Making a Solenoid ??

[[email protected]]

Hi folks,
Pardon me for barging in and jumping in with a question but I need to
make a bunch (73) of solenoids for an organ conversion project that I
am into.

Here are the design requirements:
diameter of solenoid .75"
Length -- 2 to 3"
Piston -- .25"
Piston throw -- .375 - .5 "
Piston force about 8 oz.
Stroke type -- Push
supply voltage 12-24 vdc
supply current -- whatever is needed

I have found that I can make some bobbins that are a perfect size from
Bic ballpoint shafts and nylon washers for the ends so that would give
me an inside diameter of the coil of just a shade over .25"

Now the question: Could someone point to where I might find a web
resource page where I can find the neccessary information as to the
best wire gauge to use and then number of turns I should use? A
pointer to an .xls spreadsheet would be *great*!

Or a web page where solenoid design is discussed would also be
wonderful.

Many thanks in advance
Bill

BTW, I am converting an old reed organ to MIDI control and these
solenoids will control the opening of the valves of the organ.
Thanks again

 

[Ignoramus27636]

I was looking for a solenoid 1.5 years ago (for fuel shutoff on my 26
years old Onan diesel generator), and I learned then that there is a
great multitude of solenoids available, and that companies could
custom make them also. I would look into buying them, at your
quantity.

i

 

[Sven Wilhelmsson]

Hi folks,

Now the question: Could someone point to where I might find a web
resource page where I can find the neccessary information as to the
best wire gauge to use and then number of turns I should use?

To get a magnetic B-field of 1 Tesla over an airgap of 1mm,
about 1000 Ampere-turns is needed. Proportional to the airgap.
The magnetic force is ~50 N/cm2 if you have one Tesla, it goes as B-squared.
Iron saturates at ~ 2 Tesla.
Have the coil as close to the airgap as possible, because magnetic flux
wants to leak.

 

[Rich Grise]

Hi folks,
Pardon me for barging in and jumping in with a question but I need to
make a bunch (73) of solenoids for an organ conversion project that I
am into.

Here are the design requirements:
diameter of solenoid .75"
Length -- 2 to 3"
Piston -- .25"
Piston throw -- .375 - .5 "
Piston force about 8 oz.
Stroke type -- Push
supply voltage 12-24 vdc
supply current -- whatever is needed

Find a pinball machine seller/servicer/owner/operator, and look at drop
target reset solenoids. I once had a pie-in-the-sky dream about mounting
88 of them on a piano, but at $8.00 apiece that got back-burnered in a
hurry. ;-)

(I used to repair pinballs, video games, jukeboxes, and so on. It was
a pretty neat job - after work, we could all go into the showroom and
play the games for free. During my interview, I said, "I'm gonna be
honest - I like video games, and after one's fixed, it has to be tested,
right? " )

Good Luck!
Rich

 

[Bob Eld]

Hi folks,
Pardon me for barging in and jumping in with a question but I need to
make a bunch (73) of solenoids for an organ conversion project that I
am into.

Here are the design requirements:
diameter of solenoid .75"
Length -- 2 to 3"
Piston -- .25"
Piston throw -- .375 - .5 "
Piston force about 8 oz.
Stroke type -- Push
supply voltage 12-24 vdc
supply current -- whatever is needed

I have found that I can make some bobbins that are a perfect size from
Bic ballpoint shafts and nylon washers for the ends so that would give
me an inside diameter of the coil of just a shade over .25"

Now the question: Could someone point to where I might find a web
resource page where I can find the neccessary information as to the
best wire gauge to use and then number of turns I should use? A
pointer to an .xls spreadsheet would be *great*!

Or a web page where solenoid design is discussed would also be
wonderful.

Many thanks in advance
Bill

BTW, I am converting an old reed organ to MIDI control and these
solenoids will control the opening of the valves of the organ.
Thanks again

Why do you need 8 Oz of force over 3/8 inch travel to operate the pallets of
a reed organ? It sounds like you are trying to depress the keys directly
rather than the internal valves. You'll find that you have specified a
robust solenoid that will "eat" lots of power. The force equation for a
magnet in terms of the amp-turns required is: NI = lg(2*F/(uo*Ae))^1/2.
Where NI = amp turns, lg = length of the air gap in meters, F is the
required force in newtons, uo is permeability of space, 4*Pi*10^-7, and Ae
is the pole area in meters squared. I'll leave it up to you to figure out
how many amp-turns you need. It's a lot.

You might be better off purchasing direct pipe organ valve magnets which can
sometimes be had for a dollar or two apiece, used. These things have a built
on pallet and look like a relay. They open about 1/8 of an inch or so to
uncover a hole letting air out to sound a pipe. Typically they run on 12
volts and have a resistance of 60 ohms or so. It shouldn't be hard to adapt
them to operate a reed organ. Check ebay under pipe organs, there's pages of
organ parts and junk. E-mail me directly if you want more information, I've
done lots of work with organs and have midi-ized a pipe organ and am working
on another. montassocatyahoodotcom.
Bob

 

[[email protected]]

Thanks much, Bob. But the formula is beyond me. I will contact you
off list.

Thanks again.

Bill
And thanks to everyone else who has offered suggestions and help!!

 

[Glenn Gundlach]

Hi folks,
Pardon me for barging in and jumping in with a question but I need to
make a bunch (73) of solenoids for an organ conversion project that I
am into.

Here are the design requirements:
diameter of solenoid .75"
Length -- 2 to 3"
Piston -- .25"
Piston throw -- .375 - .5 "
Piston force about 8 oz.
Stroke type -- Push
supply voltage 12-24 vdc
supply current -- whatever is needed

I have found that I can make some bobbins that are a perfect size from
Bic ballpoint shafts and nylon washers for the ends so that would give
me an inside diameter of the coil of just a shade over .25"

Now the question: Could someone point to where I might find a web
resource page where I can find the neccessary information as to the
best wire gauge to use and then number of turns I should use? A
pointer to an .xls spreadsheet would be *great*!

Or a web page where solenoid design is discussed would also be
wonderful.

Many thanks in advance
Bill

BTW, I am converting an old reed organ to MIDI control and these
solenoids will control the opening of the valves of the organ.
Thanks again

I built this organ back in '89 - '91 and it is all MIDI. If you need
sime 8051 source code and schematics, let me know.

http://haskey.com/johnh/organ/organ.html

GG