DerekZahn
09-19-2005, 11:31 PM
I actually started this project a month or so ago, but just now thought it might be fun to document it. So I'll tell the story a bit at a time and maybe by the time the story is done, the mill will be too.
I've had a little sherline mill for about 5 years which I use for various amusements and have a cheap CNC retrofit kit from a long time ago; I have rather abused this mill, and it's showing its age. Recently I thought I'd get something just a LITTLE bigger, so I started out thinking I would get the Harbor Freight Micro-Mill and retrofit it to CNC control. It went on sale, and I ordered it. I also ordered the extended Y travel kit from LittleMachineShop.com (which arrived before the mill itself).
About the same time, I discovered cnc type stuff on ebay and great web sites like CNCZone...
DerekZahn
09-21-2005, 08:27 PM
Right about the same time, I discovered all the great mechanical stuff you can get on Ebay. Unable to resist, I picked up some choice little items. The first picture shows a x and y axis table with 6 inches of travel in each direction, stepper motors already attached. A really nice little gizmo! The second picture is a THK HRW35 bearing block. This thing is pretty massive.
Now, of course, I'm thinking that the new stuff looks a lot better than the Micro-Mill.... The micro-mill is a great buy for the money, but by this time I'm spoiled by ball screws and linear slides....
Third picture is the start of an idea for using the micro-mill frame (with the extended Y kit) as the basis for attaching various unrelated parts...
DerekZahn
09-30-2005, 10:08 PM
After deciding to attach the XY table to the base of the micro-mill, it became apparent that the existing spindle wasn't going to work very well either, so I decided to sketch up a CAD using a sherline spindle instead.
The next step in construction was to take the base and the table from the micro-mill and remove the dovetails so I could mount stuff onto them. Luckily a friend of mine has a mill he lets me use.
mxtras
09-30-2005, 11:09 PM
Oh, this is getting good!
I need some popcorn.... Keep it coming!
Scott
DerekZahn
10-19-2005, 12:35 AM
The next steps involved starting to attach the newly made pieces.
The first picture shows the micro mill table bolted onto the XY thing. The reddish color is not rust, it's some of that red goo that ruins all my t-shirts.
The second picture shows the base with the z axis slide attached and mounting plates for the XY unit and the spindle assembly.
I have also been working a lot on the electronics, including installing a power supply, 3 geckos, a custom CPU board to read encoders, spindle control stuff, and other junk into an old PC case (picture 3). I'm having second thoughts about some of the stepper stuff, though, and may switch to a different setup.
The AVR board can be seen in picture 4. Its purpose is to read and maintain linear encoders on all three axes and (if desired) on each stepper motor.
praetor
10-19-2005, 08:45 PM
Hey DerekZahn nice job and kudo's on the niiice find(s). man, keep us posted. hope you don't mind asking, is the micro mill the same size a sherline mill or is the a sizable difference?
DerekZahn
10-19-2005, 10:44 PM
The micro mill is from Harbor Freight:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47158
It is much bulkier than a sherline and has a slightly larger travel than the sherline mill with a headstock spacer installed. I can't compare their operation though since I tore the poor HF mill apart before doing anything with it.
ZipSnipe
03-03-2006, 07:29 PM
More pics keep it comin , don,t tease us like this..