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    New DIY Turntable

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    pigface

    Posts : 79
    Join date : 2011-04-10
    Location : pittsburgh

    New DIY Turntable

    Post by pigface on Sun Mar 12, 2017 5:24 pm

    With all the posts about new fangled  turntables showing up here lately  I have some
    pictures of my new  DIY turntable  . I just finished it  and have been giving it a good
    listening too for a couple weeks  now , and it sounds very nice , better than expected .
       I can already tell the bass is definatly tighter sounding and the vocals smoother and
    more natural  than the table its replacing , a VPI scout .
    Not that the VPI sounded bad , it didn’t.
            The plinth is basic , unsprung , just 3” thick MDF, 4 four pieces of laminated mdf
    and veneered . The 12” acrylic  platter and bearing is a vpi unit
    and the 12” tonearm is by SME .  And rests on adjustable aluminum O ringed feet .   I
    hadn’t planned on spending that much on a tonearm ! but it was on sale . And I’ve heard
    from two different dealers that SME is raising the prices 25% soon So ??  The armboard
    is from a Michell Orbe Gyrodec  (as is the top of the motor pod , modified to work )  and was just
    the right spacing  height for tone arm to platter height . The cartrige I’m using right now
    is a Dynavector  DV20X2 .
        The original motor pod I made was also made of mdf and veneer like the plinth  with a Hurst
    300 rpm motor and vpi hrx  pulley . I’m running a Phoenix  Falcon psu  motor speed
    controller and  Roadrunner tach since I wasn’t sure how the platter speed was going to be
    .  For some reason with the original wood cased motor pod the motor was noisy
    when it got warm , and it did get warm  after a couple hours  playing  .  So I made another
    housing out of 1/2” thick aluminum tubing . 100% better  almost dead quiet and runs much
    cooler also . I’ve never seen a motor pod made out of wood before , maybe that should have
    told me something , but it looked good .
          Since I didn’t know what size belt I needed until it was finished , I’ve been using 2
    wraps of knotted  6 lb mono fishing line instead and it has been working perfect so far . I
    tried a less stretchy silk thread people recomended , it worked good also but I had to tension it more than the
    fishing line to keep it from slipping and the platter speed seemed less stable , and because
    of more tension the motor was transfering some noise to the turntable . Although I
    couldn’t hear it from my listening position it was annoying .    
      But so far I’m very happy with how it turned out and sounds .

    The veneer is  Hawaiian  Koa wood if anyone is curious , and funnily it smells almost like
    a cigar  when sanding it .  





    Original  (noisy ) motor pod in this pic.


    New  motor pod here. Check out how close the speed is controlled . The right side box is the tach .The left is the speed PSU .




    Mock up .












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    peterh

    Posts : 882
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: New DIY Turntable

    Post by peterh on Sun Mar 12, 2017 6:20 pm

    I'm impressed, this is nice !

    You could make a space in the plinth for a riaa amplifier, some would like the tubes to
    extend above the surface, others don't care. But close to the tonearm is where the
    riaa amp should be located.


    ramon68

    Posts : 99
    Join date : 2009-04-12
    Age : 77
    Location : naples fl

    Re: New DIY Turntable

    Post by ramon68 on Sun Mar 12, 2017 7:58 pm

    Beautiful job.
    It's good to know one can diy a TT using Scout parts that is better than the Scout.

    pigface

    Posts : 79
    Join date : 2011-04-10
    Location : pittsburgh

    Re: New DIY Turntable

    Post by pigface on Sun Mar 12, 2017 8:51 pm

    I was thinking about mounting the motor in the plinth  but I didn't want to chance the posibility of vibration . And now I see that was the right desision with the motor noise problem I had .  And  I  am running this through my PH15 into my SP14 . so no other RIAA needed . And it would be a shame to cover the nice wood grain . There is a bit of empty space because on top because of the longer tone arm .

    I like my Scout , I just had a personal - mental issue with the tone arm design  . Ever since I got it I didn't like how the tone arm wand  just sat and pivoted on  a pointed  spike  with no  bearings for support . It feels just feels too flimsy to me .
    It was between the VPI 12" platter and bearing and the Michell orbe unit , but I found the vpi on the bay less than half the price . No choice there .
    avatar
    cci1492

    Posts : 109
    Join date : 2016-05-09
    Age : 57
    Location : Bergen County NJ

    Re: New DIY Turntable

    Post by cci1492 on Sun Mar 12, 2017 10:45 pm

    Very impressive! If it sounds half as cool as it looks it's a home run.

    Dogstar

    Posts : 292
    Join date : 2014-06-23

    Re: New DIY Turntable

    Post by Dogstar on Mon Mar 13, 2017 7:28 am

    Very impressive build. Your skills are immediately apparent from the photos.

    I have a few questions though. A few of the photos show the motor to be in a rectangular plinth about the same depth and height as the main plinth. And other photos show the motor to be in a cylindrical enclosure. Are there two different motors or two different motor enclosures for the same motor?

    Also can you tell me the Hurst part number for the motor?
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    Ernstmach

    Posts : 82
    Join date : 2015-08-30
    Location : The Great Mitten.

    Re: New DIY Turntable

    Post by Ernstmach on Mon Mar 13, 2017 9:15 am

    Well done! Really like the Koa.

    pigface

    Posts : 79
    Join date : 2011-04-10
    Location : pittsburgh

    Re: New DIY Turntable

    Post by pigface on Mon Mar 13, 2017 6:38 pm

    On the motor . I originally built the wooden rectangular motor housing when I built the plinth because I thought it would look good with the turntable ,  but  the motor was noisy in the wood housing  .  The hotter the motor got the noisier , the more strain on it it got noisier it got , and when  you would change speed to 45rpm it really howled . So I decided to build one from aluminum tubing and try that  and it is dead quiet so far . The tube is 4 12 od. x 1/2" thick with a 1" thick bottom disc of aluminum .  I used the thickness for weight so it doesn't move  or vibrate under tension .  I covered with a wrap of veneer to match the plinth .  
    So yes the same motor  in two different housings.
    The hurst # I bought  is  3201-001  Model PA DD Synchronous Motor .    300rpm   7.5 watts (http://www.hurst-motors.com/papbdirectdrive.html)  They make a motor with more torque  but it probly isn't needed .

    It works good and turns the heavy 12" x 2" platter and a heavy stainless record clamp no problem . I think that is the same as the 300 rpm upgrade motor vpi sells for the scout and others ?


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    Ernstmach

    Posts : 82
    Join date : 2015-08-30
    Location : The Great Mitten.

    Re: New DIY Turntable

    Post by Ernstmach on Mon Mar 13, 2017 8:04 pm

    I liked the first motor block. Looks good with the plinth but the round motor mount also looks good.
    Is the drive belt/cord wrapped around the motor pulley?
    How is the drive belt tension set?
    Sorry for the questions... Your example is an inspiration!

    pigface

    Posts : 79
    Join date : 2011-04-10
    Location : pittsburgh

    Re: New DIY Turntable

    Post by pigface on Tue Mar 14, 2017 7:36 pm

    I liked the first one also . But function over form in this case .  The belt is like you see it in the above photo it just wraps around the motor then around the platter .  And you just slide the motor unit away from the platter enough to tension the belt enough that the motor does not slip when turning the platter and the speed stays stable .

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