman] emailed us about his two-year journey of getting a large CNC machine running in his home. He doesn’t currently have a webpage, however his story was so incredible that we just had to feature it. [James] started by doing plenty of research online, and ordering a new CNC. The real fun started when he opened up a wall to fit the 2300 pound monster into his home. [James] found so much insect and water damage that he ended up rebuilding the entire rear half of his home.

Once the CNC was safely set up, the fun still wasn’t over. Not all family members are keen on having an industrial machine tool in the house. In [James’] case it was the smell of way oil that drove his wife nuts. This was all before spindle problems with the tool itself began to rear their ugly head. Illness and family tragedy put everything on hold for several months, however once [James] strength returned, he attacked the problems with renewed vigor. It was a long and winding road, but he now has a fully functional CNC.

But don’t just take our word for it. Continue after the break to see his photo album and to hear James tell the story in his own words.

Hello Hackaday!

Perhaps befitting our proximity to Halloween I offer a nightmarish tale that began in early 2011. With aspirations of design and invention I quickly became discouraged with the lack of resources to inexpensively prototype parts. This frustration mounted and forced me into the direction of trying to figure out how to make things myself. After researching CNC mills and knowing nothing about them or machining in general I took the plunge and bought one brand new fearing my lack of knowledge to build one or buy used. I taught myself everything I could on the internet in the 3 months it took to deliver. Shortly after ordering it I realized I had to tear out a door going from the garage to the basement where it was reside. This act uncovered some dark secrets about the house like termites and rotten supports holding up the floor of the back deck (which was the roof of the garage). This forced me to try and remove the damaged material but the more I uncovered the worse it got until I decided to just completely tear out the existing deck/roof and rebuild it. I also realized that the roof of the house overhanging the garage was in danger of collapse because the garage roof was the load bearing component of the columns holding the house roof up. Essentially what started with moving the machine into the basement resulted in me ripping off the entire backside of the house and rebuilding it. When it got here I had to tear out the wall and the door and later replace them to get it inside. That was a good all nighter just to move it inside (this machine weighs in at around 2300lbs).

Once it was in the basement I began trying to use it. First my wife couldn’t stand the smell of the way oil and I was forced to use it only when she wasn’t home and only with the windows open. The noise also became a major issue as there are air ducts that go from directly over the machine all the way to the top floor right to her side of the bed. I was initially practicing in wood but when I moved on to metal the demon in the machine started to emerge.

I noticed that the spindle seemed to have almost no power and often, strike that, always stalled causing me to break or chip my expensive carbide endmills. I went around and around with the manufacturer. They blamed me, my residential power, the electricians, the soil conductivity for my ground line, the ionosphere, everything but themselves. I had electricians, engineers, CNC repair technicians, everybody you could think of to either come over and look at it, conduct tests, or consult over the phone. I spent hundreds if not thousands just to try and find a fix. They all said the spindle drive electronics were the problem. The manufacturer denied all allegations. Around and around we went for years. There is sat in my basement a barely usable paperweight that was completely unsuitable for cutting metal.

Having nowhere to go I would occasionally get the bug and research aggressively for a week or so for some kind of fix but I would soon realize it was way beyond my capabilities to fix and there were no easy answers. I resorted to fix trivial things that were within my grasp like designing and cutting a clear Lexan top enclosure to keep the coolant spray in the machine instead of all over the walls and the computer monitor…in the event I could ever use it.

Time went on, I had a child, then I got sick. I spent 6 miserable months on chemo and finished on Thanksgiving day of last year. A couple of weeks later, still feeling like death warmed over, I got drop kicked in the nuts. We discovered our 12 month old had a rare and aggressive cancer and following a major surgery he spend a few months on chemo. I’m happy to report he is doing just fine now. Shortly after he finished his treatments I was informed that I was being laid off.

So there we were, sick, huge medical bills (even with insurance), and unemployment. This is not a sob story though because I decided I was going to strangle every drop of life out of this machine and make it work.

I refocused my resolve and began researching everything I could about spindle motor technology and soon decided on one. Knowing very little about electronics or how to implement it but yet knowing that others have done it and succeeded I decided to replace all of the spindle drive electronics as well as the motor. Doing so would require knowledge of all the proprietary interfaces to the existing machine electronics, so with no input or communication from the manufacturer I began reverse engineering all of the existing components with a multimeter to determine what signals did what and how. I read everything I could about electricity and circuitry over the past few months, took measurements to see what type and size motor would fit, what drive to control the motor, and what signals each accepted and generated.

I built a circuit on a breadboard I bought from radio shack to test the proof of concept and with each small thing that worked I would realize that “oh hey I also need to do this, and that, and that, and that, and oh yeah that too.” The circuit started growing in capability. At some point I just decided to make the circuit do everything the old set up did to be a seamless transition as well as some added capabilities. The motor drive I chose was a VFD which famously produces huge amount of electrical noise and consequently this blasted my circuit. I had to borrow an oscilloscope from a friend and get some professional consultation to overcome that problem but was ultimately successful. I rebuilt the circuit a number of times when I thought of a way to make it simpler or neater or more elegant. I’m going to use it for awhile in breadboard format to make sure it all all works like it should then I intend to have a circuit board printed so i can offer it to virtually every other user of this machine whose spindle motor and drive are to put it bluntly, crap.

In the meantime; concerned about the noise and smell I originally was going to build a room around it in the basement and soundproof it, but later decided to move it to the garage. This would require installing a garage door, running electricity to it, insulating it, and climate controlling it, all of which I did this past summer then ripped the door out again and moved it back outside.

The new motor required a custom designed and machined motor mount to fit on the machine, which I very gingerly did using the old motor. Just prior to this I also began having axis motion issues and someone had suggested I use an “smoothstepper” which is an external pulse generator that plugs into the ethernet port. I bought one but then realized that the supplied integrated computer on the mill had the ethernet port caulked shut. After carefully picking out the graciously supplied caulk I then hit another snag, the LAN was disabled in the BIOS permanently. Not only did the manufacturer physically disable the ethernet port, they actually hacked the BIOS to deny that it be used ever. Re-flashing the BIOS had no effect. After some late nights online I found a way to “unhack” it in DOS with a bootable thumb drive and re-enable it. I’ve also replaced some of the axis motor drivers, and the lights, which were all failing.

Perhaps this entry is slightly premature because I have encountered some other ghosts in the machine that I am attempting to exercise before everything is installed and working perfectly. I have done everything piecemeal and got it to work exactly as intended it’s just that now I’m in the home stretch and about to put it all together but have run out of time. Monday I leave town to have surgery, and it involves a rather lengthy recovery so it will have to wait. I got so far just to leave in the final hour, but I’m confident it will work and I will be successful in cleansing whatever curse this beast has brought into our lives. This story is 100% true and if anything is waaaaay under embellished for the sake of brevity. This was years of me banging my head against a wall that also happened to be pissing on me with hot flaming malevolence, a ton of hard work, and more than I ever wanted to know about electrons. It has become a near legendary saga amongst those who know me. Almost literally every step forward resulted in 10 steps back, there were times where I was afraid to do anything for what it might unleash. It has solidified my belief that the universe is alive…and it is pissed off. At least I got my reverse engineering degree out of it and the bottom line is that I will now have a reliable and powerful spindle instead of the jokey tool breaker that was in there before.

Here is the forum where I detailed many of my efforts, my name is SWATH:

http://www.cnczone.com/forums/mikinimech/

I’ve also documented many of the issues and fixes on my You tube channel here :

http://www.youtube.com/channel/UCGZPaStGbEBZw3QcAgtORVQ