Does anyone have the Spindle-to-pivot distance for a Shure M232 12" arm?

I don't know how accurate I will be if I try to measure it myself.

and how does one make a seperate armboard for a tt?

Any suggestions?

I am about to mount the 232 on a Miracord XS-200 that I removed the autoguts from.

should I just try to screw a piece of wood into the metal base of the Miracord? Using angle brackets or somesuch?

Or should I do something else?

I kinda destroyed the Miracord arm getting it off, anf the manual says that it does not like to track under 6 grams anyways....so.....

tl;dr:

How do I make an armboard and screw into metal?

What's the spindle to pivot distance of a Shure M232?

David, it's possible someone else will have this information, but until then, I'll try to make some suggestions. I had no idea what this turntable or tonearm was, so I found some pics on ebay. For those keeping score, the player is from the 50s and the arm is from the 60s. For this, I think you're going to just have to use some ingenuity. I'd just drill some holes and use nuts and bolts to mount a piece of wood.

Did you do any checking to see if the existing mounting of the cartridge conforms to either Baerwald or Stevenson geometry? If you can't, it's not critical, I'm just curious.

For this, you'll have to do your own measuring. If you can do it in metric so much the better, otherwise it's fine and I'll just convert.

1. What is the pivot-spindle distance of the Miracord arm?

2. What is the pivot-stylus distance of the Miracord arm as it is with the cartridge currently mounted? This is the straight line distance disregarding the bend in the arm.

3. In the Shure arm, can the cartridge be shifted forward and backward or is it forced to be at one place? Mount a cart on the Shure arm keeping it parallel with the head. If shiftable, measure the range of pivot-stylus distances by pushing the cart all the way in, and then bringing it all the way out. If not shiftable, just measure the fixed distance.

4. Can the cartridge postition be rotated inward or outward or must it stay parallel with the head?

5. Do you have a regular geometry protractor to measure the angle the head makes with the long axis of the arm? If so, just get as close as you can.

Now that you went through all this, someone will most certainly have the numbers. :D But if not, I'll try to calculate something for you.

David, it's possible someone else will have this information, but until then, I'll try to make some suggestions. I had no idea what this turntable or tonearm was, so I found some pics on ebay. For those keeping score, the player is from the 50s and the arm is from the 60s. For this, I think you're going to just have to use some ingenuity. I'd just drill some holes and use nuts and bolts to mount a piece of wood.

Did you do any checking to see if the existing mounting of the cartridge conforms to either Baerwald or Stevenson geometry? If you can't, it's not critical, I'm just curious.

For this, you'll have to do your own measuring. If you can do it in metric so much the better, otherwise it's fine and I'll just convert.

1. What is the pivot-spindle distance of the Miracord arm?

2. What is the pivot-stylus distance of the Miracord arm as it is with the cartridge currently mounted? This is the straight line distance disregarding the bend in the arm.

3. In the Shure arm, can the cartridge be shifted forward and backward or is it forced to be at one place? Mount a cart on the Shure arm keeping it parallel with the head. If shiftable, measure the range of pivot-stylus distances by pushing the cart all the way in, and then bringing it all the way out. If not shiftable, just measure the fixed distance.

4. Can the cartridge postition be rotated inward or outward or must it stay parallel with the head?

5. Do you have a regular geometry protractor to measure the angle the head makes with the long axis of the arm? If so, just get as close as you can.

Now that you went through all this, someone will most certainly have the numbers. :D But if not, I'll try to calculate something for you.

The Original arm seemed to have a useful lenghof soemthing like 8".....something much shorter than my TEchnics SL-D202....which I assume to have a 9" useful length....

I destroyed the Elac arm getting the auto mechanism out (I THINK idestroyed it, but I would have to make a new base and rotator for it to work....the old one was part of the auto-mechanism.....)

The Shure can have an adjustable cart, but I do not remember if it is able to rotate or not.....IIRC the range of adjustmentis about 1" back and forth...

And the cartridge mounging slide has 2 sets of mount-holes....seperated by about 3/4".....

The folder that it miracord came with had some reviews with it, and one of them mentioned a 2degree tracking angle accoracy (whatever that means), so I'll go back and check it out and see what it says......

This sounds like a fun project....building a turntable out of free stuff....everything free except the arm mounting hardware, and I'll see if I can scrounge some of that...and I have the drill bits and the drill...I am just interested in what I can so for so little money....

