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eOrbo replication 2 – winding coil

admin — Sun, 05 Sep 2010 07:45:21 +0000

While waiting for the milling machine parts I finished one core. It was wound with a double 0.25 mm wire. I can choose to connect the two windongs in series, parallel or use only one of them. When finished I checked for shorts between the wire and the core. All you need is a multimeter to check that the resistance between the wire and the core is infinite. I happened to use an LCR meter. One lead was connected to the magnet wire and the other to a knife. I used the knife to cut into the edge of the core between the turns of the coil. Make sure the knife does not touch the wire because it will easily cut through the enamel and give a false reading.

Checking the finished coil

Profiler – in the mail

admin — Fri, 03 Sep 2010 16:59:38 +0000

I hoped to receive the parts for the Profiler before the weekend. Now I have received a tracking number and the package is scheduled for delivery Monday 6th.

Profiler – z-axis upgrade

admin — Wed, 01 Sep 2010 05:48:48 +0000

Franklin Industries has confirmed my payment for a new improved Z-axis for my milling machine has been received. They promised to ship it and a new stepper motor this week, although I hope it will be shipped immediately.

eOrbo replication 2 – LDPE

admin — Mon, 30 Aug 2010 18:47:19 +0000

I have tried different methods to ensure the enamel of the magnet wire will not be cut by the sharp edges of the Magamp/Nanoperm cores. The only good method I have come up with is LDPE. In my country disposable shopping bags are made from LDPE. The average shopping bag is 30 -35 micrometers thick, but I tend to use the thickest I can find. I cut a a 4-5 millimeters wide strip and wind it on the core. Each turn overlaps half the previous turn. I don’t know why LDPE works, but it does – every time (knock on wood).

Cores protected by LDPE

In many other countries disposable shopping bags are made from HDPE which is thinner. This is the kind of shopping bag that makes noise when you handle it. I have not tested it, but maybe whatever makes a good shopping bag can be used?

eOrbo replication 2 – 4 sets of cores

admin — Sun, 29 Aug 2010 10:27:01 +0000

Time to start working again. I have prepared four sets of cores to be tested with the rotor I will let the Profiler mill for me. One set is Magnetec Nanoperm cores, two are Metglas Magamp and the last is plain old Ferroxcube ferrite. The cores, except the ferrite cores, have been prepared the following way:

The cores have been removed from the plastic casing and cleaned.
To make the cores stiff I placed them on a table and placed small drops of super glue gel on the side. With a piece of scotch tape on the finger the drops were distributed evenly on the surface. The procedure were repeated on the other side. The thin Magamp cores were treated this way two times on each side.
To protect the very thin and brittle metal the cores were coated with polyurethane floor varnish.

four sets of cores

The most difficult problem with these cores is that the sharp corners will cut through the enamel on the wire and create a short circuit to the core. One step remains before it is safe to wind the coils. More about that next time.

Profiler improvements

admin — Sun, 18 Jul 2010 04:16:45 +0000

I have ordered a new Kress FME 800 spindle motor and mounting kit for the Colinbus Profiler Pro Z-axis. I also ordered a 3mm endmill for plastics. I hope to receive everything from DamenCNC this week. The new z-axis and a stepper motor to replace the broken one will be ordered from Colinbus one week before I travel to Spain again. Then it should arrive a day or two after I arrive there.

eOrbo replication 2 update 12

admin — Tue, 29 Jun 2010 17:39:50 +0000

I have finally received some MAGAMP cores. Two different sizes, 11 cores in all. Can’t say it was easy as it took 6 weeks and several friendly reminders before the seller finally sent them. They will of course be tested in the eOrbo replication, but that project will delayed about 3 months and I will therefore do some other experiments with thee cores in the mean time. It is unlikely I will share these experiments with the public at this time.

eOrbo replication 2 update 11

admin — Wed, 23 Jun 2010 18:41:34 +0000

I found that the stepper motor for the x axis has an internal short to its metal body and this most certainly disturbs the driver circuit. I have contacted Colinbus support for their opinion and expect a reply tomorrow. It usually takes two workdays for them to reply. I hope I finally found the source of my problems and that a new stepper motor will be the fix. However, this will take time and the next window of opportunity to use the milling machine is in September or so I hope. Oh well, there is a lot of other work to be done at home and now I have no excuse not to do some at least some of it.

eOrbo replication 2 update 10

admin — Mon, 21 Jun 2010 06:05:50 +0000

Yesterday I took the machine apart to adjust the x, y and z axes. This is finished and I found that two ball bearings need to be replaced. After assembling the machine again it would not start. This threw me off balance and I needed to find a quiet place for some moments. Eventually I disconnected the three stepper motors from the drivers and reconnected them one at a time. It worked, but I don’t know why. It is an indication that I have an electrical problem somewhere. When the machine was running again I was touching the bare metal of the machine and noticed a tingling sensation in my fingers whenever the x axis was running. (I am extremely sensitive to this and often feel this tingling when touching a wire from a USB port.) It is interesting to note that the random moves always happen on the very same x axis.

eOrbo replication 2 update 9

admin — Sun, 20 Jun 2010 06:12:29 +0000

This is so frustrating. With the new controller the milling machine sometimes has its own mind. Suddenly it moves to a position it should not have moved to and I have to start over. Cutting through 10mm Lexan is done 0.5mm or 1mm at a time and if the random move happens when the cutter is 9mm into the Lexan the cutter grinds to a smoking halt putting a tremendous load on the machine, the spindle motor and the cutter. Now the Z-axis is out of adjustment and the cutter is bent (or maybe it is the spindle motor). In a last attempt I will reinstall the old controller, try to adjust the machine and try again. Time is running out.