Chips

Finally, my first cuts in Aluminum and success.

Cuts were made in the aluminum mentioned in the previous post using a 1/8″ two flute endmill purchased from  drill bit city.  The design was drawn up in CamBam and for some reason I could not get the holes that were in the drawing to port over to EMC.  To continue the process and not fight with the software, the holes were omitted.  In retrospect this was probably lucky, as the holes were the size of the endmill and there is a good chance trying to plunge the endmill straight down through the aluminum would have resulted in a broken bit.

The aluminum block was held down on the machine with super sticky double face tape, that I purchased at Lowes building supply.  It seemed to hold the work very well, so well in fact it was hard to pry the finished piece off the table with a screwdriver.

Initial spindle speed was set at 5000 and feed rate at 10 inches per min, the aluminum would be cut dry and from everything I could find on line this was a good starting point.  It took quite a while to line up the spindle with the work.  The probe worked very well for finding the top, however aligning X and Y meant quite a few trips from the computer to the machine to jog.  I am thinking laser spot for this step and or remote pendant in the future.

As the spindle plunged into the work I could hear it start to cut and then kind of bog down, after that I wasn’t sure if I could hear the spindle motor any more.  It ran like that for a short while, “milling” out the pocket on the hexagon.

Nerves sat in and I stopped the process, raised the spindle and had a look.  Unfortunately the brush blocks all view of the cutter while its working, so, you can’t see chips, or the cutter.  Its good for vacuum and chip removal, but bad for observation.

Inspection showed a very gouged up mess, the cutter tip was still in tact but the spindle speed seemed way off.  Actually, after investigation, what had happened was the spindle motor fuse blew!  The spindle was not running at all and the machine was just gouging the tip around in the aluminum.  Turns out there was a 32V fuse in spindle fuse holder instead of 250V one.  After it was replaced and the spindle speed increased to 12000 everything worked fine.

I kept the cutting path lubricated with a little Zoom Spout oil and it progressed very smoothly.  The bit did not seem to burn or jam, however the plunging sounded fairly rough.  In the future I’ll ramp down into the work, rather then just plunge.  Holes I’ll drill by hand for now, until I figure out more about the process.

For now, I will call it a very happy success!

Heat Sink on the machine table, still held down by tape.

Close up of finished piece.

Finished Piece removed with pencil for scale.

EMC window showing the tool path used to cut out the piece.

Files used for the piece:

CamBam File for the Luxeon Heat Sink

Gcode File for the Luxeon Heat Sink

EDIT:

Here are some shots of the finished heat sink mounted with LED and driver circuit.  Turned out very nice, however I think I will add some slots on the next version so that there is more surface area and it can dissipate more heat.  It does get pretty hot.

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4 Responses to “Chips”

  1. Chuck Noble says:

    Hi… interested in your retrofit….just bought an old model 18 and I’ve been testing it with pretty good results….
    I would also like to get rid of the factory spindles and mount a variable speed 110 router….
    My electronics are all factory as of right now and everything seems functional and accurate but a tad bit noisey… especially the X drive….moans like a cow…lol
    Thanks for your time
    Chuck

  2. ednspace says:

    Yes, sounds like a good find.
    Recently I have been making lots of changes. The Anaheim stepper control in mine got taken out by a shorted stepper. I made a few attempts to repair it before realizing the stepper on the X was bad. The Anaheim has some custom driver chips that are impossible to find now. I am in the process of converting everything over to gecko drives. I have the drives working and the bad stepper replaced. At the same time I am converting everything over to work with a GRBL shield and a raspberry pi. So far so good, its basically working, next step is the homing switches and the probe tip. I have parts of the original manual and some brochures and things I have collected if you are interested. Its a fantastically rigid machine and seems to be full of potential.

  3. Chuck Noble says:

    Ed..do you see a way for me to use the factory steppers and AA drive with a new style mach3 system ??
    I don’t care about the spindles… probably mount a router. thanks

  4. ednspace says:

    I managed to get the AA drive working with Linux EMC but never tried it with Mach. It basically boils down to tracing all the signals back to the parallel port and then setting up your software to work with those. Here is what I came up with eventually…
    http://soulysolar.mudventions.com/?p=21

    I then took an old printer parallel port cable and made a converter cable so the pins on the OZO ended up on the right pins for the computer. I labeled one end OZO and one end Computer.

    Its been a long time since I worked on that but most of relevant info should be on the blog. This was all done before I had the manual for the machine 😉
    Would have saved a ton of time…

    After my AA drive recently died I am switching it all over to gecko drives and a GRBL shield for the Raspi. Its pretty slick. As of yesterday I can power the machine and the Raspi comes up. Its slick. I also now have homing working now that raspi shares common ground with the rest of the machine.

    Today hopefully probing and getting my stepper board mounted.

    Eventually I may get a touch screen for setup but for now its a mouse and a keyboard in the loop…

    Good luck with yours. Use the stock hardware as long as you can but I can tell already the geckos with smooth acceleration are going to be a big help.

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