AND....it came with a working Shure M93 cartridge with good stylus, so I even have a good cart to mount on it.....and if that's too new, and if can get a new stylus for a Shure M3D, I have an M3D around that I can mount....

AND....I have a Russco phono preamp that came with my Russco CueMaster (where I am pulling the arm from) that M mounted on a board....I'll put this under the base of the Miracord and make the outputs Line Outs....then I can use my new(to me) Pioneer QL-600A as a basement stereo....

Okay, since you can't give me exact measurements and this is just a fun project, do this. Measure the Shure arm's usable length--to about the midpoint of where the stylus would be. Subtract 5/8" to 3/4". That's your pivot to spindle distance.

Okay, since you can't give me exact measurements and this is just a fun project, do this. Measure the Shure arm's usable length--to about the midpoint of where the stylus would be. Subtract 5/8" to 3/4". That's your pivot to spindle distance.

Will be done when I get home from summer school :yes:

Hi David,

Chances are that the mounting distance is “232mm” which sounds about right for a 12” tonearm. A quick double check would be to measure the distance between the stylus and the pivot with the cart mounted in the middle of its “throw” in the headshell. This measurement probably will come out to 232 + 10 to 20 mm for a ballpark overhang.

If the Miracord previously hosted an 8” or 9” tonearm, you might find that you can mount the arm off the topplate. When making an armboard, don’t forget about VTA. You’ll want to eyeball the best height for the armboard in relation to the platter so that you’re within range of the tonearm’s VTA adjustments (if any).

Got any pictures of your predicament … er project?

All best,
Mario

Hi David,

Chances are that the mounting distance is “232mm” which sounds about right for a 12” tonearm. A quick double check would be to measure the distance between the stylus and the pivot with the cart mounted in the middle of its “throw” in the headshell. This measurement probably will come out to 232 + 10 to 20 mm for a ballpark overhang.

If the Miracord previously hosted an 8” or 9” tonearm, you might find that you can mount the arm off the topplate. When making an armboard, don’t forget about VTA. You’ll want to eyeball the best height for the armboard in relation to the platter so that you’re within range of the tonearm’s VTA adjustments (if any).

Got any pictures of your predicament … er project?

All best,
Mario
Mario, your post brought to my attention something that I missed--that this is a 12" arm. But I think with 232mm you're thinking of a 9" arm. 12"=305mm. According to my arm spreadsheet, given that effective length, mounting distance (pivot-spindle) is 291.5mm, and offset angle is 16 degrees, resulting in the Baerwald null points. Checking the measurements at vinylengine.com for the SME312 arm, this is in the ballpark. But, as you recommended, a more accurate pivot to stylus measurement will enable honing down the actual mounting distance.

Mario, your post brought to my attention something that I missed--that this is a 12" arm. But I think with 232mm you're thinking of a 9" arm. 12"=305mm. According to my arm spreadsheet, given that effective length, mounting distance (pivot-spindle) is 291.5mm, and offset angle is 16 degrees, resulting in the Baerwald null points. Checking the measurements at vinylengine.com for the SME312 arm, this is in the ballpark. But, as you recommended, a more accurate pivot to stylus measurement will enable honing down the actual mounting distance.

Yeah, Howard you could well be right. I guess 12" overall can be a catchall for a lot of 10" or 11" arms. Usually an imbedded three digit number in the tonearm's name - Ortofon AS-212 etc. points to the mounting distance - but this may or may not be the case here.
But you're right to catch me on my slip about broadbrushing 12" arms.
- Mario

Yeah, Howard you could well be right. I guess 12" overall can be a catchall for a lot of 10" or 11" arms. Usually an imbedded three digit number in the tonearm's name - Ortofon AS-212 etc. points to the mounting distance - but this may or may not be the case here.
But you're right to catch me on my slip about broadbrushing 12" arms.
- Mario
Didn't even think about the 232 in the name, but now I see what you mean. :yes:

I kinda destroyed the Miracord arm getting it off, ....

...I destroyed the Elac arm getting the auto mechanism out (I THINK idestroyed it, but I would have to make a new base and rotator for it to work....the old one was part of the auto-mechanism.....)

