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    Painting transformers

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    mcgyver74

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    Join date : 2017-03-24
    Location : Jersey City, NJ

    Painting transformers

    Post by mcgyver74 on Tue Mar 28, 2017 3:02 pm

    Sorry for all the dumb questions but got another one Smile


    I am getting ready to start my build, and one of the things I would like to do is paint the transformer so they look nice.

    Bob's instructions actually include a sheet about that but it's a little confusing...
    He says to obtain 8x32 nuts and bolts and replace the transformers existing bolts one at a time working diagonally. Not sure why you do that...does this mean you cannot remove the end bells without damaging the transformers??


    Thanks in advance!

    mcgyver74

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    Re: Painting transformers

    Post by mcgyver74 on Tue Mar 28, 2017 3:31 pm

    Ok Bob just emailed me and said it's fine to pull the bells...Sorry again for the dumb question Smile
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    sKiZo

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    Location : Michigan USA

    Re: Painting transformers

    Post by sKiZo on Tue Mar 28, 2017 3:44 pm

    Any plans to scrape down the stacks? Mine had a lot of dried goop on the surface from the plate bonding material. Back stroked them with a single sided razor blade, then dragged a small gouge along the plate seams to indent them just a touch to give them an even look.  Bit of extra work, but I figured it was worth it ...



    I also went with Bob's recommendation to use the Krylon satin black. Bolting the iron to some scrap plywood helps for handling them. You'll also want the paint to bake on before assembly. Nothing like a few hours in the hot sun for that.



    PS ... if you'll notice, I also used the extra screws and painted the iron with the bells installed. This kept the original hardware unpainted and purty and gave me good clean seams around the bells. You'll notice I also taped off all the wiring with painters blue ...

    Oh. Worth mentioning ... you don't want to leave ANY of the iron exposed after scraping and cleaning as it'll rust right quick. I just left the bottom of the OT's alone ... ain't nobody ever gonna see those.

    mcgyver74

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    Re: Painting transformers

    Post by mcgyver74 on Tue Mar 28, 2017 3:52 pm

    Smile I am planning to paint the end bells a nice charcoal grey and sand/paint the rings black, hadn't thought about using a gouge on them to make them pop but I may do that Smile
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    Bob Latino
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    Re: Painting transformers

    Post by Bob Latino on Tue Mar 28, 2017 8:06 pm

    The best BLACK paint I have found to paint transformers with is the Krylon # 2421 "Fusion" Satin Black. This is a semi-gloss black paint that sets up hard with a nice low gloss finish. You can use a glossy paint but glossy paints can show more easily any imperfections in the paint. If you are careful and get no drips or runs and you like the glossy finish, then give it a shot. A "flat" black IMHO just does not look as nice as the satin (semi-gloss) finish. On the can of the Fusion paint, they mention that it is "for plastic" but it works just fine for metal like a tube amp's transformers. Another tip .. If you can't find the color you want in a semi-gloss finish, you can use the color you want and then "clear coat" over the color with Minwax Clear Satin Polyurethane. This will give a satin finish to any underlying color ... Don't worry about the transformer heat making the paint peel .. The power transformer will get up to about 140 degrees Fahrenheit max. As long as you prepared the surface properly (clean off any oil from the metal before you start painting), any paint will stand up to this temperature. Below is a link to a photo of a custom paint job on a VTA ST-120 done by our head VTA amp technician Bill Gratrix. It has black transformer laminations and copper colored transformer bells covered with a clear coat of satin polyurethane.

    Bob

    Custom VTA ST-120 paint job

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    sKiZo

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    Re: Painting transformers

    Post by sKiZo on Tue Mar 28, 2017 8:16 pm

    I try to use words like "pop" when describing stuff having to do with tubes ...

    Don't get too carried away ... all I was doing was evening out the grooves a bit prior to paint.

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    j beede

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    Location : California

    Re: Painting transformers

    Post by j beede on Tue Mar 28, 2017 9:05 pm

    High gloss enamel on the bells. Thin, thin, thin coat of flat black on the laminations after wire brushing.



    Last edited by j beede on Tue Mar 28, 2017 10:35 pm; edited 4 times in total

    Steve G

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    Join date : 2017-03-17
    Location : Carson City, NV

    Re: Painting transformers

    Post by Steve G on Tue Mar 28, 2017 9:36 pm

    I hope this photo shows up.  It didn't, I will try again.




