07-06-2024, 05:08 PM
Hi, I just started a new ALF prototype, concept-wise similar to Jim's Reverse Lenz Project. I don't want to fill his thread with my build log, despite the similarities, so here it is. Note, I may later add video links, but for now just some construction advice.
I took a fairly big AC motor, the size of a football, I guess former laundry tumbler or washing machine. It has 24 coils. I decided to remove 16 coils (2 out of 3) and work with the 8 remaining core-fingers. Completely removed all copper. Will use much thinner wire, salvaged from cheap old power supply primaries.
Currently removing the core fingers, using a hand saw... If you saw laminated steel blocks, you need to sandwich them in a press, else the laminates will split apart. My sandwich is made out of 4 wooden bars with 4 big screws, squeezing everything together. 2 bars act also as saw-guide, with an aluminum sheet screwed ontop, elevated 0.5mm by washers, so there is a straight slit along the bar, in which the saw blade in guided. Works ok, given the challenge, but it's tricky.
After sawing, you have to sandpaper the cut face finely, so the laminates have no connections anymore (like tiny spikes from the saw). Then maybe cover the cut face in something to prevent rust. A thin layer of superglue might do the trick.
As for the magnets, I will have to remove the zinc coating (eddy currents) and quickly cover it in superglue, cause that pressed NdFeB material detoriates quickly in the air. At least at the very front side. Hopefully the magnet is still stable enough.
Still need some way to secure the magnets in place better. Esp. because, as I removed 2 out of 3 fingers, the magnet will sit on 2 stumps, which is not ideal. However I thought about 8 versus 12 (remove every second) for quite a while, also in context of available magnets. The way I do it now, seems to be promising all in all, with a few trade-offs, such as certain saturation of those stumps, which actually may even be a positive feature (so the coil cannot alter the permanent magnet "serially").
The rotor I am still designing. It's bit tricky to mount bridges. The axis is great, good steel, with bearings, so I'll use that. Just got to remove that "tincan" coil I guess a 3D printer would be helpful. A robust rotor with holes where you can push in the bridges, whether stacks of laminates, or ferrite or something.
I'm also thinking about to make my own pseudo-ferrite, using iron powder and something like epoxy. Although, these have rather low permeability, compared to ferrite. I have to get my hands on Metglas! They say it's like 1000 times more "magnetically conductive" than iron.
So I'll try to keep you updated, but no guarantee given that I will finish this, as black swans come and go.
I took a fairly big AC motor, the size of a football, I guess former laundry tumbler or washing machine. It has 24 coils. I decided to remove 16 coils (2 out of 3) and work with the 8 remaining core-fingers. Completely removed all copper. Will use much thinner wire, salvaged from cheap old power supply primaries.
Currently removing the core fingers, using a hand saw... If you saw laminated steel blocks, you need to sandwich them in a press, else the laminates will split apart. My sandwich is made out of 4 wooden bars with 4 big screws, squeezing everything together. 2 bars act also as saw-guide, with an aluminum sheet screwed ontop, elevated 0.5mm by washers, so there is a straight slit along the bar, in which the saw blade in guided. Works ok, given the challenge, but it's tricky.
After sawing, you have to sandpaper the cut face finely, so the laminates have no connections anymore (like tiny spikes from the saw). Then maybe cover the cut face in something to prevent rust. A thin layer of superglue might do the trick.
As for the magnets, I will have to remove the zinc coating (eddy currents) and quickly cover it in superglue, cause that pressed NdFeB material detoriates quickly in the air. At least at the very front side. Hopefully the magnet is still stable enough.
Still need some way to secure the magnets in place better. Esp. because, as I removed 2 out of 3 fingers, the magnet will sit on 2 stumps, which is not ideal. However I thought about 8 versus 12 (remove every second) for quite a while, also in context of available magnets. The way I do it now, seems to be promising all in all, with a few trade-offs, such as certain saturation of those stumps, which actually may even be a positive feature (so the coil cannot alter the permanent magnet "serially").
The rotor I am still designing. It's bit tricky to mount bridges. The axis is great, good steel, with bearings, so I'll use that. Just got to remove that "tincan" coil I guess a 3D printer would be helpful. A robust rotor with holes where you can push in the bridges, whether stacks of laminates, or ferrite or something.
I'm also thinking about to make my own pseudo-ferrite, using iron powder and something like epoxy. Although, these have rather low permeability, compared to ferrite. I have to get my hands on Metglas! They say it's like 1000 times more "magnetically conductive" than iron.
So I'll try to keep you updated, but no guarantee given that I will finish this, as black swans come and go.