David, I guess this is water over the bridge, spilled (spilt for you Brits) milk, etc... and you've probably thought this already, but PLEASE, next time you run across something that looks a little tricky or might turn out to result in irreversible damage to something like a tonearm which has survived 50 years or so without your intervention, PLEASE stop and ask for help. I'm sure it wasn't necessary to damage/destroy that tonearm, in order to remove it. So it might not have been a high-end audiophile thing, but some collector of vintage might have loved to have it, undamaged, to complete a restoration project. I don't mean to be harsh; it probably wasn't deliberate and we have all screwed stuff up at one time or another. Just a friendly reminder that there was a lesson to be learned here.


[QUOTE]This sounds like a fun project....building a turntable out of free stuff....everything free except the arm mounting hardware, and I'll see if I can scrounge some of that...and I have the drill bits and the drill...I am just interested in what I can so for so little money....[QUOTE]

While it hurts to read about busted vintage tonearms, I do think it's GREAT to build a TT from free and scavenged stuff! Lots of fun to be had and stuff to be learned, and you may surprise yourself with the quality of sound that results. Good luck! :thmbsp:

Hi David,

If the Miracord previously hosted an 8” or 9” tonearm, you might find that you can mount the arm off the topplate. When making an armboard, don’t forget about VTA. You’ll want to eyeball the best height for the armboard in relation to the platter so that you’re within range of the tonearm’s VTA adjustments (if any).

Got any pictures of your predicament … er project?

All best,
Mario

I intend to make a seperate arm-board and mount it to the base of the Miracord, not the top-plate, which is spring-loaded and would probably be off-balance with a big piece of wood with an arm on it mounted to the side...

I think that I am going to use 2x4 for this, instead of 1x4 which I have), or maybe even plywood sandwiched together, so i can get enough height out of the armboard to allow me to mount it to the base and still have decent VTA. I'd rather the VTA be a little low and I can raise it than a little high...

And pix forthcoming. I shoulda taken some during the tear-down, but I was not thinking......

David, I guess this is water over the bridge, spilled (spilt for you Brits) milk, etc... and you've probably thought this already, but PLEASE, next time you run across something that looks a little tricky or might turn out to result in irreversible damage to something like a tonearm which has survived 50 years or so without your intervention, PLEASE stop and ask for help. I'm sure it wasn't necessary to damage/destroy that tonearm, in order to remove it. So it might not have been a high-end audiophile thing, but some collector of vintage might have loved to have it, undamaged, to complete a restoration project. I don't mean to be harsh; it probably wasn't deliberate and we have all screwed stuff up at one time or another. Just a friendly reminder that there was a lesson to be learned here.

While it hurts to read about busted vintage tonearms, I do think it's GREAT to build a TT from free and scavenged stuff! Lots of fun to be had and stuff to be learned, and you may surprise yourself with the quality of sound that results. Good luck! :thmbsp:

Yea....I regretted that as soon as I got it off....I still have the parts, but I doubt that I could get the whole arm assembly back together again.....

....and I I have another use for the arm.

HANG IT ON MY WALL!!!!

I think that a TT arm hanging on my wall would be a seriously cool decoration, especially for someone like me....


Also, I am going to re-mount the buttons and try to make it look as stock as I can, and glue the start/stop buttons together to make one button and make them function....unless I do it with the old arm-post....

I also got Michael Fremer interested in this project....:D:D:D

I intend to make a seperate arm-board and mount it to the base of the Miracord, not the top-plate, which is spring-loaded and would probably be off-balance with a big piece of wood with an arm on it mounted to the side...

I think that I am going to use 2x4 for this, instead of 1x4 which I have), or maybe even plywood sandwiched together, so i can get enough height out of the armboard to allow me to mount it to the base and still have decent VTA. I'd rather the VTA be a little low and I can raise it than a little high...

And pix forthcoming. I shoulda taken some during the tear-down, but I was not thinking......


I don't think I would use a 2 x 4 for this project, I think it is going to be clunky and the wood itself is very soft. Your idea of going with laminated ply sounds like the better alternative and in my opinion result in a nicer finished product. Pictures would really help get a better handle on exactly what you are trying to accomplish with this project.

My advice to would be to make every thing that you change or add reversible, that is if in the future you want to do something with this table again you can. This is a learning project for you and a great one at that.

OK...just got the response from Shure (I emailed them about the arm, it was a LONG shot....but....) They sent me the user manual, and here are the specs.....

Length: 322mm
Base Diameter: 68.3mm
Range of height adjustment: 57.2mm
Spindle to Pivot distance: 210mm

Ok....so what does all of this mean? I have NO IDEA...