    Last edited by Steve G on Tue Mar 28, 2017 9:50 pm; edited 2 times in total (Reason for editing : No photo.)
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    cci1492

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    Location : Bergen County NJ

    Re: Painting transformers

    Post by cci1492 on Wed Mar 29, 2017 8:23 am

    mcgyver, I think the idea is to remove the bells for paint, then put back the two screws with the nuts on each diagonal side so when you're handling the transformer while paining it, it has these two screws to provide a little extra support other than the shellac to hold it together. At least that's how I understood that part of the instructions. I didn't get it at first either, thought about it and came up with this explanation...I could be wrong!
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    cci1492

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    Re: Painting transformers

    Post by cci1492 on Wed Mar 29, 2017 8:25 am

    Steve G. WOW what a cool look!
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    Peter W.

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    Re: Painting transformers

    Post by Peter W. on Wed Mar 29, 2017 11:25 am

    I am going to throw something up in the air (pun intended as you read on) developed from years of restoring vintage radios and legacy audio equipment.

    a) there is nothing magical about painting - even hammertone paints these days are remarkably easy to use.
    b) Things do not have to be on the ground (on a solid surface) for painting.
    c) Several light coats are typically infinitely better than one heavy coat - unless protection is the sole and only purpose (High-zinc or rust-proofing paints, for example).

    So, if it is possible to hang the item to be coated up in the air - if one has the correct location for this - then coatings may be applied from all sides and all directions directly perpendicular to the surface to be coated, the ideal process.

    If there are machine-screw ends available, I will use a nut of the correct size on the end of that screw for suspension. If there are flange holes - I will use mono-filament fishing line, very thin for its strength and does not hold paint or stick.

    There are all sorts of nifty means to mask things. several coats of rubber cement will protect a surface, then may be rubbed off with a finger after the coating cures. Painter's blue tape. soft rubber gasket material may be jammed in the bell holes to prevent material from getting up inside the transformer - if the bells are to be left in place.

    But it is nice not to have any blind (uncoated) areas on anything - as the nature of corrosion, is such that it will inevitably start at such a transition as any galvanic action will be concentrated at such transitions (another reason not to add 'third wires' on devices not designed against them - do I need to explain why?).

    For the same reason, I would also suggest that if end-bells are to be coated, that the inside also be coated. Not that we expect that our amps will be subject to damp locations, salt air or the like - but it is nice to have one less worry.

    mcgyver74

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    Re: Painting transformers

    Post by mcgyver74 on Wed Mar 29, 2017 12:46 pm

    Thanks guys, I have decided to go a wee bit further and make some mods to my case.

    So here is what I am planning.

    1) Paint transformer end bells
    2) Paint the transformer "edges" (The laminated part??)
    3) Powder coat the chassis gunmetal grey.

    I am doing the powder coat on the chassis because when my wife saw this, she didn't like the look of the 2 tube sockets on the front that are only used for bias adjust (She's an Italian fashonista LOL:) ) as they were to quote her directly "Ugly as hell" Smile

    So I will be finding a place that can fill them in properly, and then I will mount on the top 2 points where I can easily put a DVOM probe to measure bias (One that will easily hold the probe so I don't have to hold the probe while adjusting) then powdercoat the rest of the chassis..should look sharp Smile
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    Peter W.

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    Re: Painting transformers

    Post by Peter W. on Wed Mar 29, 2017 1:03 pm

    mcgyver74 wrote:Thanks guys,   I have decided to go a wee bit further and make some mods to my case.

    So here is what I am planning.

    1) Paint transformer end bells
    2) Paint the transformer "edges" (The laminated part??)
    3) Powder coat the chassis gunmetal grey.

