Hi friends,
Is it possible to use pure iron to replace sae1010 or 1008? Theorlly the pure iron>99.85% is good for field coil motor. Thanks!
Is it possible to use pure iron to replace sae1010 or 1008? Theorlly the pure iron>99.85% is good for field coil motor. Thanks!
Hi,
Not sure what you mean by pure iron, but the higher the iron content in the alloy the better as long as it is sturdy enough as it get to be a heavy structure.
Not sure what you mean by pure iron, but the higher the iron content in the alloy the better as long as it is sturdy enough as it get to be a heavy structure.
Hi Hentai,
thanks for your reply!
just as you said the higher iron content in the alloy the better. some material like the link below:
http://www.pctmg.nl/uploads/API-Brochure.pdf
i'm very interesting in your field coil project and many thanks you for sharing so many professional experience.
jason
thanks for your reply!
just as you said the higher iron content in the alloy the better. some material like the link below:
http://www.pctmg.nl/uploads/API-Brochure.pdf
i'm very interesting in your field coil project and many thanks you for sharing so many professional experience.
jason
Hi Jason,
The material in your link seems quite good. It has a Brinell hardness close to other low carbon steels so you should be able to machine it in similar fashion.
The material in your link seems quite good. It has a Brinell hardness close to other low carbon steels so you should be able to machine it in similar fashion.
Hi Hentai,
thanks for your confirmation of the material.
i 'm planing a 15" driver want to use field coil motor. but i don't know how to use FEMM to simulate. so i have to spend time to learn this thread from beginning first.
basically for the material and the structure of the motor i have two questions:
1. do i need lathe all the parts of field coil motor by the material i linked above? or i just need to lathe the pole piece to reduce the total cost? (the above material is more expensive than SAE1008 or SAE1010 steel)
2. from your design i can see the copper coil sealed in a sae1010 material can. because i need a more powerful motor to drive a 15" cone. maybe the current is over 3A. so is the open frame better for the heat radiation? (the driver will be installed in a bass reflex box). the picture is my thinking.
thanks in advance for your kind help!
Jason
thanks for your confirmation of the material.
i 'm planing a 15" driver want to use field coil motor. but i don't know how to use FEMM to simulate. so i have to spend time to learn this thread from beginning first.
basically for the material and the structure of the motor i have two questions:
1. do i need lathe all the parts of field coil motor by the material i linked above? or i just need to lathe the pole piece to reduce the total cost? (the above material is more expensive than SAE1008 or SAE1010 steel)
2. from your design i can see the copper coil sealed in a sae1010 material can. because i need a more powerful motor to drive a 15" cone. maybe the current is over 3A. so is the open frame better for the heat radiation? (the driver will be installed in a bass reflex box). the picture is my thinking.
thanks in advance for your kind help!
Jason
Attachments
Hi Jason,
You don't need to use that Armco for all parts, just around the magnetic gap. You can use 1010 for the rest.
Open frame is better for heat radiation.
Please refer to an article i wrote a while back about how to size your parts:
PROJECT RYU Sizing Steel Parts for Field Coil Loudspeaker Motors
What voice coil diameter you have in mind?
You don't need to use that Armco for all parts, just around the magnetic gap. You can use 1010 for the rest.
Open frame is better for heat radiation.
Please refer to an article i wrote a while back about how to size your parts:
PROJECT RYU Sizing Steel Parts for Field Coil Loudspeaker Motors
What voice coil diameter you have in mind?
Forgot to mention about FEMM, I have some scripts that will automate most of the simulation for you. All you need to do is to go in FEMM and import the .lua file and input your parameters. You should get a basic design afterwards.
You can get the scripts from here:
https://github.com/Taur-Tech/Project-Ryu---Loudspeaker-Drivers/tree/master/FEMM_Scripts
You can get the scripts from here:
https://github.com/Taur-Tech/Project-Ryu---Loudspeaker-Drivers/tree/master/FEMM_Scripts
WOW！you have done a great work! It seems a simple work to design a field coil motor. Many thanks for your sharing.
I will use a Altec 416 voice coil with 76.2mm inner diameter. 15" paper cone, the weight of voice coil+cone+cloth foam is about 50g. The reason I choose Altec 416 is that the parts and technical information are very easy to get from the web.
I am in hurry to download your script and FEMM to study. Haha! There must be more questions. I hope that would not disturb you a lot.
Thanks again!
I will use a Altec 416 voice coil with 76.2mm inner diameter. 15" paper cone, the weight of voice coil+cone+cloth foam is about 50g. The reason I choose Altec 416 is that the parts and technical information are very easy to get from the web.
I am in hurry to download your script and FEMM to study. Haha! There must be more questions. I hope that would not disturb you a lot.