Pix are uploading, but i do think that I have found a way to re-mount the original arm of this....provided I find a way to mount the assembly with the parts I have on hand....and surprisingly, i did NOT break it. :D. I'll have to re-wire it (probably a good thing), but nothing is broken, on the arm itself....I just have to screw it back into the remaining parts to the mechanism. I have the original bearing system, and if I can find some way to mount it, I certainly will.

Spindle to pivot is your mount distance. This thing has he effective length of a Linn.
Sounds like an huge base - but this is probably not the stub size - we'll await pictures - otherwise we're shooting in the dark here.
- Mario

Sorry about the pix..I fell asleep..AND I uploaded the wrong ones. *facepalm*

Uploading the correct ones now...
The miracord as it stands now:
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000839.jpg


Underside:
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000839_02.jpg


The arm assembly: (original)
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000839-2.jpg
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000840.jpg
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000841.jpg
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000842.jpg


The Shure M232 arm
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000845.jpg


The Phono preamp:
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000847.jpg
http://i267.photobucket.com/albums/ii298/vinyldavid/IM000848.jpg


OK...there ya go....

OK....I can hear the platter turn on the main bearing when my ear is close.....so....will 3 in 1 oil work to lube the main bearing if applied with moderation?

You know it looks like you could build a whole new plinth and just mount the motor and spindle on it. Something massive would help. It would probably be a lot more work but would take care of a lot of problems. The spring suspension on the original plinth is going to be useless once you mount any kind of arm board.

You know it looks like you could build a whole new plinth and just mount the motor and spindle on it. Something massive would help. It would probably be a lot more work but would take care of a lot of problems. The spring suspension on the original plinth is going to be useless once you mount any kind of arm board.

That will probably come next, and the way thatI am going to mount the arm-board is to screw it into the metal side of the base of the turntable, and just have the arm aligned vertically with the platter....


WhenI get some plywood (more of it), I'll try that....but I am going over to a friend's house tomorrow, and he usually has some plywood lying around....that would certainly make things MUCH easier......:scratch2:

The only difficult task would be to re-mount the idler assembly....along with the control system....:scratch2:

I'll have a look at it when I get home and assess it's feasability....

Also, would it be too much mass added to the arm if I cglued some stiff wire to the existing arm lift thingie on the headshell? I seem to have a problem cueing it accurately with my big fingers using just that little protrusion...

David I am not sure of your ultimate goal with this project is. I think it is great that you are trying to figure out how to do all this. Are you doing it the way I would? No. Are you taking on a worthy project that you will learn from? Yes.

As far as the project goes, I think you should just go for it and chalk this one up as a learning experiment. I can guarantee you will run into some problems but that does not mean you can't resolve them. Some of my greatest inspirations have been born from my biggest disapointments.

I am not sure of how good of a woodworker you are but if your skills are not great in this area it may be a good time to make friends with someone who can teach you some new skills. Does your school have a shop?

As far as the bearing goes: I would first clean everything before adding oil.

Adding weight to the headshell: If it is not going to affect the tracking force I guess you can do whatever you want.

David I am not sure of your ultimate goal with this project is. I think it is great that you are trying to figure out how to do all this. Are you doing it the way I would? No. Are you taking on a worthy project that you will learn from? Yes.

As far as the project goes, I think you should just go for it and chalk this one up as a learning experiment. I can guarantee you will run into some problems but that does not mean you can't resolve them. Some of my greatest inspirations have been born from my biggest disapointments.

I am not sure of how good of a woodworker you are but if your skills are not great in this area it may be a good time to make friends with someone who can teach you some new skills. Does your school have a shop?

As far as the bearing goes: I would first clean everything before adding oil.

Adding weight to the headshell: If it is not going to affect the tracking force I guess you can do whatever you want.

Iam a pretty good wood worker....I think that I will go your route and mountthe whole theing on some scrap plywood......itmakes a LOT more sense, and is a lot easier to upgrade.. and make quieter...and add more mass to....

I'll take the measurements tonight and see what wood I canget for free (I'd buy somebut my goal is to do this for FREE).

I have a hand drill and some drill bits, and my friend has a power drill and some spade bits for the bigger holes.....I'll see what i can cook up. And I can transfer the nameplate to the new plinth.

ThisreallyIS goingtobe a fun project.....I think that I'll style the plinth after the TT's that I have seen that have a plinth that is a ltitle bigger than that platter and round, and then goes into a small piece for the arm. In teh Style of THe Funk Firm TT's...just in ply.....