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McCurdy CH-12

When I got mine, I removed the grommets and just screwed the metal plinth to the heavy wooden "box" that it came with like Lenco owners do with their modified turntables. Perhaps I was just lucky but I heard no rumble through the speakers while playing music. You may want to try it while waiting for your grommets or before, if you have not ordered already.
Have fun with the project.
 
Took a while but the plinth project is starting in earnest. It’s going to be refined a bit for the final stack but this confirms the fit.IMG_2855.jpeg
 
Movin along, slower than I’d like but the workshop has been needing sprucing up, the table saw in particular. Might try pulling a wood idler wheel from the lathe, but she’s gonna need some attention too before I can do a good job.IMG_2867.jpeg
I still need another inch or so for the motor to sit above the surface. Still debating whether to go for Track Audio adjustable points which would get me a fair bit of height.
 
Comin along. I've got a deep trench around the pilot light to keep that area from overheating. Might fill it somewhat at a later date if it turns out to be too much resonant cavity, but I do want to start by having it open. I'm also considering boring a location for a drop weight to do a similar thing to the Nantais Lenco string mod. Might leave that for a later stage though. I do have a small pulley set aside for the job. Gotta say, routerring all this out has proven to be more of an effort than I had anticipated.
IMG_2882.jpeg
 
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Crossed a milestone this session. I can now actually fit the unit through the whole stack. I even did a quick and dirty armboard.IMG_2888.jpeg73747873810__9C19611A-675A-4CE7-A783-54CEF3C8EB33.jpeg
Next to trim the plywood all flush, maybe add one more layer on the bottom, build a decorative wraparound, and maybe a couple pockets through the whole plinth to add extra mass.
 
This is looking great! Could you share some images of how that tonearm mount is accomplished? Looks like you could swivel it if needed. Very sharp already without the finishing touches : )
 
Will do!
But it has to sit here for the whole week intil I can get back to the workshop, so in a bit of a fit of impatience I transferred my cart over and moved the whole thing over.
73759575164__14BC057F-04C1-4A39-8611-3A86F1F6524E.jpeg
Everything right now is purely by feel but it works!! There is definitely strong rumble, but you know, this project just might bear fruit. The highs on this first side are nice and punchy. The piano isn’t coming through quite as straight as it should but I’m not gonna worry about that till I know everything is in the right place.
 
Panamafred said:
This is looking great! Could you share some images of how that tonearm mount is accomplished? Looks like you could swivel it if needed. Very sharp already without the finishing touches : )
Click to expand...
Here ya go. Pretty basic as it stands. But definitely functional. Stretch goal here is to be able to mount Micro Seiki bronze equivalents, but I’m going to have to figure out how to equip myself to bore true for a 30mm stub.
IMG_2897.jpeg
Here’s what the cavity looks like for all the gubbins:
IMG_2896.jpeg
 
Been enjoying listening to this, despite the rumble. But boy does it need seeing to. As a point of reference here’s the dimensions of the idler.IMG_2910.jpeg
 
What did you use for the rubber part ? Considering a DIY idler on something just for something to do.
 
So, the idler was built by a guy who does idlers who is local to me. It's made from one of his series production ones. He doesn't specify exactly what the tire is made from on his website. Currently he offers Lenco, Garrard, Dual(!) Elac(!) and Thorens. He's not sure if he's gonna offer McCurdy wheels, but apparently he has RoKs in his test collection, so that may happen, as they are very similar. I'll update this with a direct link if he's willing to be public about it all.
Details as I know them: 6061 aluminum wheel, mystery high end polymer rubber tire, bronze oilite bushing, teflon thrust washer, and rubber o-ring to replace the circlip.
 
FreaK said:
So after a little back and forth with myself I decided to start a dedicated thread. I recently acquired one of these ‘tables as a motor unit after being pretty struck by the overall elegance of the approach.

They’re a funny case because they are like a slightly more agricultural cousin of ROKs more specifically the Rondine/B12 H, they seem to fetch a little bit more money despite that. The top plate for instance is sheet aluminium. The platter as well. The bearing design is similar but uses the drop out circlip thrust pad solution in a 2” diameter alu cylinder, rather than the closed end cast (iron?) Rek O Kut style.

This uses the 1/100hp Ashland D80KBU, whereas it seems the ROKs typically use the 1/200 variant, though ROK was apparently known for having loads of running changes as well. To that end I’ve seen at least three motor mounting schemes on these.

Currently planning on a plinth build not too dissimilar in format to the attached. The swivelling armboards in my case to be to the Micro Seiki equivalent fitment. I’m hoping to set myself up well for experimenting with different arm lengths and styles. I’ve started off by sourcing a Fidelity Research FR-24. Stretch goals include homebrew Schroeder or Supatrack. Love to try linear tracking but so many of the designs are ungainly.


Anyway, this will be the official spot for updates on this project as it moves along.
Hopefully I don’t blow up the value of these tables in the process, i think the going rate is about spot on for what they offer relative to what they demand, though sonics will be the final arbiter of that.
Click to expand...
Hello, does anyone know what a McCurdy CH-13 turntable means? I have one but I can not find one on the internet , only Ch-12 not sure what my turntable is, thank you for any help .
FreaK said:
So after a little back and forth with myself I decided to start a dedicated thread. I recently acquired one of these ‘tables as a motor unit after being pretty struck by the overall elegance of the approach.

They’re a funny case because they are like a slightly more agricultural cousin of ROKs more specifically the Rondine/B12 H, they seem to fetch a little bit more money despite that. The top plate for instance is sheet aluminium. The platter as well. The bearing design is similar but uses the drop out circlip thrust pad solution in a 2” diameter alu cylinder, rather than the closed end cast (iron?) Rek O Kut style.

This uses the 1/100hp Ashland D80KBU, whereas it seems the ROKs typically use the 1/200 variant, though ROK was apparently known for having loads of running changes as well. To that end I’ve seen at least three motor mounting schemes on these.

Currently planning on a plinth build not too dissimilar in format to the attached. The swivelling armboards in my case to be to the Micro Seiki equivalent fitment. I’m hoping to set myself up well for experimenting with different arm lengths and styles. I’ve started off by sourcing a Fidelity Research FR-24. Stretch goals include homebrew Schroeder or Supatrack. Love to try linear tracking but so many of the designs are ungainly.


Anyway, this will be the official spot for updates on this project as it moves along.
Hopefully I don’t blow up the value of these tables in the process, i think the going rate is about spot on for what they offer relative to what they demand, though sonics will be the final arbiter of that.
Click to expand...
 
Yes I am sorry it's a ch14 I thought it was ch13 lol my memory is bad here are pictures
 

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