Thanks again!
Hi Hentai,
i just downloaded your script and FEMM 4.2. after i run the script and input parameters there is a error message. it means there is no default block material. i don't know where i can setup the default block material or has to setup that in script? please see the pictures.
thanks!
Jason
i just downloaded your script and FEMM 4.2. after i run the script and input parameters there is a error message. it means there is no default block material. i don't know where i can setup the default block material or has to setup that in script? please see the pictures.
thanks!
Jason
Attachments
Hi Jason,
Sorry for long absence. I usually get an email when someone posts. Must've missed it.
Looks like an error in geometry of the motor, I will check later today to see if there is an error in the script.
Sorry for long absence. I usually get an email when someone posts. Must've missed it.
Looks like an error in geometry of the motor, I will check later today to see if there is an error in the script.
I uploaded drawings for a new motor, F144. It will fit a 31mm voice coil, so this time a smaller voice coil for lower weight and for higher frequency extension.
Will start soon winding the fieldcoil and will update the project with fieldcoil data.
You can get 2D and 3D files at the link below:
https://github.com/Taur-Tech/Project-Ryu---Loudspeaker-Drivers/tree/master/Drivers/F144
Some pics of machined F144 pole pieces. Very exciting!
Will start soon winding the fieldcoil and will update the project with fieldcoil data.
You can get 2D and 3D files at the link below:
https://github.com/Taur-Tech/Project-Ryu---Loudspeaker-Drivers/tree/master/Drivers/F144
Some pics of machined F144 pole pieces. Very exciting!
Attachments
Dear Hentai,
In recently, you think which voice coil 31mm is the best for high frequency response ?
Thanks.
In recently, you think which voice coil 31mm is the best for high frequency response ?
Thanks.
Hi,
Not sure what you mean but compared to a 50mm I had before I expect this smaller voice coil will have better high frequency response but sacrificing power handling.
Not sure what you mean but compared to a 50mm I had before I expect this smaller voice coil will have better high frequency response but sacrificing power handling.
Which one is 18 inches ? Very nice driver.
I have also a new field coil project. My planing 18 inches with version " Golden Edition", which will be finished soon on next someday .
Pictures will be shared in here later.
Best Regards,
I have also a new field coil project. My planing 18 inches with version " Golden Edition", which will be finished soon on next someday .
Pictures will be shared in here later.
Best Regards,
Hahaha ghpicard!
Thank you guys. It is a 12" driver still but with a smaller voice coil. I have an initial inductance measurement which is far better than before ~ 0.5mH.
I will return with measurements and with all the details.
Thank you guys. It is a 12" driver still but with a smaller voice coil. I have an initial inductance measurement which is far better than before ~ 0.5mH.
I will return with measurements and with all the details.
Absolutely beautiful work, Hentai, as always - really looking forward to seeing your measurements and results. If you don't mind sharing, I'm likewise curious about the sets of holes around the periphery of the casing, and would love to know what they do for your design.
I took a long break from my project, but now that I'm enjoying a couple of weeks of vacation I've gotten back to it. I've made my first voice coils, and as a first try I'm reasonably pleased with them. They're about 8.7 Ohms, weigh 2 grams each and use a treated Thai mulberry paper for the former. I plan to make a few versions this week with different resistances.
My first effort making a cone came off it's mold a couple of days ago as well. It's made from the same treated mulberry paper. This first one pictured below has a few cosmetic defects, but that's okay - I'll improve on each try. I have another form for the whizzer cone, and plan to have a few sets of cones and whizzers with different mulberry and washi papers in the next couple of weeks. The one below is 7 grams and is quite stiff. Hentai - do you think I should be concerned with that weight, or does it seem light enough? The motor I've made is very similar to what you built for Frank.
Next week, I'll try try making cloth and paper surrounds doped with highly thinned butyl rubber.
I took a long break from my project, but now that I'm enjoying a couple of weeks of vacation I've gotten back to it. I've made my first voice coils, and as a first try I'm reasonably pleased with them. They're about 8.7 Ohms, weigh 2 grams each and use a treated Thai mulberry paper for the former. I plan to make a few versions this week with different resistances.
My first effort making a cone came off it's mold a couple of days ago as well. It's made from the same treated mulberry paper. This first one pictured below has a few cosmetic defects, but that's okay - I'll improve on each try. I have another form for the whizzer cone, and plan to have a few sets of cones and whizzers with different mulberry and washi papers in the next couple of weeks. The one below is 7 grams and is quite stiff. Hentai - do you think I should be concerned with that weight, or does it seem light enough? The motor I've made is very similar to what you built for Frank.
Next week, I'll try try making cloth and paper surrounds doped with highly thinned butyl rubber.
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