Refinishing a B1 or a B2

Discussion in 'Yamaha' started by belgianbrain, Mar 7, 2017.

  1. belgianbrain

    belgianbrain AK Subscriber Subscriber

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    So I start hunting for my next project, which will likely keep me entertained for the remainder of the year.

    Thinking of finding a B-1 or a B-2 and going absolutely mental on it. (kind of like Mr. Yamaha is doing)

    If I can find a mint one, great, but most of these units that come up are quite challenged, cosmetically.

    Has anyone ever tried refinishing the case on one of these? Spray paint? Something more sophisticated?

    I've re-veneered a set of NS-1000s before (and I'm no carpenter) so I am not scared of learning and experimenting.
     
  2. rottalpha

    rottalpha Yamaholic Subscriber

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    there are a couple of b-2s and a b-1 on the auction site.
     
  3. belgianbrain

    belgianbrain AK Subscriber Subscriber

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    I am aware. Two of those three units are in the Russian Federation, appear a bit molested, and have very high prices stuck to them given their condition. I would not trust them.

    The third I considered, but after corresponding with the seller, he too seems a bit grumpy or shady!

    That site is always an interesting experience.
     
    Last edited: Mar 7, 2017
  4. Mr. Yamaha

    Mr. Yamaha With a hint of Kenwood Subscriber

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    Uncle Paul likes this.
  5. Oilmaster

    Oilmaster Ozzy Subscriber

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    Yes, and as you could/should spot..... changing the faceplate colour without changing the VU-meter background is a complete fiasco.
    So, if you engage in that adventure, you also ought to address the VU-meters, unless you go for a full black faceplate
     
  6. Mr. Yamaha

    Mr. Yamaha With a hint of Kenwood Subscriber

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    Yeah that's horrible, I think it should at least gets it's original color. It was more about the process / silk screening.
     
  7. zaibatsu

    zaibatsu Active Member

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    The B-1 has the tokin outputs rather than the originals. I wonder if that makes a difference to the sound or is OK? I'm sure @Oilmaster could comment.

    I think the silkscreening is the hard part, if you can find a reputable source for that process, the rest would just be a matter of removing everything from the part in question and repeating the factory process. Personally I would never paint a faceplate if it was originally anodized, anodizing is a much more durable coating, and can be repeated with success. It's not very expensive for a small part like that either.

    If the parts were originally painted (top covers and base plates), I've found that automotive heat-curing paint (for engines etc) works well and is quite durable. Usually I'd go for matte black sprayed on in one or two very light coats, followed by leaving it to dry, followed by careful curing with a heat-gun. The last step is the key, and after that it's usually best to leave it for a week or so to achieve a full cure.

    I'd always try and find examples with nice faceplates to begin with though, everything else can be fixed quite easily.
    Also don't you already have a B-2? I'd get the B-1 if there's a choice!
     
  8. Vint Age

    Vint Age B-1 With Yamaha

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    There are at least 3 different Tokin 2SK180 V-FET/SIT's types still available, probably not for long though, and possibly more. The C and D types are the closest to the 2SK77 as far as the Vgs parameter goes. I have no direct experience with those but I've read lots of good comments elsewhere about them. I do have direct experience with the non C/D type. They require modifications to the driver board circuitry because of their lower bias voltage but once done they work very well and after several hours of A/B listening neither myself or my wife could tell any difference between the 2SK77 B-1 and the 2SK180 one. Both sounded superb to our ears.:thumbsup: The Tokin B-1 did have slightly lower output than the K77 B-1 but not by that much. I can't recall the exact difference anymore.
     
  9. rottalpha

    rottalpha Yamaholic Subscriber

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    The B-2 faceplate is factory painted with a paint that is very smudge prone. A good powder-coat paint is probably the best cure. Automotive paint would work for the chassis, but it would not be my first choice.

    Edit: same smudge prone paint on the UC-1
     
  10. belgianbrain

    belgianbrain AK Subscriber Subscriber

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    The challenge would be the labeling. I could probably dispense with all the lettering, except for the main title that says "Yamaha Natural Sound Stereo Power Amplifier B-2", for example. I wonder if you could just scan the face plate and have little clear white lettering stickers made. Or maybe a professional metal finishing place could actually replace the labels with paint on the new surface. :idea:

    I did something similar when I refinished my NS-1000M. I scanned the label and sent it to a company that did machined metal lamacoids. They almost look better than the originals.
     
  11. rottalpha

    rottalpha Yamaholic Subscriber

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    s
    silk screening at a professional place is your answer....but why the headache? Buy one that is in decent shape and just "go crazy" with what's under the hood
     
  12. vintagejapan

    vintagejapan AK Member Subscriber

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    That would be me!

    The case was painted and silkscreen printed from a shop here in Japan.

    Didn't think was worth the hassle of doing the meters also.

    Guess it is just a matter of taste. I personally don't think it is a "complete fiasco"
     
  13. Mr. Yamaha

    Mr. Yamaha With a hint of Kenwood Subscriber

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  14. belgianbrain

    belgianbrain AK Subscriber Subscriber

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    Yes, I emailed that guy asking for better pictures of the case, because it looks quite rough in the pictures. He seemed to get irritated and just told me it was old and used, not new. No schiit. :rolleyes:

    I would actually prefer a B1 for my next project, since I already have a B2. I look at B2s because I sometimes think it would be nice to have some extra parts around just in case.
     
  15. vintagejapan

    vintagejapan AK Member Subscriber

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    Will do. I apologise never sold anything here before!
     
  16. luvvinvinyl

    luvvinvinyl Admin Staff Member Admin Subscriber

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    Mod note: posts offering items for sale, or referring to same, have been deleted.
     
  17. Mark B

    Mark B Yamaha Fan Subscriber

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    A damp sponge and a bit of Murphy's Oil Soap works nicely on the painted finish of the B-2, C-1 & UC-1.
     
    Mr. Yamaha and Uncle Paul like this.
  18. rottalpha

    rottalpha Yamaholic Subscriber

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    Thank you Mark!
     
  19. belgianbrain

    belgianbrain AK Subscriber Subscriber

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    Wow. Awesome suggestion, Mark! I never would have considered using Murphy's oil soap on a painted metal surface.

    My B2 looked tired and weathered, despite all the cleaning I'd tried in the past.

    I used a bit of Murphy's, and WOW - it looks almost new!
     
  20. Mark B

    Mark B Yamaha Fan Subscriber

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    :thumbsup:
     

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