    I am doing the powder coat on the chassis because when my wife saw this, she didn't like the look of the 2 tube sockets on the front that are only used for bias adjust (She's an Italian fashonista LOL:) ) as they were to quote her directly "Ugly as hell"   Smile

    So I will be finding a place that can fill them in properly, and then I will mount on the top 2 points where I can easily put a DVOM probe to measure bias (One that will easily hold the probe so I don't have to hold the probe while adjusting) then powdercoat the rest of the chassis..should look sharp Smile

    https://www.google.com/search?q=heyco+knock+out+seals&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjwgMeBl_zSAhUiqlQKHRDtB0EQ_AUIBygC&biw=1242&bih=557  

    https://www.grainger.com/category/ecatalog/N-1z0dt8k  

    Plastic or chrome, before, or after painting, and no permanent alterations to the chassis. And they come in many sizes from 1/4" to well over 4".
    Once past the fact that you are probably *not* planning to use a cage (no cats, dogs, offspring involved), putting probe points on top of the chassis are no big deal.

    http://www.mouser.com/ProductDetail/Pomona/5935-0/?qs=u1iBJdNqp6g%252bjaQd8QdaQg%3D%3D&gclid=Cj0KEQjwtu3GBRDY6ZLY1erL44EBEiQAAKIcvsWUqpRXa1aPTlVYi2zBv7cpjOnsGYvb6TKHiK6HIhkaAo058P8HAQ  Come in colors, too.

    De gustibus et coloribus non est disputandum.

    My sole comment on "gun metal grey".

    mcgyver74

    Posts : 74
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    Location : Jersey City, NJ

    Re: Painting transformers

    Post by mcgyver74 on Wed Mar 29, 2017 2:14 pm

    She prefers a smooth front (Keep yer minds out of the gutter LOL!! Smile ) which is why I was thinking to have the sockets deleted...but that may be an option.

    Those kind of test jacks are exactly what I was thinking of,  I will be running a cage (we do have our neighbors 2 year old who is in our apartment often, and again wifey prefers the look Smile )

    Lifting the cage off once a month to check bias is not a huge deal IMHO,.....

    But I like the caps idea Smile


    Oh and
    Cum fit, coloribus, me utramque partem valet, tamen ut semper sapiens beatus in uxorem
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    Peter W.

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    Re: Painting transformers

    Post by Peter W. on Wed Mar 29, 2017 3:22 pm

    Writing of minds in gutters - there are these:

    http://www.pipeendcaps.com/pic/201361213491.gif They come in a number of sizes.

    quidquid Latine dictum sit altum videtur

    mcgyver74

    Posts : 74
    Join date : 2017-03-24
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    Re: Painting transformers

    Post by mcgyver74 on Wed Mar 29, 2017 4:48 pm

    Peter W. wrote:

    quidquid Latine dictum sit altum videtur  


    Nos ex latrinariam Smile
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    sKiZo

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    Location : Michigan USA

    Re: Painting transformers

    Post by sKiZo on Wed Mar 29, 2017 5:56 pm

    Any ground issues with a powder coated chassis? Question
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    Bob Latino
    Admin

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    Re: Painting transformers

    Post by Bob Latino on Wed Mar 29, 2017 6:16 pm

    sKiZo wrote:Any ground issues with a powder coated chassis?  Question

    All the ground connections are inside the chassis which I do not believe is powder coated ..

    Bob

    mcgyver74

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    Re: Painting transformers

    Post by mcgyver74 on Wed Mar 29, 2017 7:04 pm

    Well they can try to powder coat only one side, but that may not look as nice, but using the chassis as a ground plane is nothing I cannot solve with my trusty dremel and a wire brush Smile

    Only question is to the transformers need to "sit" on the bare metal as a ground plane?
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    Bob Latino
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    Re: Painting transformers

    Post by Bob Latino on Wed Mar 29, 2017 7:10 pm

    mcgyver74 wrote:

    Only question is to the transformers need to "sit" on the bare metal as a ground plane?

    No - The transformers do not have to sit directly on the metal of the chassis .. They can be insulated from the chassis and/or sit directly on the powder coating.

    Bob

    Steve G

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    Location : Carson City, NV

    Re: Painting transformers

    Post by Steve G on Wed Mar 29, 2017 7:21 pm

    I only powder coated the bottom of my chassis. Not necessarily because of grounding even though there are no connections to the base. I did it because I wanted to break-up the stainless look. And to match the transformers.

    mcgyver74

    Posts : 74
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    Location : Jersey City, NJ

    Re: Painting transformers

    Post by mcgyver74 on Wed Mar 29, 2017 8:47 pm

    Bob Latino wrote:
    No - The transformers do not have to sit directly on the metal of the chassis .. They can be insulated from the chassis and/or sit directly on the powder coating.

    Bob


    Awesome! Thanks Bob!!!

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